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Sample records for insecticide neem ec

  1. Efficacy of neem products and insecticides for the control of shoot fly Formosina flavipes Mall. of Cardamom (Elettaria Cardamomum Maton.).

    PubMed

    Naik, D Jemla; Belavadi, V V; Thippesha, D

    2006-01-01

    Experiments were conducted at Zonal Agricultural Research Station, Mudigere, India, for two years with an objective to study the population fluctuation, seasonal incidence and evaluation of neem products and insecticides for their efficacy against cardamom shoot fly. During the study period, it was noticed that shoot fly population the increased during the dry months (March, May and October) but was low from June to September months. The population exhibited a negative correlation with rainfall, minimum temperature and maximum relative humidity and positive correlations with maximum temperature and sunshine h. Among the six insecticides tested, phorate, phorate with neem cake and neem cake alone were found superior over other treatments. The present study clearly indicated that application of neem cake helps not only in reduction of shoot fly incidence but also enhances the production of side suckers compared to other treatments.

  2. Population-level effects of the neem insecticide, Neemix, on Daphnia pulex.

    PubMed

    Stark, J D

    2001-07-01

    Although natural insecticides from the neem tree are generally perceived as less harmful to the environment than synthetic insecticides, new evidence indicates that these products may pose a risk to certain nontarget organisms. In this paper, acute and chronic effects of commercial neem insecticides on the aquatic invertebrate, Daphnia pulex were examined. The acute toxicity of two commercial neem insecticides, Neemix, Azatin and the experimental insecticide, RH-9999 to D. pulex was investigated using traditional 48 hr concentration-mortality estimates. Neemix and Azatin were equitoxic with LC50's of 0.68 and 0.57 ppm; RH-9999 was significantly less toxic with an LC50 of 13 ppm. A 10 d population growth study was conducted for Neemix and a Neemix formulation blank (Neemix devoid of the active ingredients) to determine whether the active ingredients of Neemix and/or components of the formulation were responsible for toxicity. D. pulex populations went to extinction after exposure to a Neemix concentration of 0.45 ppm azadirachtin (equivalent to the acute LC7). Neemix No Observable Effect Concentration (NOEC) and Lowest Observable Effect Concentration (LOEC) values for population growth were 0.045 and 0.15 ppm azadirachtin, respectively. The mean number of offspring per surviving female (Ro) declined in a concentration-dependent manner after exposure to Neemix with no offspring being produced after exposure to 0.45 ppm. Neemix NOEC and LOEC values for reproduction were 0.045 and 0.15 ppm, respectively. The formulation blank caused no mortality in the individuals used to start the population growth study but reduced reproduction and population growth accounting for 47% of the toxicity caused by Neemix at a concentration of 0.15 ppm. Thus, the formulation contributes substantially to the toxicity of Neemix but neem components are also toxic to D. pulex. Because the NOEC for population growth and reproduction were higher than the estimated environmental concentration of

  3. Management of mango hopper, Idioscopus clypealis, using chemical insecticides and Neem oil.

    PubMed

    Adnan, S M; Uddin, M M; Alam, M J; Islam, M S; Kashem, M A; Rafii, M Y; Latif, M A

    2014-01-01

    An experiment was conducted in Field Laboratory, Department of Entomology at Bangladesh Agricultural University, Mymensingh, during 2013 to manage the mango hopper, Idioscopus clypealis L, using three chemical insecticides, Imidacloprid (0.3%), Endosulfan (0.5%), and Cypermethrin (0.4%), and natural Neem oil (3%) with three replications of each. All the treatments were significantly effective in managing mango hopper in comparison to the control. Imidacloprid showed the highest efficacy in percentage of reduction of hopper population (92.50 ± 9.02) at 72 hours after treatment in case of 2nd spray. It also showed the highest overall percentage of reduction (88.59 ± 8.64) of hopper population and less toxicity to natural enemies including green ant, spider, and lacewing of mango hopper. In case of biopesticide, azadirachtin based Neem oil was found effective against mango hopper as 48.35, 60.15, and 56.54% reduction after 24, 72, and 168 hours of spraying, respectively, which was comparable with Cypermethrin as there was no statistically significant difference after 168 hours of spray. Natural enemies were also higher after 1st and 2nd spray in case of Neem oil. PMID:25140344

  4. Management of mango hopper, Idioscopus clypealis, using chemical insecticides and Neem oil.

    PubMed

    Adnan, S M; Uddin, M M; Alam, M J; Islam, M S; Kashem, M A; Rafii, M Y; Latif, M A

    2014-01-01

    An experiment was conducted in Field Laboratory, Department of Entomology at Bangladesh Agricultural University, Mymensingh, during 2013 to manage the mango hopper, Idioscopus clypealis L, using three chemical insecticides, Imidacloprid (0.3%), Endosulfan (0.5%), and Cypermethrin (0.4%), and natural Neem oil (3%) with three replications of each. All the treatments were significantly effective in managing mango hopper in comparison to the control. Imidacloprid showed the highest efficacy in percentage of reduction of hopper population (92.50 ± 9.02) at 72 hours after treatment in case of 2nd spray. It also showed the highest overall percentage of reduction (88.59 ± 8.64) of hopper population and less toxicity to natural enemies including green ant, spider, and lacewing of mango hopper. In case of biopesticide, azadirachtin based Neem oil was found effective against mango hopper as 48.35, 60.15, and 56.54% reduction after 24, 72, and 168 hours of spraying, respectively, which was comparable with Cypermethrin as there was no statistically significant difference after 168 hours of spray. Natural enemies were also higher after 1st and 2nd spray in case of Neem oil.

  5. Management of Mango Hopper, Idioscopus clypealis, Using Chemical Insecticides and Neem Oil

    PubMed Central

    Adnan, S. M.; Uddin, M. M.; Alam, M. J.; Islam, M. S.; Kashem, M. A.; Rafii, M. Y.; Latif, M. A.

    2014-01-01

    An experiment was conducted in Field Laboratory, Department of Entomology at Bangladesh Agricultural University, Mymensingh, during 2013 to manage the mango hopper, Idioscopus clypealis L, using three chemical insecticides, Imidacloprid (0.3%), Endosulfan (0.5%), and Cypermethrin (0.4%), and natural Neem oil (3%) with three replications of each. All the treatments were significantly effective in managing mango hopper in comparison to the control. Imidacloprid showed the highest efficacy in percentage of reduction of hopper population (92.50 ± 9.02) at 72 hours after treatment in case of 2nd spray. It also showed the highest overall percentage of reduction (88.59 ± 8.64) of hopper population and less toxicity to natural enemies including green ant, spider, and lacewing of mango hopper. In case of biopesticide, azadirachtin based Neem oil was found effective against mango hopper as 48.35, 60.15, and 56.54% reduction after 24, 72, and 168 hours of spraying, respectively, which was comparable with Cypermethrin as there was no statistically significant difference after 168 hours of spray. Natural enemies were also higher after 1st and 2nd spray in case of Neem oil. PMID:25140344

  6. The toxicity of a neem insecticide to populations of culicidae and other aquatic invertebrates as assessed in in situ microcosms.

    PubMed

    Scott, I M; Kaushik, N K

    2000-10-01

    Microcosm trials were conducted with the botanical insecticide Margosan-O(R) to assess the potential hazards of the product to aquatic organisms. Laboratory chronic bioassays with water from the treated microcosms were conducted to provide an estimate of the residual effect of Margosan-O. Results from chronic tests showed Margosan-O toxicity to be greater in the laboratory exposures than in situ with Culicidae larvae exposed to the same concentrations. Residue analyses of the active ingredient, azadirachtin, determined that it had a half-life of 36 to 48 h in water exposed to natural sunlight. Two applications of Margosan-O at the recommended application rate for pests did not harm aquatic invertebrates that are categorized as planktonic and filter feeding (Culex sp. and Daphnia sp.). However, the benthic invertebrate (Chironomus riparius) was affected by multiple applications of neem. These results show that the use of Margosan-O and possibly other neem extracts in or near aquatic environments could lead to disturbances in benthic populations and may cause decreases in numbers of organisms that are important in food web and nutrient cycling processes. PMID:10948283

  7. Effect of Neem (Azadirachta indica) on the Survival of Escherichia coli O157:H7 in Dairy Manure.

    PubMed

    Ravva, Subbarao V; Korn, Anna

    2015-07-01

    Escherichia coli O157:H7 (EcO157) shed in cattle manure can survive for extended periods of time and intervention strategies to control this pathogen at the source are critical as produce crops are often grown in proximity to animal raising operations. This study evaluated whether neem (Azadirachta indica), known for its antimicrobial and insecticidal properties, can be used to amend manure to control EcO157. The influence of neem materials (leaf, bark, and oil) on the survival of an apple juice outbreak strain of EcO157 in dairy manure was monitored. Neem leaf and bark supplements eliminated the pathogen in less than 10 d with a D-value (days for 90% elimination) of 1.3 d. In contrast, nearly 4 log CFU EcO157/g remained after 10 d in neem-free manure control. The ethyl acetate extractable fraction of neem leaves was inhibitory to the growth of EcO157 in LB broth. Azadirachtin, a neem product with insect antifeedant properties, failed to inhibit EcO157. Application of inexpensive neem supplements to control pathogens in manure and possibly in produce fields may be an option for controlling the transfer of foodborne pathogens from farm to fork. PMID:26184255

  8. Effect of Neem (Azadirachta indica) on the Survival of Escherichia coli O157:H7 in Dairy Manure.

    PubMed

    Ravva, Subbarao V; Korn, Anna

    2015-07-10

    Escherichia coli O157:H7 (EcO157) shed in cattle manure can survive for extended periods of time and intervention strategies to control this pathogen at the source are critical as produce crops are often grown in proximity to animal raising operations. This study evaluated whether neem (Azadirachta indica), known for its antimicrobial and insecticidal properties, can be used to amend manure to control EcO157. The influence of neem materials (leaf, bark, and oil) on the survival of an apple juice outbreak strain of EcO157 in dairy manure was monitored. Neem leaf and bark supplements eliminated the pathogen in less than 10 d with a D-value (days for 90% elimination) of 1.3 d. In contrast, nearly 4 log CFU EcO157/g remained after 10 d in neem-free manure control. The ethyl acetate extractable fraction of neem leaves was inhibitory to the growth of EcO157 in LB broth. Azadirachtin, a neem product with insect antifeedant properties, failed to inhibit EcO157. Application of inexpensive neem supplements to control pathogens in manure and possibly in produce fields may be an option for controlling the transfer of foodborne pathogens from farm to fork.

  9. Effect of Neem (Azadirachta indica) on the Survival of Escherichia coli O157:H7 in Dairy Manure

    PubMed Central

    Ravva, Subbarao V.; Korn, Anna

    2015-01-01

    Escherichia coli O157:H7 (EcO157) shed in cattle manure can survive for extended periods of time and intervention strategies to control this pathogen at the source are critical as produce crops are often grown in proximity to animal raising operations. This study evaluated whether neem (Azadirachta indica), known for its antimicrobial and insecticidal properties, can be used to amend manure to control EcO157. The influence of neem materials (leaf, bark, and oil) on the survival of an apple juice outbreak strain of EcO157 in dairy manure was monitored. Neem leaf and bark supplements eliminated the pathogen in less than 10 d with a D-value (days for 90% elimination) of 1.3 d. In contrast, nearly 4 log CFU EcO157/g remained after 10 d in neem-free manure control. The ethyl acetate extractable fraction of neem leaves was inhibitory to the growth of EcO157 in LB broth. Azadirachtin, a neem product with insect antifeedant properties, failed to inhibit EcO157. Application of inexpensive neem supplements to control pathogens in manure and possibly in produce fields may be an option for controlling the transfer of foodborne pathogens from farm to fork. PMID:26184255

  10. Environmental safety to decomposer invertebrates of azadirachtin (neem) as a systemic insecticide in trees to control emerald ash borer.

    PubMed

    Kreutzweiser, David; Thompson, Dean; Grimalt, Susana; Chartrand, Derek; Good, Kevin; Scarr, Taylor

    2011-09-01

    The non-target effects of an azadirachtin-based systemic insecticide used for control of wood-boring insect pests in trees were assessed on litter-dwelling earthworms, leaf-shredding aquatic insects, and microbial communities in terrestrial and aquatic microcosms. The insecticide was injected into the trunks of ash trees at a rate of 0.2 gazadirachtin cm(-1) tree diameter in early summer. At the time of senescence, foliar concentrations in most (65%) leaves where at or below detection (<0.01 mg kg(-1) total azadirachtin) and the average concentration among leaves overall at senescence was 0.19 mg kg(-1). Leaves from the azadirachtin-treated trees at senescence were added to microcosms and responses by test organisms were compared to those in microcosms containing leaves from non-treated ash trees (controls). No significant reductions were detected among earthworm survival, leaf consumption rates, growth rates, or cocoon production, aquatic insect survival and leaf consumption rates, and among terrestrial and aquatic microbial decomposition of leaf material in comparison to controls. In a further set of microcosm tests containing leaves from intentional high-dose trees, the only significant, adverse effect detected was a reduction in microbial decomposition of leaf material, and only at the highest test concentration (∼6 mg kg(-1)). Results indicated no significant adverse effects on litter-dwelling earthworms or leaf-shredding aquatic insects at concentrations up to at least 30 × the expected field concentrations at operational rates, and at 6 × expected field concentrations for adverse effects on microbial decomposition. We conclude that when azadirachtin is used as a systemic insecticide in trees for control of insect pests such as the invasive wood-boring beetle, emerald ash borer, resultant foliar concentrations in senescent leaf material are likely to pose little risk of harm to decomposer invertebrates. PMID:21531021

  11. Environmental safety to decomposer invertebrates of azadirachtin (neem) as a systemic insecticide in trees to control emerald ash borer.

    PubMed

    Kreutzweiser, David; Thompson, Dean; Grimalt, Susana; Chartrand, Derek; Good, Kevin; Scarr, Taylor

    2011-09-01

    The non-target effects of an azadirachtin-based systemic insecticide used for control of wood-boring insect pests in trees were assessed on litter-dwelling earthworms, leaf-shredding aquatic insects, and microbial communities in terrestrial and aquatic microcosms. The insecticide was injected into the trunks of ash trees at a rate of 0.2 gazadirachtin cm(-1) tree diameter in early summer. At the time of senescence, foliar concentrations in most (65%) leaves where at or below detection (<0.01 mg kg(-1) total azadirachtin) and the average concentration among leaves overall at senescence was 0.19 mg kg(-1). Leaves from the azadirachtin-treated trees at senescence were added to microcosms and responses by test organisms were compared to those in microcosms containing leaves from non-treated ash trees (controls). No significant reductions were detected among earthworm survival, leaf consumption rates, growth rates, or cocoon production, aquatic insect survival and leaf consumption rates, and among terrestrial and aquatic microbial decomposition of leaf material in comparison to controls. In a further set of microcosm tests containing leaves from intentional high-dose trees, the only significant, adverse effect detected was a reduction in microbial decomposition of leaf material, and only at the highest test concentration (∼6 mg kg(-1)). Results indicated no significant adverse effects on litter-dwelling earthworms or leaf-shredding aquatic insects at concentrations up to at least 30 × the expected field concentrations at operational rates, and at 6 × expected field concentrations for adverse effects on microbial decomposition. We conclude that when azadirachtin is used as a systemic insecticide in trees for control of insect pests such as the invasive wood-boring beetle, emerald ash borer, resultant foliar concentrations in senescent leaf material are likely to pose little risk of harm to decomposer invertebrates.

  12. Insecticidal activity of the granulosis virus in combination with neem products and talc powder against the potato tuberworm Phthorimaea operculella (Zeller) (Lepidoptera: Gelechiidae).

    PubMed

    Mascarin, G M; Delalibera, I

    2012-06-01

    The potato tuberworm Phthorimaea operculella (Zeller) is an important agricultural pest that causes significant economic losses to potato growers worldwide. The addition of an effective method of biological control for the potato tuberworm is greatly needed, and is currently unavailable in Brazil. The granulosis virus (Baculoviridae) is a promising biological control agent to protect post-harvest potatoes and in storage from the potato tuberworm. However, the control measure must be economically feasible. Liquid suspensions of a granulosis virus applied alone or in mixture with two commercial neem oil-based products (DalNeem™ and NeemAzal™), and a dry powder formulation of viral granules were evaluated for control of potato tuberworm larvae by treating potato tubers under laboratory conditions. High larval mortality (86.7%) was achieved when DalNeem and virus were applied together at 4 mg of azadirachtin/L and 10(4) occlusion bodies (OBs)/mL, respectively. This combination resulted in ≥50% efficacy in relation to their counterparts alone. Conversely, NeemAzal did not enhance virus effectiveness against larvae of the potato tuberworm. The talc-based virus formulation was used for dusting seed tubers at different concentrations and resulted in 100% larval mortality at 5 × 10(8) OBs/g. Formulated and unformulated virus provided 50% mortality at 166 OBs/g and at 5.0 × 10(5) OBs/mL, respectively. As a result, talc-based virus formulation had a better control efficiency on potato tuberworm than the aqueous virus suspension. The granulosis virus combined with DalNeem at low rates or formulated with talc powder is a viable option to control the potato tuberworm under storage conditions. PMID:23950047

  13. Sensitivity of brain cholinesterase activity to diazinon (BASUDIN 50EC) and fenobucarb (BASSA 50EC) insecticides in the air-breathing fish Channa striata (Bloch, 1793).

    PubMed

    Van Cong, Nguyen; Phuong, Nguyen Thanh; Bayley, Mark

    2006-05-01

    With the expansion of agricultural areas within the Mekong River Delta in Vietnam, a concurrent, dramatic increase has occurred in agrochemical usage. To date, little consideration has been given to the negative impacts of this agricultural activity on the aquatic resources of the region. Both acute toxicity and subacute effects on brain cholinesterase (ChE) of two of the most commonly used insecticides, diazinon and fenobucarb, on adult native snakehead (Channa striata) were evaluated in a static, nonrenewable system, the environmental parameters of which, such as dissolved oxygen, water temperature, and pH, fluctuated similarly to field conditions. Four levels of insecticides, from 0.008 to 0.52 mg/L (for diazinon) and from 0.11 to 9.35 mg/L (for fenobucarb), were tested to assess the effects on the brain ChE activity of the snakehead up to 30 and 10 d for diazinon and fenobucarb, respectively. Diazinon was highly toxic to this fish species, with a 96-h median lethal concentration (LC50) of only 0.79 mg/L, and it also caused long-term ChE inhibition, with activity still significantly inhibited by 30% after 30 d for the three highest concentrations. Fenobucarb was less toxic to this species, with a 96-h LC50 of 11.4 mg/L. Fenobucarb caused more rapid ChE inhibition but also rapid recovery. The results of the present study indicate an urgent need to regulate the usage of these pesticides in the Mekong River Delta. PMID:16704077

  14. Safety evaluation of neem (Azadirachta indica) derived pesticides.

    PubMed

    Boeke, Sara J; Boersma, Marelle G; Alink, Gerrit M; van Loon, Joop J A; van Huis, Arnold; Dicke, Marcel; Rietjens, Ivonne M C M

    2004-09-01

    The neem tree, Azadirachta indica, provides many useful compounds that are used as pesticides and could be applied to protect stored seeds against insects. However in addition to possible beneficial health effects, such as blood sugar lowering properties, anti-parasitic, anti-inflammatory, anti-ulcer and hepatoprotective effects, also toxic effects are described. In this study we present a review of the toxicological data from human and animal studies with oral administration of different neem-based preparations. The non-aqueous extracts appear to be the most toxic neem-based products, with an estimated safe dose (ESD) of 0.002 and 12.5 microg/kg bw/day. Less toxic are the unprocessed materials seed oil and the aqueous extracts (ESD 0.26 and 0.3 mg/kg bw/day, 2 microl/kg bw/day respectively). Most of the pure compounds show a relatively low toxicity (ESD azadirachtin 15 mg/kg bw/day). For all preparations, reversible effect on reproduction of both male and female mammals seem to be the most important toxic effects upon sub-acute or chronic exposure. From the available data, safety assessments for the various neem-derived preparations were made and the outcomes are compared to the ingestion of residues on food treated with neem preparations as insecticides. This leads to the conclusion that, if applied with care, use of neem derived pesticides as an insecticide should not be discouraged. PMID:15261960

  15. Neem cake: chemical composition and larvicidal activity on Asian tiger mosquito.

    PubMed

    Nicoletti, Marcello; Mariani, Susanna; Maccioni, Oliviero; Coccioletti, Tiziana; Murugan, Kardaray

    2012-07-01

    New pesticides based on natural products are urgently needed, in consideration of their environmental care and lower collateral effects. Neem oil, the main product obtained from Azadiractha indica A. Juss, commonly known as neem tree, is mainly used in medical devices, cosmetics and soaps, as well as important insecticide. Manufacturing of neem oil first includes the collection of the neem seeds as raw material used for the extraction. Neem cake is the waste by-product remaining after extraction processes. The quality of the oil, as that of the cake, strictly depends from the quality of seeds as well as from the type of extraction processes used, which strongly influences the chemical composition of the product. Currently, the different types of commercial neem cake on the market are roughly identified as oiled and deoiled cake, but several other differences can be detected. The differences are relevant and must be determined, to obtain the necessary correlation between chemical constitution and larvicidal activities. Six different batches of neem cake, marketed by several Indian and European companies, were analyzed by HPLC and HPTLC, and their fingerprints compared, obtaining information about the different compositions, focusing in particular on nortriterpenes, considered as the main active components of neem oil. Therefore, the chemical composition of each cake was connected with the biological activitiy, i.e., the effects of the extracts of the six neem cakes were tested on eggs and larvae of Aedes albopictus (Stegomyia albopicta) (Diptera: Culicidae), commonly known as Asian tiger mosquito. The results confirmed the previously reported larvicide effects of neem cake that, however, can now be related to the chemical composition, in particular with nortriterpenes, allowing in that way to discriminate between the quality of the various marketed products, as potential domestic insecticides.

  16. Neem cake: chemical composition and larvicidal activity on Asian tiger mosquito.

    PubMed

    Nicoletti, Marcello; Mariani, Susanna; Maccioni, Oliviero; Coccioletti, Tiziana; Murugan, Kardaray

    2012-07-01

    New pesticides based on natural products are urgently needed, in consideration of their environmental care and lower collateral effects. Neem oil, the main product obtained from Azadiractha indica A. Juss, commonly known as neem tree, is mainly used in medical devices, cosmetics and soaps, as well as important insecticide. Manufacturing of neem oil first includes the collection of the neem seeds as raw material used for the extraction. Neem cake is the waste by-product remaining after extraction processes. The quality of the oil, as that of the cake, strictly depends from the quality of seeds as well as from the type of extraction processes used, which strongly influences the chemical composition of the product. Currently, the different types of commercial neem cake on the market are roughly identified as oiled and deoiled cake, but several other differences can be detected. The differences are relevant and must be determined, to obtain the necessary correlation between chemical constitution and larvicidal activities. Six different batches of neem cake, marketed by several Indian and European companies, were analyzed by HPLC and HPTLC, and their fingerprints compared, obtaining information about the different compositions, focusing in particular on nortriterpenes, considered as the main active components of neem oil. Therefore, the chemical composition of each cake was connected with the biological activitiy, i.e., the effects of the extracts of the six neem cakes were tested on eggs and larvae of Aedes albopictus (Stegomyia albopicta) (Diptera: Culicidae), commonly known as Asian tiger mosquito. The results confirmed the previously reported larvicide effects of neem cake that, however, can now be related to the chemical composition, in particular with nortriterpenes, allowing in that way to discriminate between the quality of the various marketed products, as potential domestic insecticides. PMID:22422292

  17. Activity and biological effects of neem products against arthropods of medical and veterinary importance.

    PubMed

    Mulla, M S; Su, T

    1999-06-01

    Botanical insecticides are relatively safe and degradable, and are readily available sources of biopesticides. The most prominent phytochemical pesticides in recent years are those derived from neem trees, which have been studied extensively in the fields of entomology and phytochemistry, and have uses for medicinal and cosmetic purposes. The neem products have been obtained from several species of neem trees in the family Meliaceae. Six species in this family have been the subject of botanical pesticide research. They are Azadirachta indica A. Juss, Azadirachta excelsa Jack, Azadirachta siamens Valeton, Melia azedarach L., Melia toosendan Sieb. and Zucc., and Melia volkensii Gürke. The Meliaceae, especially A. indica (Indian neem tree), contains at least 35 biologically active principles. Azadirachtin is the predominant insecticidal active ingredient in the seed, leaves, and other parts of the neem tree. Azadirachtin and other compounds in neem products exhibit various modes of action against insects such as antifeedancy, growth regulation, fecundity suppression and sterilization, oviposition repellency or attractancy, changes in biological fitness, and blocking development of vector-borne pathogens. Some of these bioactivity parameters of neem products have been investigated at least in some species of insects of medical and veterinary importance, such as mosquitoes, flies, triatomines, cockroaches, fleas, lice, and others. Here we review, synthesize, and analyze published information on the activity, modes of action, and other biological effects of neem products against arthropods of medical and veterinary importance. The amount of information on the activity, use, and application of neem products for the control of disease vectors and human and animal pests is limited. Additional research is needed to determine the potential usefulness of neem products in vector control programs. PMID:10412110

  18. Toxic effects of the neem oil (Azadirachta indica) formulation on the stink bug predator, Podisus nigrispinus (Heteroptera: Pentatomidae)

    PubMed Central

    Zanuncio, José Cola; Mourão, Sheila Abreu; Martínez, Luis Carlos; Wilcken, Carlos Frederico; Ramalho, Francisco S.; Plata-Rueda, Angelica; Soares, Marcus Alvarenga; Serrão, José Eduardo

    2016-01-01

    This research investigated the effects of neem oil on mortality, survival and malformations of the non-target stink bug predator, Podisus nigrispinus. Neurotoxic and growth inhibitor insecticides were used to compare the lethal and sublethal effects from neem oil on this predator. Six concentrations of neem oil were topically applied onto nymphs and adults of this predator. The mortality rates of third, fourth, and fifth instar nymphs increased with increasing neem oil concentrations, suggesting low toxicity to P. nigrispinus nymphs. Mortality of adults was low, but with sublethal effects of neem products on this predator. The developmental rate of P. nigrispinus decreased with increasing neem oil concentrations. Longevity of fourth instar nymphs varied from 3.74 to 3.05 d, fifth instar from 5.94 to 4.07 d and adult from 16.5 and 15.7 d with 0.5 and 50% neem doses. Podisus nigrispinus presented malformations and increase with neem oil concentrations. The main malformations occur in wings, scutellum and legs of this predator. The neem oil at high and sub lethal doses cause mortality, inhibits growth and survival and results in anomalies on wings and legs of the non-traget predator P. nigrispinus indicating that its use associated with biological control should be carefully evaluated. PMID:27596436

  19. Toxic effects of the neem oil (Azadirachta indica) formulation on the stink bug predator, Podisus nigrispinus (Heteroptera: Pentatomidae).

    PubMed

    Zanuncio, José Cola; Mourão, Sheila Abreu; Martínez, Luis Carlos; Wilcken, Carlos Frederico; Ramalho, Francisco S; Plata-Rueda, Angelica; Soares, Marcus Alvarenga; Serrão, José Eduardo

    2016-09-06

    This research investigated the effects of neem oil on mortality, survival and malformations of the non-target stink bug predator, Podisus nigrispinus. Neurotoxic and growth inhibitor insecticides were used to compare the lethal and sublethal effects from neem oil on this predator. Six concentrations of neem oil were topically applied onto nymphs and adults of this predator. The mortality rates of third, fourth, and fifth instar nymphs increased with increasing neem oil concentrations, suggesting low toxicity to P. nigrispinus nymphs. Mortality of adults was low, but with sublethal effects of neem products on this predator. The developmental rate of P. nigrispinus decreased with increasing neem oil concentrations. Longevity of fourth instar nymphs varied from 3.74 to 3.05 d, fifth instar from 5.94 to 4.07 d and adult from 16.5 and 15.7 d with 0.5 and 50% neem doses. Podisus nigrispinus presented malformations and increase with neem oil concentrations. The main malformations occur in wings, scutellum and legs of this predator. The neem oil at high and sub lethal doses cause mortality, inhibits growth and survival and results in anomalies on wings and legs of the non-traget predator P. nigrispinus indicating that its use associated with biological control should be carefully evaluated.

  20. Toxic effects of the neem oil (Azadirachta indica) formulation on the stink bug predator, Podisus nigrispinus (Heteroptera: Pentatomidae).

    PubMed

    Zanuncio, José Cola; Mourão, Sheila Abreu; Martínez, Luis Carlos; Wilcken, Carlos Frederico; Ramalho, Francisco S; Plata-Rueda, Angelica; Soares, Marcus Alvarenga; Serrão, José Eduardo

    2016-01-01

    This research investigated the effects of neem oil on mortality, survival and malformations of the non-target stink bug predator, Podisus nigrispinus. Neurotoxic and growth inhibitor insecticides were used to compare the lethal and sublethal effects from neem oil on this predator. Six concentrations of neem oil were topically applied onto nymphs and adults of this predator. The mortality rates of third, fourth, and fifth instar nymphs increased with increasing neem oil concentrations, suggesting low toxicity to P. nigrispinus nymphs. Mortality of adults was low, but with sublethal effects of neem products on this predator. The developmental rate of P. nigrispinus decreased with increasing neem oil concentrations. Longevity of fourth instar nymphs varied from 3.74 to 3.05 d, fifth instar from 5.94 to 4.07 d and adult from 16.5 and 15.7 d with 0.5 and 50% neem doses. Podisus nigrispinus presented malformations and increase with neem oil concentrations. The main malformations occur in wings, scutellum and legs of this predator. The neem oil at high and sub lethal doses cause mortality, inhibits growth and survival and results in anomalies on wings and legs of the non-traget predator P. nigrispinus indicating that its use associated with biological control should be carefully evaluated. PMID:27596436

  1. Toxic effects of the neem oil (Azadirachta indica) formulation on the stink bug predator, Podisus nigrispinus (Heteroptera: Pentatomidae)

    NASA Astrophysics Data System (ADS)

    Zanuncio, José Cola; Mourão, Sheila Abreu; Martínez, Luis Carlos; Wilcken, Carlos Frederico; Ramalho, Francisco S.; Plata-Rueda, Angelica; Soares, Marcus Alvarenga; Serrão, José Eduardo

    2016-09-01

    This research investigated the effects of neem oil on mortality, survival and malformations of the non-target stink bug predator, Podisus nigrispinus. Neurotoxic and growth inhibitor insecticides were used to compare the lethal and sublethal effects from neem oil on this predator. Six concentrations of neem oil were topically applied onto nymphs and adults of this predator. The mortality rates of third, fourth, and fifth instar nymphs increased with increasing neem oil concentrations, suggesting low toxicity to P. nigrispinus nymphs. Mortality of adults was low, but with sublethal effects of neem products on this predator. The developmental rate of P. nigrispinus decreased with increasing neem oil concentrations. Longevity of fourth instar nymphs varied from 3.74 to 3.05 d, fifth instar from 5.94 to 4.07 d and adult from 16.5 and 15.7 d with 0.5 and 50% neem doses. Podisus nigrispinus presented malformations and increase with neem oil concentrations. The main malformations occur in wings, scutellum and legs of this predator. The neem oil at high and sub lethal doses cause mortality, inhibits growth and survival and results in anomalies on wings and legs of the non-traget predator P. nigrispinus indicating that its use associated with biological control should be carefully evaluated.

  2. Neem derivatives are not effective as toxic bait for tephritid fruit flies.

    PubMed

    Silva, M A; Bezerra-Silva, G C D; Vendramim, J D; Mastrangelo, T; Forim, M R

    2013-08-01

    Neem derivatives have been widely touted as replacements for pesticides. A feasible replacement of synthetic insecticides in the management of fruit flies could be to use neem products in baits. This study evaluated the bioactivity of neem (Azadirachta indica A. Juss) derivatives in bait for adults of Anastrepha fraterculus (Wiedemann) and Ceratitis capitata (Wiedemann). The estimated LCs50 values for A. fraterculus and C. capitata were 7,522 ppm (18.40 ppm of azadirachtin) and 1,368 ppm (3.35 ppm of azadirachtin), respectively, using an aqueous extract of neem seeds in bait after 10 d of experimentation. No significant differences in the mortality of A. fraterculus and C. capitata adults exposed to baits made from different extracts and neem oil were observed after 3 h or 2 or 6 d; differences among the treatments were observed only on the 10th day of the evaluation. We conclude that neem derivatives applied as a bait spray over citrus plants did not demonstrate a toxic effect on A. fraterculus and C. capitata. The reasons for the low efficacy of the neem bait on Tephritid fruit flies are discussed. PMID:24020292

  3. Neem derivatives are not effective as toxic bait for tephritid fruit flies.

    PubMed

    Silva, M A; Bezerra-Silva, G C D; Vendramim, J D; Mastrangelo, T; Forim, M R

    2013-08-01

    Neem derivatives have been widely touted as replacements for pesticides. A feasible replacement of synthetic insecticides in the management of fruit flies could be to use neem products in baits. This study evaluated the bioactivity of neem (Azadirachta indica A. Juss) derivatives in bait for adults of Anastrepha fraterculus (Wiedemann) and Ceratitis capitata (Wiedemann). The estimated LCs50 values for A. fraterculus and C. capitata were 7,522 ppm (18.40 ppm of azadirachtin) and 1,368 ppm (3.35 ppm of azadirachtin), respectively, using an aqueous extract of neem seeds in bait after 10 d of experimentation. No significant differences in the mortality of A. fraterculus and C. capitata adults exposed to baits made from different extracts and neem oil were observed after 3 h or 2 or 6 d; differences among the treatments were observed only on the 10th day of the evaluation. We conclude that neem derivatives applied as a bait spray over citrus plants did not demonstrate a toxic effect on A. fraterculus and C. capitata. The reasons for the low efficacy of the neem bait on Tephritid fruit flies are discussed.

  4. Effectiveness of different emulsifiers for neem oil against the western flower thrips (Thysanoptera, Thripidae) and the warehouse moth (Lepidoptera, Pyralidae).

    PubMed

    Schroer, S; Sermann, H; Reichmuth, C; Büttner, C

    2001-01-01

    The neem tree produces highly specified acting insecticides mainly in its seeds. By pressurizing or extracting the seeds an insecticide oil can be manufactured. For successful application emulsifiers are needed to render the oil soluble in water. The heavy oil has to be stable in emulsion, but on the other hand the surfactant should not reduce the ecological property of the neem oil. The emulsifiers Lutensol TO10, Emulan ELP, Rimulgan and Tween 80 and for comparison the formulation NeemAzal-T/S were tested in their emulsion stability, as well as in their insecticidal effects towards two different insect pests: The western flower thrips Frankliniella occidentalis and the ware house moth Ephestia elutella. The emulsifiers were applied purely, and in different contents mixed in neem oil. Data showed significant differences of mortality and development on the tested pests. Lutensol TO10 and Emulan ELP caused spontaneous mortality on the western flower thrips and an additive efficacy when mixed with neem oil. Rimulgan led to mortality of the larvae of the warehouse moth. NeemAzal showed in both bioassays the highest efficacy of 95% mortality. PMID:12425067

  5. Aqueous Neem Extract Versus Neem Powder on Culex quinquefasciatus: Implications for Control in Anthropogenic Habitats

    PubMed Central

    Kudom, Andreas A.; Mensah, Ben A.; Botchey, Mary A.

    2011-01-01

    Control programs using conventional insecticides to target anthropogenic mosquito habitats are very expensive because these habitats are widespread, particularly in cities of most African countries. Additionally, there are serious environmental concerns regarding large-scale application of most conventional insecticides. Clearly there is a need for alternative methods that are more effective, less expensive, and environmentally friendly. One such method would be the application of preparations made from parts of the neem tree, Azadirachta indica A. Jussieu (Sapindales: Meliaceae). In this study, aqueous crude extracts and crude powder were prepared from different parts of neem, and the efficacies of the preparations on juvenile stages of Culex quinquefasciatus Say (Diptera: Culicidae) were evaluated in the laboratory. When larvae were exposed to a concentration of 0.1 g/mL extract for 24 hours, percent mean mortality (± SE) was 72.7 plusmn; 1.8 for the bark, 68.7 ± 1.6 for fruits and 60 ± 1.6 for leaves. These means were not significantly different (χ2 = 4.12; df = 2; p = 0.127). At a concentration of 0.01 g/mL, > 95% of the larvae died within 24 hours of exposure to powdered neem leaf, but it took 120 hours to reach the same level of larval mortality in aqueous leaf extract. The crude extract slowly inhibited the growth and development of mosquitoes while the crude powder acted more as a barrier; the mosquitoes probably died from suffocation. However, both types of preparations can be made and used by local people to control mosquito breeding in anthropogenic habitats, especially in urbanized areas. PMID:22233153

  6. Lack of genotoxic potential of pesticides, spinosad, imidacloprid and neem oil in mice (Mus musculus).

    PubMed

    Saxena, Ankita; Kesari, V P

    2016-03-01

    Pesticides, spinosad, imidacloprid and neem oil are widely used both in residential and agricultural environments because of its broad spectrum insecticidal activity and effectiveness. The present study was undertaken to estimate genotoxicity of formulations of some pesticides in mice. Three pesticides of diverse group studied were spinosad (45% w/v), imidacloprid (17.8%, w/v) and neem oil. Animals were exposed 37, 4.5 and 50 mg kg⁻¹ b.wt. for spinosad, imidacloprid and neem oil, respectively, through oral gavage for 5 consecutive days. A vehicle control group and one positive control (cyclophosphamide; 20 mg kg⁻¹ b. wt.) were also selected. The results showed that cyclophosphamide produced 1.12% micronuclei in mice, as against 0.18 in vehicle control, 0.30 in spinosad, 0.28 in imidacloprid and 0.22% in neem oil, respectively. The gross percentage of chromosomal aberration in mice were 28.5% in cyclophosphamide against 6.5% in vehicle control, 8.0% in spinosad, 9.5% in imidacloprid and 7.0% in neem oil, respectively. The overall findings of the present study revealed that all the three pesticide formulations, imidacloprid, spinosad and neem oil at tested dose did not show any genotoxic effect in mice.

  7. Lack of genotoxic potential of pesticides, spinosad, imidacloprid and neem oil in mice (Mus musculus).

    PubMed

    Saxena, Ankita; Kesari, V P

    2016-03-01

    Pesticides, spinosad, imidacloprid and neem oil are widely used both in residential and agricultural environments because of its broad spectrum insecticidal activity and effectiveness. The present study was undertaken to estimate genotoxicity of formulations of some pesticides in mice. Three pesticides of diverse group studied were spinosad (45% w/v), imidacloprid (17.8%, w/v) and neem oil. Animals were exposed 37, 4.5 and 50 mg kg⁻¹ b.wt. for spinosad, imidacloprid and neem oil, respectively, through oral gavage for 5 consecutive days. A vehicle control group and one positive control (cyclophosphamide; 20 mg kg⁻¹ b. wt.) were also selected. The results showed that cyclophosphamide produced 1.12% micronuclei in mice, as against 0.18 in vehicle control, 0.30 in spinosad, 0.28 in imidacloprid and 0.22% in neem oil, respectively. The gross percentage of chromosomal aberration in mice were 28.5% in cyclophosphamide against 6.5% in vehicle control, 8.0% in spinosad, 9.5% in imidacloprid and 7.0% in neem oil, respectively. The overall findings of the present study revealed that all the three pesticide formulations, imidacloprid, spinosad and neem oil at tested dose did not show any genotoxic effect in mice. PMID:27097450

  8. Effect of neem limonoids on lactate dehydrogenase (LDH) of the rice leaffolder, Cnaphalocrocis medinalis (Guenée) (Insecta: Lepidoptera: Pyralidae).

    PubMed

    Senthil Nathan, Sengottayan; Kalaivani, Kandaswamy; Chung, Paul Gene; Murugan, Kadarkarai

    2006-03-01

    Neem is derived from the neem tree Azadirachta indica A. Juss. (Meliaceae), and its primary insecticidal component is the tetranortriterpenoid azadirachtin and other limonoids. The effect of neem limonoids azadirachtin, salannin, deacetylgedunin, gedunin, 17-hydroxyazadiradione and deacetylnimbin on enzyme lactate dehydrogenase (LDH) activity of the rice leaffolder (RLF) Cnaphalocrocis medinalis (Lepidoptera: Pyralidae) larvae was investigated. There was a decrease in enzyme activity relative to the control at all concentrations tested. When fed a diet of rice leaves treated with neem limonoids in bioassays, gut tissue enzyme, LDH levels in rice leaffolder larvae are affected. These results indicate neem limonoids affect LDH activity. These effects are most pronounced in early instar larvae. Azadirachtin was the most potent in of all the limonoids in all experiments indicating strong enzyme inhibition. Clear dose-response relationships were established with respect to LDH activity. PMID:16154614

  9. The toxicity and behavioural effects of neem limonoids on Cnaphalocrocis medinalis (Guenée), the rice leaffolder.

    PubMed

    Senthil Nathan, Sengottayan; Kalaivani, Kandaswamy; Sehoon, Kim; Murugan, Kadarkarai

    2006-03-01

    Meliaceae plant products have been shown to exert pesticidal properties against a variety of insect species. In agricultural pest control programs, such products may have the potential to be used successfully as botanical insecticides. The effect of the neem (Azadirachta indica) limonoids azadirachtin, salannin, deacetylgedunin, gedunin, 17-hydroxyazadiradione and deacetylnimbin on the biology and mortality of rice leaffolder larvae was investigated. In laboratory experiments, treatment with neem limonoids suppressed leaf folding behaviour of C. medinalis. Biological parameters (larval duration, pupal duration adult longevity and fecundity) were also affected by the treatment. Azadirachtin, salannin, and deacetylgedunin showed high bioactivity at all doses, while the rest of the neem limonoids were less active, and were only biologically active at high doses. Azadirachtin was most potent in all experiments and produced almost 100% larval mortality at 1 ppm concentration. These results indicate neem limonoids affect the larval behaviour. These effects are most pronounced in early instars. PMID:16194558

  10. Medicinal properties of neem leaves: a review.

    PubMed

    Subapriya, R; Nagini, S

    2005-03-01

    Azadirachta indica, commonly known as neem, has attracted worldwide prominence in recent years, owing to its wide range of medicinal properties. Neem has been extensively used in Ayurveda, Unani and Homoeopathic medicine and has become a cynosure of modern medicine. Neem elaborates a vast array of biologically active compounds that are chemically diverse and structurally complex. More than 140 compounds have been isolated from different parts of neem. All parts of the neem tree- leaves, flowers, seeds, fruits, roots and bark have been used traditionally for the treatment of inflammation, infections, fever, skin diseases and dental disorders. The medicinal utilities have been described especially for neem leaf. Neem leaf and its constituents have been demonstrated to exhibit immunomodulatory, anti-inflammatory, antihyperglycaemic, antiulcer, antimalarial, antifungal, antibacterial, antiviral, antioxidant, antimutagenic and anticarcinogenic properties. This review summarises the wide range of pharmacological activities of neem leaf. PMID:15777222

  11. NEEM: UNUSUALLY VERSATILE PLANT GENUS AZADIRACHTA WITH MANY USEFUL AND SO FAR INSUFFICIENTLY EXPLOITED PROPERTIES FOR AGRICULTURE, MEDICINE, AND INDUSTRY.

    PubMed

    Hummel, H E; Langner, S S; Leithold, G; Schmutterer, H

    2014-01-01

    Neem plants (Rutales: Meliaceae) are well known for their multitude of human benefits in various fields. Specifically well investigated are the Indian neem tree Azadirachta indica A. Juss., the Thai neem A. siamensis Val., the originally Malaysian/Philippinean neem A. excelsa (Jack) and, as a close relative, the Persian lilac, Melia azedarach. The major and most active natural products are azadirachtin, salannin, nimbin and marrangin from Azadirachta species, and azadirachtin analogues like meliantriol from Melia species. Neem fruits, leaves, bark, and roots have specific virtues. They have been traditionally exploited for a considerable part of human history and are documented in Sanskrit texts. Due to human activity in trade and travel both at land and sea, the plant species has been distributed around the globe and is cultivated in many tropical, and subtropical regions. A multitude of natural products of neem have been isolated, chemically characterized or identified, and investigated for their properties in the management of insects, Acarina, Crustacea, nematodes, bacteria, fungi, viruses and soil fertility (for reviews see Kraus, 2002; Schmutterer, 2002A; Rembold, 2002; Koul, 2004; Schmutterer and Huber, 2005; Kleeberg and Strang, 2009; Hummel et al., 2008, 2011, 2012). Neem products are virtually nontoxic, compatible with beneficial insects, pollinators and bees. They are environmentally benign, sustainable, renewable, and of a price affordable for developed countries. In conclusion, neem is a prime example of a natural resource with many beneficial applications in agriculture, human and veterinary medicine. So far, its use is practically free of resistance problems which are frustratingly prevalent in many areas of synthetic insecticide and drug development. Investigating more neem applications will increase future human welfare and health while being of general ecological benefit to the planet. PMID:26084100

  12. NEEM: UNUSUALLY VERSATILE PLANT GENUS AZADIRACHTA WITH MANY USEFUL AND SO FAR INSUFFICIENTLY EXPLOITED PROPERTIES FOR AGRICULTURE, MEDICINE, AND INDUSTRY.

    PubMed

    Hummel, H E; Langner, S S; Leithold, G; Schmutterer, H

    2014-01-01

    Neem plants (Rutales: Meliaceae) are well known for their multitude of human benefits in various fields. Specifically well investigated are the Indian neem tree Azadirachta indica A. Juss., the Thai neem A. siamensis Val., the originally Malaysian/Philippinean neem A. excelsa (Jack) and, as a close relative, the Persian lilac, Melia azedarach. The major and most active natural products are azadirachtin, salannin, nimbin and marrangin from Azadirachta species, and azadirachtin analogues like meliantriol from Melia species. Neem fruits, leaves, bark, and roots have specific virtues. They have been traditionally exploited for a considerable part of human history and are documented in Sanskrit texts. Due to human activity in trade and travel both at land and sea, the plant species has been distributed around the globe and is cultivated in many tropical, and subtropical regions. A multitude of natural products of neem have been isolated, chemically characterized or identified, and investigated for their properties in the management of insects, Acarina, Crustacea, nematodes, bacteria, fungi, viruses and soil fertility (for reviews see Kraus, 2002; Schmutterer, 2002A; Rembold, 2002; Koul, 2004; Schmutterer and Huber, 2005; Kleeberg and Strang, 2009; Hummel et al., 2008, 2011, 2012). Neem products are virtually nontoxic, compatible with beneficial insects, pollinators and bees. They are environmentally benign, sustainable, renewable, and of a price affordable for developed countries. In conclusion, neem is a prime example of a natural resource with many beneficial applications in agriculture, human and veterinary medicine. So far, its use is practically free of resistance problems which are frustratingly prevalent in many areas of synthetic insecticide and drug development. Investigating more neem applications will increase future human welfare and health while being of general ecological benefit to the planet.

  13. Effect of Neem (Azadirachta indica) on the survival of Escherichia coli O157:H7 in dairy manure

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Escherichia coli O157:H7 (EcO157) shed in cattle manure can survive for extended periods of time and intervention strategies to control this pathogen at the source are critical as produce crops are often grown in proximity to animal raising operations. This study evaluated if Neem (Azadirachta indic...

  14. Insecticide poisoning

    MedlinePlus

    ... are breathed in. Stronger insecticides, which a commercial greenhouse might use or someone might store in their garage, contain many dangerous substances. These include: Carbamates Organophosphates Paradichlorobenzenes (mothballs)

  15. Biological detection and analysis of toxicity of organophosphate- and azadirachtin-based insecticides in Lathyrus sativus L.

    PubMed

    Ganguly, Susmita; Bhattacharya, Sima; Mandi, Sukumar; Tarafdar, Jayanta

    2010-01-01

    In this study, attention was paid to investigate the effect of organophosphate insecticides, profenofos 40% EC, methyl parathion (metacid) 50% EC, and neem-based product nimbecidine 0.03% EC (from Azadirachta indica) on somatic chromosomal behavior, level of leaf protein, and activity of antioxidant enzymes in Lathyrus sativus L., the leguminous herb. The experiments on somatic chromosomes of root tip cells of L. sativus L. revealed that most common type of abnormalities were anaphase bridge, chromosome fragment, breaks, giant interphase, etc. Also, the mitotic index reduced and abnormality index enhanced, which were directly proportional to the rise in concentration as well as time period of exposure of chemicals. The profenofos and metacid induced drastic changes in mitotic index when compared with nimbecidine. The electrophoretic studies of leaf protein of L. sativus L. showed alteration of some major and minor protein bands subjected to spraying of organophosphate insecticides and induced to synthesize additional high molecular mass protein compared to untreated control. Analysis of SOD, EST, and POD activity by non-denaturing polyacrylamide gel electrophoresis showed different patterns of the isoforms. Complete inhibition of EST was observed in profenofos-treated plants, while with metacid- and nimbecidine-treated plants EST was suppressed. Induction and/or increased activities of SOD and POD were generally enhanced. Our present study not only provides the important information for better understanding of the toxic and tolerance mechanisms, but as well can be used as a bio-indicator for contamination by pesticides, which could cause genetic instabilities of natural plant populations and in crop varieties.

  16. Biological detection and analysis of toxicity of organophosphate- and azadirachtin-based insecticides in Lathyrus sativus L.

    PubMed

    Ganguly, Susmita; Bhattacharya, Sima; Mandi, Sukumar; Tarafdar, Jayanta

    2010-01-01

    In this study, attention was paid to investigate the effect of organophosphate insecticides, profenofos 40% EC, methyl parathion (metacid) 50% EC, and neem-based product nimbecidine 0.03% EC (from Azadirachta indica) on somatic chromosomal behavior, level of leaf protein, and activity of antioxidant enzymes in Lathyrus sativus L., the leguminous herb. The experiments on somatic chromosomes of root tip cells of L. sativus L. revealed that most common type of abnormalities were anaphase bridge, chromosome fragment, breaks, giant interphase, etc. Also, the mitotic index reduced and abnormality index enhanced, which were directly proportional to the rise in concentration as well as time period of exposure of chemicals. The profenofos and metacid induced drastic changes in mitotic index when compared with nimbecidine. The electrophoretic studies of leaf protein of L. sativus L. showed alteration of some major and minor protein bands subjected to spraying of organophosphate insecticides and induced to synthesize additional high molecular mass protein compared to untreated control. Analysis of SOD, EST, and POD activity by non-denaturing polyacrylamide gel electrophoresis showed different patterns of the isoforms. Complete inhibition of EST was observed in profenofos-treated plants, while with metacid- and nimbecidine-treated plants EST was suppressed. Induction and/or increased activities of SOD and POD were generally enhanced. Our present study not only provides the important information for better understanding of the toxic and tolerance mechanisms, but as well can be used as a bio-indicator for contamination by pesticides, which could cause genetic instabilities of natural plant populations and in crop varieties. PMID:19618265

  17. Toxicity of biorational insecticides: activity against the green peach aphid, Myzus persicae (Sulzer).

    PubMed

    Edelson, Jonathan V; Duthie, J; Roberts, W

    2002-03-01

    The relationship between dose for each of four biorational insecticides (pyrethrins, neem extract, capsiacin extract, insecticidal soap) and mortality of the green peach aphid (Myzus persicae) was determined using a laboratory bioassay. These insecticides were toxic to aphids and paired mixtures of the insecticides provided synergistic activity as measured by aphid mortality under the laboratory bioassay conditions. Capsiacin extracts were found to provide low levels of mortality alone but acted synergistically in mixtures with the other insecticides and provided higher than expected levels of mortality. Activity as determined in the laboratory for each insecticide was not evident under field-use conditions in five separate experiments. Under field conditions and using common application methods, these insecticides did not provide significant levels of control of aphids.

  18. Comprehensive analyses of genomes, transcriptomes and metabolites of neem tree.

    PubMed

    Kuravadi, Nagesh A; Yenagi, Vijay; Rangiah, Kannan; Mahesh, H B; Rajamani, Anantharamanan; Shirke, Meghana D; Russiachand, Heikham; Loganathan, Ramya Malarini; Shankara Lingu, Chandana; Siddappa, Shilpa; Ramamurthy, Aishwarya; Sathyanarayana, B N; Gowda, Malali

    2015-01-01

    Neem (Azadirachta indica A. Juss) is one of the most versatile tropical evergreen tree species known in India since the Vedic period (1500 BC-600 BC). Neem tree is a rich source of limonoids, having a wide spectrum of activity against insect pests and microbial pathogens. Complex tetranortriterpenoids such as azadirachtin, salanin and nimbin are the major active principles isolated from neem seed. Absolutely nothing is known about the biochemical pathways of these metabolites in neem tree. To identify genes and pathways in neem, we sequenced neem genomes and transcriptomes using next generation sequencing technologies. Assembly of Illumina and 454 sequencing reads resulted in 267 Mb, which accounts for 70% of estimated size of neem genome. We predicted 44,495 genes in the neem genome, of which 32,278 genes were expressed in neem tissues. Neem genome consists about 32.5% (87 Mb) of repetitive DNA elements. Neem tree is phylogenetically related to citrus, Citrus sinensis. Comparative analysis anchored 62% (161 Mb) of assembled neem genomic contigs onto citrus chromomes. Ultrahigh performance liquid chromatography-mass spectrometry-selected reaction monitoring (UHPLC-MS/SRM) method was used to quantify azadirachtin, nimbin, and salanin from neem tissues. Weighted Correlation Network Analysis (WCGNA) of expressed genes and metabolites resulted in identification of possible candidate genes involved in azadirachtin biosynthesis pathway. This study provides genomic, transcriptomic and quantity of top three neem metabolites resource, which will accelerate basic research in neem to understand biochemical pathways.

  19. Comprehensive analyses of genomes, transcriptomes and metabolites of neem tree

    PubMed Central

    Rangiah, Kannan; Mahesh, HB; Rajamani, Anantharamanan; Shirke, Meghana D.; Russiachand, Heikham; Loganathan, Ramya Malarini; Shankara Lingu, Chandana; Siddappa, Shilpa; Ramamurthy, Aishwarya; Sathyanarayana, BN

    2015-01-01

    Neem (Azadirachta indica A. Juss) is one of the most versatile tropical evergreen tree species known in India since the Vedic period (1500 BC–600 BC). Neem tree is a rich source of limonoids, having a wide spectrum of activity against insect pests and microbial pathogens. Complex tetranortriterpenoids such as azadirachtin, salanin and nimbin are the major active principles isolated from neem seed. Absolutely nothing is known about the biochemical pathways of these metabolites in neem tree. To identify genes and pathways in neem, we sequenced neem genomes and transcriptomes using next generation sequencing technologies. Assembly of Illumina and 454 sequencing reads resulted in 267 Mb, which accounts for 70% of estimated size of neem genome. We predicted 44,495 genes in the neem genome, of which 32,278 genes were expressed in neem tissues. Neem genome consists about 32.5% (87 Mb) of repetitive DNA elements. Neem tree is phylogenetically related to citrus, Citrus sinensis. Comparative analysis anchored 62% (161 Mb) of assembled neem genomic contigs onto citrus chromomes. Ultrahigh performance liquid chromatography-mass spectrometry-selected reaction monitoring (UHPLC-MS/SRM) method was used to quantify azadirachtin, nimbin, and salanin from neem tissues. Weighted Correlation Network Analysis (WCGNA) of expressed genes and metabolites resulted in identification of possible candidate genes involved in azadirachtin biosynthesis pathway. This study provides genomic, transcriptomic and quantity of top three neem metabolites resource, which will accelerate basic research in neem to understand biochemical pathways. PMID:26290780

  20. Comprehensive analyses of genomes, transcriptomes and metabolites of neem tree.

    PubMed

    Kuravadi, Nagesh A; Yenagi, Vijay; Rangiah, Kannan; Mahesh, H B; Rajamani, Anantharamanan; Shirke, Meghana D; Russiachand, Heikham; Loganathan, Ramya Malarini; Shankara Lingu, Chandana; Siddappa, Shilpa; Ramamurthy, Aishwarya; Sathyanarayana, B N; Gowda, Malali

    2015-01-01

    Neem (Azadirachta indica A. Juss) is one of the most versatile tropical evergreen tree species known in India since the Vedic period (1500 BC-600 BC). Neem tree is a rich source of limonoids, having a wide spectrum of activity against insect pests and microbial pathogens. Complex tetranortriterpenoids such as azadirachtin, salanin and nimbin are the major active principles isolated from neem seed. Absolutely nothing is known about the biochemical pathways of these metabolites in neem tree. To identify genes and pathways in neem, we sequenced neem genomes and transcriptomes using next generation sequencing technologies. Assembly of Illumina and 454 sequencing reads resulted in 267 Mb, which accounts for 70% of estimated size of neem genome. We predicted 44,495 genes in the neem genome, of which 32,278 genes were expressed in neem tissues. Neem genome consists about 32.5% (87 Mb) of repetitive DNA elements. Neem tree is phylogenetically related to citrus, Citrus sinensis. Comparative analysis anchored 62% (161 Mb) of assembled neem genomic contigs onto citrus chromomes. Ultrahigh performance liquid chromatography-mass spectrometry-selected reaction monitoring (UHPLC-MS/SRM) method was used to quantify azadirachtin, nimbin, and salanin from neem tissues. Weighted Correlation Network Analysis (WCGNA) of expressed genes and metabolites resulted in identification of possible candidate genes involved in azadirachtin biosynthesis pathway. This study provides genomic, transcriptomic and quantity of top three neem metabolites resource, which will accelerate basic research in neem to understand biochemical pathways. PMID:26290780

  1. Old ingredients for a new recipe? Neem cake, a low-cost botanical by-product in the fight against mosquito-borne diseases.

    PubMed

    Benelli, Giovanni; Murugan, Kadarkarai; Panneerselvam, Chellasamy; Madhiyazhagan, Pari; Conti, Barbara; Nicoletti, Marcello

    2015-02-01

    Mosquitoes (Diptera: Culicidae) represent an important threat to millions of people worldwide, since they act as vectors for important pathogens, such as malaria, yellow fever, dengue and West Nile. Control programmes mainly rely on chemical treatments against larvae, indoor residual spraying and insecticide-treated bed nets. In recent years, huge efforts have been carried out to propose new eco-friendly alternatives, with a special focus on the evaluation of plant-borne mosquitocidal compounds. Major examples are neem-based products (Azadirachta indica A. Juss, Meliaceae) that have been proven as really effective against a huge range of pests of medical and veterinary importance, including mosquitoes. Recent research highlighted that neem cake, a cheap by-product from neem oil extraction, is an important source of mosquitocidal metabolites. In this review, we examined (i) the latest achievements about neem cake metabolomics with special reference to nor-terpenoid and related content; (ii) the neem cake ovicidal, larvicidal and pupicidal toxicity against Aedes, Anopheles and Culex mosquito vectors; (iii) its non-target effects against vertebrates; and (iv) its oviposition deterrence effects on mosquito females. Overall, neem cake can be proposed as an eco-friendly and low-cost source of chemicals to build newer and safer control tools against mosquito vectors.

  2. Effects of neem oil (Azadirachta indica A. Juss) on midgut cells of predatory larvae Ceraeochrysa claveri (Navás, 1911) (Neuroptera: Chrysopidae).

    PubMed

    Scudeler, Elton Luiz; dos Santos, Daniela Carvalho

    2013-01-01

    The effects of ingested neem oil, a botanical insecticide obtained from the seeds of the neem tree, Azadirachta indica, on the midgut cells of predatory larvae Ceraeochrysa claveri were analyzed. C. claveri were fed on eggs of Diatraea saccharalis treated with neem oil at a concentration of 0.5%, 1% and 2% during throughout the larval period. Light and electron microscopy showed severe damages in columnar cells, which had many cytoplasmic protrusions, clustering and ruptured of the microvilli, swollen cells, ruptured cells, dilatation and vesiculation of rough endoplasmic reticulum, development of smooth endoplasmic reticulum, enlargement of extracellular spaces of the basal labyrinth, intercellular spaces and necrosis. The indirect ingestion of neem oil with prey can result in severe alterations showing direct cytotoxic effects of neem oil on midgut cells of C. claveri larvae. Therefore, the safety of neem oil to non-target species as larvae of C. claveri was refuted, thus the notion that plants derived are safer to non-target species must be questioned in future ecotoxicological studies.

  3. Old ingredients for a new recipe? Neem cake, a low-cost botanical by-product in the fight against mosquito-borne diseases.

    PubMed

    Benelli, Giovanni; Murugan, Kadarkarai; Panneerselvam, Chellasamy; Madhiyazhagan, Pari; Conti, Barbara; Nicoletti, Marcello

    2015-02-01

    Mosquitoes (Diptera: Culicidae) represent an important threat to millions of people worldwide, since they act as vectors for important pathogens, such as malaria, yellow fever, dengue and West Nile. Control programmes mainly rely on chemical treatments against larvae, indoor residual spraying and insecticide-treated bed nets. In recent years, huge efforts have been carried out to propose new eco-friendly alternatives, with a special focus on the evaluation of plant-borne mosquitocidal compounds. Major examples are neem-based products (Azadirachta indica A. Juss, Meliaceae) that have been proven as really effective against a huge range of pests of medical and veterinary importance, including mosquitoes. Recent research highlighted that neem cake, a cheap by-product from neem oil extraction, is an important source of mosquitocidal metabolites. In this review, we examined (i) the latest achievements about neem cake metabolomics with special reference to nor-terpenoid and related content; (ii) the neem cake ovicidal, larvicidal and pupicidal toxicity against Aedes, Anopheles and Culex mosquito vectors; (iii) its non-target effects against vertebrates; and (iv) its oviposition deterrence effects on mosquito females. Overall, neem cake can be proposed as an eco-friendly and low-cost source of chemicals to build newer and safer control tools against mosquito vectors. PMID:25563612

  4. Potential use of neem leaf slurry as a sustainable dry season management strategy to control the malaria vector Anopheles gambiae (DIPTERA: CULICIDAE) in west African villages.

    PubMed

    Luong, Kyphuong; Dunkel, Florence V; Coulibaly, Keriba; Beckage, Nancy E

    2012-11-01

    Larval management of the malaria vector, Anopheles gambiae Giles s.s., has been successful in reducing disease transmission. However, pesticides are not affordable to farmers in remote villages in Mali, and in other material resource poor countries. Insect resistance to insecticides and nontarget toxicity pose additional problems. Neem (Azadirachta indica A. Juss) is a tree with many beneficial, insect bioactive compounds, such as azadirachtin. We tested the hypothesis that neem leaf slurry is a sustainable, natural product, anopheline larvicide. A field study conducted in Sanambele (Mali) in 2010 demonstrated neem leaf slurry can work with only the available tools and resources in the village. Laboratory bioassays were conducted with third instar An. gambiae and village methods were used to prepare the leaf slurry. Experimental concentration ranges were 1,061-21,224 mg/L pulverized neem leaves in distilled water. The 50 and 90% lethal concentrations at 72 h were 8,825 mg/L and 15,212 mg/L, respectively. LC concentrations were higher than for other parts of the neem tree when compared with previous published studies because leaf slurry preparation was simplified by omitting removal of fibrous plant tissue. Using storytelling as a medium of knowledge transfer, villagers combined available resources to manage anopheline larvae. Preparation of neem leaf slurries is a sustainable approach which allows villagers to proactively reduce mosquito larval density within their community as part of an integrated management system. PMID:23270164

  5. Effects of neem oil (Azadirachta indica A. Juss) on midgut cells of predatory larvae Ceraeochrysa claveri (Navás, 1911) (Neuroptera: Chrysopidae).

    PubMed

    Scudeler, Elton Luiz; dos Santos, Daniela Carvalho

    2013-01-01

    The effects of ingested neem oil, a botanical insecticide obtained from the seeds of the neem tree, Azadirachta indica, on the midgut cells of predatory larvae Ceraeochrysa claveri were analyzed. C. claveri were fed on eggs of Diatraea saccharalis treated with neem oil at a concentration of 0.5%, 1% and 2% during throughout the larval period. Light and electron microscopy showed severe damages in columnar cells, which had many cytoplasmic protrusions, clustering and ruptured of the microvilli, swollen cells, ruptured cells, dilatation and vesiculation of rough endoplasmic reticulum, development of smooth endoplasmic reticulum, enlargement of extracellular spaces of the basal labyrinth, intercellular spaces and necrosis. The indirect ingestion of neem oil with prey can result in severe alterations showing direct cytotoxic effects of neem oil on midgut cells of C. claveri larvae. Therefore, the safety of neem oil to non-target species as larvae of C. claveri was refuted, thus the notion that plants derived are safer to non-target species must be questioned in future ecotoxicological studies. PMID:22739123

  6. Radiosensitizing effects of neem (Azadirachta indica) oil.

    PubMed

    Kumar, Ashok; Rao, A R; Kimura, H

    2002-02-01

    Radiosensitization by neem oil was studied using Balbc/3T3 cells and SCID cells. Neem oil enhanced the radiosensitivity of the cells when applied both during and after x-irradiation under aerobic conditions. Neem oil completely inhibited the repair of sublethal damage and potentially lethal damage repair in Balbc/3T3 cells. The cytofluorimeter data show that neem oil treatment before and after x-irradiation reduced the G(2) + M phase, thus inhibiting the expression of the radiation induced arrest of cells in the G(2) phase of the cell cycle. However, SCIK cells (derived from the SCID mouse), deficient in DSB repair, treated with neem oil did not show any enhancement in the radiosensitivity. There was no effect of neem oil on SLD repair or its inhibition in SCIK cells. These results suggest that neem oil enhanced the radiosensitivity of cells by interacting with residual damage after x-irradiation, thereby converting the sublethal damage or potentially lethal damage into lethal damage, inhibiting the double-strand break repair or reducing the G(2) phase of the cell cycle. PMID:11807971

  7. The toxicity of margosan-O, a product of neem seeds, to selected target and nontarget aquatic invertebrates

    PubMed

    Scott; Kaushik

    1998-10-01

    Margosan-O, an insecticide formulated from extracts of neem tree (Azadirachta indica) seed kernels, besides being toxic, also has feeding, oviposition-deterring, and growth-inhibitory effects on insects. This product, registered in the United States for ornamental plants, has been proposed for food crop use. However, little information exists on its effects on aquatic organisms. This study investigated toxicity of Margosan-O to the mosquito Culex spp., a possible target species, and to nontarget species-two crustaceans, Daphnia magna, Hyalella azteca, and a dipteran, Chironomus riparius. The 48-h EC50 value of 105 mg L-1 for Culex spp. was significantly more toxic than for C. riparius (281 mg L-1), not significantly different from D. magna (125 mg L-1) but was significantly less toxic than for H. azteca (71 mg L-1). A concentration of 20-30 mg L-1 caused growth inhibitory effects in Culex spp. and C. riparius larvae and 40 and 84 mg L-1 affected growth and reproduction in H. azteca and D. magna, respectively. Margosan-O may not be suitable for mosquito control since the concentrations required to control emergence may have some nontarget effects. Alternatively, the agricultural application of Margosan-O is also not expected to reduce the survival or produce growth and reproductive effects in nontarget aquatic organisms. However, based on estimated concentrations of less than 10 mg L-1 in adjacent shallow bodies of water and recommendations for repeated applications, there should be concern that the threshold for chronic toxicity is too narrow. PMID:9732473

  8. Mechanism of antifertility action of neem oil.

    PubMed

    Riar, S S; Bardhan, J; Thomas, P; Kain, A K; Parshad, R

    1988-10-01

    The purpose of this study was to determine whether the antifertility effect of the antiestrogenic substance neem oil, extracted from the seeds of Azadirachta indica, acts directly on the uterus or through absorption from the vaginal epithelium into the general circulation. In 4 groups of rats the left uterine horn was ligated 2 days after coitus. Rats in group A were used as controls. In group B 25 mcl neem oil was administered intravaginally on days 2-4 with the animals in head down position for 3 minutes to ensure that the neem oil was uniformly distributed in the vagina. In group C the neem oil was administered on days 4-6, and in group D on days 7-9, i.e., after implantation. The ligatures were removed on day 12, and no viable implantation sites were found in either horn. The study showed that the neem oil exerts its effect on the endometrium through absorption into the general circulation from the vaginal epithelium. The antiestrogenic quality of neem oil explains its anti-implantation effect. But the postimplantation effect, which caused implanted fetuses to be either resorbed or expelled, may be due to direct toxicity, to a fall in progesterone level, or to interference with the uterine utilization of progesterone. PMID:3225018

  9. Toxic effects of neem cake extracts on Aedes albopictus (Skuse) larvae.

    PubMed

    Nicoletti, Marcello; Serafini, Mauro; Aliboni, Andrea; D'Andrea, Armando; Mariani, Susanna

    2010-06-01

    In order to investigate its insecticide potential, the neem cake methanol extract was first analyzed and then separated by different solvents. The high-performance liquid chromatography analysis showed that the neem cake methanol extract still contained relevant quantities of nortriterpenes. Fractions of increasing polarity were obtained from the separation process: hexane fraction (Hp), EtOAc fraction (Ep), n-BuOH fraction (Bp), and aqueous fraction (Wp). The activity of the fractions on Aedes albopictus (Skuse) eggs and larvae was tested, and the Ep fraction exhibits the most relevant larvicide effect. The nuclear magnetic resonance fingerprint analysis of this phytocomplex isolated on EtOAc fraction was performed. The larvicidal effectiveness of the phytocomplex isolated on EtOAc, compared to that of pure and commercial azadirachtin solutions of different concentrations, was checked. The results showed that the activity of the phytocomplex, as a whole, was significantly higher than those of isolated compound solutions. As a consequence, the neem cake is a promising low-cost, easily available on the market, and natural resource to develop a new bioinsecticide, mainly in developing countries.

  10. A new shampoo based on neem (Azadirachta indica) is highly effective against head lice in vitro.

    PubMed

    Heukelbach, Jörg; Oliveira, Fabíola A S; Speare, Richard

    2006-09-01

    Because topical compounds based on insecticidal chemicals are the mainstay of head lice treatment, but resistance is increasing, alternatives, such as herbs and oils are being sold to treat head lice. To test a commercial shampoo based on seed extract of Azadirachta indica (neem tree) for its in vitro effect, head lice (n=17) were collected from school children in Australia and immersed in Wash-Away Louse shampoo (Alpha-Biocare GmbH, Germany). Vitality was evaluated for more than 3 h by examination under a dissecting microscope. Positive and negative controls were a commercially available head lice treatment containing permethrin 1% (n=19) and no treatment (n=14). All lice treated with the neem shampoo did not show any vital signs from the initial examination after immersion at 5-30 min; after 3 h, only a single louse showed minor signs of life, indicated by gut movements, a mortality of 94%. In the permethrin group, mortality was 20% at 5 min, 50% at 15 min, and 74% after 3 h. All 14 head lice of the negative control group survived during the observation period. Our data show that Wash-Away Louse is highly effective in vitro against head lice. The neem shampoo was more effective than the permethrin-based product. We speculate that complex plant-based compounds will replace the well-defined chemical pediculicides if resistance to the commonly used products further increases.

  11. Selectivity of neem to Trichogramma pretiosum Riley and Trichogrammatoidea annulata De Santis (Hymenoptera: Trichogrammatidae).

    PubMed

    Hohmann, Celso L; Silva, Flávia A C; Novaes, Tanara G de

    2010-01-01

    Trichogramma pretiosum Riley and Trichogrammatoidea annulata De Santis are commonly found in avocado and persimmon orchards in northern Parana state. However, their abundance depends on whether insecticides are used or not to control the key lepidopteran pests Stenoma catenifer (Wals.) (Lepidoptera: Elachistidae) and Hypocala andremona (Stoll) (Lepidoptera: Noctuidae), respectively. The aim of this work was to evaluate the effects of an aqueous neem seed extract (ANSE) at 15, 3 and 1.5%, and of an emulsifiable concentrate neem oil (ECNO) at 2.5, 0.5 and 0.25% on lifetime parameters of these trichogrammatids as a way of testing the feasibility of integrating the biological and chemical control methods. Chemicals were applied on Anagasta kuehniella (Zeller) (Lepidoptera: Pyralidae) eggs before or after parasitization (one, three or five days). ANSE was more deleterious to both parasitoid species than ECNO, regardless of the concentration and the time of application. The chemicals acted on a concentration and time dependent manner. Treating the host with neem before parasitism was less deleterious to wasp emergence, especially for T. annulata. Pre-treatments (24h) of the host eggs with ECNO at concentrations varying from 0.5% to 0.25% did not affect T. pretiosum longevity, but 2.5% reduced T. annulata survival. Feeding wasps with honey mixed with 0.25% ECNO negatively affected T. annulata survival.

  12. A new shampoo based on neem (Azadirachta indica) is highly effective against head lice in vitro.

    PubMed

    Heukelbach, Jörg; Oliveira, Fabíola A S; Speare, Richard

    2006-09-01

    Because topical compounds based on insecticidal chemicals are the mainstay of head lice treatment, but resistance is increasing, alternatives, such as herbs and oils are being sold to treat head lice. To test a commercial shampoo based on seed extract of Azadirachta indica (neem tree) for its in vitro effect, head lice (n=17) were collected from school children in Australia and immersed in Wash-Away Louse shampoo (Alpha-Biocare GmbH, Germany). Vitality was evaluated for more than 3 h by examination under a dissecting microscope. Positive and negative controls were a commercially available head lice treatment containing permethrin 1% (n=19) and no treatment (n=14). All lice treated with the neem shampoo did not show any vital signs from the initial examination after immersion at 5-30 min; after 3 h, only a single louse showed minor signs of life, indicated by gut movements, a mortality of 94%. In the permethrin group, mortality was 20% at 5 min, 50% at 15 min, and 74% after 3 h. All 14 head lice of the negative control group survived during the observation period. Our data show that Wash-Away Louse is highly effective in vitro against head lice. The neem shampoo was more effective than the permethrin-based product. We speculate that complex plant-based compounds will replace the well-defined chemical pediculicides if resistance to the commonly used products further increases. PMID:16568334

  13. Selectivity of neem to Trichogramma pretiosum Riley and Trichogrammatoidea annulata De Santis (Hymenoptera: Trichogrammatidae).

    PubMed

    Hohmann, Celso L; Silva, Flávia A C; Novaes, Tanara G de

    2010-01-01

    Trichogramma pretiosum Riley and Trichogrammatoidea annulata De Santis are commonly found in avocado and persimmon orchards in northern Parana state. However, their abundance depends on whether insecticides are used or not to control the key lepidopteran pests Stenoma catenifer (Wals.) (Lepidoptera: Elachistidae) and Hypocala andremona (Stoll) (Lepidoptera: Noctuidae), respectively. The aim of this work was to evaluate the effects of an aqueous neem seed extract (ANSE) at 15, 3 and 1.5%, and of an emulsifiable concentrate neem oil (ECNO) at 2.5, 0.5 and 0.25% on lifetime parameters of these trichogrammatids as a way of testing the feasibility of integrating the biological and chemical control methods. Chemicals were applied on Anagasta kuehniella (Zeller) (Lepidoptera: Pyralidae) eggs before or after parasitization (one, three or five days). ANSE was more deleterious to both parasitoid species than ECNO, regardless of the concentration and the time of application. The chemicals acted on a concentration and time dependent manner. Treating the host with neem before parasitism was less deleterious to wasp emergence, especially for T. annulata. Pre-treatments (24h) of the host eggs with ECNO at concentrations varying from 0.5% to 0.25% did not affect T. pretiosum longevity, but 2.5% reduced T. annulata survival. Feeding wasps with honey mixed with 0.25% ECNO negatively affected T. annulata survival. PMID:21271068

  14. Insecticidal properties of a Chenopodium-based botanical.

    PubMed

    Chiasson, H; Vincent, C; Bostanian, N J

    2004-08-01

    The emulsifiable concentrate UDA-245 based on an essential oil extract from Chenopodium ambrosioides variety near ambrosioides, a North American herbaceous plant, was compared with commercially available pesticides for their effectiveness to control green peach aphid, Myzus persicae (Sulzer) (Homoptera: Aphididae), western flower thrips, Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), and greenhouse whitefly, Trialeurodes vaporariorium (Westwood) (Homoptera: Aleyrodidae). Side effects on the whitefly parasitoid Encarsia formosa Gahan (Hymenoptera: Aphelinidae) also were determined. With green peach aphid, UDA-245 at 0.5% concentration was significantly more effective than the control (water) treatment in a laboratory bioassay and significantly more effective than neem oil and the control treatment and as effective as insecticidal soap in a greenhouse assay. With the western flower thrips, UDA-245 at 0.5% was significantly more effective than neem oil, insecticidal soap and the control treatment in a laboratory bioassay, whereas in a greenhouse assay, UDA-245 at 1.0% was the only treatment that maintained control of the western flower thrips 2 wk after the last treatment period. UDA-245 at 0.5% (laboratory bioassay) was significantly more effective in managing greenhouse whitefly than neem oil, endosulfan, and the control treatment and as effective as insecticidal soap. Insecticidal soap proved to be toxic to the parasitoid E. formosa (71.9% mortality), whereas UDA-245 at 0.5% was not significantly more toxic than the control (11.2 and 4.6% mortality, respectively). Our results suggest that a greenhouse integrated pest management (IPM) program using a botanical such as UDA-245 could effectively control infestations of major pests present while having a negligible effect on biological control agents.

  15. Insecticidal properties of a Chenopodium-based botanical.

    PubMed

    Chiasson, H; Vincent, C; Bostanian, N J

    2004-08-01

    The emulsifiable concentrate UDA-245 based on an essential oil extract from Chenopodium ambrosioides variety near ambrosioides, a North American herbaceous plant, was compared with commercially available pesticides for their effectiveness to control green peach aphid, Myzus persicae (Sulzer) (Homoptera: Aphididae), western flower thrips, Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), and greenhouse whitefly, Trialeurodes vaporariorium (Westwood) (Homoptera: Aleyrodidae). Side effects on the whitefly parasitoid Encarsia formosa Gahan (Hymenoptera: Aphelinidae) also were determined. With green peach aphid, UDA-245 at 0.5% concentration was significantly more effective than the control (water) treatment in a laboratory bioassay and significantly more effective than neem oil and the control treatment and as effective as insecticidal soap in a greenhouse assay. With the western flower thrips, UDA-245 at 0.5% was significantly more effective than neem oil, insecticidal soap and the control treatment in a laboratory bioassay, whereas in a greenhouse assay, UDA-245 at 1.0% was the only treatment that maintained control of the western flower thrips 2 wk after the last treatment period. UDA-245 at 0.5% (laboratory bioassay) was significantly more effective in managing greenhouse whitefly than neem oil, endosulfan, and the control treatment and as effective as insecticidal soap. Insecticidal soap proved to be toxic to the parasitoid E. formosa (71.9% mortality), whereas UDA-245 at 0.5% was not significantly more toxic than the control (11.2 and 4.6% mortality, respectively). Our results suggest that a greenhouse integrated pest management (IPM) program using a botanical such as UDA-245 could effectively control infestations of major pests present while having a negligible effect on biological control agents. PMID:15384351

  16. Efficacy and Dose Response of Soil-Applied Neem Formulations in Substrates With Different Amounts of Organic Matter, in the Control of Whiteflies, Aleyrodes proletella and Trialeurodes vaporariorum (Hemiptera: Aleyrodidae).

    PubMed

    Karanja, Josephine; Poehling, Hans-Michael; Pallmann, Philip

    2015-06-01

    Neem products have been used frequently as an alternative to synthetic pesticides, because of their insecticidal, insect antifeedant, and growth-regulating effects. Moreover, new formulations are continually being developed and therefore, they have to be evaluated for their efficacy and persistence. In this regard, two soil-applied products-a liquid-based drenching solution NeemAzal-T and NeemAzal granules-were evaluated against two whitefly species, Aleyrodes proletella L. and Trialeurodes vaporariorum (West) on Brussels sprout and tomatoes, respectively. The plants were grown in two substrates: one was a commercial substrate (CS) composed of 15% humus, 35% clay, and 50% peat, and the other was a commercial substrate and sand mixture in 1:1 ratio. The main objective of the study was to evaluate the efficacy, persistence, and dose response of the two soil-applied NeemAzal formulations in substrates with different amount of organic matter. The results show that the efficacy of neem formulations was dose dependent, with the highest doses of NeemAzal granules (300 mg/kg=21 mg azadirachtin [AZA]/kg of substrate) and NeemAzal T (2 ml/kg=20 mg AZA/kg of substrate) achieving up to 100% mortality of immature stages of whiteflies. NeemAzal caused significantly higher mortality in immature stages of both whitefly species with CS + sand mixture than with pure CS. Persistence of the NeemAzal formulations was not influenced by the substrate type but rather by time span between treatment application and infestation, with significant decrease in efficacy when whiteflies were exposed 10 d after treatments. PMID:26470244

  17. Efficacy and Dose Response of Soil-Applied Neem Formulations in Substrates With Different Amounts of Organic Matter, in the Control of Whiteflies, Aleyrodes proletella and Trialeurodes vaporariorum (Hemiptera: Aleyrodidae).

    PubMed

    Karanja, Josephine; Poehling, Hans-Michael; Pallmann, Philip

    2015-06-01

    Neem products have been used frequently as an alternative to synthetic pesticides, because of their insecticidal, insect antifeedant, and growth-regulating effects. Moreover, new formulations are continually being developed and therefore, they have to be evaluated for their efficacy and persistence. In this regard, two soil-applied products-a liquid-based drenching solution NeemAzal-T and NeemAzal granules-were evaluated against two whitefly species, Aleyrodes proletella L. and Trialeurodes vaporariorum (West) on Brussels sprout and tomatoes, respectively. The plants were grown in two substrates: one was a commercial substrate (CS) composed of 15% humus, 35% clay, and 50% peat, and the other was a commercial substrate and sand mixture in 1:1 ratio. The main objective of the study was to evaluate the efficacy, persistence, and dose response of the two soil-applied NeemAzal formulations in substrates with different amount of organic matter. The results show that the efficacy of neem formulations was dose dependent, with the highest doses of NeemAzal granules (300 mg/kg=21 mg azadirachtin [AZA]/kg of substrate) and NeemAzal T (2 ml/kg=20 mg AZA/kg of substrate) achieving up to 100% mortality of immature stages of whiteflies. NeemAzal caused significantly higher mortality in immature stages of both whitefly species with CS + sand mixture than with pure CS. Persistence of the NeemAzal formulations was not influenced by the substrate type but rather by time span between treatment application and infestation, with significant decrease in efficacy when whiteflies were exposed 10 d after treatments.

  18. Neem oil limonoids induces p53-independent apoptosis and autophagy.

    PubMed

    Srivastava, Pragya; Yadav, Neelu; Lella, Ravi; Schneider, Andrea; Jones, Anthony; Marlowe, Timothy; Lovett, Gabrielle; O'Loughlin, Kieran; Minderman, Hans; Gogada, Raghu; Chandra, Dhyan

    2012-11-01

    Azadirachta indica, commonly known as neem, has a wide range of medicinal properties. Neem extracts and its purified products have been examined for induction of apoptosis in multiple cancer cell types; however, its underlying mechanisms remain undefined. We show that neem oil (i.e., neem), which contains majority of neem limonoids including azadirachtin, induced apoptotic and autophagic cell death. Gene silencing demonstrated that caspase cascade was initiated by the activation of caspase-9, whereas caspase-8 was also activated late during neem-induced apoptosis. Pretreatment of cancer cells with pan caspase inhibitor, z-VAD inhibited activities of both initiator caspases (e.g., caspase-8 and -9) and executioner caspase-3. Neem induced the release of cytochrome c and apoptosis-inducing factor (AIF) from mitochondria, suggesting the involvement of both caspase-dependent and AIF-mediated apoptosis. p21 deficiency caused an increase in caspase activities at lower doses of neem, whereas p53 deficiency did not modulate neem-induced caspase activation. Additionally, neem treatment resulted in the accumulation of LC3-II in cancer cells, suggesting the involvement of autophagy in neem-induced cancer cell death. Low doses of autophagy inhibitors (i.e., 3-methyladenine and LY294002) did not prevent accumulation of neem-induced LC3-II in cancer cells. Silencing of ATG5 or Beclin-1 further enhanced neem-induced cell death. Phosphoinositide 3-kinase (PI3K) or autophagy inhibitors increased neem-induced caspase-3 activation and inhibition of caspases enhanced neem-induced autophagy. Together, for the first time, we demonstrate that neem induces caspase-dependent and AIF-mediated apoptosis, and autophagy in cancer cells.

  19. Neem oil limonoids induces p53-independent apoptosis and autophagy.

    PubMed

    Srivastava, Pragya; Yadav, Neelu; Lella, Ravi; Schneider, Andrea; Jones, Anthony; Marlowe, Timothy; Lovett, Gabrielle; O'Loughlin, Kieran; Minderman, Hans; Gogada, Raghu; Chandra, Dhyan

    2012-11-01

    Azadirachta indica, commonly known as neem, has a wide range of medicinal properties. Neem extracts and its purified products have been examined for induction of apoptosis in multiple cancer cell types; however, its underlying mechanisms remain undefined. We show that neem oil (i.e., neem), which contains majority of neem limonoids including azadirachtin, induced apoptotic and autophagic cell death. Gene silencing demonstrated that caspase cascade was initiated by the activation of caspase-9, whereas caspase-8 was also activated late during neem-induced apoptosis. Pretreatment of cancer cells with pan caspase inhibitor, z-VAD inhibited activities of both initiator caspases (e.g., caspase-8 and -9) and executioner caspase-3. Neem induced the release of cytochrome c and apoptosis-inducing factor (AIF) from mitochondria, suggesting the involvement of both caspase-dependent and AIF-mediated apoptosis. p21 deficiency caused an increase in caspase activities at lower doses of neem, whereas p53 deficiency did not modulate neem-induced caspase activation. Additionally, neem treatment resulted in the accumulation of LC3-II in cancer cells, suggesting the involvement of autophagy in neem-induced cancer cell death. Low doses of autophagy inhibitors (i.e., 3-methyladenine and LY294002) did not prevent accumulation of neem-induced LC3-II in cancer cells. Silencing of ATG5 or Beclin-1 further enhanced neem-induced cell death. Phosphoinositide 3-kinase (PI3K) or autophagy inhibitors increased neem-induced caspase-3 activation and inhibition of caspases enhanced neem-induced autophagy. Together, for the first time, we demonstrate that neem induces caspase-dependent and AIF-mediated apoptosis, and autophagy in cancer cells. PMID:22915764

  20. Three new tetranortriterpenoids from neem seed oil.

    PubMed

    Hallur, Gurulingappa; Sivramakrishnan, Apoorba; Bhat, Sujata V

    2002-08-01

    Three new tetranortriterpenoids, 1alpha,2alpha-epoxy-17beta-hydroxyazadiradione (1), 1alpha,2alpha-epoxynimolicinol (2), and 7-deacetylnimolicinol (3), have been isolated from a methanol extract of neem oil (Azadirachta indica, seed oil) along with the known compounds epoxyazadiradione, 17beta-hydroxyazadiradione, gedunin, nimbin, and nimolicinol (4). Spectral studies and chemical transformations were used to establish the structure of compounds 1-3. The characterization of the epoxides 1 and 2 in neem oil is of biogenetic significance, as they may be considered as intermediates between A-ring enones and 1,3-diols among the A. indica tetranortriterpenoids. PMID:12193026

  1. Metals bioaccumulation mechanism in neem bark

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The aim of this work was to define the bioaccumulation mechanism of metals onto the non-living biomaterial prepared from an extensively available plant bark biomass of neem (Azadirachta indica). Based on maximum ultimate fixation capacities (mmol/g) of the product, metals ions could be arranged as H...

  2. Effect of pest controlling neem and mata-raton leaf extracts on greenhouse gas emissions from urea-amended soil cultivated with beans: a greenhouse experiment.

    PubMed

    Méndez-Bautista, Joaquín; Fernández-Luqueño, Fabián; López-Valdez, Fernando; Mendoza-Cristino, Reyna; Montes-Molina, Joaquín A; Gutierrez-Miceli, Federico A; Dendooven, L

    2010-10-01

    In a previous laboratory experiment, extracts of neem (Azadirachta indica A. Juss.) and Gliricidia sepium Jacquin, locally known as mata-raton, used to control pests on crops, inhibited emissions of CO(2) from a urea-amended soil, but not nitrification and N(2)O emissions. We investigated if these extracts when applied to beans (Phaseolus vulgaris L.) affected their development, soil characteristics and emissions of carbon dioxide (CO(2)) and nitrous oxide (N(2)O) in a greenhouse environment. Untreated beans and beans planted with lambda-cyhalothrin, a commercial insecticide, served as controls. After 117days, shoots of plants cultivated in soil amended with urea or treated with lambda-cyhalothrin, or extracts of neem or G. sepium were significantly higher than when cultivated in the unamended soil, while the roots were significantly longer when plants were amended with urea or treated with leaf extracts of neem or G. sepium than when treated with lambda-cyhalothrin. The number of pods, fresh and dry pod weight and seed yield was significantly higher when bean plants were treated with leaf extracts of neem or G. sepium treatments than when left untreated and unfertilized. The number of seeds was similar for the different treatments. The number of nodules was lower in plants fertilized with urea, treated with leaf extracts of neem or G. sepium, or with lambda-cyhalothrin compared to the unfertilized plants. The concentrations of NH(4)(+), NO(2)(-) and NO(3)(-) decreased significantly over time with the lowest concentrations generally found at harvest. Treatment had no significant effect on the concentrations of NH(4)(+) and NO(2)(-), but the concentration of NO(3)(-) was significantly lower in the unfertilized soil compared to the other treatments. It was found that applying extracts of neem or G. sepium leaves to beans favored their development when compared to untreated plants, but had no significant effect on nitrification in soil.

  3. Effect of pest controlling neem and mata-raton leaf extracts on greenhouse gas emissions from urea-amended soil cultivated with beans: a greenhouse experiment.

    PubMed

    Méndez-Bautista, Joaquín; Fernández-Luqueño, Fabián; López-Valdez, Fernando; Mendoza-Cristino, Reyna; Montes-Molina, Joaquín A; Gutierrez-Miceli, Federico A; Dendooven, L

    2010-10-01

    In a previous laboratory experiment, extracts of neem (Azadirachta indica A. Juss.) and Gliricidia sepium Jacquin, locally known as mata-raton, used to control pests on crops, inhibited emissions of CO(2) from a urea-amended soil, but not nitrification and N(2)O emissions. We investigated if these extracts when applied to beans (Phaseolus vulgaris L.) affected their development, soil characteristics and emissions of carbon dioxide (CO(2)) and nitrous oxide (N(2)O) in a greenhouse environment. Untreated beans and beans planted with lambda-cyhalothrin, a commercial insecticide, served as controls. After 117days, shoots of plants cultivated in soil amended with urea or treated with lambda-cyhalothrin, or extracts of neem or G. sepium were significantly higher than when cultivated in the unamended soil, while the roots were significantly longer when plants were amended with urea or treated with leaf extracts of neem or G. sepium than when treated with lambda-cyhalothrin. The number of pods, fresh and dry pod weight and seed yield was significantly higher when bean plants were treated with leaf extracts of neem or G. sepium treatments than when left untreated and unfertilized. The number of seeds was similar for the different treatments. The number of nodules was lower in plants fertilized with urea, treated with leaf extracts of neem or G. sepium, or with lambda-cyhalothrin compared to the unfertilized plants. The concentrations of NH(4)(+), NO(2)(-) and NO(3)(-) decreased significantly over time with the lowest concentrations generally found at harvest. Treatment had no significant effect on the concentrations of NH(4)(+) and NO(2)(-), but the concentration of NO(3)(-) was significantly lower in the unfertilized soil compared to the other treatments. It was found that applying extracts of neem or G. sepium leaves to beans favored their development when compared to untreated plants, but had no significant effect on nitrification in soil. PMID:20692019

  4. Neem components as potential agents for cancer prevention and treatment.

    PubMed

    Hao, Fang; Kumar, Sandeep; Yadav, Neelu; Chandra, Dhyan

    2014-08-01

    Azadirachta indica, also known as neem, is commonly found in many semi-tropical and tropical countries including India, Pakistan, and Bangladesh. The components extracted from neem plant have been used in traditional medicine for the cure of multiple diseases including cancer for centuries. The extracts of seeds, leaves, flowers, and fruits of neem have consistently shown chemopreventive and antitumor effects in different types of cancer. Azadirachtin and nimbolide are among the few bioactive components in neem that have been studied extensively, but research on a great number of additional bioactive components is warranted. The key anticancer effects of neem components on malignant cells include inhibition of cell proliferation, induction of cell death, suppression of cancer angiogenesis, restoration of cellular reduction/oxidation (redox) balance, and enhancement of the host immune responses against tumor cells. While the underlying mechanisms of these effects are mostly unclear, the suppression of NF-κB signaling pathway is, at least partially, involved in the anticancer functions of neem components. Importantly, the anti-proliferative and apoptosis-inducing effects of neem components are tumor selective as the effects on normal cells are significantly weaker. In addition, neem extracts sensitize cancer cells to immunotherapy and radiotherapy, and enhance the efficacy of certain cancer chemotherapeutic agents. This review summarizes the current updates on the anticancer effects of neem components and their possible impact on managing cancer incidence and treatment. PMID:25016141

  5. Neem components as potential agents for cancer prevention and treatment.

    PubMed

    Hao, Fang; Kumar, Sandeep; Yadav, Neelu; Chandra, Dhyan

    2014-08-01

    Azadirachta indica, also known as neem, is commonly found in many semi-tropical and tropical countries including India, Pakistan, and Bangladesh. The components extracted from neem plant have been used in traditional medicine for the cure of multiple diseases including cancer for centuries. The extracts of seeds, leaves, flowers, and fruits of neem have consistently shown chemopreventive and antitumor effects in different types of cancer. Azadirachtin and nimbolide are among the few bioactive components in neem that have been studied extensively, but research on a great number of additional bioactive components is warranted. The key anticancer effects of neem components on malignant cells include inhibition of cell proliferation, induction of cell death, suppression of cancer angiogenesis, restoration of cellular reduction/oxidation (redox) balance, and enhancement of the host immune responses against tumor cells. While the underlying mechanisms of these effects are mostly unclear, the suppression of NF-κB signaling pathway is, at least partially, involved in the anticancer functions of neem components. Importantly, the anti-proliferative and apoptosis-inducing effects of neem components are tumor selective as the effects on normal cells are significantly weaker. In addition, neem extracts sensitize cancer cells to immunotherapy and radiotherapy, and enhance the efficacy of certain cancer chemotherapeutic agents. This review summarizes the current updates on the anticancer effects of neem components and their possible impact on managing cancer incidence and treatment.

  6. Neem oil: an herbal therapy for alopecia causes dermatitis.

    PubMed

    Reutemann, Patricia; Ehrlich, Alison

    2008-01-01

    For more than 2,000 years, the neem tree has been considered one of the most useful and versatile plants in the world. Neem oil has been used for both homeopathic remedies and as a pesticide. Both systemic and contact reactions have occurred with the use of neem oil. We report a patient who presented with an acute case of contact dermatitis on the scalp and face after the use of neem oil for alopecia and present a review of the literature regarding its uses, toxicity, and regulation. PMID:18627678

  7. Neem components as potential agents for cancer prevention and treatment

    PubMed Central

    Hao, Fang; Kumar, Sandeep; Yadav, Neelu; Chandra, Dhyan

    2016-01-01

    Azadirachta indica, also known as neem, is commonly found in many semi-tropical and tropical countries including India, Pakistan, and Bangladesh. The components extracted from neem plant have been used in traditional medicine for the cure of multiple diseases including cancer for centuries. The extracts of seeds, leaves, flowers, and fruits of neem have consistently shown chemopreventive and antitumor effects in different types of cancer. Azadirachtin and nimbolide are among the few bioactive components in neem that have been studied extensively, but research on a great number of additional bioactive components is warranted. The key anticancer effects of neem components on malignant cells include inhibition of cell proliferation, induction of cell death, suppression of cancer angiogenesis, restoration of cellular reduction/oxidation (redox) balance, and enhancement of the host immune responses against tumor cells. While the underlying mechanisms of these effects are mostly unclear, the suppression of NF-κB signaling pathway is, at least partially, involved in the anticancer functions of neem components. Importantly, the anti-proliferative and apoptosis-inducing effects of neem components are tumor selective as the effects on normal cells are significantly weaker. In addition, neem extracts sensitize cancer cells to immunotherapy and radiotherapy, and enhance the efficacy of certain cancer chemotherapeutic agents. This review summarizes the current updates on the anticancer effects of neem components and their possible impact on managing cancer incidence and treatment. PMID:25016141

  8. ESolvent-free, enzyme-catalyzed biodiesel production from mango, neem, and shea oils via response surface methodology.

    PubMed

    Nde, Divine Bup; Astete, Carlos; Boldor, Dorin

    2015-12-01

    Mango, neem and shea kernels produce non-conventional oils whose potentials are not fully exploited. To give an added value to these oils, they were transesterified into biodiesel in a solvent-free system using immobilized enzyme lipozyme from Mucor miehei. The Doehlert experimental design was used to evaluate the methyl ester (ME) yields as influenced by enzyme concentration-EC, temperature-T, added water content-AWC, and reaction time-RT. Biodiesel yields were quantified by (1)H NMR spectroscopy and subsequently modeled by a second order polynomial equation with interactions. Lipozyme enzymes were more tolerant to high temperatures in neem and shea oils reaction media compared to that of mango oil. The optimum reaction conditions EC, T, AWC, and RT assuring near complete conversion were as follows: mango oil 7.25 %, 36.6 °C, 10.9 %, 36.4 h; neem oil EC = 7.19 %, T = 45.7 °C, AWC = 8.43 %, RT = 25.08 h; and shea oil EC = 4.43 %, T = 45.65 °C, AWC = 6.21 % and RT = 25.08 h. Validation experiments of these optimum conditions gave ME yields of 98.1 ± 1.0, 98.5 ± 1.6 and 99.3 ± 0.4 % for mango, neem and shea oils, respectively, which all met ASTM biodiesel standards. PMID:26698315

  9. ESolvent-free, enzyme-catalyzed biodiesel production from mango, neem, and shea oils via response surface methodology.

    PubMed

    Nde, Divine Bup; Astete, Carlos; Boldor, Dorin

    2015-12-01

    Mango, neem and shea kernels produce non-conventional oils whose potentials are not fully exploited. To give an added value to these oils, they were transesterified into biodiesel in a solvent-free system using immobilized enzyme lipozyme from Mucor miehei. The Doehlert experimental design was used to evaluate the methyl ester (ME) yields as influenced by enzyme concentration-EC, temperature-T, added water content-AWC, and reaction time-RT. Biodiesel yields were quantified by (1)H NMR spectroscopy and subsequently modeled by a second order polynomial equation with interactions. Lipozyme enzymes were more tolerant to high temperatures in neem and shea oils reaction media compared to that of mango oil. The optimum reaction conditions EC, T, AWC, and RT assuring near complete conversion were as follows: mango oil 7.25 %, 36.6 °C, 10.9 %, 36.4 h; neem oil EC = 7.19 %, T = 45.7 °C, AWC = 8.43 %, RT = 25.08 h; and shea oil EC = 4.43 %, T = 45.65 °C, AWC = 6.21 % and RT = 25.08 h. Validation experiments of these optimum conditions gave ME yields of 98.1 ± 1.0, 98.5 ± 1.6 and 99.3 ± 0.4 % for mango, neem and shea oils, respectively, which all met ASTM biodiesel standards.

  10. ECS communications success

    NASA Astrophysics Data System (ADS)

    Dinwiddy, S. E.

    1985-09-01

    The European Communications Satellite (ECS) which supplies satellite links for national telecommunication, long-distance international telephone traffic, and the distribution of television programs is described. The ECS concept was tested by the Orbital Test Satellite and proved the applicability of the ECS for television transmission and high-speed data links provided by small earth stations. The industrial development, operation, and cost of the project, which was shared by the European Space Agency members, are discussed. Extra repeater chains for small-dish services employed by ECS operate in the 14.0-14.25 GHz uplink and 12.5-12.75 GHz downlink frequency band and are utilized by small earth stations. The advantages and disadvantages of transmission services provided by the small earth stations are studied. The utilization of the point-to-multipoint service of the small earth station for the transmission of data is analyzed. The television distribution services available with the ECS system are examined; the ECS provides ten 20-W channels for a lifetime of seven years.

  11. Side Effects of Neem Oil on the Midgut Endocrine Cells of the Green Lacewing Ceraeochrysa claveri (Navás) (Neuroptera: Chrysopidae).

    PubMed

    Scudeler, E L; Santos, D C

    2014-04-01

    We described the ultrastructure of Ceraeochrysa claveri (Navás) midgut endocrine cells in larva, pupa, and adult, and evaluated the side effects of ingested neem oil, a botanical insecticide obtained from the seeds of the neem tree (Azadirachta indica), on these cells. During the larval period, C. claveri were fed (ad libitum) Diatraea saccharalis (F.) eggs treated with neem oil at concentrations of 0.5%, 1%, or 2%. Transmission electron microscopy showed that two subtypes of endocrine cells, namely granular and vesicular, occurred in the midgut epithelium during the three stages of the life cycle. Both cell types did not reach the midgut lumen and were positioned basally in the epithelium. The endocrine cells did not show extensive infoldings of the basal plasma membrane, and there were numerous secretory granules in the basal region of the cytoplasm. In the granular endocrine cells, the granules were completely filled with a dense matrix. In the vesicular endocrine cells, the main secretory products consisted of haloed vesicles. Ultrastructural examination indicated that only the granular endocrine cells exhibited signs of morphologic changes of cell injury present in all life cycle stages after the larvae were chronically exposed to neem oil by ingestion. The major cellular damage consisted of dilatation and vesiculation of the rough endoplasmic reticulum and the development of smooth endoplasmic reticulum and mitochondrial swelling. Our data suggest that cytotoxic effects on midgut endocrine cells can contribute to a generalized disruption of the physiological processes in this organ due to a general alteration of endocrine function.

  12. Residues and persistence of neem formulations on strawberry after field treatment.

    PubMed

    Caboni, Pierluigi; Sarais, Giorgia; Angioni, Alberto; Garcia, Ana Juan; Lai, Francesco; Dedola, Fabrizio; Cabras, Paolo

    2006-12-27

    Azadirachtoids were determined by liquid chromatography/mass spectrometry (LC/MS) in five methanolic seed extracts of the neem tree and in a commercial formulation. On average, seed extracts contain azadirachtin A (10.9%), azadirachtin B (3.5%), nimbin (10.4%), and large quantities of salannin (19.0%). The composition of the commercial formulations may present different azadirachtoids contents depending on the natural extracts used in the preparation. Because these compounds may also show insecticide activity, the efficacy on field of these formulations may be very different. Photodegradation of pure azadirachtoids was also studied. Azadirachtins and related compounds are very sensitive to sunlight, degrading rapidly, with half-lives of the order of 11.3 h for azadirachtin A and 5.5 h for azadirachtin B and few minutes for the other limonoids compounds studied. The residues of azadirachtins and the main constituents, e.g., salannin, nimbin, deacetylnimbin, and deacetylsalannin, of the neem seed extract were determined on strawberries after field treatment using two different formulations. This residue study on strawberry was carried out to assess not only the azadirachtin content but also the main azadirachtoids contents. Three days after field application at five times the dose recommended by the manufacturer, residues of azadirachtin A and B were 0.03 and 0.01 mg/kg, respectively, while residues of salannin (LOQ 0.01 mg/kg) and nimbin (LOQ 0.5 mg/kg) were not detectable. PMID:17177537

  13. Efficacy and insecticidal properties of some essential oils against Caryedon serratus (Oliver)-a storage pest of groundnut.

    PubMed

    Harish, G; Nataraja, M V; Holajjer, Prasanna; Thirumalaisamy, P P; Jadon, K S; Savaliya, S D; Padavi, R D; Koradia, V G; Gedia, M V

    2014-11-01

    During storage groundnut is attacked by number of stored grain pest and management of these insect pests particularly bruchid beetle, Caryedon serratus (Oliver) is of prime importance as they directly damage the pod and kernels. Hence, some essential oils were tested for their insecticidal and fungicidal properties. Highest total bruchid mortality was recorded with the application of neem oil and pongamia oil at 10% (v/w) concentration and lowest in eucalyptus oil at 5% (v/w). Number of eggs laid was recorded 2.3 in neem oil 10% (v/w) which was lowest and significantly superior over untreated control and was at par with castor oil 10% (v/w) which recorded 2.5 eggs per 100 g of groundnut pods. There was no adult emergence in the groundnut pods treated with castor oil, eucalyptus oil, neem oil and pongamia oil at 10% (v/w) concentration. Groundnut pods treated with castor oil, eucalyptus oil, neem oil and pongamia oil at 10% (v/w) and neem oil at 5% (v/w) concentrations recorded no damage to pods and kernels and also zero per cent weight loss. These oils effectively influenced groundnut bruchid establishment and reduce damage besides reduction in aflatoxin contamination. PMID:26396354

  14. Anti dermatophytic activity of Azardirachta indica (neem) by invitro study.

    PubMed

    Natarajan, V; Pushkala, S; Karuppiah, V P; Prasad, P V S

    2002-07-01

    The leaf and seed extracts of the Plant Azardirachta indica were tested for antidermatophytic activity against dermatophytes such as Trichophyton ruberum, Trichophyton, Mentagrophytes, Trichophyton violaceum, Microsporum nanum and Epidermophyton floccosum by tube dilution technique. The minimum Inhibitory concentration (MIC) of neem seed extract was found to be lower tan that of neem leaf when tested against different species of Dermatophytes. PMID:12785173

  15. EFFICACY OF THAI NEEM OIL AGAINST AEDES AEGYPTI (L.) LARVAE.

    PubMed

    Silapanuntakul, Suthep; Keanjoom, Romnalin; Pandii, Wongdyan; Boonchuen, Supawadee; Sombatsiri, Kwanchai

    2016-05-01

    Trees with larvicidal activity may be found in Thailand. We conducted this study to evaluate the efficacy and length of efficacy of Thai neem (Azadirachta siamensis) oil emulsion and an alginate bead of Thai neem oil formulation against early fourth stage Aedes aegypti larvae using a dipping test. The Thai neem oil emulsion had significantly greater larvicidal activity than the alginate bead formulation at 12 to 60 hours post-exposure (p < 0.01). The Thai neem oil formulation resulted in 100% mortality among the early fourth stage Aedes aegypti larvae at 48 hours, while the alginate bead formulation resulted in 98% larval mortality at 84 hours and 100% mortality at 96 hours. The mean larval mortality using the Thai neem oil emulsion dropped to < 25% by 12 days and with the alginate beads dropped to < 25% by 15 days of exposure.

  16. EFFICACY OF THAI NEEM OIL AGAINST AEDES AEGYPTI (L.) LARVAE.

    PubMed

    Silapanuntakul, Suthep; Keanjoom, Romnalin; Pandii, Wongdyan; Boonchuen, Supawadee; Sombatsiri, Kwanchai

    2016-05-01

    Trees with larvicidal activity may be found in Thailand. We conducted this study to evaluate the efficacy and length of efficacy of Thai neem (Azadirachta siamensis) oil emulsion and an alginate bead of Thai neem oil formulation against early fourth stage Aedes aegypti larvae using a dipping test. The Thai neem oil emulsion had significantly greater larvicidal activity than the alginate bead formulation at 12 to 60 hours post-exposure (p < 0.01). The Thai neem oil formulation resulted in 100% mortality among the early fourth stage Aedes aegypti larvae at 48 hours, while the alginate bead formulation resulted in 98% larval mortality at 84 hours and 100% mortality at 96 hours. The mean larval mortality using the Thai neem oil emulsion dropped to < 25% by 12 days and with the alginate beads dropped to < 25% by 15 days of exposure. PMID:27405123

  17. Neem (Azadirachta indica): Prehistory to contemporary medicinal uses to humankind

    PubMed Central

    Kumar, Venugopalan Santhosh; Navaratnam, Visweswaran

    2013-01-01

    The divine tree neem (Azadirachta indica) is mainly cultivated in the Indian subcontinent. Neem has been used extensively by humankind to treat various ailments before the availability of written records which recorded the beginning of history. The world health organization estimates that 80% of the population living in the developing countries relies exclusively on traditional medicine for their primary health care. More than half of the world's population still relies entirely on plants for medicines, and plants supply the active ingredients of most traditional medical products. The review shows the neem has been used by humankind to treat various ailments from prehistory to contemporary. PMID:23835719

  18. NeeMDB: Convenient Database for Neem Secondary Metabolites

    PubMed Central

    Hatti, Kaushik S; Muralitharan, Lakshmi; Hegde, Rajendra; Kush, Anil

    2014-01-01

    Indian Neem tree is known for its pesticidal and medicinal properties for centuries. Structure elucidation of large number of secondary metabolites responsible for its diverse properties has been achieved. However, this data is spread over various books, scientific reports and publications and difficult to access. We have compiled and stored structural details of neem metabolites in NeeMDB, a database which can be easily accessed, queried and downloaded. NeeMDB would be central in dissipating structural information of neem secondary metabolites world over. PMID:24966540

  19. Neem (Azadirachta indica): prehistory to contemporary medicinal uses to humankind.

    PubMed

    Kumar, Venugopalan Santhosh; Navaratnam, Visweswaran

    2013-07-01

    The divine tree neem (Azadirachta indica) is mainly cultivated in the Indian subcontinent. Neem has been used extensively by humankind to treat various ailments before the availability of written records which recorded the beginning of history. The world health organization estimates that 80% of the population living in the developing countries relies exclusively on traditional medicine for their primary health care. More than half of the world's population still relies entirely on plants for medicines, and plants supply the active ingredients of most traditional medical products. The review shows the neem has been used by humankind to treat various ailments from prehistory to contemporary.

  20. Effect of Dursban 480 EC (chlorpyrifos) and Talstar 10 EC (bifenthrin) on the physiological and genetic diversity of microorganisms in soil.

    PubMed

    Medo, Juraj; Maková, Jana; Kovácsová, Silvia; Majerčíková, Kamila; Javoreková, Soňa

    2015-01-01

    This investigation was undertaken to determine the impact of the insecticides Dursban 480 EC (with organophosphate compound chlorpyrifos as the active ingredient) and Talstar 10 EC (with pyrethroid bifenthrin as the active ingredient) on the respiration activity and microbial diversity in a sandy loam luvisol soil. The insecticides were applied in two doses: the maximum recommended dose for field application (15 mg kg(-1) for Dursban 480 EC and 6 mg kg(-1) for Talstar 10 EC) and a 100-fold higher dose for extrapolation of their effect. Bacterial and fungal genetic diversity was analysed in soil samples using PCR DGGE and the functional diversity (catabolic potential) was studied using BIOLOG EcoPlates at 1, 3, 7, 14, 28, 56 and 112 days after insecticide application. Five bacterial groups (α, β, γ proteobacteria, firmibacteria and actinomycetes) and five groups of fungi or fungus-like microorganisms (Ascomycota, Basidiomycota, Chytridiomycota, Oomycota and Zygomycota) were analysed using specific primer sets. This approach provides high resolution of the analysis covering majority of microorganisms in the soil. Only the high-dose Dursban 480 EC significantly changed the community of microorganisms. We observed its negative effect on α- and γ-proteobacteria, as the number of OTUs (operational taxonomic units) decreased until the end of incubation. In the β-proteobacteria group, initial increase of OTUs was followed by strong decrease. Diversity in the firmibacteria, actinomycetes and Zygomycota groups was minimally disturbed by the insecticide application. Dursban 480 EC, however, both positively and negatively affected certain species. Among negatively affected species Sphingomonas, Flavobacterium or Penicillium were detected, but Achromobacter, Luteibacter or Aspergillus were supported by applied insecticide. The analysis of BIOLOG plates using AWCD values indicated a significant increase in metabolic potential of microorganisms in the soil after the high

  1. Effect of Dursban 480 EC (chlorpyrifos) and Talstar 10 EC (bifenthrin) on the physiological and genetic diversity of microorganisms in soil.

    PubMed

    Medo, Juraj; Maková, Jana; Kovácsová, Silvia; Majerčíková, Kamila; Javoreková, Soňa

    2015-01-01

    This investigation was undertaken to determine the impact of the insecticides Dursban 480 EC (with organophosphate compound chlorpyrifos as the active ingredient) and Talstar 10 EC (with pyrethroid bifenthrin as the active ingredient) on the respiration activity and microbial diversity in a sandy loam luvisol soil. The insecticides were applied in two doses: the maximum recommended dose for field application (15 mg kg(-1) for Dursban 480 EC and 6 mg kg(-1) for Talstar 10 EC) and a 100-fold higher dose for extrapolation of their effect. Bacterial and fungal genetic diversity was analysed in soil samples using PCR DGGE and the functional diversity (catabolic potential) was studied using BIOLOG EcoPlates at 1, 3, 7, 14, 28, 56 and 112 days after insecticide application. Five bacterial groups (α, β, γ proteobacteria, firmibacteria and actinomycetes) and five groups of fungi or fungus-like microorganisms (Ascomycota, Basidiomycota, Chytridiomycota, Oomycota and Zygomycota) were analysed using specific primer sets. This approach provides high resolution of the analysis covering majority of microorganisms in the soil. Only the high-dose Dursban 480 EC significantly changed the community of microorganisms. We observed its negative effect on α- and γ-proteobacteria, as the number of OTUs (operational taxonomic units) decreased until the end of incubation. In the β-proteobacteria group, initial increase of OTUs was followed by strong decrease. Diversity in the firmibacteria, actinomycetes and Zygomycota groups was minimally disturbed by the insecticide application. Dursban 480 EC, however, both positively and negatively affected certain species. Among negatively affected species Sphingomonas, Flavobacterium or Penicillium were detected, but Achromobacter, Luteibacter or Aspergillus were supported by applied insecticide. The analysis of BIOLOG plates using AWCD values indicated a significant increase in metabolic potential of microorganisms in the soil after the high

  2. Metals Bioaccumulation Mechanism in Neem Bark.

    PubMed

    Krishnani, Kishore K; Boddu, Veera M; Moon, Deok Hyun; Ghadge, S V; Sarkar, Biplab; Brahmane, M P; Choudhary, K; Kathiravan, V; Meng, Xiaoguang

    2015-09-01

    The aim of this work was to define the bioaccumulation mechanism of metals onto the non-living biomaterial prepared from an extensively available plant bark biomass of neem (Azadirachta indica). Based on maximum ultimate fixation capacities (mmol/g) of the product, metals ions could be arranged as Hg(2+) < Cd(2+) < Pb(2+) ≅ Cu(2+). Surface properties of the biomaterial were characterized by X-ray photoelectron spectroscopy and X-ray diffraction techniques for their sorption mechanism. Whewellite (C2CaO4 · H2O) was identified in the biomaterial, which indicated that calcium ions are electrovalently bonded with carboxylate ions facilitating the ion exchange mechanism with metal ions. Bioaccumulation of metal ions was also studied by Fourier transform infrared spectroscopy, which indicated the presence of functional groups implicated in adsorbing metal ions. Biomaterial did not adsorb anionic As(III), As(V) and Cr(VI), because of their electrostatic repulsion with carboxylic functional groups. Neem bark can be used as bioindicators, bioaccumulators and biomonitors while determining environmental pressures. Metal bioaccumulative properties and structural investigation of plant bark has potential in providing quantitative information on the metal contamination in the surrounding environment. PMID:26193837

  3. Metals Bioaccumulation Mechanism in Neem Bark.

    PubMed

    Krishnani, Kishore K; Boddu, Veera M; Moon, Deok Hyun; Ghadge, S V; Sarkar, Biplab; Brahmane, M P; Choudhary, K; Kathiravan, V; Meng, Xiaoguang

    2015-09-01

    The aim of this work was to define the bioaccumulation mechanism of metals onto the non-living biomaterial prepared from an extensively available plant bark biomass of neem (Azadirachta indica). Based on maximum ultimate fixation capacities (mmol/g) of the product, metals ions could be arranged as Hg(2+) < Cd(2+) < Pb(2+) ≅ Cu(2+). Surface properties of the biomaterial were characterized by X-ray photoelectron spectroscopy and X-ray diffraction techniques for their sorption mechanism. Whewellite (C2CaO4 · H2O) was identified in the biomaterial, which indicated that calcium ions are electrovalently bonded with carboxylate ions facilitating the ion exchange mechanism with metal ions. Bioaccumulation of metal ions was also studied by Fourier transform infrared spectroscopy, which indicated the presence of functional groups implicated in adsorbing metal ions. Biomaterial did not adsorb anionic As(III), As(V) and Cr(VI), because of their electrostatic repulsion with carboxylic functional groups. Neem bark can be used as bioindicators, bioaccumulators and biomonitors while determining environmental pressures. Metal bioaccumulative properties and structural investigation of plant bark has potential in providing quantitative information on the metal contamination in the surrounding environment.

  4. Selective effects of natural and synthetic insecticides on mortality of Spodoptera frugiperda (Lepidoptera: Noctuidae) and its predator Eriopis connexa (Coleoptera: Coccinellidae).

    PubMed

    Tavares, Wagner S; Costa, Mariana A; Cruz, Ivan; Silveira, Rodrigo D; Serrao, Jose E; Zanuncio, Jose C

    2010-08-01

    Spodoptera frugiperda Smith (Lepidoptera: Noctuidae) is a serious pest of corn in several American countries. It is mainly controlled with synthetic insecticides. The objectives of this study were to evaluate the effects of the natural products, neem oil and pyroligneous extract, and the synthetic insecticide, lufenuron, at 2.50 mL water (0.25%) on the mortality of 2-, 4- and 6-day-old caterpillars of S. frugiperda, and their selectivities against fourth instar larvae of Eriopis connnexa Germar (Coleoptera: Coccinellidae). Four- and 6-day-old S. frugiperda caterpillars showed higher mortality after exposure to neem oil (83.33 +/- 0.83 and 89.58 +/- 0.90%, respectively) and lufenuron (95.83 +/- 0.96 and 85.41 +/- 0.83%), compared to pyroligneous extract (68.75 +/- 0.69 and 31.25 +/- 0.31%). The deleterious effect of pyroligneous extract was higher in 2- (83.33 +/- 0.83% mortality) and 4-day-old (68.75 +/- 0.69%) S. frugiperda caterpillars than in 6-day-old caterpillars (31.25 +/- 0.31%). Larval mortality of the predator E. connexa was lower with neem oil and pyroligneous extract (25.00 +/- 0.33%) than with lufenuron (91.66 +/- 1.22%). Neem oil is thus recommended for control of S. frugiperda because of its high toxicity, combined with its relatively low toxicity to larvae of the natural enemy E. connexa. PMID:20603748

  5. Deterrent effects of four neem-based formulations on gravid female boll weevil (Coleoptera: Curculionidae) feeding and oviposition on cotton squares.

    PubMed

    Showler, A T; Greenberg, S M; Arnason, J T

    2004-04-01

    Three commercial neem-based insecticides, Agroneem, Ecozin, and Neemix, and a neem seed extract formulation, bitters, containing 1,036, 16,506, 471, and 223 microg/ml azadirachtin, respectively, were assessed for feeding and oviposition deterrence against gravid female boll weevils, Anthonomus grandis grandis Boheman, in the laboratory. In choice assays, excised cotton squares dipped in the separate formulations were first physically contacted by the weevils' tarsi or antennae fewer times than nontreated control squares. In choice and no-choice assays, each formulation repelled the weevils for > or = 90 min. After 24 h in the choice assays, feeding punctures on the squares treated with Agroneem, Ecozin, or bitters were significantly fewer compared with controls. Egg punctures on the Ecozin- and the bitters-treated squares were significantly fewer than on control squares after 24 h. In the no-choice assay, no significant difference was detected. Aging the formulations under outdoor conditions for 24 h before weevils were exposed resulted in 46-60% and 62-82% reductions in feeding and oviposition punctures, respectively, compared with controls. Agroneem- and bitters-treated squares had > 37% fewer feeding punctures after being aged for 48 h. No significant difference was detected after 72 h of aging. Because the deterrence of the gravid female boll weevils was not correlated with amounts of azadirachtin, azadirachtin does not seem to be the only, or the most influential, component of neem that induced the observed deterrence. PMID:15154463

  6. Neem oil poisoning: Case report of an adult with toxic encephalopathy.

    PubMed

    Mishra, Ajay; Dave, Nikhil

    2013-09-01

    Neem oil has widespread use in Indian subcontinent due to its many bioactive properties. Azadirachtin, an active ingredient, is implicated in causing the effects seen in neem oil poisoning. Neem oil poisoning is rare in adults. This report highlights the toxicity associated with neem oil poisoning in an elderly male. The patient presented with vomiting, seizures, metabolic acidosis, and toxic encephalopathy. The patient recovered completely with symptomatic treatment. PMID:24339648

  7. Neem oil poisoning: Case report of an adult with toxic encephalopathy.

    PubMed

    Mishra, Ajay; Dave, Nikhil

    2013-09-01

    Neem oil has widespread use in Indian subcontinent due to its many bioactive properties. Azadirachtin, an active ingredient, is implicated in causing the effects seen in neem oil poisoning. Neem oil poisoning is rare in adults. This report highlights the toxicity associated with neem oil poisoning in an elderly male. The patient presented with vomiting, seizures, metabolic acidosis, and toxic encephalopathy. The patient recovered completely with symptomatic treatment.

  8. 40 CFR 180.1291 - Cold pressed neem oil; exemption from the requirement of a tolerance.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Cold pressed neem oil; exemption from... FOOD Exemptions From Tolerances § 180.1291 Cold pressed neem oil; exemption from the requirement of a tolerance. Residues of the biochemical pesticide cold pressed neem oil are exempt from the requirement of...

  9. Coating of Prilled Urea with Neem (Azadirachta Indica Juss) Oil for Efficient Nitrogen Use in Rice

    NASA Astrophysics Data System (ADS)

    Prasad, R.; Singh, S.; Saxena, V. S.; Devkumar, C.

    A field study made with rice at the Indian Agricultural Research Institute, New Delhi, showed that coating urea with neem oil, neem cake or neem oil microemulsion improved rice growth and resulted in more grain and straw than did commercial prilled urea.

  10. 40 CFR 180.1291 - Cold pressed neem oil; exemption from the requirement of a tolerance.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 24 2011-07-01 2011-07-01 false Cold pressed neem oil; exemption from... FOOD Exemptions From Tolerances § 180.1291 Cold pressed neem oil; exemption from the requirement of a tolerance. Residues of the biochemical pesticide cold pressed neem oil are exempt from the requirement of...

  11. 40 CFR 180.1291 - Cold pressed neem oil; exemption from the requirement of a tolerance.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 25 2013-07-01 2013-07-01 false Cold pressed neem oil; exemption from... FOOD Exemptions From Tolerances § 180.1291 Cold pressed neem oil; exemption from the requirement of a tolerance. Residues of the biochemical pesticide cold pressed neem oil are exempt from the requirement of...

  12. 40 CFR 180.1291 - Cold pressed neem oil; exemption from the requirement of a tolerance.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 24 2014-07-01 2014-07-01 false Cold pressed neem oil; exemption from... FOOD Exemptions From Tolerances § 180.1291 Cold pressed neem oil; exemption from the requirement of a tolerance. Residues of the biochemical pesticide cold pressed neem oil are exempt from the requirement of...

  13. 40 CFR 180.1291 - Cold pressed neem oil; exemption from the requirement of a tolerance.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 25 2012-07-01 2012-07-01 false Cold pressed neem oil; exemption from... FOOD Exemptions From Tolerances § 180.1291 Cold pressed neem oil; exemption from the requirement of a tolerance. Residues of the biochemical pesticide cold pressed neem oil are exempt from the requirement of...

  14. Proteases as Insecticidal Agents

    PubMed Central

    Harrison, Robert L.; Bonning, Bryony C.

    2010-01-01

    Proteases from a variety of sources (viruses, bacteria, fungi, plants, and insects) have toxicity towards insects. Some of these insecticidal proteases evolved as venom components, herbivore resistance factors, or microbial pathogenicity factors, while other proteases play roles in insect development or digestion, but exert an insecticidal effect when over-expressed from genetically engineered plants or microbial pathogens. Many of these proteases are cysteine proteases, although insect-toxic metalloproteases and serine proteases have also been examined. The sites of protease toxic activity range from the insect midgut to the hemocoel (body cavity) to the cuticle. This review discusses these insecticidal proteases along with their evaluation and use as potential pesticides. PMID:22069618

  15. Shedding light on bioactivity of botanical by-products: neem cake compounds deter oviposition of the arbovirus vector Aedes albopictus (Diptera: Culicidae) in the field.

    PubMed

    Benelli, Giovanni; Conti, Barbara; Garreffa, Rita; Nicoletti, Marcello

    2014-03-01

    Industrial plant-borne by-products can be sources of low-cost chemicals, potentially useful to build eco-friendly control strategies against mosquitoes. Neem cake is a cheap by-product of neem oil extraction obtained by pressing the seeds of Azadirachta indica. Neem products are widely used as insecticides since rarely induce resistance because their multiple mode of action against insect pests and low-toxicity rates have been detected against vertebrates. In this research, we used field bioassays to assess the effective oviposition repellence of neem cake fractions of increasing polarity [n-hexane (A), methanol (B), ethyl acetate (C), n-butanol (D), and aqueous (E) fraction] against Aedes albopictus, currently the most invasive mosquito worldwide. These fractions, already characterized for low nortriterpenoids contents by HPLC analyses, were analyzed for their total content by HPTLC, highlighting striking differences in their chemical composition. Field results showed that B, A, and C tested at 100 ppm exerted higher effective repellence over the control (71.33, 88.59, and 73.49% of ER, respectively), while E and D did not significantly deter A. albopictus oviposition (17.06 and 22.72% of ER, respectively). The highest oviposition activity index was achieved by A (-0.82), followed by C (-0.63), and B (-0.62). Lower OAIs were achieved by D (-0.14) and E (-0.09). On the basis of our results, we believe that A, B, and C are very promising as oviposition deterrents against the arbovirus vector A. albopictus since they are proved as rich in active metabolites, cheap, and really effective at low doses.

  16. Side Effects of Neem Oil on the Midgut Endocrine Cells of the Green Lacewing Ceraeochrysa claveri (Navás) (Neuroptera: Chrysopidae).

    PubMed

    Scudeler, E L; Santos, D C

    2014-04-01

    We described the ultrastructure of Ceraeochrysa claveri (Navás) midgut endocrine cells in larva, pupa, and adult, and evaluated the side effects of ingested neem oil, a botanical insecticide obtained from the seeds of the neem tree (Azadirachta indica), on these cells. During the larval period, C. claveri were fed (ad libitum) Diatraea saccharalis (F.) eggs treated with neem oil at concentrations of 0.5%, 1%, or 2%. Transmission electron microscopy showed that two subtypes of endocrine cells, namely granular and vesicular, occurred in the midgut epithelium during the three stages of the life cycle. Both cell types did not reach the midgut lumen and were positioned basally in the epithelium. The endocrine cells did not show extensive infoldings of the basal plasma membrane, and there were numerous secretory granules in the basal region of the cytoplasm. In the granular endocrine cells, the granules were completely filled with a dense matrix. In the vesicular endocrine cells, the main secretory products consisted of haloed vesicles. Ultrastructural examination indicated that only the granular endocrine cells exhibited signs of morphologic changes of cell injury present in all life cycle stages after the larvae were chronically exposed to neem oil by ingestion. The major cellular damage consisted of dilatation and vesiculation of the rough endoplasmic reticulum and the development of smooth endoplasmic reticulum and mitochondrial swelling. Our data suggest that cytotoxic effects on midgut endocrine cells can contribute to a generalized disruption of the physiological processes in this organ due to a general alteration of endocrine function. PMID:27193522

  17. Shedding light on bioactivity of botanical by-products: neem cake compounds deter oviposition of the arbovirus vector Aedes albopictus (Diptera: Culicidae) in the field.

    PubMed

    Benelli, Giovanni; Conti, Barbara; Garreffa, Rita; Nicoletti, Marcello

    2014-03-01

    Industrial plant-borne by-products can be sources of low-cost chemicals, potentially useful to build eco-friendly control strategies against mosquitoes. Neem cake is a cheap by-product of neem oil extraction obtained by pressing the seeds of Azadirachta indica. Neem products are widely used as insecticides since rarely induce resistance because their multiple mode of action against insect pests and low-toxicity rates have been detected against vertebrates. In this research, we used field bioassays to assess the effective oviposition repellence of neem cake fractions of increasing polarity [n-hexane (A), methanol (B), ethyl acetate (C), n-butanol (D), and aqueous (E) fraction] against Aedes albopictus, currently the most invasive mosquito worldwide. These fractions, already characterized for low nortriterpenoids contents by HPLC analyses, were analyzed for their total content by HPTLC, highlighting striking differences in their chemical composition. Field results showed that B, A, and C tested at 100 ppm exerted higher effective repellence over the control (71.33, 88.59, and 73.49% of ER, respectively), while E and D did not significantly deter A. albopictus oviposition (17.06 and 22.72% of ER, respectively). The highest oviposition activity index was achieved by A (-0.82), followed by C (-0.63), and B (-0.62). Lower OAIs were achieved by D (-0.14) and E (-0.09). On the basis of our results, we believe that A, B, and C are very promising as oviposition deterrents against the arbovirus vector A. albopictus since they are proved as rich in active metabolites, cheap, and really effective at low doses. PMID:24337544

  18. Naturally occurring insecticides.

    PubMed Central

    Soloway, S B

    1976-01-01

    Naturally occurring insecticides are abundant and varied in their effects, though but a few are articles of commerce. Even for these, pyrethrum, nicotine, rotenone, hellebore, ryania, and sabadilla, there is a paucity of information on mammalian toxicology and environmental effects. In general, these materials are characterized favorably by low acute toxicity and ready dissipation in nature. Unfavorable aspects of natural insecticides are the contained mixture of active and inactive components and the low active ingredient content on a crop yield basis pointing to a high unit cost. Natural insecticides can serve additionally as leads to unnatural mimics, of which the commercially successful synthetic pyrethroids are prime examples. The chemical nature, relationship of insecticidal activity to chemical structure, occurrence, production, and utilization, registered uses, metabolism, and insect and mammalian toxicity are reviewed. PMID:789058

  19. Insecticides and Biological Control

    ERIC Educational Resources Information Center

    Furness, G. O.

    1972-01-01

    Use of insecticides has been questioned due to their harmful effects on edible items. Biological control of insects along with other effective practices for checking spread of parasites on crops are discussed. (PS)

  20. Insecticide Compendium. MP-29.

    ERIC Educational Resources Information Center

    Spackman, Everett W.; And Others

    This document presents information on most of the known insecticides and their general usage, toxicity, formulation, compound type, manufacturers, and the chemical, trade and common names applied to each compound. (CS)

  1. Design, synthesis and insecticidal evaluation of aryloxy dihalopropene derivatives.

    PubMed

    Yang, Ji-Chun; Li, Miao; Wu, Qiao; Liu, Chang-Ling; Chang, Xiu-Hui

    2016-02-01

    Plutella xylostella (P. xylostella) is a highly migratory, cosmopolitan species and one of the most important pest of cruciferous crops worldwide. Pyridalyl as a novel class of insecticides has good efficacy against P. xylostella. On the basis of the commercial insecticide pyridalyl, a series of new aryloxy dihalopropene derivatives were designed and synthesized by using Intermediate Derivatization Methods. Their chemical structures were confirmed by (1)H NMR, high-resolution mass spectrum (HRMS), and single-crystal X-ray diffraction analysis. The insecticidal activities of the new compounds against P. xylostella were evaluated. The results of bioassays indicated that most of the compounds showed moderate to high activities at the tested concentration, especially compounds 10e and 10g displayed more than 75% insecticidal activity against P. xylostella at 6.25mg/L, while pyridalyl showed 50% insecticidal activity at the same concentration. The field trials result of the insecticidal activities showed that compound 10e as a 10% emulsifiable concentrate (EC) was effective in the control of P. xylostella at 75-150g a.i./ha, and the mortality of P. xylostella for treatment with compound 10e at 75g a.i./ha was equivalent to pyridalyl at 105g a.i./ha. PMID:26432606

  2. Biodegradable polymer based encapsulation of neem oil nanoemulsion for controlled release of Aza-A.

    PubMed

    Jerobin, Jayakumar; Sureshkumar, R S; Anjali, C H; Mukherjee, Amitava; Chandrasekaran, Natarajan

    2012-11-01

    Azadirachtin a biological compound found in neem have medicinal and pesticidal properties. The present work reports on the encapsulation of neem oil nanoemulsion using sodium alginate (Na-Alg) by cross linking with glutaraldehyde. Starch and polyethylene glycol (PEG) were used as coating agents for smooth surface of beads. The SEM images showed beads exhibited nearly spherical shape. Swelling of the polymeric beads reduced with coating which in turn decreased the rate of release of Aza-A. Starch coated encapsulation of neem oil nanoemulsion was found to be effective when compared to PEG coated encapsulation of neem oil nanoemulsion. The release rate of neem Aza-A from the beads into an aqueous environment was analyzed by UV-visible spectrophotometer (214 nm). The encapsulated neem oil nanoemulsion have the potential for controlled release of Aza-A. Neem oil nanoemulsion encapsulated beads coated with PEG was found to be toxic in lymphocyte cells.

  3. Biodegradable polymer based encapsulation of neem oil nanoemulsion for controlled release of Aza-A.

    PubMed

    Jerobin, Jayakumar; Sureshkumar, R S; Anjali, C H; Mukherjee, Amitava; Chandrasekaran, Natarajan

    2012-11-01

    Azadirachtin a biological compound found in neem have medicinal and pesticidal properties. The present work reports on the encapsulation of neem oil nanoemulsion using sodium alginate (Na-Alg) by cross linking with glutaraldehyde. Starch and polyethylene glycol (PEG) were used as coating agents for smooth surface of beads. The SEM images showed beads exhibited nearly spherical shape. Swelling of the polymeric beads reduced with coating which in turn decreased the rate of release of Aza-A. Starch coated encapsulation of neem oil nanoemulsion was found to be effective when compared to PEG coated encapsulation of neem oil nanoemulsion. The release rate of neem Aza-A from the beads into an aqueous environment was analyzed by UV-visible spectrophotometer (214 nm). The encapsulated neem oil nanoemulsion have the potential for controlled release of Aza-A. Neem oil nanoemulsion encapsulated beads coated with PEG was found to be toxic in lymphocyte cells. PMID:22944443

  4. Organophosphorus Insecticide Pharmacokinetics

    SciTech Connect

    Timchalk, Charles

    2010-01-01

    This chapter highlights a number of current and future applications of pharmacokinetics to assess organophosphate (OP) insecticide dosimetry, biological response and risk in humans exposed to these agents. Organophosphates represent a large family of pesticides where insecticidal as well as toxicological mode of action is associated with their ability to target and inhibit acetylcholinesterase (AChE). Pharmacokinetics entails the quantitative integration of physiological and metabolic processes associated with the absorption, distribution, metabolism and excretion (ADME) of drugs and xenobiotics. Pharmacokinetic studies provide important data on the amount of toxicant delivered to a target site as well as species-, age-, gender-specific and dose-dependent differences in biological response. These studies have been conducted with organophosphorus insecticides in multiple species, at various dose levels, and across different routes of exposure to understand their in vivo pharmacokinetics and how they contribute to the observed toxicological response. To access human exposure to organophosphorus insecticides, human pharmacokinetic studies have been conducted and used to develop biological monitoring strategies based on the quantitation of key metabolites in biological fluids. Pharmacokinetic studies with these insecticides are also useful to facilitate extrapolation of dosimetry and biological response from animals to humans and for the assessment of human health risk. In this regard, physiologically based pharmacokinetic and pharmacodynamic (PBPK/PD) models are being utilized to assess risk and understand the toxicological implications of known or suspected exposures to various insecticides. In this chapter a number of examples are presented that illustrate the utility and limitation of pharmacokinetic studies to address human health concerns associated with organophosphorus insecticides.

  5. A comparative study of insecticide toxicity among seven cladoceran species.

    PubMed

    Mano, Hiroyuki; Sakamoto, Masaki; Tanaka, Yoshinari

    2010-11-01

    The sensitivities of seven cladoceran species (Ceriodaphnia reticulata, Chydorus sphaericus, Daphnia galeata, Diaphanosoma brachyurum, Moina macrocopa, Scapholeberis kingi, and Simocephalus vetulus) to carbamate insecticides (carbaryl and methomyl) were investigated by acute toxicity tests. The sensitivities to carbaryl and methomyl were highly correlated among the tested organisms, but the co-tolerance level varied markedly among species. C. reticulata showed the highest sensitivity, whereas M. macrocopa and S. kingi showed the lowest sensitivities to the two insecticides. These results indicate that the degree of chemical impacts on natural communities can vary depending on cladoceran species composition. The highly positive correlation between the EC(50) values for both insecticides indicates that the two chemicals have a shared mode of action on cladoceran species. Unlike previous reports, acute toxicity was not correlated with body size. The results are discussed in relation to community-level experiments, the functions of freshwater ecosystems, and ecological risk assessment. PMID:20862541

  6. Effect of neem leaf extract and neem oil on Penicillium growth, sporulation, morphology and ochratoxin A production.

    PubMed

    Mossini, Simone A G; Arrotéia, Carla C; Kemmelmeier, Carlos

    2009-09-01

    In vitro trials were conducted to evaluate the effect of Azadirachtaindica (neem) extracts on mycelial growth, sporulation, morphology and ochratoxin A production by P. verrucosum and P. brevicompactum. The effect of neem oil extract from seeds and leaf was evaluated at 0.125; 0.25 and 0.5% and 6.25 and 12.5 mg/mL, respectively, in Yeast Extract Sucrose (YES) medium. Ochratoxin A production was evaluated by a thin-layer chromatography technique. Oil extracts exhibited significant (p ≤ 0.05) reduction of growth and sporulation of the fungi. No inhibition of ochratoxin A production was observed. Given its accessibility and low cost, neem oil could be implemented as part of a sustainable integrated pest management strategy for plant disease, as it has been shown to be fungitoxic by inhibition of growth and sporulation. PMID:22069528

  7. Insecticide Resistance in Fleas

    PubMed Central

    Rust, Michael K.

    2016-01-01

    Fleas are the major ectoparasite of cats, dogs, and rodents worldwide and potential vectors of animal diseases. In the past two decades the majority of new control treatments have been either topically applied or orally administered to the host. Most reports concerning the development of insecticide resistance deal with the cat flea, Ctenocephalides felis felis. Historically, insecticide resistance has developed to many of the insecticides used to control fleas in the environment including carbamates, organophosphates, and pyrethroids. Product failures have been reported with some of the new topical treatments, but actual resistance has not yet been demonstrated. Failures have often been attributed to operational factors such as failure to adequately treat the pet and follow label directions. With the addition of so many new chemistries additional monitoring of flea populations is needed. PMID:26999217

  8. Insecticide Resistance in Fleas.

    PubMed

    Rust, Michael K

    2016-03-17

    Fleas are the major ectoparasite of cats, dogs, and rodents worldwide and potential vectors of animal diseases. In the past two decades the majority of new control treatments have been either topically applied or orally administered to the host. Most reports concerning the development of insecticide resistance deal with the cat flea, Ctenocephalides felis felis. Historically, insecticide resistance has developed to many of the insecticides used to control fleas in the environment including carbamates, organophosphates, and pyrethroids. Product failures have been reported with some of the new topical treatments, but actual resistance has not yet been demonstrated. Failures have often been attributed to operational factors such as failure to adequately treat the pet and follow label directions. With the addition of so many new chemistries additional monitoring of flea populations is needed.

  9. Insecticide Resistance in Fleas.

    PubMed

    Rust, Michael K

    2016-01-01

    Fleas are the major ectoparasite of cats, dogs, and rodents worldwide and potential vectors of animal diseases. In the past two decades the majority of new control treatments have been either topically applied or orally administered to the host. Most reports concerning the development of insecticide resistance deal with the cat flea, Ctenocephalides felis felis. Historically, insecticide resistance has developed to many of the insecticides used to control fleas in the environment including carbamates, organophosphates, and pyrethroids. Product failures have been reported with some of the new topical treatments, but actual resistance has not yet been demonstrated. Failures have often been attributed to operational factors such as failure to adequately treat the pet and follow label directions. With the addition of so many new chemistries additional monitoring of flea populations is needed. PMID:26999217

  10. Botanicals, selective insecticides, and predators to control Diaphorina citri (Hemiptera: Liviidae) in citrus orchards.

    PubMed

    Khan, Azhar A; Afzal, Muhammad; Qureshi, Jawwad A; Khan, Arif M; Raza, Abubakar M

    2014-12-01

    The Asian citrus psyllid (ACP) Diaphorina citri Kuwayama vectors pathogens that cause huanglongbing (HLB) or citrus greening devastating and economically important disease present in most citrus growing regions. Young citrus shoots are required for psyllid reproduction and development. During winter citrus trees produce little or no new growth. Overwintering adults reproduce in spring on newly emerging shoots also attractive to other pests and beneficial insects. Botanicals and relatively selective insecticides could help to conserve beneficial insects and reduce pest resistance to insecticides. Sprays of Azadirachtin (Neem), Tropane (Datura), Spirotetramat, Spinetoram, and broad-spectrum Imidacloprid were evaluated to control ACP in spring and summer on 10-year-old "Kinow" Citrus reticulata Blanco trees producing new growth. Psyllid populations were high averaging 5-9 nymphs or adults per sample before treatment application. Nymphs or adults were significantly reduced to 0.5-1.5 per sample in all treatments for 3 weeks, average 61%-83% reduction. No significant reduction in ladybeetles Adalia bipunctata, Aneglei scardoni, Cheilomenes sexmaculata, and Coccinella septempunctata was observed. Syrphids, spiders and green lacewings were reduced in treated trees except with Tropane. Studies are warranted to assess impact of these predators on ACP and interaction with insecticides. Observed reduction in ACP populations may not be enough considering its reproductive potential and role in the spread of HLB. Follow-up sprays may be required to achieve additional suppression using rotations of different insecticides. PMID:25205398

  11. Botanicals, selective insecticides, and predators to control Diaphorina citri (Hemiptera: Liviidae) in citrus orchards.

    PubMed

    Khan, Azhar A; Afzal, Muhammad; Qureshi, Jawwad A; Khan, Arif M; Raza, Abubakar M

    2014-12-01

    The Asian citrus psyllid (ACP) Diaphorina citri Kuwayama vectors pathogens that cause huanglongbing (HLB) or citrus greening devastating and economically important disease present in most citrus growing regions. Young citrus shoots are required for psyllid reproduction and development. During winter citrus trees produce little or no new growth. Overwintering adults reproduce in spring on newly emerging shoots also attractive to other pests and beneficial insects. Botanicals and relatively selective insecticides could help to conserve beneficial insects and reduce pest resistance to insecticides. Sprays of Azadirachtin (Neem), Tropane (Datura), Spirotetramat, Spinetoram, and broad-spectrum Imidacloprid were evaluated to control ACP in spring and summer on 10-year-old "Kinow" Citrus reticulata Blanco trees producing new growth. Psyllid populations were high averaging 5-9 nymphs or adults per sample before treatment application. Nymphs or adults were significantly reduced to 0.5-1.5 per sample in all treatments for 3 weeks, average 61%-83% reduction. No significant reduction in ladybeetles Adalia bipunctata, Aneglei scardoni, Cheilomenes sexmaculata, and Coccinella septempunctata was observed. Syrphids, spiders and green lacewings were reduced in treated trees except with Tropane. Studies are warranted to assess impact of these predators on ACP and interaction with insecticides. Observed reduction in ACP populations may not be enough considering its reproductive potential and role in the spread of HLB. Follow-up sprays may be required to achieve additional suppression using rotations of different insecticides.

  12. Use of neem cake as an organic substrate component

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Nursery and greenhouse growers continue to seek materials to decrease costs of plant production while maintaining environmental stewardship. Incorporation of neem cake as a substrate component could potentially impact nitrogen release as a result of altering substrate bacterial activity. The study...

  13. Haemolytic anaemia after ingestion of Neem (Azadirachta indica) tea

    PubMed Central

    Page, Cristy; Hawes, Emily M

    2013-01-01

    The authors report a clinically relevant and possible cause of haemolytic anaemia from ingestion of a Mexican tea from the Neem tree, also known as Azadirachta indica, in a 35-year-old Hispanic man who was found to have glucose-6-phosphate dehydrogenase deficiency. PMID:24136910

  14. ANTICHOLINESTERASE INSECTICIDE RETROSPECTIVE

    PubMed Central

    Casida, John E.; Durkin, Kathleen A.

    2012-01-01

    The anticholinesterase (antiChE) organophosphorus (OP) and methylcarbamate (MC) insecticides have been used very effectively as contact and systemic plant protectants for seven decades. About 90 of these compounds are still in use – the largest number for any insecticide chemotype or mode of action. In both insects and mammals, AChE inhibition and acetylcholine accumulation leads to excitation and death. The cholinergic system of insects is located centrally (where it is protected from ionized OPs and MCs) but not at the neuromuscular junction. Structural differences between insect and mammalian AChE are also evident in their genomics, amino acid sequences and active site conformations. Species selectivity is determined in part by inhibitor and target site specificity. Pest population selection with OPs and MCs has resulted in a multitude of modified AChEs of altered inhibitor specificity some conferring insecticide resistance and others enhancing sensitivity. Much of the success of antiChE insecticides results from a suitable balance of bioactivation and detoxification by families of CYP450 oxidases, hydrolases, glutathione S-transferases and others. Known inhibitors for these enzymes block detoxification and enhance potency which is particularly important in resistant strains. The current market for OPs and MCs of 19% of worldwide insecticide sales is only half of that of 10 years ago for several reasons: there have been no major new compounds for 30 years; resistance has eroded their effectiveness; human toxicity problems are still encountered; the patents have expired reducing the incentive to update registration packages; alternative chemotypes or control methods have been developed. Despite this decline, they still play a major role in pest control and the increasing knowledge on their target sites and metabolism may make it possible to redesign the inhibitors for insensitive AChEs and to target new sites in the cholinergic system. The OPs and MCs are down

  15. Neem Limonoids as Anticancer Agents: Modulation of Cancer Hallmarks and Oncogenic Signaling.

    PubMed

    Nagini, Siddavaram

    2014-01-01

    Neem (Azadirachta indica A. Juss) is one of the most versatile medicinal plants, widely distributed in the Indian subcontinent. Neem is a rich source of limonoids that are endowed with potent medicinal properties predominantly antioxidant, anti-inflammatory, and anticancer activities. Azadirachtin, gedunin, and nimbolide are more extensively investigated relative to other neem limonoids. Accumulating evidence indicates that the anticancer effects of neem limonoids are mediated through the inhibition of hallmark capabilities of cancer such as cell proliferation, apoptosis evasion, inflammation, invasion, and angiogenesis. The neem limonoids have been demonstrated to target oncogenic signaling kinases and transcription factors chiefly, NF-κB, Wnt/β-catenin, PI3K/Akt, MAPK, and JAK/STAT signaling pathways. Neem limonoids that target multiple pathways that are aberrant in cancer are ideal candidates for cancer chemoprevention and therapy. PMID:27102702

  16. Neem Limonoids as Anticancer Agents: Modulation of Cancer Hallmarks and Oncogenic Signaling.

    PubMed

    Nagini, Siddavaram

    2014-01-01

    Neem (Azadirachta indica A. Juss) is one of the most versatile medicinal plants, widely distributed in the Indian subcontinent. Neem is a rich source of limonoids that are endowed with potent medicinal properties predominantly antioxidant, anti-inflammatory, and anticancer activities. Azadirachtin, gedunin, and nimbolide are more extensively investigated relative to other neem limonoids. Accumulating evidence indicates that the anticancer effects of neem limonoids are mediated through the inhibition of hallmark capabilities of cancer such as cell proliferation, apoptosis evasion, inflammation, invasion, and angiogenesis. The neem limonoids have been demonstrated to target oncogenic signaling kinases and transcription factors chiefly, NF-κB, Wnt/β-catenin, PI3K/Akt, MAPK, and JAK/STAT signaling pathways. Neem limonoids that target multiple pathways that are aberrant in cancer are ideal candidates for cancer chemoprevention and therapy.

  17. Toxicological evaluation of neem (Azadirachta indica) oil: acute and subacute toxicity.

    PubMed

    Deng, Yun-xia; Cao, Mei; Shi, Dong-xia; Yin, Zhong-qiong; Jia, Ren-yong; Xu, Jiao; Wang, Chuan; Lv, Cheng; Liang, Xiao-xia; He, Chang-liang; Yang, Zhi-rong; Zhao, Jian

    2013-03-01

    Neem (Azadirachta indica), popularly known as traditional medicine is a native plant in India. Neem oil is a vegetable oil derived from seeds or fruits of the neem tree through pressing or solvent extraction, and largely used in popular medicine to have antifungal, antibacterial, antimalarial, antiparasitic, anti-inflammatory, as well as immunemodulatory properties in different animal species. In the present study, acute and 28-day subacute toxicity tests were carried out. In the acute toxicity test, the LD50 values of neem oil were found to be 31.95g/kg. The subacute treatment with neem oil failed to change body weight gain, food and water consumption. Serum biochemistry analysis showed no significant differences in any of the parameters examined under the dose of 1600mg/kg/day. Histopathological exams showed that the target organs of neem oil were testicle, liver and kidneys up to the dose of 1600mg/kg/day.

  18. Toxicological evaluation of neem (Azadirachta indica) oil: acute and subacute toxicity.

    PubMed

    Deng, Yun-xia; Cao, Mei; Shi, Dong-xia; Yin, Zhong-qiong; Jia, Ren-yong; Xu, Jiao; Wang, Chuan; Lv, Cheng; Liang, Xiao-xia; He, Chang-liang; Yang, Zhi-rong; Zhao, Jian

    2013-03-01

    Neem (Azadirachta indica), popularly known as traditional medicine is a native plant in India. Neem oil is a vegetable oil derived from seeds or fruits of the neem tree through pressing or solvent extraction, and largely used in popular medicine to have antifungal, antibacterial, antimalarial, antiparasitic, anti-inflammatory, as well as immunemodulatory properties in different animal species. In the present study, acute and 28-day subacute toxicity tests were carried out. In the acute toxicity test, the LD50 values of neem oil were found to be 31.95g/kg. The subacute treatment with neem oil failed to change body weight gain, food and water consumption. Serum biochemistry analysis showed no significant differences in any of the parameters examined under the dose of 1600mg/kg/day. Histopathological exams showed that the target organs of neem oil were testicle, liver and kidneys up to the dose of 1600mg/kg/day. PMID:23353547

  19. Effects of neem limonoids on the malaria vector Anopheles stephensi Liston (Diptera: Culicidae).

    PubMed

    Nathan, Sengottayan Senthil; Kalaivani, Kandaswamy; Murugan, Kadarkarai

    2005-10-01

    The effects of the neem (Azadirachta indica A. Juss) limonoids azadirachtin, salannin, deacetylgedunin, gedunin, 17-hydroxyazadiradione and deacetylnimbin on Anopheles stephensi Liston (Diptera: Culicidae) were investigated. In exploring advantages of pure neem limonoids, we studied the larvicidal, pupicidal, adulticidal and antiovipositional activity of neem limonoids. Azadirachtin, salannin and deacetylgedunin showed high bioactivity at all doses, while the rest of the neem limonoids were less active, and were only biologically active at high doses. Azadirachtin was the most potent in all experiments and produced almost 100% larval mortality at 1 ppm concentration. In general, first to third larval instars were more susceptible to the neem limonoids. Neem products may have benefits in mosquito control programs. PMID:16112073

  20. Study on antimicrobial potential of neem oil nanoemulsion against Pseudomonas aeruginosa infection in Labeo rohita.

    PubMed

    Mishra, Prabhakar; R S, Suresh Kumar; Jerobin, Jayakumar; Thomas, John; Mukherjee, Amitava; Chandrasekaran, Natarajan

    2014-01-01

    Presence of several biochemical constituents in neem makes it an efficient antimicrobial agent for pathogenic diseases. The current investigation was aimed to assess the therapeutic potential of neem nanoemulsion as a control measure for Pseudomonas aeruginosa infection in freshwater fish Labeo rohita. The median lethal concentration (LC50) for the neem oil and neem nanoemulsion was 73.9 and 160.3 mg/L, respectively. The biomarker enzymes of treated fish tissues showed a significant difference in the level of glutathione reductase, catalase, and lipid peroxidation in neem oil-treated samples than in neem nanoemulsion-treated samples at P<0.05. The results were corroborative with histopathology and ultrastructural analysis. The bacterial infection of P. aeruginosa treated using neem nanoemulsion was more effective in both in vitro and in vivo methods. Present findings suggest that neem-based nanoemulsion has negligible toxicity to Rohu fishes. This makes neem-based nanoemulsion as an efficient therapeutic agent against P. aeruginosa infection, leading to its possible usage in the aquaculture industry.

  1. Antibacterial activity of neem nanoemulsion and its toxicity assessment on human lymphocytes in vitro.

    PubMed

    Jerobin, Jayakumar; Makwana, Pooja; Suresh Kumar, R S; Sundaramoorthy, Rajiv; Mukherjee, Amitava; Chandrasekaran, Natarajan

    2015-01-01

    Neem (Azadirachta indica) is recognized as a medicinal plant well known for its antibacterial, antimalarial, antiviral, and antifungal properties. Neem nanoemulsion (NE) (O/W) is formulated using neem oil, Tween 20, and water by high-energy ultrasonication. The formulated neem NE showed antibacterial activity against the bacterial pathogen Vibrio vulnificus by disrupting the integrity of the bacterial cell membrane. Despite the use of neem NE in various biomedical applications, the toxicity studies on human cells are still lacking. The neem NE showed a decrease in cellular viability in human lymphocytes after 24 hours of exposure. The neem NE at lower concentration (0.7-1 mg/mL) is found to be nontoxic while it is toxic at higher concentrations (1.2-2 mg/mL). The oxidative stress induced by the neem NE is evidenced by the depletion of catalase, SOD, and GSH levels in human lymphocytes. Neem NE showed a significant increase in DNA damage when compared to control in human lymphocytes (P<0.05). The NE is an effective antibacterial agent against the bacterial pathogen V. vulnificus, and it was found to be nontoxic at lower concentrations to human lymphocytes.

  2. Antibacterial activity of neem nanoemulsion and its toxicity assessment on human lymphocytes in vitro

    PubMed Central

    Jerobin, Jayakumar; Makwana, Pooja; Suresh Kumar, RS; Sundaramoorthy, Rajiv; Mukherjee, Amitava; Chandrasekaran, Natarajan

    2015-01-01

    Neem (Azadirachta indica) is recognized as a medicinal plant well known for its antibacterial, antimalarial, antiviral, and antifungal properties. Neem nanoemulsion (NE) (O/W) is formulated using neem oil, Tween 20, and water by high-energy ultrasonication. The formulated neem NE showed antibacterial activity against the bacterial pathogen Vibrio vulnificus by disrupting the integrity of the bacterial cell membrane. Despite the use of neem NE in various biomedical applications, the toxicity studies on human cells are still lacking. The neem NE showed a decrease in cellular viability in human lymphocytes after 24 hours of exposure. The neem NE at lower concentration (0.7–1 mg/mL) is found to be nontoxic while it is toxic at higher concentrations (1.2–2 mg/mL). The oxidative stress induced by the neem NE is evidenced by the depletion of catalase, SOD, and GSH levels in human lymphocytes. Neem NE showed a significant increase in DNA damage when compared to control in human lymphocytes (P<0.05). The NE is an effective antibacterial agent against the bacterial pathogen V. vulnificus, and it was found to be nontoxic at lower concentrations to human lymphocytes. PMID:26491309

  3. Study on antimicrobial potential of neem oil nanoemulsion against Pseudomonas aeruginosa infection in Labeo rohita.

    PubMed

    Mishra, Prabhakar; R S, Suresh Kumar; Jerobin, Jayakumar; Thomas, John; Mukherjee, Amitava; Chandrasekaran, Natarajan

    2014-01-01

    Presence of several biochemical constituents in neem makes it an efficient antimicrobial agent for pathogenic diseases. The current investigation was aimed to assess the therapeutic potential of neem nanoemulsion as a control measure for Pseudomonas aeruginosa infection in freshwater fish Labeo rohita. The median lethal concentration (LC50) for the neem oil and neem nanoemulsion was 73.9 and 160.3 mg/L, respectively. The biomarker enzymes of treated fish tissues showed a significant difference in the level of glutathione reductase, catalase, and lipid peroxidation in neem oil-treated samples than in neem nanoemulsion-treated samples at P<0.05. The results were corroborative with histopathology and ultrastructural analysis. The bacterial infection of P. aeruginosa treated using neem nanoemulsion was more effective in both in vitro and in vivo methods. Present findings suggest that neem-based nanoemulsion has negligible toxicity to Rohu fishes. This makes neem-based nanoemulsion as an efficient therapeutic agent against P. aeruginosa infection, leading to its possible usage in the aquaculture industry. PMID:24502533

  4. Antibacterial activity of neem nanoemulsion and its toxicity assessment on human lymphocytes in vitro.

    PubMed

    Jerobin, Jayakumar; Makwana, Pooja; Suresh Kumar, R S; Sundaramoorthy, Rajiv; Mukherjee, Amitava; Chandrasekaran, Natarajan

    2015-01-01

    Neem (Azadirachta indica) is recognized as a medicinal plant well known for its antibacterial, antimalarial, antiviral, and antifungal properties. Neem nanoemulsion (NE) (O/W) is formulated using neem oil, Tween 20, and water by high-energy ultrasonication. The formulated neem NE showed antibacterial activity against the bacterial pathogen Vibrio vulnificus by disrupting the integrity of the bacterial cell membrane. Despite the use of neem NE in various biomedical applications, the toxicity studies on human cells are still lacking. The neem NE showed a decrease in cellular viability in human lymphocytes after 24 hours of exposure. The neem NE at lower concentration (0.7-1 mg/mL) is found to be nontoxic while it is toxic at higher concentrations (1.2-2 mg/mL). The oxidative stress induced by the neem NE is evidenced by the depletion of catalase, SOD, and GSH levels in human lymphocytes. Neem NE showed a significant increase in DNA damage when compared to control in human lymphocytes (P<0.05). The NE is an effective antibacterial agent against the bacterial pathogen V. vulnificus, and it was found to be nontoxic at lower concentrations to human lymphocytes. PMID:26491309

  5. Bioactivity of neem, Azadirachta indica, against spittlebug Mahanarva fimbriolata (Hemiptera: Cercopidae) on sugarcane.

    PubMed

    Garcia, José Francisco; Grisoto, Eliane; Vendramim, José Djair; Botelho, Paulo Sérgio Machado

    2006-12-01

    The effect of neem, Azadirachta indica A. Juss, on some biological parameters of Mahanarva fimbriolata (Stil) (Hemiptera: Cercopidae) was studied in the laboratory by using NeemAzal-T/S, Nimkol-LS, and an aqueous neem seed extract. Initially, the LC,, was estimated for nymphs. Later, nymphs fed on sugarcane, Saccharum officinarum L., roots were sprayed with the respective LC,, for each product. The adults were maintained in cages on sugarcane plants sprayed at the base with the maximum rate recommended commercially for the crop (3 liter/ha). Moistened cotton discs surrounding the base of the plant were used as oviposition substrates. The LCso values estimated for NeemAzal, Nimkol, and aqueous extract were 0.014, 0.225, and 0.611%, respectively. There was a reduction in spittlebug longevity, regardless of sex, in relation to the control. Males exposed to the neem products, and aqueous extract showed longevity reductions of approximately 50%, whereas for females the reductions were 55-60%. The neem products and extract reduced fecundity by 75-85%. Morphological and physiological changes were observed in 9% of the eggs from individuals submitted to NeemAzal. Neem-based products, especially NeemAzal, have potential for the control of M. fimbriolata. PMID:17195667

  6. Argonne's SpEC Module

    SciTech Connect

    Harper, Jason

    2014-05-05

    Jason Harper, an electrical engineer in Argonne National Laboratory's EV-Smart Grid Interoperability Center, discusses his SpEC Module invention that will enable fast charging of electric vehicles in under 15 minutes. The module has been licensed to BTCPower.

  7. Argonne's SpEC Module

    ScienceCinema

    Harper, Jason

    2016-07-12

    Jason Harper, an electrical engineer in Argonne National Laboratory's EV-Smart Grid Interoperability Center, discusses his SpEC Module invention that will enable fast charging of electric vehicles in under 15 minutes. The module has been licensed to BTCPower.

  8. Murine carcinoma expressing carcinoembryonic antigen-like protein is restricted by antibody against neem leaf glycoprotein.

    PubMed

    Das, Arnab; Barik, Subhasis; Bose, Anamika; Roy, Soumyabrata; Biswas, Jaydip; Baral, Rathindranath; Pal, Smarajit

    2014-11-01

    We have generated a polyclonal antibody against a novel immunomodulator, neem leaf glycoprotein (NLGP) that can react to a specific 47 kDa subunit of NLGP. Generated anti-NLGP antibody (primarily IgG2a) was tested for its anti-tumor activity in murine carcinoma (EC, CT-26), sarcoma (S180) and melanoma (B16Mel) tumor models. Surprisingly, tumor growth restriction was only observed in CT-26 carcinoma models, without any alteration in other tumor systems. Comparative examination of antigenicity between four different tumor models revealed high expression of CEA-like protein on the surface of CT-26 tumors. Subsequent examination of the cross-reactivity of anti-NLGP antibody with purified or cell bound CEA revealed prominent recognition of CEA by anti-NLGP antibody, as detected by ELISA, Western Blotting and immunohistochemistry. This recognition seems to be responsible for anti-tumor function of anti-NLGP antibody only on CEA-like protein expressing CT-26 tumor models, as confirmed by ADCC reaction in CEA(+) tumor systems where dependency to anti-NLGP antibody is equivalent to anti-CEA antibody. Obtained result with enormous therapeutic potential for CEA(+) tumors may be explained in view of the epitope spreading concept, however, further investigation is crucial.

  9. 40 CFR 180.1161 - Clarified hydrophobic extract of neem oil; exemption from the requirement of a tolerance.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Clarified hydrophobic extract of neem oil; exemption from the requirement of a tolerance. 180.1161 Section 180.1161 Protection of... neem oil; exemption from the requirement of a tolerance. Clarified hydrophobic extract of neem oil...

  10. 40 CFR 180.1161 - Clarified hydrophobic extract of neem oil; exemption from the requirement of a tolerance.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 24 2011-07-01 2011-07-01 false Clarified hydrophobic extract of neem oil; exemption from the requirement of a tolerance. 180.1161 Section 180.1161 Protection of... neem oil; exemption from the requirement of a tolerance. Clarified hydrophobic extract of neem oil...

  11. 40 CFR 180.1161 - Clarified hydrophobic extract of neem oil; exemption from the requirement of a tolerance.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... neem oil; exemption from the requirement of a tolerance. Clarified hydrophobic extract of neem oil is... 40 Protection of Environment 24 2014-07-01 2014-07-01 false Clarified hydrophobic extract of neem oil; exemption from the requirement of a tolerance. 180.1161 Section 180.1161 Protection...

  12. 40 CFR 180.1161 - Clarified hydrophobic extract of neem oil; exemption from the requirement of a tolerance.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 25 2013-07-01 2013-07-01 false Clarified hydrophobic extract of neem... PESTICIDE CHEMICAL RESIDUES IN FOOD Exemptions From Tolerances § 180.1161 Clarified hydrophobic extract of neem oil; exemption from the requirement of a tolerance. Clarified hydrophobic extract of neem oil...

  13. 40 CFR 180.1161 - Clarified hydrophobic extract of neem oil; exemption from the requirement of a tolerance.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 25 2012-07-01 2012-07-01 false Clarified hydrophobic extract of neem... PESTICIDE CHEMICAL RESIDUES IN FOOD Exemptions From Tolerances § 180.1161 Clarified hydrophobic extract of neem oil; exemption from the requirement of a tolerance. Clarified hydrophobic extract of neem oil...

  14. Alternative insecticides: an urgent need.

    PubMed

    Zaim, Morteza; Guillet, Pierre

    2002-04-01

    Most insecticides used against pests and vectors of human disease (e.g. fleas, flies and mosquitoes) are spin-offs from agrochemical research and development. The arsenal of safe and cost-effective public health insecticides is being depleted by restrictions for various reasons (e.g. insecticide resistance, unacceptable side effects and non re-registration) and the number of new products launched is dwindling. Mobilizing public resources and establishment of partnerships to support research and development of public health insecticides is crucial in the post-DDT and post-pyrethroid era.

  15. Deformation of Eemian and Glacial ice at NEEM, Greenland

    NASA Astrophysics Data System (ADS)

    Keegan, Kaitlin; Dahl-Jensen, Dorthe; Montagnat, Maurine; Weikusat, Ilka; Kipfstuhl, Sepp

    2015-04-01

    New findings from deep Greenland ice cores and airborne radio echo sounding (RES) images show that basal ice flow is very unstable, and a basal layer of disturbed ice is often observed. At NEEM, Greenland this folding occurs at the boundary between the Eemian and glacial ice regimes, suggesting that differences in physical properties of the ice play a role in the disturbance. Past work in metallurgy (Burke, 1957) and ice (Hammer et al., 1978; Langway et al., 1988; Dahl-Jensen et al., 1997), suggests that impurity content controls grain evolution, and therefore deformation, which we hypothesize to be analogous to the differences in ice flow seen deep in the NEEM ice core. Here we present results of fabric, grain size, impurity content, and deformation studies from samples above and below this unstable boundary in the ice sheet.

  16. Deformation Studies of NEEM, Greenland Basal Folded Ice

    NASA Astrophysics Data System (ADS)

    Keegan, K.; Dahl-Jensen, D.; Montagnat, M.; Weikusat, I.

    2015-12-01

    Deep Greenland ice cores and airborne radio echo sounding (RES) images have recently revealed that basal ice flow of the Greenland Ice Sheet is very unstable. In many locations, a basal layer of disturbed ice is observed. At the NEEM, Greenland site this folding occurs at the boundary between the Eemian and glacial ice regimes, indicating that differences in physical properties of the ice play a role in the disturbance. Past work in metallurgy and ice suggests that impurity content controls grain evolution and therefore deformation. We hypothesize that the differences in ice flow seen deep in the NEEM ice core are controlled by differences in the impurity content of the ice layers. Here we present results of fabric, grain size, impurity content, and deformation studies from samples above and below this unstable boundary in the ice sheet.

  17. Antiplasmodial triterpenoids from the fruits of neem, Azadirachta indica.

    PubMed

    Chianese, Giuseppina; Yerbanga, Serge R; Lucantoni, Leonardo; Habluetzel, Annette; Basilico, Nicoletta; Taramelli, Donatella; Fattorusso, Ernesto; Taglialatela-Scafati, Orazio

    2010-08-27

    Eight known and two new triterpenoid derivatives, neemfruitins A (9) and B (10), have been isolated from the fruits of neem, Azadirachta indica, a traditional antimalarial plant used by Asian and African populations. In vitro antiplasmodial tests evidenced a significant activity of the known gedunin and azadirone and the new neemfruitin A and provided useful information about the structure-antimalarial activity relationships in the limonoid class. PMID:20669933

  18. Toxicological studies on debitterized Neem oil (Azadirachta indica).

    PubMed

    Chinnasamy, N; Harishankar, N; Kumar, P U; Rukmini, C

    1993-04-01

    Azadirachta indica, popularly known as 'Neem' in India, is widely grown all over the tropics. The seed contains 45% oil and is a minor oil of considerable potential. Neem oil is bitter and inedible. Recently, a method has been developed to completely remove the bitter and odoriferous principles and leave a bitterless, odourless and colourless oil. The nutritional and chemical evaluation of debitterized neem oil (NO) was reported earlier (C. Rukmini, Food Chemistry 1987, 26, 119). We report here a three-generation study, carried out according to WHO/FDA protocol in groups of 15 male and 15 female rats fed a diet containing 10% NO or groundnut oil (GNO). Reproductive toxicology was monitored for three generations. The results obtained in both the matings in all the three generations did not show any adverse effects on the reproductive parameters studied in rats fed NO and were similar to those observed in rats fed GNO. The mean organ weights and the histopathological evaluation of all the organs were similar to those of the control (GNO-fed) rats. A mutagenicity test of NO was also found to be negative in Ames test as reported earlier (K. Polasa and C. Rukmini, Food and Chemical Toxicology 1987, 25, 763). These studies indicate that NO devoid of all the bitter and odoriferous principles, may be recommended as safe for consumption by humans. PMID:8477918

  19. Horizontal Transfer of Diatomaceous Earth and Botanical Insecticides in the Common Bed Bug, Cimex lectularius L.; Hemiptera: Cimicidae

    PubMed Central

    Akhtar, Yasmin; Isman, Murray B.

    2013-01-01

    Background Horizontal transfer of insecticide occurs when insects contact or ingest an insecticide, return to an aggregation or a nest, and transfer the insecticide to other conspecific insects through contact. This phenomenon has been reported in a number of insects including social insects, however it has not been reported in bed bugs. Since horizontal transfer can facilitate the spread of insecticide into hard to reach spaces, it could contribute greatly to the management of these public health pests. Methodology/Results To demonstrate horizontal transfer of diatomaceous earth and botanical insecticides in C. lectularius, an exposed (donor) bed bug, following a 10-minute acquisition period, was placed with unexposed (recipient) bed bugs. Mortality data clearly demonstrates that diatomaceous earth (DE 51) was actively transferred from a single exposed bug to unexposed bugs in a concentration dependent manner. LC50 values varied from 24.4 mg at 48 h to 5.1 mg at 216 h when a single exposed bed bug was placed with 5 unexposed bed bugs. LT50 values also exhibited a concentration response. LT50 values varied from 1.8 days to 8.4 days when a ‘donor’ bug exposed to 20 and 5 mg of dust respectively was placed with 5 ‘recipient’ bugs. Dust was also actively transferred from adult bed bugs to the nymphs. In addition we observed horizontal transfer of botanical insecticides including neem, ryania, and rotenone to varying degrees. Conclusion/Significance Our data clearly demonstrate horizontal transfer of diatomaceous earth and botanical insecticides in the common bed bug, C. lectularius. Use of a fluorescent dust provided visual confirmation that contaminated bed bugs transfer dust to untreated bed bugs in harborage. This result is important because bedbugs live in hard-to-reach places and interaction between conspecifics can be exploited for delivery and dissemination of management products directed at this public health pest. PMID:24086593

  20. Mutagenic and cytotoxic activities of benfuracarb insecticide.

    PubMed

    Eren, Yasin; Erdoğmuş, Sevim Feyza; Akyıl, Dilek; Özkara, Arzu

    2016-08-01

    Benfuracarb is a carbamate insecticide used to control insect pests in vegetables and it has anti-acetylcholinesterase activity lower than other carbamates. Cytotoxic effects of benfuracarb were evaluated by using root growth inhibition (EC50), mitotic index (MI), and mitotic phase determinations on the root meristem cells of Allium cepa and mutagenic effects were determined in Salmonella typhymurium Ames test by TA98 and TA100 strains with and without metabolic activation. In Allium test, 1 % DMSO was used as negative control group and 10 ppm MMS was used as positive control group. 75 ppm concentration of benfuracarb was found as EC50. In MI and mitotic phases determination study, 37.5, 75 and 150 ppm doses of benfuracarb were used. Dose-dependent cytotoxic activity was found by root growth inhibition and MI studies. It was identified that mitotic inhibition activity of benfuracarb was higher than 10 ppm MMS. In Ames test, mutagenic activity was not observed and over 200 µg/plate of benfuracarb was determined as cytotoxic to S. typhymurium strains. Benfuracarb can be called as "mitotic inhibitor" but not called as mutagen. PMID:25381170

  1. Mechanism of neem limonoids-induced cell death in cancer: Role of oxidative phosphorylation.

    PubMed

    Yadav, Neelu; Kumar, Sandeep; Kumar, Rahul; Srivastava, Pragya; Sun, Leimin; Rapali, Peter; Marlowe, Timothy; Schneider, Andrea; Inigo, Joseph R; O'Malley, Jordan; Londonkar, Ramesh; Gogada, Raghu; Chaudhary, Ajay K; Yadava, Nagendra; Chandra, Dhyan

    2016-01-01

    We have previously reported that neem limonoids (neem) induce multiple cancer cell death pathways. Here we dissect the underlying mechanisms of neem-induced apoptotic cell death in cancer. We observed that neem-induced caspase activation does not require Bax/Bak channel-mediated mitochondrial outer membrane permeabilization, permeability transition pore, and mitochondrial fragmentation. Neem enhanced mitochondrial DNA and mitochondrial biomass. While oxidative phosphorylation (OXPHOS) Complex-I activity was decreased, the activities of other OXPHOS complexes including Complex-II and -IV were unaltered. Increased reactive oxygen species (ROS) levels were associated with an increase in mitochondrial biomass and apoptosis upon neem exposure. Complex-I deficiency due to the loss of Ndufa1-encoded MWFE protein inhibited neem-induced caspase activation and apoptosis, but cell death induction was enhanced. Complex II-deficiency due to the loss of succinate dehydrogenase complex subunit C (SDHC) robustly decreased caspase activation, apoptosis, and cell death. Additionally, the ablation of Complexes-I, -III, -IV, and -V together did not inhibit caspase activation. Together, we demonstrate that neem limonoids target OXPHOS system to induce cancer cell death, which does not require upregulation or activation of proapoptotic Bcl-2 family proteins.

  2. Botanical insecticides, deterrents, and repellents in modern agriculture and an increasingly regulated world.

    PubMed

    Isman, Murray B

    2006-01-01

    Botanical insecticides have long been touted as attractive alternatives to synthetic chemical insecticides for pest management because botanicals reputedly pose little threat to the environment or to human health. The body of scientific literature documenting bioactivity of plant derivatives to arthropod pests continues to expand, yet only a handful of botanicals are currently used in agriculture in the industrialized world, and there are few prospects for commercial development of new botanical products. Pyrethrum and neem are well established commercially, pesticides based on plant essential oils have recently entered the marketplace, and the use of rotenone appears to be waning. A number of plant substances have been considered for use as insect antifeedants or repellents, but apart from some natural mosquito repellents, little commercial success has ensued for plant substances that modify arthropod behavior. Several factors appear to limit the success of botanicals, most notably regulatory barriers and the availability of competing products (newer synthetics, fermentation products, microbials) that are cost-effective and relatively safe compared with their predecessors. In the context of agricultural pest management, botanical insecticides are best suited for use in organic food production in industrialized countries but can play a much greater role in the production and postharvest protection of food in developing countries. PMID:16332203

  3. Content of trace elements and chromium speciation in Neem powder and tea infusions.

    PubMed

    Novotnik, Breda; Zuliani, Tea; Ščančar, Janez; Milačič, Radmila

    2015-01-01

    Total concentrations of selected trace elements in Neem powder and in Neem tea were determined by inductively coupled plasma mass spectrometry (ICP-MS). The data revealed that despite high total concentrations of the potentially toxic elements Al and Ni in Neem powder, their amounts dissolved in Neem tea were low. Total concentrations of the other toxic elements Pb, As and Cd were also very low and do not represent a health hazard. In contrast, total concentrations of the essential elements Fe, Cu, Zn, Se Mo and Cr in Neem powder were high and also considerable in Neem tea. Consuming one cup of Neem tea (2g per 200 mL of water) covers the recommended daily intakes for Cr and Se and represents an important source of Mo and Cu. Speciation analysis of Cr by high performance liquid chromatography (HPLC) coupled to ICP-MS with the use of enriched Cr isotopic tracers to follow species interconversions during the analytical procedure demonstrated that toxic Cr(VI) was not present either in Neem powder or in Neem tea. Its concentrations were below the limits of detection of the HPLC-ICP-MS procedure applied. The speciation analysis data confirmed that even Cr(VI) was added, it was rapidly reduced by the presence of antioxidants in Neem leaves. By the use of enriched Cr isotopic spike solutions it was also demonstrated that for obtaining reliable analytical data it is essential to apply the extraction procedures which prevent Cr species interconversions, or to correct for species transformation.

  4. Content of trace elements and chromium speciation in Neem powder and tea infusions.

    PubMed

    Novotnik, Breda; Zuliani, Tea; Ščančar, Janez; Milačič, Radmila

    2015-01-01

    Total concentrations of selected trace elements in Neem powder and in Neem tea were determined by inductively coupled plasma mass spectrometry (ICP-MS). The data revealed that despite high total concentrations of the potentially toxic elements Al and Ni in Neem powder, their amounts dissolved in Neem tea were low. Total concentrations of the other toxic elements Pb, As and Cd were also very low and do not represent a health hazard. In contrast, total concentrations of the essential elements Fe, Cu, Zn, Se Mo and Cr in Neem powder were high and also considerable in Neem tea. Consuming one cup of Neem tea (2g per 200 mL of water) covers the recommended daily intakes for Cr and Se and represents an important source of Mo and Cu. Speciation analysis of Cr by high performance liquid chromatography (HPLC) coupled to ICP-MS with the use of enriched Cr isotopic tracers to follow species interconversions during the analytical procedure demonstrated that toxic Cr(VI) was not present either in Neem powder or in Neem tea. Its concentrations were below the limits of detection of the HPLC-ICP-MS procedure applied. The speciation analysis data confirmed that even Cr(VI) was added, it was rapidly reduced by the presence of antioxidants in Neem leaves. By the use of enriched Cr isotopic spike solutions it was also demonstrated that for obtaining reliable analytical data it is essential to apply the extraction procedures which prevent Cr species interconversions, or to correct for species transformation. PMID:26004899

  5. Anticholinesterase insecticide poisoning.

    PubMed

    Mackey, C L

    1982-01-01

    Anticholinesterase insecticides can be lethal, especially to small children. Prevention, not treatment, is the key to lowering the mortality rate. However, treatment, when necessary, can be effective if the poisoning agent is identified quickly as an anticholinesterase insecticide and therapy is begun immediately and aggressively. Large doses (up to 5 gm) of atropine, which block the parasympathetic effects of the poison, in conjunction with pralidoxime, a cholinesterase regenerator, need to be administered, second only in priority to establishing an airway. The second line of attack after adequate atropinization is supportive. Assistance with ventilation is individualized according to the degree of patient need. Intake with cautiously vigorous fluid therapy and output via Foley catheter are essential. Gastric lavage, seizure precautions and control as necessary, good body hygiene, and frequent turning are also part of necessary nursing intervention. Prognosis is fairly good if improvement is shown after therapy is begun. Maintaining adequate atropinization seems to be difficult yet essential to the success of the treatment and a good prognosis for the patient. PMID:6921196

  6. Physiological and biochemical effect of neem and other Meliaceae plants secondary metabolites against Lepidopteran insects

    PubMed Central

    Senthil-Nathan, Sengottayan

    2013-01-01

    This review described the physiological and biochemical effects of various secondary metabolites from Meliaceae against major Lepidopteran insect pest including, Noctuidae and Pyralidae. The biochemical effect of major Meliaceae secondary metabolites were discussed more in this review. Several enzymes based on food materials have critical roles in nutritional indices (food utilization) of the insect pest population. Several research work has been referred and the effect of Meliaceae secondary metabolites on feeding parameters of insects by demonstrating food consumption, approximate digestibility of consumed food, efficiency of converting the ingested food to body substance, efficiency of converting digested food to body substance and consumption index was reviewed in detail. Further how the digestive enzymes including a-Amylases, α and β-glucosidases (EC 3.2.1.1), lipases (EC 3.1.1) Proteases, serine, cysteine, and aspartic proteinases affected by the Meliaceae secondary metabolites was reviewed. Further effect of Meliaceae secondary metabolites on detoxifying enzymes have been found to react against botanical insecticides including general esterases (EST), glutathione S-transferase (GST) and phosphatases was reviewed. Alkaline phosphatase (ALP, E.C.3.1.3.1) and acid phosphatase (ACP, E.C.3.1.3.2) are hydrolytic enzymes, which hydrolyze phosphomonoesters under alkaline or acid conditions, respectively. These enzymes were affected by the secondary metabolites treatment. The detailed mechanism of action was further explained in this review. Acethylcholine esterase (AChE) is a key enzyme that terminates nerve impulses by catalyzing the hydrolysis of neurotransmitter, acetylcholine, in the nervous system of various organisms. How the AChE activity was altered by the Meliaceae secondary metabolites reviewed in detail. PMID:24391591

  7. Neurotoxicity of neem commercial formulation (Azadirachta indica A. Juss) in adult zebrafish (Danio rerio).

    PubMed

    Bernardi, M M; Dias, S G; Barbosa, V E

    2013-11-01

    The neurotoxic effects of a commercial formulation of Azadirachta indica A. Juss, also called neem or nim, in adult zebrafish were determined using behavioral models. General activity, anxiety-like effects, and learning and memory in a passive avoidance task were assessed after exposure to 20 or 40 μl/L neem. The results showed that 20 μl/L neem reduced the number of runs. Both neem concentrations increased the number of climbs to the water surface, and 40 μl/L increased the number of tremors. In the anxiety test, the 20 μl/L dose increased the number of entries in the light side compared with controls, but the latency to enter the dark side and the freezing behavior in this side did not changed. In relation to controls, the 40 μl/L neem reduced the latency to enter in the light side, did not change the number of entries in this side and increased freezing behavior in the light side. In the passive avoidance test, pre-training and pre-test neem exposure to 40 μl/L decreased the response to the learning task. Thus, no impairment was observed in this behavioral test. We conclude that neem reduced general activity and increased anxiety-like behavior but did not affect learning and memory.

  8. Neurotoxicity of neem commercial formulation (Azadirachta indica A. Juss) in adult zebrafish (Danio rerio).

    PubMed

    Bernardi, M M; Dias, S G; Barbosa, V E

    2013-11-01

    The neurotoxic effects of a commercial formulation of Azadirachta indica A. Juss, also called neem or nim, in adult zebrafish were determined using behavioral models. General activity, anxiety-like effects, and learning and memory in a passive avoidance task were assessed after exposure to 20 or 40 μl/L neem. The results showed that 20 μl/L neem reduced the number of runs. Both neem concentrations increased the number of climbs to the water surface, and 40 μl/L increased the number of tremors. In the anxiety test, the 20 μl/L dose increased the number of entries in the light side compared with controls, but the latency to enter the dark side and the freezing behavior in this side did not changed. In relation to controls, the 40 μl/L neem reduced the latency to enter in the light side, did not change the number of entries in this side and increased freezing behavior in the light side. In the passive avoidance test, pre-training and pre-test neem exposure to 40 μl/L decreased the response to the learning task. Thus, no impairment was observed in this behavioral test. We conclude that neem reduced general activity and increased anxiety-like behavior but did not affect learning and memory. PMID:24211596

  9. The efficacy of neem seed extracts (Tre-san, MiteStop on a broad spectrum of pests and parasites.

    PubMed

    Schmahl, Günter; Al-Rasheid, Khaled A S; Abdel-Ghaffar, Fathy; Klimpel, Sven; Mehlhorn, Heinz

    2010-07-01

    The paper summarizes the acaricidal and insecticidal effects of a patented neem seed extract when diluted 1:10 with shampoo or 1:20, 1:30, 1:33, 1:40, respectively, 1:66 with tap water. It was shown that a broad range of pests and parasites, such as house dust mites, poultry mites, harvest mites, Ixodes and Rhipicephalus ticks, cat fleas (adults, larvae), bed bugs (all stages), head lice and mallophaga, cockroaches (genera Blatta, Blattella, Gomphadorhina), raptor bugs (Triatoma), and even food-attacking beetle (Tenebrio molitor) might be controlled with this extract, which is available as Tre-san (against house dust mites) and MiteStop (against mites, ticks, insects of any kind) to become water diluted or as Wash Away Louse or Picksan LouseStop being diluted in a shampoo. Tests on skin compatibility proved that there are no skin irritations during or after use. However, some target species are less sensible (beetles, Triatoma stages, fly maggots), while the specimens of the other species cited above were successfully killed even at low concentrations of the extract. PMID:20461406

  10. Mouse sperm-egg interaction in vitro in the presence of neem oil.

    PubMed

    Juneja, S C; Williams, R S

    1993-01-01

    In vitro evidence is presented showing toxicity of neem oil on sperm-egg interaction in mouse. Cumulus oophorus-enclosed ova, inseminated with capacitated spermatozoa, were cultured in 1 ml of in vitro fertilization (IVF) medium and overlayered by 1 ml of different concentrations of neem oil (1, 5, 10, 25, 50 and 100%) for IVF duration of 4h. At the end of incubation, ova were allowed to grow in neem oil-free culture medium and assessed for fertilization, first cleavage (2-cell formation) and blastocyst formation in vitro at 4-14h, 24h and 108h post-insemination respectively. The study showed that the presence of neem oil at concentrations of 10, 25 and 50% caused inhibition of IVF in a dose-dependent manner. The toxic effect of exposure of 25 and 50% neem oil was further carried over to the first cleavage of the resulting fertilized ova and the toxic effect of 5, 10, 25 and 50% was carried over to the blastocyst formation from the resulting fertilized ova when grown in neem-oil free culture medium. A total of 94.1% inhibition of 2-cell formation and 100% inhibition of blastocyst formation from the inseminated ova was observed in 50 and 25% neem oil-treated groups respectively. Neem oil at 100% concentration caused 100% degeneration of ova at 1h of sperm-ova coculture. The study showed a direct toxic effect of neem oil on sperm-egg interaction in vitro and encourages research investigations of this herbal product as a pre-coital contraceptive. PMID:8231626

  11. A renaissance for botanical insecticides?

    PubMed

    Isman, Murray B

    2015-12-01

    Botanical insecticides continue to be a subject of keen interest among the international research community, reflected in the steady growth in scientific publications devoted to the subject. Until very recently though, the translation of that theory to practice, i.e. the commercialisation and adoption of new botanical insecticides in the marketplace, has seriously lagged behind. Strict regulatory regimes, long the bane of small pesticide producers, are beginning to relax some of the data requirements for 'low-risk' pesticide products, facilitating movement of more botanicals into the commercial arena. In this paper I discuss some of the jurisdictions where botanicals are increasingly finding favour, some of the newer botanical insecticides in the plant and animal health arsenal and some of the specific sectors where botanicals are most likely to compete effectively with other types of insecticidal product.

  12. A renaissance for botanical insecticides?

    PubMed

    Isman, Murray B

    2015-12-01

    Botanical insecticides continue to be a subject of keen interest among the international research community, reflected in the steady growth in scientific publications devoted to the subject. Until very recently though, the translation of that theory to practice, i.e. the commercialisation and adoption of new botanical insecticides in the marketplace, has seriously lagged behind. Strict regulatory regimes, long the bane of small pesticide producers, are beginning to relax some of the data requirements for 'low-risk' pesticide products, facilitating movement of more botanicals into the commercial arena. In this paper I discuss some of the jurisdictions where botanicals are increasingly finding favour, some of the newer botanical insecticides in the plant and animal health arsenal and some of the specific sectors where botanicals are most likely to compete effectively with other types of insecticidal product. PMID:26251334

  13. 6beta-hydroxygedunin from Azadirachta indica. Its potentiation effects with some non-azadirachtin limonoids in neem against lepidopteran larvae.

    PubMed

    Koul, Opender; Multani, Jatinder Singh; Singh, Gurmeet; Daniewski, Wlodzimierz Maria; Berlozecki, Stanislaw

    2003-05-01

    The biological activity of 6beta-hydroxygedunin isolated from Azadirachta indica A. Juss. was assessed using the gram pod borer, Helicoverpa armigera (Hubner), and Asian armyworm, Spodoptera litura (Fabricius) (Lepidoptera: Noctuidae), alone and in combination with other limonoids, gedunin, salannin, nimbinene, and azadirachtin. The compound exhibited growth inhibitory activity in artificial diet bioassays, with 24.2 and 21.5 ppm, respectively, inhibiting growth by 50%. This efficacy was higher in comparison to gedunin (EC(50) = 50.8 and 40.4 ppm), salannin (EC(50) = 74.5 and 72.0 ppm), and nimbinene (EC(50) = 391.4 and 404.5 ppm). Azadirachtin, however, remained the most active neem allelochemical against both insect species. Nutritional assays clearly demonstrated that, though relative consumption and growth rates of fourth instar larvae were reduced, gedunin-type compounds induced physiological toxicity, evident by reduced efficiency of conversion of ingested food (ECI) in feeding experiments. Salannin and nimbinene, on the contrary, induced concentration-dependent feeding deterrence only. In feeding experiments, combinations of the compounds revealed that when azadirachtin was present in a mixture, EC(50) values did not deviate from the individual efficacy of azadirachtin (0.26 and 0.21 ppm, respectively) against H. armigera and S. litura larvae. However, a combination without azadirachtin did show a potentiation effect with potent EC(50) values among structurally different molecules, i.e., when salannin or nimbinene was combined with 6beta-hydroxygedunin or gedunin rather than structurally similar salannin + nimbinene or 6beta-hydroxygedunin + gedunin. Obviously, azadirachtin being the most active compound in neem is not synergized or influenced by any other limonoid, but other non-azadirachtin limonoids were more potent in specific combinations vis-à-vis the structural chemistry of the compound. It is obvious from the present study that potentiation among

  14. Professional and consumer insecticides for management of adult Japanese beetle on hybrid tea rose.

    PubMed

    Gupta, Garima; Krischik, Vera A

    2007-06-01

    In many states, Japanese beetle, Popilliajaponica Newman (Coleoptera: Scarabeidae), is no longer quarantined, and management is left to professional applicators and consumers. Adult management in hybrid tea rose, Rosa L., was compared among biorational insecticides, novel imidacloprid applications (tablet, gel, and root dip), and conventional insecticides. Efficacy of biorational insecticides used by consumers varied widely and may not offer predictable management: mortality was 3.0% with Garlic Barrier, 5.0% with Monterey Neem Oil, 15.1% with Pygenic (1.4% pyrethrins), and 27.3% with Orange Guard (D-limonene). Only JB Killer (0.02% pyrethrins plus 0.2% piperonyl butoxide) had mortality of 90.9%, probably due to piperonyl butoxide. Professional biorationals did not show significant mortality: 7.7% with Azatin XL (azadirachtin) and 3.7% Conserve (spinosad). In contrast, conventional insecticides demonstrated significant mortality; 88.4% with Decathlon 20 WP (cyfluthrin) and 83.3% with Discus SC (imidacloprid plus cyfluthrin). New imidacloprid applications (tablet, gel, and root dip) worked as well as standard drench and granular methods, but they showed 9.1-42.7% mortality. However, beetles were incapacitated as demonstrated by inability to walk (82-106-s flip time) compared with controls (30-s flip time). No phytotoxicity was observed in any treatments. However, some imidacloprid treatments produced growth enhancement: higher leaf chlorophyll (1X, 3X granular, and one tablet), and larger leaf area and higher nitrogen (3X granular, drench). The highest (active ingredient) imidacloprid was in 3X granular treatment, which in an unplanned infestation, showed highest numbers of twospotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae). Effects of imidacloprid on leaf quality and mite outbreaks deserves research. PMID:17598545

  15. Effects of Sequential Applications of Bassa 50EC (Fenobucarb) and Vitashield 40EC (Chlorpyrifos ethyl) on Acetylcholinesterase Activity in Climbing Perch (Anabas testudineus) Cultured in Rice Fields in the Mekong Delta, Vietnam.

    PubMed

    Tam, Nguyen Thanh; Berg, Håkan; Laureus, Jenny; Cong, Nguyen Van; Tedengren, Michael

    2016-07-01

    This study assesses the effects of sequential applications of the insecticides Bassa 50EC (fenobucarb-F) and Vitashield 40EC (chlorpyrifos ethyl-CPF), sprayed at concentrations used by rice farmers in the Mekong Delta, on the brain acetylcholinesterase (AChE) in climbing perch fingerlings. After spraying the pesticides on the rice fields, the water concentrations of both insecticides decreased below the detection levels within 3 days. The sequential applications caused significant inhibition on the brain AChE activity in the exposed fish. The inhibition by F was quicker, but less prolonged, than for CPF. The inhibition levels caused by the sequential applications were lower than those caused by only CPF and by a mixture of CPF and F. The results indicate that sequential applications of pesticides could have a negative impact on aquatic organisms and fish yields, with implication for the aquatic biodiversity, local people's livelihood and the aquaculture industry in the Mekong Delta. PMID:27075585

  16. Anticancer biology of Azadirachta indica L (neem): a mini review.

    PubMed

    Paul, Rajkumar; Prasad, Murari; Sah, Nand K

    2011-09-15

    Neem (Azadirachta indica), a member of the Meliaceae family, is a fast growing tropical evergreen tree with a highly branched and stout, solid stem. Because of its tremendous therapeutic, domestic, agricultural and ethnomedicinal significance, and its proximity with human culture and civilization, neem has been called "the wonder tree" and "nature's drug store." All parts of this tree, particularly the leaves, bark, seed-oil and their purified products are widely used for treatment of cancer. Over 60 different types of biochemicals including terpenoids and steroids have been purified from this plant. Pre-clinical research work done during the last decade has fine-tuned our understanding of the anticancer properties of the crude and purified products from this plant. The anticancer properties of the plant have been studied largely in terms of its preventive, protective, tumor-suppressive, immunomodulatory and apoptotic effects against various types of cancer and their molecular mechanisms. This review aims at scanning scattered literature on "the anticancer biology of A. indica," related toxicity problems and future perspectives. The cogent data on the anticancer biology of products from A. indica deserve multi-institutional clinical trials as early as possible. The prospects of relatively cheaper cancer drugs could then be brighter, particularly for the under-privileged cancer patients of the world. PMID:21743298

  17. The preparation of neem oil microemulsion (Azadirachta indica) and the comparison of acaricidal time between neem oil microemulsion and other formulations in vitro.

    PubMed

    Xu, Jiao; Fan, Qiao-Jia; Yin, Zhong-Qiong; Li, Xu-Ting; Du, Yong-Hua; Jia, Ren-Yong; Wang, Kai-Yu; Lv, Cheng; Ye, Gang; Geng, Yi; Su, Gang; Zhao, Ling; Hu, Ting-Xiu; Shi, Fei; Zhang, Li; Wu, Chang-Long; Tao, Cui; Zhang, Ya-Xue; Shi, Dong-Xia

    2010-05-11

    The preparation of neem oil microemulsion and its acaricidal activity in vitro was developed in this study. In these systems, the mixture of Tween-80 and the sodium dodecyl benzene sulfonate (SDBS) (4:1, by weight) was used as compound surfactant; the mixture of compound surfactant and hexyl alcohol (4:1, by weight) was used as emulsifier system; the mixture of neem oil, emulsifier system and water (1:3.5:5.5, by weight) was used as neem oil microemulsion. All the mixtures were stired in 800 rpm for 15 min at 40 degrees C. The acaricidal activity was measured by the speed of kill. The whole lethal time value of 10% neem oil microemulsion was 192.50 min against Sarcoptes scabiei var. cuniculi larvae in vitro. The median lethal time value was 81.7463 min with the toxicity regression equations of Y=-6.0269+3.1514X. These results demonstrated that neem oil microemulsion was effective against Sarcoptes scabie var. cuniculi larvae in vitro. PMID:20304561

  18. Action of neem oil (Azadirachta indica A. Juss) on cocoon spinning in Ceraeochrysa claveri (Neuroptera: Chrysopidae).

    PubMed

    Scudeler, Elton Luiz; Garcia, Ana Silvia Gimenes; Padovani, Carlos Roberto; Santos, Daniela Carvalho

    2013-11-01

    Neem oil is a biopesticide that disturbs the endocrine and neuroendocrine systems of pests and may interfere with molting, metamorphosis and cocoon spinning. The cocoon serves protective functions for the pupa during metamorphosis, and these functions are dependent on cocoon structure. To assess the changes in cocoon spinning caused by neem oil ingestion, Ceraeochrysa claveri larvae, a common polyphagous predator, were fed with neem oil throughout the larval period. When treated with neem oil, changes were observed on the outer and inner surfaces of the C. claveri cocoon, such as decreased wall thickness and impaired ability to attach to a substrate. These negative effects may reduce the effectiveness of the mechanical and protective functions of cocoons during pupation, which makes the specimen more vulnerable to natural enemies and environmental factors.

  19. Action of neem oil (Azadirachta indica A. Juss) on cocoon spinning in Ceraeochrysa claveri (Neuroptera: Chrysopidae).

    PubMed

    Scudeler, Elton Luiz; Garcia, Ana Silvia Gimenes; Padovani, Carlos Roberto; Santos, Daniela Carvalho

    2013-11-01

    Neem oil is a biopesticide that disturbs the endocrine and neuroendocrine systems of pests and may interfere with molting, metamorphosis and cocoon spinning. The cocoon serves protective functions for the pupa during metamorphosis, and these functions are dependent on cocoon structure. To assess the changes in cocoon spinning caused by neem oil ingestion, Ceraeochrysa claveri larvae, a common polyphagous predator, were fed with neem oil throughout the larval period. When treated with neem oil, changes were observed on the outer and inner surfaces of the C. claveri cocoon, such as decreased wall thickness and impaired ability to attach to a substrate. These negative effects may reduce the effectiveness of the mechanical and protective functions of cocoons during pupation, which makes the specimen more vulnerable to natural enemies and environmental factors. PMID:23993219

  20. Neem leaves as a source of fertilizer-cum-pesticide vermicompost.

    PubMed

    Gajalakshmi, S; Abbasi, S A

    2004-05-01

    Vermicomposting of neem (Azadirachta indica A. Juss) was accomplished in "high-rate" reactors operated at the earthworm (Eudrilus eugeniae) densities of 62.5 and 75 animals per litre of reactor volume. Contrary to the fears that neem--a powerful nematicide--might not be palatable to the annelids, the earthworms fed voraciously on the neem compost, converting upto 7% of the feed into vermicompost per day. Indeed the worms grew faster and reproduced more rapidly in the neem-fed vermireactors than in the reactors fed with mango leaf litter earlier studied by the authors (Gajalakshmi et al., 2003). Another set of experiments on the growth, flowering, and fruition of brinjal (Solanum melongena) plants with and without fertilization with vermicompost, revealed that the vermicompost had a significantly beneficial impact.

  1. Effect of neem (Azardirachta indica A. Juss) seeds and leaves extract on some plant pathogenic fungi.

    PubMed

    Moslem, M A; El-Kholie, E M

    2009-07-15

    In this study plant pathogenic fungi Alternaria solani, Fusarium oxysporum, Rhizoctonia solani and Sclerotinia sclerotiorum were chosen to study the effect of ethanolic, hexane and methanolic extracts of neem seeds and leaves. Antifungal effects of neem leave and seed extracts obtained by ethanol, hexane and ptrolium ether were examined separately in vitro against Fusarium oxysporum, Rhizoctonia solani, Alternaria solani and Sclerotinia sclerotiorum. Results indicated that seeds and leaves extracts could cause growth inhibition of tested fungi, although the rate of inhibition of tested fungi varied with different extracts and concentrations. But all these extracts and concentrations of extract inhibited the growth of pathogenic fungi at a significant level. Azadirachtin, nimonol and expoxyazdirodione were detected from neem extract by using High Performance Liquid Chromatography (HPLC). We can conclude that neem leave and seed extracts were effective as antifungal against all tested fungi but F. oxysporum and R. solani were the most sensitive fungi. PMID:19947185

  2. Synergistic effect of entomogenous fungi on some insecticides against Bihar hairy caterpillar Spilarctia obliqua (Lepidoptera: Arctiidae).

    PubMed

    Purwar, J P; Sachan, G C

    2006-01-01

    A number of fungal parasites infect a wide range of insects and cause epizootics from time to time. Beauveria bassiana (Balsamo) Vuillemin and Metarhizium anisopliae (Metschnikoff) Sorokin are two of the major disease-causing fungi in insects. Investigations were carried out to study the effect of these fungi on the toxicity of endosulfan, imidacloprid, lufenuron, diflubenzuron, dimethoate and oxydemeton methyl against 10-11 days old larvae of Spilarctia obliqua (Walker). For some products the combination treatments showed higher dose mortality response than the sole treatment of fungal conidia or the insecticide. The combination of insecticides with B. bassiana showed 1.26-35.8 fold increase in toxicity of insecticides over sole treatment, while the increase was 1.05-72.0 fold in case of M. anisopliae. Imidacloprid 17.8 SL and oxydemeton methyl 25EC may be used in combination with these fungi for management of S. obliqua. PMID:16338588

  3. Insecticides and the Great Lakes

    USGS Publications Warehouse

    Reinert, Robert E.

    1969-01-01

    Cracks in the perfect image of DDT appeared when traces of the insecticide began to show up in a wide variety of organisms throughout the world. As more and more people investigated this problem, it became increasingly evident that terrestrial and aquatic animals were accumulating comparatively high concentrations of DDT from extremely low levels in their environment. It also became apparent that DDT and all of the other chlorinated hydrocarbon insecticides were not species-specific, but were toxic to all forms of animal life including man. In 1965, when the Great Lakes Fishery Laboratory of the U.S. Bureau of Commercial Fisheries began to monitor pesticide residues in fish from the Great Lakes, it was discovered that the fish contained not only DDT, but also dieldrin, another chlorinated hydrocarbon insecticide. Fish from Lake Michigan in particular contained relatively high levels of both of these insecticides; concentrations of DDT were in the parts per million (ppm) range, a factor at least several million times greater than the few parts per trillion found in the water. Two questions presented themselves: first, How did these insecticides get into the water? and second, How did the fish build up such high concentrations in their bodies from such low concentrations in the water?

  4. Ultra structural study of the rat cheek epithelium treated with Neem extract.

    PubMed

    Azmi, Muhammad Arshad; Khatoon, Nasira; Ghaffar, Rizwana Abdul

    2015-11-01

    The purpose of this study was to investigate the effects of neem extract (Azadirachta indica A. Juss) on the ultrastructure of the rat oral epithelium, because neem extract has been added in the tooth paste as an anti-plaque-forming substance in Asian countries. The non-toxic dose of 2000 mg/kg body weight of Neem extract (NBE) was applied daily to the surface of buccal epithelium for four weeks and controls did not receive Neem extract. After four weeks cheek epithelial tissues were excised and processed for light microscopy, scanning and transmission electron microscopy. Light microscopy did not show significant differences between NBE-treated and control epithelium. Difference between control and treated rats weight was non-significant. Moreover, time period was also non-significant. Irregular cell surfaces were noticed when compared to control specimens when examined by scanning electron microscopy. Under transmission electron microscopy, wider intercellular spaces were observed in the treated epithelial spinous cellular layers when compared to control. Further, more keratohyalin granules were present in experimental granular cells. It was concluded that present study showed differences between Neem-treated and control in epithelial tissues but these structural differences may not be related to adverse side effects of the Neem extract.

  5. A 90-day subchronic toxicity study of neem oil, a Azadirachta indica oil, in mice.

    PubMed

    Wang, C; Cao, M; Shi, D-X; Yin, Z-Q; Jia, R-Y; Wang, K-Y; Geng, Y; Wang, Y; Yao, X-P; Yang, Z-R; Zhao, J

    2013-09-01

    To determine the no-observed-adverse-effect level (NOAEL) of exposure and target organs of neem oil for establishing safety criteria for human exposure, the subchronic toxicity study with neem oil in mice was evaluated. The mice (10 per sex for each dose) was orally administered with neem oil with the doses of 0 (to serve as a control), 177, 533 and 1600 mg/kg/day for 90 days. After the treatment period, observation of reversibility or persistence of any toxic effects, mice were continuously fed without treatment for the following 30 days. During the two test periods, the serum biochemistry, organ weight and histopathology were examined. The results showed that the serum biochemistry and organ coefficient in experimental groups had no statistical difference compared with those of the control group. At the 90th day, the histopathological examinations showed that the 1600 mg/kg/day dose of neem oil had varying degrees of damage on each organ except heart, uterus and ovarian. After 30-day recovery, the degree of lesions to the tissues was lessened or even restored. The NOAEL of neem oil was 177 mg/kg/day for mice and the target organs of neem oil were determined to be testicle, liver and kidneys.

  6. Systemic effects of neem on western flower thrips, Frankliniella occidentalis (Thysanoptera: Thripidae).

    PubMed

    Thoeming, G; Borgemeister, C; Sétamou, M; Poehling, H M

    2003-06-01

    The systemic effects of neem on the western flower thrips, Frankliniella occidentalis (Pergande), were investigated in laboratory trials using green bean, Phaseolus vulgaris L., in arena and microcosm experiments. In arena experiments, systemic effects of neem against western flower thrips larvae on primary bean leaves were observed with maximum corrected mortality of 50.6%. In microcosm experiments using bean seedlings, higher efficacy in the control of western flower thrips were observed with soil applications of neem on a substrate mixture (i.e., Fruhstorfer Erde, Type P, and sand) in a 1:1 ratio (93% corrected mortality) compared with application on the commercial substrate only (76% corrected mortality). However, longer persistence of neem was observed with soil application on the commercial substrate, which showed effects against thrips for up to 6 d after application. In addition to systemic effects observed on all foliage-feeding stages of western flower thrips, mortality on contact and repellent effects were observed on soil-inhabiting stages after soil applications of neem. Finally, bean seedlings grown from seeds pregerminated for 3 d in neem emulsion were also toxic to western flower thrips. PMID:12852622

  7. Influence of edaphic factors on the mineralization of neem oil coated urea in four Indian soils.

    PubMed

    Kumar, Rajesh; Devakumar, C; Kumar, Dinesh; Panneerselvam, P; Kakkar, Garima; Arivalagan, T

    2008-11-12

    The utility of neem (Azadirachta indica A Juss) oil coated urea as a value-added nitrogenous fertilizer has been now widely accepted by Indian farmers and the fertilizer industry. In the present study, the expeller grade (EG) and hexane-extracted (HE) neem oils, the two most common commercial grades, were used to prepare neem oil coated urea (NOCU) of various oil doses, for which mineralization rates were assessed in four soils at three incubation temperatures (20, 27, and 35 degrees C). Neem oil dose-dependent conservation of ammonium N was observed in NOCU treatments in all of the soils. However, a longer incubation period and a higher soil temperature caused depletion of ammonium N. Overall, the nitrification in NOCU treatment averaged 56.6% against 77.3% for prilled urea in four soils. NOCU prepared from EG neem oil was consistently superior to that derived from hexane-extracted oil. The performance of NOCUs was best in coarse-textured soil and poorest in sodic soil. The nitrification rate (NR) of the NOCUs in the soils followed the order sodic > fine-textured > medium-textured > coarse-textured. The influence of edaphic factors on NR of NOCUs has been highlighted. The utility of the present study in predicting the performance of NOCU in diverse Indian soils was highlighted through the use of algorithms for computation of the optimum neem oil dose that would cause maximum inhibition of nitrification in any soil. PMID:18841982

  8. A 90-day subchronic toxicity study of neem oil, a Azadirachta indica oil, in mice.

    PubMed

    Wang, C; Cao, M; Shi, D-X; Yin, Z-Q; Jia, R-Y; Wang, K-Y; Geng, Y; Wang, Y; Yao, X-P; Yang, Z-R; Zhao, J

    2013-09-01

    To determine the no-observed-adverse-effect level (NOAEL) of exposure and target organs of neem oil for establishing safety criteria for human exposure, the subchronic toxicity study with neem oil in mice was evaluated. The mice (10 per sex for each dose) was orally administered with neem oil with the doses of 0 (to serve as a control), 177, 533 and 1600 mg/kg/day for 90 days. After the treatment period, observation of reversibility or persistence of any toxic effects, mice were continuously fed without treatment for the following 30 days. During the two test periods, the serum biochemistry, organ weight and histopathology were examined. The results showed that the serum biochemistry and organ coefficient in experimental groups had no statistical difference compared with those of the control group. At the 90th day, the histopathological examinations showed that the 1600 mg/kg/day dose of neem oil had varying degrees of damage on each organ except heart, uterus and ovarian. After 30-day recovery, the degree of lesions to the tissues was lessened or even restored. The NOAEL of neem oil was 177 mg/kg/day for mice and the target organs of neem oil were determined to be testicle, liver and kidneys. PMID:23444337

  9. Influence of edaphic factors on the mineralization of neem oil coated urea in four Indian soils.

    PubMed

    Kumar, Rajesh; Devakumar, C; Kumar, Dinesh; Panneerselvam, P; Kakkar, Garima; Arivalagan, T

    2008-11-12

    The utility of neem (Azadirachta indica A Juss) oil coated urea as a value-added nitrogenous fertilizer has been now widely accepted by Indian farmers and the fertilizer industry. In the present study, the expeller grade (EG) and hexane-extracted (HE) neem oils, the two most common commercial grades, were used to prepare neem oil coated urea (NOCU) of various oil doses, for which mineralization rates were assessed in four soils at three incubation temperatures (20, 27, and 35 degrees C). Neem oil dose-dependent conservation of ammonium N was observed in NOCU treatments in all of the soils. However, a longer incubation period and a higher soil temperature caused depletion of ammonium N. Overall, the nitrification in NOCU treatment averaged 56.6% against 77.3% for prilled urea in four soils. NOCU prepared from EG neem oil was consistently superior to that derived from hexane-extracted oil. The performance of NOCUs was best in coarse-textured soil and poorest in sodic soil. The nitrification rate (NR) of the NOCUs in the soils followed the order sodic > fine-textured > medium-textured > coarse-textured. The influence of edaphic factors on NR of NOCUs has been highlighted. The utility of the present study in predicting the performance of NOCU in diverse Indian soils was highlighted through the use of algorithms for computation of the optimum neem oil dose that would cause maximum inhibition of nitrification in any soil.

  10. Laboratory Evaluation of Toxicity of Insecticide Formulations from Different Classes against American Cockroach (Dictyoptera: Blattidae)

    PubMed Central

    Syed, Ruhma; Manzoor, Farkhanda; Adalat, Rooma; Abdul-Sattar, Abida; Syed, Azka

    2014-01-01

    Background The present study was designed to investigate the insecticidal efficacy of four different classes of insecticides: pyrethroids, organophosphates, phenyl-pyrazoles and neo-nicotenoids. One representative chemical from each class was selected to compare the toxicity: deltamethrin from pyrethroids, Dichlorovinyl Dimethyl Phosphate (DDVP) from organophosphates, fipronil from phenyl-pyrazoles and imidacloprid from neo-nicotenoids. The objective of this study was to determine which of these insecticides were most effective against American cockroach. Methods: These insecticides were tested for their LC50 values against Periplaneta americana under topical bioassay method, using different concentrations for each chemical. Results: Fipronil 2.5% EC was highly effective at all concentrations applied, while DDVP 50% EC was least toxic amongst all. One way analysis of variance confirmed significant differences between mortality of P. americana and different concentrations applied (P< 0.05). Conclusion: Locality differentiation is an important factor in determining the range of resistance between various localities, as all three localities behaved differently in terms of their levels of resistance. PMID:25629062

  11. Azadirachtin, a neem biopesticide: subchronic toxicity assessment in rats.

    PubMed

    Raizada, R B; Srivastava, M K; Kaushal, R A; Singh, R P

    2001-05-01

    Azadirachtin, a biopesticide obtained from neem, was subjected to subchronic toxicological testing to document its safety for use as a pesticide. Azadirachtin technical 12% orally administered to male and female rats at doses of 500, 1000 and 1500 mg/kg/day for 90 days did not produce any signs of toxicity, mortality, changes in tissue weight, pathology and serum and blood parameters. It can be suggested that azadirachtin at the highest dose tested is well tolerated by rats of both sexes. The highest dose, 1500 mg/kg, can be used as a basal dose for the determination of the no-observed-effect level (NOEL) of azadirachtin to calculate its safety margin. PMID:11313114

  12. Neem Oil and Crop Protection: From Now to the Future

    PubMed Central

    Campos, Estefânia V. R.; de Oliveira, Jhones L.; Pascoli, Mônica; de Lima, Renata; Fraceto, Leonardo F.

    2016-01-01

    A major challenge of agriculture is to increase food production to meet the needs of the growing world population, without damaging the environment. In current agricultural practices, the control of pests is often accomplished by means of the excessive use of agrochemicals, which can result in environmental pollution and the development of resistant pests. In this context, biopesticides can offer a better alternative to synthetic pesticides, enabling safer control of pest populations. However, limitations of biopesticides, including short shelf life, photosensitivity, and volatilization, make it difficult to use them on a large scale. Here, we review the potential use of neem oil in crop protection, considering the gaps and obstacles associated with the development of sustainable agriculture in the not too distant future. PMID:27790224

  13. Pyrethrum flowers and pyrethroid insecticides.

    PubMed Central

    Casida, J E

    1980-01-01

    The natural pyrethrins from the daisy-like flower, Tanacetum or Chrysanthemum cinerariifolium, are nonpersistent insecticides of low toxicity to mammals. Synthetic analogs or pyrethroids, evolved from the natural compounds by successive isosteric modifications, are more potent and stable and are the newest important class of crop protection chemicals. They retain many of the favorable properties of the pyrethrins. PMID:6993201

  14. Bioassays for Monitoring Insecticide Resistance

    PubMed Central

    Miller, Audra L.E.; Tindall, Kelly; Leonard, B. Rogers

    2010-01-01

    Pest resistance to pesticides is an increasing problem because pesticides are an integral part of high-yielding production agriculture. When few products are labeled for an individual pest within a particular crop system, chemical control options are limited. Therefore, the same product(s) are used repeatedly and continual selection pressure is placed on the target pest. There are both financial and environmental costs associated with the development of resistant populations. The cost of pesticide resistance has been estimated at approximately $ 1.5 billion annually in the United States. This paper will describe protocols, currently used to monitor arthropod (specifically insects) populations for the development of resistance. The adult vial test is used to measure the toxicity to contact insecticides and a modification of this test is used for plant-systemic insecticides. In these bioassays, insects are exposed to technical grade insecticide and responses (mortality) recorded at a specific post-exposure interval. The mortality data are subjected to Log Dose probit analysis to generate estimates of a lethal concentration that provides mortality to 50% (LC50) of the target populations and a series of confidence limits (CL's) as estimates of data variability. When these data are collected for a range of insecticide-susceptible populations, the LC50 can be used as baseline data for future monitoring purposes. After populations have been exposed to products, the results can be compared to a previously determined LC50 using the same methodology. PMID:21248689

  15. Limonene--A Natural Insecticide.

    ERIC Educational Resources Information Center

    Beatty, Joseph H.

    1986-01-01

    Describes a high school chemistry student's research project in which limonene was isolated from the oil of lemons and oranges. Outlines the students' tests on the use of this chemical as an insecticide. Discusses possible extensions of the exercises based on questions generated by the students. (TW)

  16. Toxicity of the insecticide fipronil and its degradates to benthic macroinvertebrates of urban streams.

    PubMed

    Weston, Donald P; Lydy, Michael J

    2014-01-21

    Fipronil is a phenylpyrazole insecticide with increasing urban use. Sixteen urban waterways and municipal wastewater were sampled for fipronil, its environmental degradates, and pyrethroid insecticides. Because findings could not be interpreted with existing data on fipronil degradate toxicity, EC50s and LC50s for fipronil and its sulfide and sulfone derivatives were determined for 14 macroinvertebrate species. Four species were more sensitive than any previously studied, indicating fipronil's toxicity to aquatic life has long been underestimated. The most sensitive species tested, Chironomus dilutus, had a mean 96-h EC50 of 32.5 ng/L for fipronil and 7-10 ng/L for its degradates. Hyalella azteca, a common testing species, was among the least sensitive. The typical northern California creek receiving urban stormwater runoff contains fipronil and degradate concentrations twice the EC50 of C. dilutus, and approximately one-third the EC50 for a stonefly, a caddisfly, and two mayfly species. The present study substantially increases data available on toxicity of fipronil degradates, and demonstrates that fipronil and degradates are common in urban waterways at concentrations posing a risk to a wide variety of stream invertebrates.

  17. Canada files WTO complaint against EC.

    PubMed

    2000-01-01

    In December 1998, Canada filed a complaint alleging that the European Communities (EC) had adopted regulations that amounted to a scheme to extend patent terms, limited to pharmaceutical and agricultural chemical products.

  18. Ecdysteroid receptor from the American lobster Homarus americanus: EcR/RXR isoform cloning and ligand-binding properties.

    PubMed

    Tarrant, Ann M; Behrendt, Lars; Stegeman, John J; Verslycke, Tim

    2011-09-01

    In arthropods, ecdysteroids regulate molting by activating a heterodimer formed by the ecdysone receptor (EcR) and retinoid X receptor (RXR). While this mechanism is similar in insects and crustaceans, variation in receptor splicing, dimerization and ligand affinity adds specificity to molting processes. This study reports the EcR and RXR sequences from American lobster, a commercially and ecologically important crustacean. We cloned two EcR splice variants, both of which specifically bind ponasterone A, and two RXR variants, both of which enhance binding of ponasterone A to the EcR. Lobster EcR has high affinity for ponasterone A and muristerone and moderately high affinity for the insecticide tebufenozide. Bisphenol A, diethyl phthalate, and two polychlorinated biphenyls (PCB 29 and PCB 30), environmental chemicals shown to interfere with crustacean molting, showed little or no affinity for lobster EcR. These studies establish the molecular basis for investigation of lobster ecdysteroid signaling and signal disruption by environmental chemicals.

  19. Evaluation of anti-plaque microbial activity of Azadirachta indica (neem oil) in vitro: A pilot study

    PubMed Central

    Elavarasu, Sugumari; Abinaya, P.; Elanchezhiyan, S.; Thangakumaran; Vennila, K.; Naziya, K. B.

    2012-01-01

    Background: Probably microbial plaque is the main etiology for periodontal tissue inflammation. Various chemical agents have been evaluated over the years with respect to their antimicrobial effects in the oral cavity. However, all are associated with side effects that prohibit regular long-term use. Therefore, the effectiveness of Azadirachta indica (neem) against plaque formation is considered to be vital, with lesser side effects. The aim of the present study is to evaluate and prove the antimicrobial activity of neem using plaque samples. Materials and Methods: Culture was prepared using brain heart infusion broth reagent. Dental plaque samples were used for that. Kirby–Bauer antimicrobial susceptibility test procedure was carried away with the sample. Neem oil was kept in the agar plate with culture and the diameter of inhibition zones was calculated. Results: Results showed inhibition zones on the agar plate around neem oil. Conclusion: Study shows definite antiplaque activity of neem oil. PMID:23066297

  20. Pyridalyl, a novel insecticide: potency and insecticidal selectivity.

    PubMed

    Isayama, S; Saito, S; Kuroda, K; Umeda, K; Kasamatsu, K

    2005-04-01

    Pyridalyl is an insecticide of a novel chemical class (unclassified insecticides). Toxicity of pyridalyl to two insect pest species, Spodoptera litura and Frankliniella occidentalis, an insect predator, Orius stringicollis, and a pollinator, Bombus terrestris, was evaluated in the laboratory. The insecticidal activity of pyridalyl against S. litura was evaluated using the leaf-dipping method. The potency of pyridalyl was highly effective against all development stages (2nd to 6th instar larvae) of S. litura. This compound was also evaluated against F. occidentalis using the direct spray method. For F. occidentalis, toxicity of pyridalyl was almost similar to that of acrinathrin, but greater than acrinathrin for adults. Then the toxicity of this product to the natural enemies, Orius stringicollis and the pollinating insect Bombus terrestris, was evaluated using the body-dipping method or direct spray method. No acute toxicity of this product was observed on these non-target insects. Moreover, the influence of pyridalyl to the nest of Bombus terrestris was evaluated using the direct spray to the inside of the nest. No apparent influence of this compound was observed by 21 days after treatment. The cytotoxicity of pyridalyl to the Sf9 insect cell line and the CHO-K1 mammalian cell line was evaluated using the trypan-blue exclusion method. High toxicity to the insect cell line, but almost no toxicity to the mammalian cell line, was observed. Thus, pyridalyl exhibited high selectivity in cytotoxicity between the insect and mammalian cell line as well as in insecticidal activity among insect species. We infer pyridalyl may be useful for IPM programs of greenhouse cultivation system. PMID:15756699

  1. Toxicity and bioefficacy of individual and combination of diversified insecticides against jute hairy caterpillar, Spilarctia obliqua.

    PubMed

    Selvaraj, K; Ramesh, V; Gotyal, B S; Satpathy, S

    2015-11-01

    Toxicity of conventional (profenofos 50 EC and λ-cyhalothrin 5 EC) and non-conventional (flubendiamide 480 SC, chlorantraniliprole 18.5 SC, emamectin benzoate 5 SG) insecticides was determined on the basis of median lethal concentration (LC50) values on third instar larvae of jute hairy caterpillar, Spilarctia obliqua under laboratory conditions. Further, the promising binary insecticides combinations with lesser LC50 values and adequate synergistic activity were evaluated under field conditions. The LC50 values calculated for insecticides viz., chlorantraniliprole, flubendiamide emamectin benzoate, λ-cyhalothrin and profenophos were 0.212, 0.232, 0.511, 0.985 and 3.263 ppm, respectively. Likewise, the LC50 values for flubendiamide with λ-cyhalothrin in 3:1 proportion was most toxic (0.103 ppm) amongst all the other binary combinations with λ-cyhalothrin. Chlorantraniliprole in combination with λ-cyhalothrin at 1:1 proportion (0.209 ppm) was most toxic followed by 3:1 proportion (0.345 ppm). Similarly, emamectin benzoate in combination with λ-cyhalothrin at 1:1 proportion was more toxic (0.271 ppm) than 3:1 ratio (0.333 ppm). Toxicity index of flubendiamide + λ-cyhalothrin (3:1 ratio) was highest (970.87). Bioefficacy of synergistic binary combinations along with individual insecticides established the superiority of profenophos + λ-cyhalothrin (3:1) with 89.12% reduction in infestation and recorded maximum fibre yield 38.67qha' under field condition. Moreover, combination of diverse insecticides group might sustain toxicity against the target insect for longer period with least probability of resistance development. PMID:26688981

  2. Toxicity and bioefficacy of individual and combination of diversified insecticides against jute hairy caterpillar, Spilarctia obliqua.

    PubMed

    Selvaraj, K; Ramesh, V; Gotyal, B S; Satpathy, S

    2015-11-01

    Toxicity of conventional (profenofos 50 EC and λ-cyhalothrin 5 EC) and non-conventional (flubendiamide 480 SC, chlorantraniliprole 18.5 SC, emamectin benzoate 5 SG) insecticides was determined on the basis of median lethal concentration (LC50) values on third instar larvae of jute hairy caterpillar, Spilarctia obliqua under laboratory conditions. Further, the promising binary insecticides combinations with lesser LC50 values and adequate synergistic activity were evaluated under field conditions. The LC50 values calculated for insecticides viz., chlorantraniliprole, flubendiamide emamectin benzoate, λ-cyhalothrin and profenophos were 0.212, 0.232, 0.511, 0.985 and 3.263 ppm, respectively. Likewise, the LC50 values for flubendiamide with λ-cyhalothrin in 3:1 proportion was most toxic (0.103 ppm) amongst all the other binary combinations with λ-cyhalothrin. Chlorantraniliprole in combination with λ-cyhalothrin at 1:1 proportion (0.209 ppm) was most toxic followed by 3:1 proportion (0.345 ppm). Similarly, emamectin benzoate in combination with λ-cyhalothrin at 1:1 proportion was more toxic (0.271 ppm) than 3:1 ratio (0.333 ppm). Toxicity index of flubendiamide + λ-cyhalothrin (3:1 ratio) was highest (970.87). Bioefficacy of synergistic binary combinations along with individual insecticides established the superiority of profenophos + λ-cyhalothrin (3:1) with 89.12% reduction in infestation and recorded maximum fibre yield 38.67qha' under field condition. Moreover, combination of diverse insecticides group might sustain toxicity against the target insect for longer period with least probability of resistance development.

  3. Screening and design of anti-diabetic compounds sourced from the leaves of neem (Azadirachta indica).

    PubMed

    Jalil, Asma; Ashfaq, Usman Ali; Shahzadi, Samar; Rasul, Ijaz; Rehman, Shahid-Ur; Shah, Masaud; Javed, Muhammad Rizwan; Masoud, Muhammad Shareef

    2013-01-01

    Diabetes Mellitus is affecting people of all age groups worldwide. Many synthetic medicines available for type 2 diabetes mellitus in the market. However, there is a strong requirement for the development of better anti-diabetes compounds sourced especially from natural sources like medicinal plants. The extracts from the leaves of neem (Azadirachta indica) is traditionally known to have anti-diabetes properties. Therefore, there is an increased interest to identify potential compounds identified from neem leaf extracts showing predicted binding property with the known diabetes mellitus type 2 protein enzyme target phosphoenol-pyruvate carboxykinase(PEPCK). The structure data for compounds found in the leaf extract of neem was screened against PEPCK using molecular docking simulation and screening techniques. Results show that the compound 3-Deacetyl-3-cinnamoyl-azadirachtin possesses best binding properties with PEPCK. This observation finds application for further consideration in in vitro and in vivo validation. PMID:24497731

  4. Therapeutics Role of Azadirachta indica (Neem) and Their Active Constituents in Diseases Prevention and Treatment.

    PubMed

    Alzohairy, Mohammad A

    2016-01-01

    Neem (Azadirachta indica) is a member of the Meliaceae family and its role as health-promoting effect is attributed because it is rich source of antioxidant. It has been widely used in Chinese, Ayurvedic, and Unani medicines worldwide especially in Indian Subcontinent in the treatment and prevention of various diseases. Earlier finding confirmed that neem and its constituents play role in the scavenging of free radical generation and prevention of disease pathogenesis. The studies based on animal model established that neem and its chief constituents play pivotal role in anticancer management through the modulation of various molecular pathways including p53, pTEN, NF-κB, PI3K/Akt, Bcl-2, and VEGF. It is considered as safe medicinal plants and modulates the numerous biological processes without any adverse effect. In this review, I summarize the role of Azadirachta indica in the prevention and treatment of diseases via the regulation of various biological and physiological pathways.

  5. Repellency of the oily extract of neem seeds (Azadirachta indica) against Varroa destructor (Acari: Varroidae).

    PubMed

    González-Gómez, Rebeca; Otero-Colina, Gabriel; Villanueva-Jiménez, Juan A; Peña-Valdivia, Cecilia Beatriz; Santizo-Rincón, José Antonio

    2012-03-01

    A crude oil extract of neem seed (Azadirachta indica, Sapindales: Meliaceae) was evaluated for repellency on Varroa destructor Anderson and Trueman. Burgerjon's tower was used to spray worker bee pupae with 0.0, 0.3, 0.7, 1.3, 2.6, 5.3, 10.6 and 21.1% neem extract concentrations. Sprayed pupae were attached to observation arenas and incubated at 32 ± 2°C and 70 ± 10% RH. The ability of V. destructor to locate and feed on treated and untreated pupae was monitored from 30 min to 72 h after spray. Higher and more stable repellency was achieved with 2.6, 5.3, 10.6 and 21.1% neem extract. At the highest concentration, 98% of V. destructor were prevented to settle on bee pupae, resulting in 100% V. destructor mortality at 72 h.

  6. Toxicity of Neem's oil, a potential biocide against the invasive mussel Limnoperna fortunei (Dunker 1857).

    PubMed

    Pereyra, Patricio J; Rossini, Gustavo B; Darrigran, Gustavo

    2012-12-01

    The golden mussel Limnoperna fortunei (Dunker 1857) is one of the most distributed Nuisance Invasive Species (NIS) in South America, and a threat of great concern for the industry of the area. In this study, we carried out toxicity tests made with a Neem's oil solution with L. fortunei larvae and benthonic adults (7, 13 and 19 ± 1 mm). Tests with non-target species (Daphnia magna, Lactuca sativa and Cnesterodon decemmculatus) were also made with the aim to evaluate the potential toxicity of the Neem's solution in the environment. The LC(100) of Neem's solution obtained for larvae was 500 µl/L, a value much higher than the one obtained for D. magna and C. decemmaculatus. Thus, we recommend that it should not be used in open waters. However, since the adults were killed in 72 h and the larvae in 24 h, this product can be used in closed systems, in man-made facilities. PMID:22990602

  7. Repellency of the oily extract of neem seeds (Azadirachta indica) against Varroa destructor (Acari: Varroidae).

    PubMed

    González-Gómez, Rebeca; Otero-Colina, Gabriel; Villanueva-Jiménez, Juan A; Peña-Valdivia, Cecilia Beatriz; Santizo-Rincón, José Antonio

    2012-03-01

    A crude oil extract of neem seed (Azadirachta indica, Sapindales: Meliaceae) was evaluated for repellency on Varroa destructor Anderson and Trueman. Burgerjon's tower was used to spray worker bee pupae with 0.0, 0.3, 0.7, 1.3, 2.6, 5.3, 10.6 and 21.1% neem extract concentrations. Sprayed pupae were attached to observation arenas and incubated at 32 ± 2°C and 70 ± 10% RH. The ability of V. destructor to locate and feed on treated and untreated pupae was monitored from 30 min to 72 h after spray. Higher and more stable repellency was achieved with 2.6, 5.3, 10.6 and 21.1% neem extract. At the highest concentration, 98% of V. destructor were prevented to settle on bee pupae, resulting in 100% V. destructor mortality at 72 h. PMID:22270115

  8. Therapeutics Role of Azadirachta indica (Neem) and Their Active Constituents in Diseases Prevention and Treatment

    PubMed Central

    Alzohairy, Mohammad A.

    2016-01-01

    Neem (Azadirachta indica) is a member of the Meliaceae family and its role as health-promoting effect is attributed because it is rich source of antioxidant. It has been widely used in Chinese, Ayurvedic, and Unani medicines worldwide especially in Indian Subcontinent in the treatment and prevention of various diseases. Earlier finding confirmed that neem and its constituents play role in the scavenging of free radical generation and prevention of disease pathogenesis. The studies based on animal model established that neem and its chief constituents play pivotal role in anticancer management through the modulation of various molecular pathways including p53, pTEN, NF-κB, PI3K/Akt, Bcl-2, and VEGF. It is considered as safe medicinal plants and modulates the numerous biological processes without any adverse effect. In this review, I summarize the role of Azadirachta indica in the prevention and treatment of diseases via the regulation of various biological and physiological pathways. PMID:27034694

  9. Molluscicidal effects of neem (Azadirachta indica) extracts on edible tropical land snails.

    PubMed

    Ebenso, Ime E

    2004-02-01

    The effects of 350, 500 and 700 mg kg(-1) of crude extracts of neem, Azadirachta indica A Juss, on edible tropical land snails Archachatina marginata and Limicolaria aurora (Jay) were determined and compared with control using pawpaw, Carica papaya L as bait. Responses were measured through normal feeding, cessation of food intake, cessation of crawling, mucus secretion, lack of response to mechanical stimuli (mortality) and decomposition. Results showed no effects on the controls or snails exposed to neem seed oil extract. Crude extracts of bark, root and leaf of neem at 500 and 700 mg kg(-1) produced mortality after exposure for 48 h for L aurora and 72 h for A marginata. PMID:14971686

  10. The insecticide-resistance problem

    PubMed Central

    Brown, A. W. A.

    1958-01-01

    The author reviews the growth of the insecticide-resistance problem throughout the world during the period between July 1956 and November 1957, and the developments in research on the subject during the same period. Three new resistant species have been discovered—Anopheles subpictus, Chrysomyia putoria and Rhipicephalus sanguineus—and eight new types of resistance in already resistant species have been observed. Moreover, the geographical area covered by certain resistant insect populations has considerably increased. The research accomplishments during the period under review include: systems of detecting resistance in the field by standard test methods; confirmation of two distinct types of resistance to chlorinated-hydrocarbon insecticides in mosquitos and bed-bugs as well as in houseflies; evidence that DDT-resistance in the housefly, Anopheles sundaicus and Aëdes aegypti is due mainly to a single genetic factor associated with the ability to dehydrochlorinate DDT, and that dieldrin-resistance of Anopheles gambiae also derives from a single factor present even in untouched populations; a fuller understanding of the physiological mechanism of BHC-resistance in the housefly; and demonstration that selection pressure from organo-phosphorus compounds induces resistance to themselves and to chlorinated-hydrocarbon insecticides. PMID:13536795

  11. Insecticidal and fungicidal activity of new synthesized chitosan derivatives.

    PubMed

    Rabea, Entsar I; Badawy, Mohamed E I; Rogge, Tina M; Stevens, Christian V; Höfte, Monica; Steurbaut, Walter; Smagghe, Guy

    2005-10-01

    Chitosan, the N-deacetylated derivative of chitin, is a potential biopolysaccharide owing to its specific structure and properties. In this paper, we report on the synthesis of 24 new chitosan derivatives, N-alkyl chitosans (NAC) and N-benzyl chitosans (NBC), that are soluble in dilute aqueous acetic acid. The different derivatives were synthesized by reductive amination and analyzed by 1H NMR spectroscopy. A high degree of substitution (DS) was obtained with N-(butyl)chitosan (DS 0.36) at a 1:1 mole ratio for NAC derivatives and N-(2,4-dichlorobenzyl)chitosan (DS 0.52) for NBC derivatives. Their insecticidal and fungicidal activities were tested against larvae of the cotton leafworm Spodoptera littoralis (Boisduval) (Lepidoptera: Noctuidae), the grey mould Botrytis cinerea Pers (Leotiales: Sclerotiniaceae) and the rice leaf blast Pyricularia grisea Cavara (Teleomorph: Magnaporthe grisea (Hebert) Barr). The oral feeding bioassay indicated that all the derivatives had significant insecticidal activity at 5 g kg(-1) in artificial diet. The most active was N-(2-chloro-6-fluorobenzyl)chitosan, which caused 100% mortality at 0.625 g kg(-1), with an estimated LC50 of 0.32 g kg(-1). Treated larvae ceased feeding after 2-3 days; the mechanism of action remains unknown. In a radial hyphal growth bioassay with both plant pathogens, all derivatives showed a higher fungicidal action than chitosan. N-Dodecylchitosan, N-(p-isopropylbenzyl)chitosan and N-(2,6-dichlorobenzyl)chitosan were the most active against B cinerea, with EC50 values of 0.57, 0.57 and 0.52 g litre(-1), respectively. Against P grisea, N-(m-nitrobenzyl)chitosan was the most active, with 77% inhibition at 5 g litre(-1). The effect of different substitutions is discussed in relation to insecticidal and fungicidal activity.

  12. Cytotoxic effects of neem oil in the midgut of the predator Ceraeochrysa claveri.

    PubMed

    Scudeler, Elton Luiz; Garcia, Ana Silvia Gimenes; Padovani, Carlos Roberto; Pinheiro, Patricia Fernanda Felipe; dos Santos, Daniela Carvalho

    2016-01-01

    Studies of morphological and ultrastructural alterations in target organs have been useful for evaluating the sublethal effects of biopesticides regarded as safe for non-target organisms in ecotoxicological analyses. One of the most widely used biopesticides is neem oil, and its safety and compatibility with natural enemies have been further clarified through bioassays performed to analyze the effects of indirect exposure by the intake of poisoned prey. Thus, this study examined the cellular response of midgut epithelial cells of the adult lacewing, Ceraeochrysa claveri, to neem oil exposure via intake of neem oil-contaminated prey during the larval stage. C. claveri larvae were fed Diatraea saccharalis eggs treated with neem oil at concentrations of 0.5%, 1% and 2% throughout the larval stage. The adult females obtained from these treatments were used at two ages (newly emerged and at the start of oviposition) in morphological and ultrastructural analyses. Neem oil was found to cause pronounced cytotoxic effects in the adult midgut, such as cell dilation, emission of cytoplasmic protrusions, cell lysis, loss of integrity of the cell cortex, dilation of cisternae of the rough endoplasmic reticulum, swollen mitochondria, vesiculated appearance of the Golgi complex and dilated invaginations of the basal labyrinth. Epithelial cells responded to those injuries with various cytoprotective and detoxification mechanisms, including increases in cell proliferation, the number of calcium-containing cytoplasmic granules, and HSP 70 expression, autophagic processes and the development of smooth endoplasmic reticulum, but these mechanisms were insufficient for recovery from all of the cellular damage to the midgut. This study demonstrates that neem oil exposure impairs the midgut by causing sublethal effects that may affect the physiological functions of this organ, indicating the importance of studies of different life stages of this species and similar species to evaluate the

  13. Cytotoxic effects of neem oil in the midgut of the predator Ceraeochrysa claveri.

    PubMed

    Scudeler, Elton Luiz; Garcia, Ana Silvia Gimenes; Padovani, Carlos Roberto; Pinheiro, Patricia Fernanda Felipe; dos Santos, Daniela Carvalho

    2016-01-01

    Studies of morphological and ultrastructural alterations in target organs have been useful for evaluating the sublethal effects of biopesticides regarded as safe for non-target organisms in ecotoxicological analyses. One of the most widely used biopesticides is neem oil, and its safety and compatibility with natural enemies have been further clarified through bioassays performed to analyze the effects of indirect exposure by the intake of poisoned prey. Thus, this study examined the cellular response of midgut epithelial cells of the adult lacewing, Ceraeochrysa claveri, to neem oil exposure via intake of neem oil-contaminated prey during the larval stage. C. claveri larvae were fed Diatraea saccharalis eggs treated with neem oil at concentrations of 0.5%, 1% and 2% throughout the larval stage. The adult females obtained from these treatments were used at two ages (newly emerged and at the start of oviposition) in morphological and ultrastructural analyses. Neem oil was found to cause pronounced cytotoxic effects in the adult midgut, such as cell dilation, emission of cytoplasmic protrusions, cell lysis, loss of integrity of the cell cortex, dilation of cisternae of the rough endoplasmic reticulum, swollen mitochondria, vesiculated appearance of the Golgi complex and dilated invaginations of the basal labyrinth. Epithelial cells responded to those injuries with various cytoprotective and detoxification mechanisms, including increases in cell proliferation, the number of calcium-containing cytoplasmic granules, and HSP 70 expression, autophagic processes and the development of smooth endoplasmic reticulum, but these mechanisms were insufficient for recovery from all of the cellular damage to the midgut. This study demonstrates that neem oil exposure impairs the midgut by causing sublethal effects that may affect the physiological functions of this organ, indicating the importance of studies of different life stages of this species and similar species to evaluate the

  14. Influence of physicochemical parameters of neem (Azadirachta indica A Juss) oils on nitrification inhibition in soil.

    PubMed

    Kumar, Rajesh; Devakumar, C; Sharma, Vandana; Kakkar, Garima; Kumar, Dinesh; Panneerselvam, P

    2007-02-21

    The technology for the production of neem oil coated urea (NOCU) developed by the Indian Agricultural Research Institute is in the pipeline for adaption by several Indian fertilizer industries. Use of nitrification inhibitors is one of the methods of improving the nitrogen use efficiency (NUE) of nitrogenous fertilizers in agriculture. However, standard specifications for the neem oil as a raw material of NOCU are desired. Accordingly, the present study was undertaken to evaluate 25 samples of neem oils comprising 11 samples of expeller grade (EG) oils, 8 samples of cold-pressed (CP) oils, 3 samples of solvent-extracted oils, and 2 commercial formulations. NOCU was prepared using these oils (5000 ppm of urea-N). The soils fertilized with NOCUs (200 ppm of urea-N) were incubated at 27 degrees C and 50% water-holding capacity for a period of 15 days. Nitrapyrin (0.5% of N) coated urea served as the reference and prilled urea as control. Samples were analyzed for NH4+-N, NO2--N, and NO3--N using standard methods. The percent nitrification inhibition (NI) was calculated, and the results revealed that all of the neem oils caused NI ranging from 4.0 to 30.9%. Two samples of EG oils and two commercial formulations were found to be the best, causing 27.0-30.9% NI. Iodine, acid, and saponification values and meliacin content of all of the oils were analyzed and correlated with NI. The results revealed the direct influence of meliacin content of the neem oils on NI, which, however, was found to be negatively correlated with saponification and iodine values. There is, therefore, a need to introduce new Bureau of Indian Standards (BIS) specifications for neem oils as raw materials of NOCU. PMID:17263551

  15. Influence of physicochemical parameters of neem (Azadirachta indica A Juss) oils on nitrification inhibition in soil.

    PubMed

    Kumar, Rajesh; Devakumar, C; Sharma, Vandana; Kakkar, Garima; Kumar, Dinesh; Panneerselvam, P

    2007-02-21

    The technology for the production of neem oil coated urea (NOCU) developed by the Indian Agricultural Research Institute is in the pipeline for adaption by several Indian fertilizer industries. Use of nitrification inhibitors is one of the methods of improving the nitrogen use efficiency (NUE) of nitrogenous fertilizers in agriculture. However, standard specifications for the neem oil as a raw material of NOCU are desired. Accordingly, the present study was undertaken to evaluate 25 samples of neem oils comprising 11 samples of expeller grade (EG) oils, 8 samples of cold-pressed (CP) oils, 3 samples of solvent-extracted oils, and 2 commercial formulations. NOCU was prepared using these oils (5000 ppm of urea-N). The soils fertilized with NOCUs (200 ppm of urea-N) were incubated at 27 degrees C and 50% water-holding capacity for a period of 15 days. Nitrapyrin (0.5% of N) coated urea served as the reference and prilled urea as control. Samples were analyzed for NH4+-N, NO2--N, and NO3--N using standard methods. The percent nitrification inhibition (NI) was calculated, and the results revealed that all of the neem oils caused NI ranging from 4.0 to 30.9%. Two samples of EG oils and two commercial formulations were found to be the best, causing 27.0-30.9% NI. Iodine, acid, and saponification values and meliacin content of all of the oils were analyzed and correlated with NI. The results revealed the direct influence of meliacin content of the neem oils on NI, which, however, was found to be negatively correlated with saponification and iodine values. There is, therefore, a need to introduce new Bureau of Indian Standards (BIS) specifications for neem oils as raw materials of NOCU.

  16. Immunocontraceptive activity guided fractionation and characterization of active constituents of neem (Azadirachta indica) seed extracts.

    PubMed

    Garg, S; Talwar, G P; Upadhyay, S N

    1998-04-01

    A novel approach for immunocontraception by intervention of local cell mediated immunity in the reproductive system by using single intrauterine application of neem oil has been described earlier. The reversible block in fertility was reported to last for 107-180 days in female Wistar rats (Upadhyay et al., 1990. Antifertility effects of neem oil by single intrauterine administration: A novel method of contraception. Proceedings Of The Royal Society Of London B 242, 175-180) and 7-11 months in monkeys (Upadhyay et al., 1994. Long term contraceptive effects of intrauterine neem treatment (IUNT) in bonnet monkeys: An alternative to intrauterine contraceptive devices. Contraception 49, 161-167). The present study, describes the identification and characterization of the biologically active fraction from neem seeds (Azadirachta indica A. Juss. Family Meliaceae), responsible for the above activity in adult female Wistar rats. Initial studies with the mechanically extracted oil and solvent extracts of neem seeds have revealed that the antifertility activity was present in constituents of low to intermediate polarity. A hexane extract of neem seeds was reported to be biologically active (Garg et al., 1994. Comparison of extraction procedures on the immunocontraceptive activity of neem seed extracts. Journal of Ethnopharmacology 22, 87-92). Subsequently, hexane extract was sequentially fractionated through the last active fraction using various separation techniques and tested for antifertility activity at each step. Preparative HPLC was used for isolating individual components of the active fraction in quantities, sufficient for characterization. An analytical HPLC method was developed for standardization of the fraction. The active fraction was identified to be a mixture of six components, which comprises of saturated, mono and di-unsaturated free fatty acids and their methyl esters. Dose response study was performed with the last active fractions. The antifertility

  17. The risk of insecticides to pollinating insects

    PubMed Central

    Connolly, Christopher N.

    2013-01-01

    A key new risk to our pollinators has been identified as exposure to neonicotinoid insecticides. These discoveries have refuelled the debate over whether or not the neonicotinoid insecticides should be banned and conflicting evidence is used in this battle. However, the issue is not black or white, but gray. It is not an issue of whether the neonicotinoids are toxic to insects or not. Clearly, all insecticides were designed and optimized for this attribute. The real question is, or at least should be, which insecticide is the safest for use for a particular need. PMID:24265849

  18. Determination of primary combustion source organic carbon-to-elemental carbon (OC / EC) ratio using ambient OC and EC measurements: secondary OC-EC correlation minimization method

    NASA Astrophysics Data System (ADS)

    Wu, Cheng; Zhen Yu, Jian

    2016-05-01

    Elemental carbon (EC) has been widely used as a tracer to track the portion of co-emitted primary organic carbon (OC) and, by extension, to estimate secondary OC (SOC) from ambient observations of EC and OC. Key to this EC tracer method is to determine an appropriate OC / EC ratio that represents primary combustion emission sources (i.e., (OC / EC)pri) at the observation site. The conventional approaches include regressing OC against EC within a fixed percentile of the lowest (OC / EC) ratio data (usually 5-20 %) or relying on a subset of sampling days with low photochemical activity and dominated by local emissions. The drawback of these approaches is rooted in its empirical nature, i.e., a lack of clear quantitative criteria in the selection of data subsets for the (OC / EC)pri determination. We examine here a method that derives (OC / EC)pri through calculating a hypothetical set of (OC / EC)pri and SOC followed by seeking the minimum of the coefficient of correlation (R2) between SOC and EC. The hypothetical (OC / EC)pri that generates the minimum R2(SOC,EC) then represents the actual (OC / EC)pri ratio if variations of EC and SOC are independent and (OC / EC)pri is relatively constant in the study period. This Minimum R Squared (MRS) method has a clear quantitative criterion for the (OC / EC)pri calculation. This work uses numerically simulated data to evaluate the accuracy of SOC estimation by the MRS method and to compare with two commonly used methods: minimum OC / EC (OC / ECmin) and OC / EC percentile (OC / EC10 %). Log-normally distributed EC and OC concentrations with known proportion of SOC are numerically produced through a pseudorandom number generator. Three scenarios are considered, including a single primary source, two independent primary sources, and two correlated primary sources. The MRS method consistently yields the most accurate SOC estimation. Unbiased SOC estimation by OC / ECmin and OC / EC10 % only occurs when the left tail of

  19. ECS Program Unit Funding: A Handbook of ECS Operators, 2000-2001.

    ERIC Educational Resources Information Center

    Alberta Dept. of Education, Edmonton. Special Education Branch.

    This handbook is written specifically for Early Childhood Services (ECS) operators in Alberta, Canada, applying for Program Unit Funding. It is also designed to enhance the understanding of how assistance is provided to ECS children with severe disabilities by teachers, special needs assistants, parents, and supporting agency personnel. ECS…

  20. ECS Program Unit Funding: A Handbook for ECS Operators. Third Edition.

    ERIC Educational Resources Information Center

    Alberta Dept. of Education, Edmonton. Special Educational Services Branch.

    This handbook is written specifically for Early Childhood Services (ECS) operators in Alberta (Canada) to apply for Program Unit Funding. It is also designed to enhance the understanding of how assistance is provided to ECS children with severe disabilities by teachers, special needs assistants, parents, and supporting agency personnel. ECS…

  1. Morphological alterations in salivary glands of Rhipicephalus sanguineus ticks (Acari: Ixodidae) exposed to neem seed oil with known azadirachtin concentration.

    PubMed

    Remedio, R N; Nunes, P H; Anholeto, L A; Oliveira, P R; Sá, I C G; Camargo-Mathias, M I

    2016-04-01

    Neem (Azadirachta indica) has attracted the attention of researchers worldwide due to its repellent properties and recognized effects on the morphology and physiology of arthropods, including ticks. Therefore, this study aimed to demonstrate the effects of neem seed oil enriched with azadirachtin on salivary glands of Rhipicephalus sanguineus ticks, targets of great veterinary interest because of their ability to transmit pathogens to dogs. For this, R. sanguineus semi-engorged females were subjected to treatment with neem seed oil, with known azadirachtin concentrations (200, 400 and 600ppm). After dissection, salivary glands were collected and evaluated through morphological techniques in light microscopy, confocal scanning laser microscopy and transmission electron microscopy, so that the possible relation between neem action and further impairment in these ectoparasites feed performance could be established. Neem oil demonstrated a clear dose-dependent effect in the analyzed samples. The agranular (type I) and granular acini (types II and III) showed, particularly in individuals treated with the highest concentrations of the product, cells with irregular shape, intense cytoplasmic disorganization and vacuolation, dilation of rough endoplasmic reticulum lumen, besides alterations in mitochondrial intermembrane space. These morphological damages may indicate modifications in salivary glands physiology, demonstrating the harmful effects of compounds present in neem oil on ticks. These results reinforce the potential of neem as an alternative method for controlling R. sanguineus ticks, instead of synthetic acaricides. PMID:26852009

  2. Morphological alterations in salivary glands of Rhipicephalus sanguineus ticks (Acari: Ixodidae) exposed to neem seed oil with known azadirachtin concentration.

    PubMed

    Remedio, R N; Nunes, P H; Anholeto, L A; Oliveira, P R; Sá, I C G; Camargo-Mathias, M I

    2016-04-01

    Neem (Azadirachta indica) has attracted the attention of researchers worldwide due to its repellent properties and recognized effects on the morphology and physiology of arthropods, including ticks. Therefore, this study aimed to demonstrate the effects of neem seed oil enriched with azadirachtin on salivary glands of Rhipicephalus sanguineus ticks, targets of great veterinary interest because of their ability to transmit pathogens to dogs. For this, R. sanguineus semi-engorged females were subjected to treatment with neem seed oil, with known azadirachtin concentrations (200, 400 and 600ppm). After dissection, salivary glands were collected and evaluated through morphological techniques in light microscopy, confocal scanning laser microscopy and transmission electron microscopy, so that the possible relation between neem action and further impairment in these ectoparasites feed performance could be established. Neem oil demonstrated a clear dose-dependent effect in the analyzed samples. The agranular (type I) and granular acini (types II and III) showed, particularly in individuals treated with the highest concentrations of the product, cells with irregular shape, intense cytoplasmic disorganization and vacuolation, dilation of rough endoplasmic reticulum lumen, besides alterations in mitochondrial intermembrane space. These morphological damages may indicate modifications in salivary glands physiology, demonstrating the harmful effects of compounds present in neem oil on ticks. These results reinforce the potential of neem as an alternative method for controlling R. sanguineus ticks, instead of synthetic acaricides.

  3. EC Transmission Line Risk Identification and Analysis

    SciTech Connect

    Bigelow, Tim S

    2012-04-01

    The purpose of this document is to assist in evaluating and planning for the cost, schedule, and technical project risks associated with the delivery and operation of the EC (Electron cyclotron) transmission line system. In general, the major risks that are anticipated to be encountered during the project delivery phase associated with the implementation of the Procurement Arrangement for the EC transmission line system are associated with: (1) Undefined or changing requirements (e.g., functional or regulatory requirements) (2) Underperformance of prototype, first unit, or production components during testing (3) Unavailability of qualified vendors for critical components Technical risks associated with the design and operation of the system are also identified.

  4. Public Availability to ECS Collected Datasets

    NASA Astrophysics Data System (ADS)

    Henderson, J. F.; Warnken, R.; McLean, S. J.; Lim, E.; Varner, J. D.

    2013-12-01

    Coastal nations have spent considerable resources exploring the limits of their extended continental shelf (ECS) beyond 200 nm. Although these studies are funded to fulfill requirements of the UN Convention on the Law of the Sea, the investments are producing new data sets in frontier areas of Earth's oceans that will be used to understand, explore, and manage the seafloor and sub-seafloor for decades to come. Although many of these datasets are considered proprietary until a nation's potential ECS has become 'final and binding' an increasing amount of data are being released and utilized by the public. Data sets include multibeam, seismic reflection/refraction, bottom sampling, and geophysical data. The U.S. ECS Project, a multi-agency collaboration whose mission is to establish the full extent of the continental shelf of the United States consistent with international law, relies heavily on data and accurate, standard metadata. The United States has made it a priority to make available to the public all data collected with ECS-funding as quickly as possible. The National Oceanic and Atmospheric Administration's (NOAA) National Geophysical Data Center (NGDC) supports this objective by partnering with academia and other federal government mapping agencies to archive, inventory, and deliver marine mapping data in a coordinated, consistent manner. This includes ensuring quality, standard metadata and developing and maintaining data delivery capabilities built on modern digital data archives. Other countries, such as Ireland, have submitted their ECS data for public availability and many others have made pledges to participate in the future. The data services provided by NGDC support the U.S. ECS effort as well as many developing nation's ECS effort through the U.N. Environmental Program. Modern discovery, visualization, and delivery of scientific data and derived products that span national and international sources of data ensure the greatest re-use of data and

  5. Grout Analysis for EC and CC Calorimeters

    SciTech Connect

    Engstrom, L.L.; /Fermilab

    1987-01-06

    The EC and CC calorimeters roll on Two parallel hardened steel ways which reside on the top of the D0 platform's center beam. The ways will be grouted to the center beam once their correct elevation has been established. The purpose of this report is to evaluate and compare three different epoxy grouts and their properties for this application.

  6. EC's carbon tax seen yielding little effect

    SciTech Connect

    Not Available

    1991-12-23

    This paper reports on a proposed carbon tax that may reduce European Community demand for petroleum products by only 0.2%/year to 2000. To help European countries stabilize carbon dioxide emissions at the 1990 level by the end of the century, the commission of the EC proposed a tax equal to No. 3/bbl of oil equivalent (BOE) starting in 1993.

  7. Efficacy of Insecticide and Bioinsecticide Ground Sprays to Control Metisa plana Walker (Lepidoptera: Psychidae) in Oil Palm Plantations, Malaysia.

    PubMed

    Salim, Hasber; Rawi, Che Salmah Md; Ahmad, Abu Hassan; Al-Shami, Salman Abdo

    2015-12-01

    The effectiveness of the synthetic insecticides trichlorfon, lambda-cyhalothrin, cypermethrin emulsion concentrated (EC) and cypermethrin emulsion water based (EW) and a bio-insecticide, Bacillus thuringiensis subsp. kurstaki (Btk), was evaluated at 3, 7, 14 and 30 days after treatment (DAT) for the control of Metisa plana larvae in an oil palm (Elaeis guineensis) plantation in Malaysia. Although all synthetic insecticides effectively reduced the larval population of M. plana, trichlorfon, lambda-cyhalothrin and cypermethrin EC were the fastest-acting. The larval population dropped below the economic threshold level (ETL) 30 days after a single application of the synthetic insecticides. Application of Btk, however, gave poor results, with the larval population remaining above the ETL post treatment. In terms of operational productivity, ground spraying using power spray equipment was time-consuming and resulted in poor coverage. Power spraying may not be appropriate for controlling M. plana infestations in large fields. Using a power sprayer, one man could cover 2-3 ha per day. Hence, power spraying is recommended during outbreaks of infestation in areas smaller than 50 ha.

  8. Insecticide Recommendations for Arkansas. MP 144.

    ERIC Educational Resources Information Center

    Jones, Bill F.; Barnes, Gordon

    This publication gives, in chart form, insecticides for use on animals, field crops, fruits, flowers, trees and shrubs, household pests, recreation areas, lawn and turf grass, pecans, stored grain, and vegetables. Included in the charts are the insecticides recommended for each insect, formulation to be used, amount, time to apply, and other…

  9. Scalable synthesis of aligned carbon nanotubes bundles using green natural precursor: neem oil

    NASA Astrophysics Data System (ADS)

    Kumar, Rajesh; Tiwari, Radhey Shyam; Srivastava, Onkar Nath

    2011-12-01

    Practical application of aligned carbon nanotubes (ACNTs) would have to be determined by a matter of its economical and large-scale preparation. In this study, neem oil (also named Margoaa oil, extracted from the seeds of the neem-- Azadirachta indica) was used as carbon source to fabricate the bundles of ACNTs. ACNTs have been synthesized by spray pyrolysis of neem oil and ferrocene mixture at 825°C. The major components of neem oil are hydrocarbon with less amount of oxygen, which provided the precursor species in spray pyrolysis growth of CNTs. The bundles of ACNTs have been grown directly inside the quartz tube. The as-grown ACNTs have been characterized through Raman spectroscopy, scanning and transmission electron microscopic (SEM/TEM) techniques. SEM images reveal that the bundles of ACNTs are densely packed and are of several microns in length. High-resolution TEM analysis reveals these nanotubes to be multi-walled CNTs. These multi-walled CNTs were found to have inner diameter between 15 and 30 nm. It was found that present technique gives high yield with high density of bundles of ACNTs.

  10. Effects of spinosad and neem on the efficacy of a nucleopolyhedrovirus on pickleworm larvae

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A neem formulation (Neemix® 4.5) and spinosad (SpinTor® 2SC) were tested for their effects when mixed with the multicapsid nucleopolyhedrovirus virus (AgMNPV) from the velvetbean caterpillar, Anticarsia gemmatalis Hübner (Lepidoptera: Noctuidae), for control of pickleworm larvae, Diaphania nitidalis...

  11. Nimbolide B and nimbic acid B, phytotoxic substances in neem leaves with allelopathic activity.

    PubMed

    Kato-Noguchi, Hisashi; Salam, Md Abdus; Ohno, Osamu; Suenaga, Kiyotake

    2014-05-26

    Neem (Azadirachta indica) has been widely used as a traditional medicine and several bioactive compounds have been isolated from this species, but to date no potent allelopathic active substance has been reported. Therefore, we investigated possible allelopathic property and phytotoxic substances with allelopathic activity in neem. An aqueous methanol extract of neem leaves inhibited the growth of roots and shoots of cress, lettuce, alfalfa, timothy, crabgrass, ryegrass, barnyard grass and jungle rice. The extracts were then purified by several chromatographic runs while monitoring the inhibitory activity and two phytotoxic substances were isolated. The chemical structures of the two substances were determined by spectral data to correspond to novel compounds, nimbolide B (1) and nimbic acid B (2). Nimbolide B inhibited the growth of cress and barnyard grass at concentrations greater than 0.1‒3.0 μM. Nimbic acid B inhibited the growth of cress and barnyard grass at concentrations greater than 0.3-1.0 μM. These results suggest that nimbolide B and nimbic acid B may contribute to the allelopathic effects caused by neem leaves.

  12. Inquiry-based Investigation in Biology Laboratories: Does Neem Provide Bioprotection against Bean Beetles?

    ERIC Educational Resources Information Center

    Pearce, Amy R.; Sale, Amanda Lovelace; Srivatsan, Malathi; Beck, Christopher W.; Blumer, Lawrence S.; Grippo, Anne A.

    2013-01-01

    We developed an inquiry-based biology laboratory exercise in which undergraduate students designed experiments addressing whether material from the neem tree ("Azadirachta indica") altered bean beetle ("Callosobruchus maculatus") movements and oviposition. Students were introduced to the bean beetle life cycle, experimental…

  13. Variations of ion concentrations in the deep ice core and surface snow at NEEM, Greenland

    NASA Astrophysics Data System (ADS)

    Goto-Azuma, K.; Wegner, A.; Hansson, M.; Hirabayashi, M.; Kuramoto, T.; Miyake, T.; Motoyama, H.; NEEM Aerosol Consortium members

    2012-04-01

    Discrete samples were collected from the CFA (Continuous Flow Analysis) melt fractions during the field campaign carried out at NEEM, Greenland in 2009-2011, and were distributed to different laboratories. Ionic species were analyzed at National Institute of Polar Research (Japan) and Alfred Wegener Institute for Polar and Marine Research (Germany). Here we present and compare the ion concentration data obtained by both institutes. Most of the ions show good agreement between the two institutes. As is indicated with the CFA data (Bigler and the NEEM Aerosol Consortium members, EGU 2012), ion chromatograph data also display that calcium and sodium, mainly originated from terrestrial dust and sea-salt, respectively, show large variations associated with Dansgaard-Oeschger (DO) events. Chloride, fluoride, sulfate, sodium, potassium and magnesium also show such variations, as has been already reported for other Greenland ice cores. New ion data obtained from the NEEM deep core also show large variability of oxalate and phosphate concentrations during DO events. Acetate, which is thought to be mainly derived from biomass burning, as is oxalate, appears to show variability associated with DO events, but to a lesser extent. On the other hand, nitrate, ammonium and methanesulfonate do not show such variations. Together with ion data from the deep ice core, we present those from the pits dug during the NEEM field campaign to discuss seasonal variations of ionic species. The seasonal and millennial scale variations of ions are thought to be caused by changes in atmospheric circulation and source strength.

  14. Small scale folding observed in the NEEM ice core

    NASA Astrophysics Data System (ADS)

    Jansen, Daniela; Llorens, Maria-Gema; Westhoff, Julien; Steinbach, Florian; Bons, Paul D.; Kipfstuhl, Sepp; Griera, Albert; Weikusat, Ilka

    2015-04-01

    Disturbances on the centimeter scale in the layering of the NEEM ice core (North Greenland) can be mapped by means of visual stratigraphy as long as the ice does have a visual layering, such as, for example, cloudy bands. Different focal depths of the visual stratigraphy method allow, to a certain extent, a three dimensional view of the structures. In this study we present a structural analysis of the visible folds, discuss characteristics and frequency and present examples of typical fold structures. With this study we aim to quantify the potential impact of small scale folding on the integrity of climate proxy data. We also analyze the structures with regard to the stress environment under which they formed. The structures evolve from gentle waves at about 1700 m to overturned z-folds with increasing depth. Occasionally, the folding causes significant thickening of layers. Their shape indicates that they are passive features and are probably not initiated by rheology differences between layers. Layering is heavily disturbed and tracing of single layers is no longer possible below a depth of 2160 m. Lattice orientation distributions for the corresponding core sections were analyzed where available in addition to visual stratigraphy. The data show axial-plane parallel strings of grains with c.axis orientations that deviate from that of the matrix, which has more or less a single-maximum fabric at the depth where the folding occurs. We conclude from these data that folding is a consequence of deformation along localized shear planes and kink bands. The findings are compared with results from other deep ice cores. The observations presented are supplemented by microstructural modeling using a crystal plasticity code that reproduces deformation, applying a Fast Fourier Transform (FFT), coupled with ELLE to include dynamic recrystallization processes. The model results reproduce the development of bands of grains with a tilted orientation relative to the single maximum

  15. Insecticide resistance in Anopheles sacharovi

    PubMed Central

    de Zulueta, Julian

    1959-01-01

    A series of observations is presented on the susceptibility or resistance to insecticides of Anopheles sacharovi in Greece, Iran, Italy, Romania and Turkey. High physiological resistance to DDT was observed in the Tarsus area of southern Turkey. In Greece very marked physiological resistance to dieldrin was found in all the areas examined and was associated, at least in the Peloponnese, with similar resistance to DDT, affecting, however, only a part of the sacharovi population. In Italy and Romania, after 10 years' use of DDT, sacharovi is still susceptible to it; long use of BHC in Romania has not resulted in the development of resistance to dieldrin or to BHC. Further investigation of the situation in Iran is considered necessary. The fact that the use of DDT in Greece, after the development of resistance to this insecticide in 1951, has not resulted in the formation of a highly resistant mosquito population is considered to be due to the irritant effect of the DDT on susceptible mosquitos, causing them to leave sprayed surfaces before they have picked up a lethal dose. The information to date points to the existence in A. sacharovi of two independent mechanisms of physiological resistance—one to DDT and another to dieldrin and BHC—which may or may not be present together. PMID:13847916

  16. Fabric along the NEEM ice core, Greenland, and its comparison with GRIP and NGRIP ice cores

    NASA Astrophysics Data System (ADS)

    Montagnat, M.; Azuma, N.; Dahl-Jensen, D.; Eichler, J.; Fujita, S.; Gillet-Chaulet, F.; Kipfstuhl, S.; Samyn, D.; Svensson, A.; Weikusat, I.

    2014-07-01

    Fabric (distribution of crystallographic orientations) along the full NEEM ice core, Greenland was measured in the field by an automatic ice texture analyzer every 10 m, from 33 m down to 2461 m depth. The fabric evolves from a slightly anisotropic fabric at the top, toward a strong single maximum at about 2300 m, which is typical of a deformation pattern mostly driven by uniaxial compression and simple shearing. A sharp increase in the fabric strengthening rate is observed at the Holocene to Wisconsin (HW) climatic transition. From a simple model we estimate that this depth is located at a transition from a state dominated by vertical compression to a state dominated by vertical shear. Comparisons are made to two others ice cores drilled along the same ridge; the GRIP ice core, drilled at the summit of the ice sheet, and the NGRIP ice core, drilled 325 km to the NNW of the summit along the ridge, and 365 km upstream from NEEM. This comparison tends to demonstrate that the ice viscosity change with the HW climatic transition must be associated with the shear-dominated state to induce the abrupt fabric strengthening observed at NEEM. This comparison therefore reflects the increasing role of shear deformation on the coring site when moving NW along the ridge from GRIP to NGRIP and NEEM. The difference in fabric profiles between NEEM and NGRIP also evidences a stronger lateral extension associated with a sharper ridge at NGRIP. Further along the core, centimeter scale abrupt texture (fabric and microstructure) variations are observed in the bottom part of the core. Their positions are in good agreement with the observed folding layers in Dahl-Jensen et al. (2013).

  17. Recent North West Greenland climate variability documented by NEEM shallow ice cores

    NASA Astrophysics Data System (ADS)

    Masson-Delmotte, Valérie; Steen-Larsen, Hans-Christian; Popp, Trevor; Vinther, Bo; Oerter, Hans; Ortega, Pablo; White, Jim; Orsi, Anais; Falourd, Sonia; Minster, Benedicte; Jouzel, Jean; Landais, Amaelle; Risi, Camille; Werner, Martin; Swingedouw, Didier; Fettweis, Xavier; Gallée, Hubert; Sveinbjornsdottir, Arny; Gudlaugsdottir, Hera; Box, Jason

    2014-05-01

    Short water stable isotope records obtained from NEEM ice cores (North West Greenland) have been shown to be sensitive to NW Greenland temperature variations, and sea-ice extent in the Baffin Bay area (Steen-Larsen et al, JGR, 2011), with maximum snowfall deposition during summer, therefore providing information complementary to other Greenland ice core records. At the NEEM deep drilling camp, several snow pits and shallow ice cores have been retrieved and analysed at high resolution (seasonal to annual) for water stable isotopes using mass spectrometry and laser instruments in order to document recent climate variability, complementing and facilitating the interpretation of the long records obtained from the deep ice core which extends back to the last interglacial period (NEEM, Nature, 2013). The different pits and shallow ice core records allow to document the signal to noise ratio and to produce a robust stack back to 1750, and up to 2011. The stack record of annual mean d18O depicts a recent isotopic enrichment in parallel with the Greenland warming inferred from coastal weather stations, and shows that many features of decadal variations are in fact well captured by the low resolution profiles measured along the deep ice core data. Recent variations can therefore be compared to long-term trends and centennial variations of the last Holocene, documented at about 5 year resolution. For the past decades to centuries, the NEEM isotopic records are compared with estimations and simulations of local temperature for different seasons, results from NEEM borehole temperature inversions, d18O records from other Greenland ice cores, large scale modes of variability (NAO and AMO) and with simulations from atmospheric general circulation models equiped with water stable isotopes.

  18. Compatibility of the insect pathogenic fungus Beauveria bassiana with neem against sweetpotato whitefly, Bemisia tabaci, on eggplant

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A study on the compatibility of the entomopathogenic fungus Beauveria bassiana (Balsamo) Vuillemin (Ascomycota: Hypocreales) with neem was conducted against sweetpotato whitefly, Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae), on eggplant. Initially, three concentrations of B. bassiana (106, 1...

  19. Insecticide Control of Vector-Borne Diseases: When Is Insecticide Resistance a Problem?

    PubMed Central

    Rivero, Ana; Vézilier, Julien; Weill, Mylène; Read, Andrew F.; Gandon, Sylvain

    2010-01-01

    Many of the most dangerous human diseases are transmitted by insect vectors. After decades of repeated insecticide use, all of these vector species have demonstrated the capacity to evolve resistance to insecticides. Insecticide resistance is generally considered to undermine control of vector-transmitted diseases because it increases the number of vectors that survive the insecticide treatment. Disease control failure, however, need not follow from vector control failure. Here, we review evidence that insecticide resistance may have an impact on the quality of vectors and, specifically, on three key determinants of parasite transmission: vector longevity, competence, and behaviour. We argue that, in some instances, insecticide resistance is likely to result in a decrease in vector longevity, a decrease in infectiousness, or in a change in behaviour, all of which will reduce the vectorial capacity of the insect. If this effect is sufficiently large, the impact of insecticide resistance on disease management may not be as detrimental as previously thought. In other instances, however, insecticide resistance may have the opposite effect, increasing the insect's vectorial capacity, which may lead to a dramatic increase in the transmission of the disease and even to a higher prevalence than in the absence of insecticides. Either way—and there may be no simple generality—the consequence of the evolution of insecticide resistance for disease ecology deserves additional attention. PMID:20700451

  20. Toxicity of neem seed oil (Azadiracta indica) against the larvae of amblyomma variegatum a three-host tick in cattle.

    PubMed

    Ndumu, P A; George, J B; Choudhury, M K

    1999-09-01

    The in vitro toxicity of neem seed oil (Azadiracta indica, family: Meliaceae, 'Dogon yaro' in Hausa -language) was tested against the larvae of a three-host tick, Amblyomma variegatum (family: Ixodidae or hard tick) parasitic to cattle commonly found in Nigeria. Undiluted neem oil (100% concentration) was found to kill all (100% mortality) the larvae after 48 h. The toxicity was concentration and time dependent. PMID:10479769

  1. The neem [Azadirachta indica a. juss (meliaceae)] oil reduction in the in vitro production of zearalenone by Fusarium graminearum

    PubMed Central

    Geraldo, Márcia Regina Ferreira; da Costa, Christiane Luciana; Arrotéia, Carla Cristina; Kemmelmeier, Carlos

    2011-01-01

    Zearalenone, a mycotoxin produced by fungi of the genus Fusarium, including F. graminearum, triggers reproduction disorders in certain animals and hyperestrogen syndromes in humans. Current research investigates three concentrations of neem oil extract (0.1, 0.25 and 0.5%) in reducing the production of zearalenone. Neem oil extract decreased zearalenone amount in the three concentrations but highest inhibition (59.05%) occurred at 0.1%. PMID:24031683

  2. Preliminary conceptual design of DEMO EC system

    SciTech Connect

    Garavaglia, S. Bin, W.; Bruschi, A.; Granucci, G.; Moro, A.; Rispoli, N.; Grossetti, G.; Strauss, D.; Jelonnek, J.; Tran, Q. M.; Franke, T.

    2015-12-10

    In the framework of EUROfusion Consortium the Work Package Heating and Current Drive addresses the engineering design and R&D for the electron cyclotron, ion cyclotron and neutral beam systems. This paper reports the activities performed in 2014, focusing on the work done regarding the input for the conceptual design of the EC system, particularly for the gyrotron, the transmission line and the launchers.

  3. The insecticidal potential of venom peptides.

    PubMed

    Smith, Jennifer J; Herzig, Volker; King, Glenn F; Alewood, Paul F

    2013-10-01

    Pest insect species are a burden to humans as they destroy crops and serve as vectors for a wide range of diseases including malaria and dengue. Chemical insecticides are currently the dominant approach for combating these pests. However, the de-registration of key classes of chemical insecticides due to their perceived ecological and human health risks in combination with the development of insecticide resistance in many pest insect populations has created an urgent need for improved methods of insect pest control. The venoms of arthropod predators such as spiders and scorpions are a promising source of novel insecticidal peptides that often have different modes of action to extant chemical insecticides. These peptides have been optimized via a prey-predator arms race spanning hundreds of millions of years to target specific types of insect ion channels and receptors. Here we review the current literature on insecticidal venom peptides, with a particular focus on their structural and pharmacological diversity, and discuss their potential for deployment as insecticides. PMID:23525661

  4. Mosquito age and susceptibility to insecticides.

    PubMed

    Rajatileka, Shavanthi; Burhani, Joseph; Ranson, Hilary

    2011-05-01

    Insecticides play a crucial role in controlling the transmission of mosquito-borne diseases and the development and spread of insecticide resistance is a major threat to sustainable control. Guidelines developed by the WHO to monitor for insecticide resistance recommend using 1-3 day old, non blood fed female mosquitoes. This standardisation facilitates comparison between different tests, which is important when monitoring for spatial or longitudinal variations in resistance in the field. However, mosquitoes of this age cannot transmit human pathogens. In order to transmit disease, the mosquito must live long enough to pick up the pathogen via a blood meal, survive the extrinsic incubation period and then pass on the pathogen during a subsequent blood meal. Previous studies have reported declines in insecticide resistance with mosquito age. If widely applicable this would have important implications for predictions of the impact of resistance that are based on results from WHO bioassays. This study investigated the impact of senescence and blood feeding on insecticide induced mortality in six different mosquito populations and found higher mortality after insecticide exposure in older mosquitoes in three populations of Aedes aegypti and two Anopheles gambiae populations. Age dependent changes in the expression of a known insecticide detoxification gene, GSTe2, and in the frequency of a target site mutation (kdr 1014F) were investigated in an attempt to explain the results. PMID:21353689

  5. The insecticidal potential of venom peptides.

    PubMed

    Smith, Jennifer J; Herzig, Volker; King, Glenn F; Alewood, Paul F

    2013-10-01

    Pest insect species are a burden to humans as they destroy crops and serve as vectors for a wide range of diseases including malaria and dengue. Chemical insecticides are currently the dominant approach for combating these pests. However, the de-registration of key classes of chemical insecticides due to their perceived ecological and human health risks in combination with the development of insecticide resistance in many pest insect populations has created an urgent need for improved methods of insect pest control. The venoms of arthropod predators such as spiders and scorpions are a promising source of novel insecticidal peptides that often have different modes of action to extant chemical insecticides. These peptides have been optimized via a prey-predator arms race spanning hundreds of millions of years to target specific types of insect ion channels and receptors. Here we review the current literature on insecticidal venom peptides, with a particular focus on their structural and pharmacological diversity, and discuss their potential for deployment as insecticides.

  6. Multivariate calibration for the determination of total azadirachtin-related limonoids and simple terpenoids in neem extracts using vanillin assay.

    PubMed

    Dai, J; Yaylayan, V A; Raghavan, G S; Parè, J R; Liu, Z

    2001-03-01

    Two-component and multivariate calibration techniques were developed for the simultaneous quantification of total azadirachtin-related limonoids (AZRL) and simple terpenoids (ST) in neem extracts using vanillin assay. A mathematical modeling method was also developed to aid in the analysis of the spectra and to simplify the calculations. The mathematical models were used in a two-component calibration (using azadirachtin and limonene as standards) for samples containing mainly limonoids and terpenoids (such as neem seed kernel extracts). However, for the extracts from other parts of neem, such as neem leaf, a multivariate calibration was necessary to eliminate the possible interference from phenolics and other components in order to obtain the accurate content of AZRL and ST. It was demonstrated that the accuracy of the vanillin assay in predicting the content of azadirachtin in a model mixture containing limonene (25% w/w) can be improved from 50% overestimation to 95% accuracy using the two-component calibration, while predicting the content of limonene with 98% accuracy. Both calibration techniques were applied to estimate the content of AZRL and ST in different parts of the neem plant. The results of this study indicated that the relative content of limonoids was much higher than that of the terpenoids in all parts of the neem plant studied. PMID:11312830

  7. Gene amplification and insecticide resistance.

    PubMed

    Bass, Chris; Field, Linda M

    2011-08-01

    Pesticide resistance in arthropods has been shown to evolve by two main mechanisms, the enhanced production of metabolic enzymes, which bind to and/or detoxify the pesticide, and mutation of the target protein, which makes it less sensitive to the pesticide. One route that leads to enhanced metabolism is the duplication or amplification of the structural gene(s) encoding the detoxifying enzyme, and this has now been described for the three main families (esterases, glutathione S-transferases and cytochrome P450 monooxygenases) implicated in resistance. More recently, a direct or indirect role for gene duplication or amplification has been described for target-site resistance in several arthropod species. This mini-review summarises the involvement of gene duplication/amplification in the insecticide/acaricide resistance of insect and mite pests and highlights recent developments in this area in relation to P450-mediated and target-site resistance.

  8. Fungal degradation of organophosphorous insecticides

    SciTech Connect

    Bumpus, J.A.; Kakar, S.N.; Coleman, R.D.

    1992-07-01

    Organophosphorous insecticides are used extensively to treat a variety of pests and insects. Although as a group they are easily degraded by bacteria in the environment, a number of them have half-lives of several months. Little is known about their biodegradation by fungi. We have shown that Phanerochaete chrysosporium can substantially degrade chlorpyrifos, fonofos, and terbufos (27.5%, 12.2%, and 26.6%, respectively) during 18-day incubation in nitrogen-limited stationary cultures. The results demonstrate that the clorinated pyridinyl ring of chlorpyrifos and the phenyl ring of fonofos undergo ring cleavage during biodegradation by the fungus. The usefulness of the fungus system for bioremediation is discussed. 16 refs., 7 figs., 2 tabs.

  9. Fungal degradation of organophosphorous insecticides

    SciTech Connect

    Bumpus, J.A. ); Kakar, S.N.; Coleman, R.D. )

    1992-01-01

    Organophosphorous insecticides are used extensively to treat a variety of pests and insects. Although as a group they are easily degraded by bacteria in the environment, a number of them have half-lives of several months. Little is known about their biodegradation by fungi. We have shown that Phanerochaete chrysosporium can substantially degrade chlorpyrifos, fonofos, and terbufos (27.5%, 12.2%, and 26.6%, respectively) during 18-day incubation in nitrogen-limited stationary cultures. The results demonstrate that the clorinated pyridinyl ring of chlorpyrifos and the phenyl ring of fonofos undergo ring cleavage during biodegradation by the fungus. The usefulness of the fungus system for bioremediation is discussed. 16 refs., 7 figs., 2 tabs.

  10. Comparative laboratory toxicity of neem pesticides to honey bees (Hymenoptera: Apidae), their mite parasites Varroa jacobsoni (Acari: Varroidae) and Acarapis woodi (Acari: Tarsonemidae), and brood pathogens Paenibacillus larvae and Ascophaera apis.

    PubMed

    Melathopoulos, A P; Winston, M L; Whittington, R; Smith, T; Lindberg, C; Mukai, A; Moore, M

    2000-04-01

    Laboratory bioassays were conducted to evaluate neem oil and neem extract for the management of key honey bee (Apis mellifera L.) pests. Neem pesticides inhibited the growth of Paenibacillus larvae (Ash, Priest & Collins) in vitro but had no effect on the growth of Ascophaera apis (Olive & Spiltoir). Azadirachtin-rich extract (neem-aza) was 10 times more potent than crude neem oil (neem oil) against P. larvae suggesting that azadirachtin is a main antibiotic component in neem. Neem-aza, however, was ineffective at controlling the honey bee mite parasites Varroa jacobsoni (Ouduemans) and Acarapis woodi (Rennie). Honey bees also were deterred from feeding on sucrose syrup containing > 0.01 mg/ml of neem-aza. However, neem oil applied topically to infested bees in the laboratory proved highly effective against both mite species. Approximately 50-90% V. jacobsoni mortality was observed 48 h after treatment with associated bee mortality lower than 10%. Although topically applied neem oil did not result in direct A. woodi mortality, it offered significant protection of bees from infestation by A. woodi. Other vegetable and petroleum-based oils also offered selective control of honey bee mites, suggesting neem oil has both a physical and a toxicological mode of action. Although oils are not as selective as the V. jacobsoni acaricide tau-fluvalinate, they nonetheless hold promise for the simultaneous management of several honey bee pests. PMID:10826163

  11. History of insecticide resistance of Triatominae vectors.

    PubMed

    Pessoa, Grasielle Caldas Dávila; Vinãs, Pedro Albajar; Rosa, Aline Cristine Luiz; Diotaiuti, Liléia

    2015-01-01

    In the last 15 years, different types of Triatominae resistance to different insecticides have been reported; thus, resistance may be more widespread than known, requiring better characterization and delimitation, which was the aim of this review. This review was structured on a literature search of all articles from 1970 to 2015 in the PubMed database that contained the keywords Insecticide resistance and Triatominae . Out of 295 articles screened by title, 33 texts were selected for detailed analysis. Insecticide resistance of Triatomines is a complex phenomenon that has been primarily reported in Argentina and Bolivia, and is caused by different factors (associated or isolated). Insecticide resistance of Triatominae is a characteristic inherited in an autosomal and semi-dominant manner, and is polygenic, being present in both domestic and sylvatic populations. The toxicological profile observed in eggs cannot be transposed to different stages of evolution. Different toxicological profiles exist at macro- and microgeographical levels. The insecticide phenotype has both reproductive and developmental costs. Different physiological mechanisms are involved in resistance. Studies of Triatomine resistance to insecticides highlight three deficiencies in interpreting the obtained results: I) the vast diversity of methodologies, despite the existence of a single guiding protocol; II) the lack of information on the actual impact of resistance ratios in the field; and III) the concept of the susceptibility reference lineage. Research on the biological and behavioral characteristics of each Triatominae species that has evolved resistance is required in relation to the environmental conditions of each region.

  12. Insecticidal sugar baits for adult biting midges.

    PubMed

    Snyder, D; Cernicchiaro, N; Allan, S A; Cohnstaedt, L W

    2016-06-01

    The mixing of an insecticide with sugar solution creates an oral toxin or insecticidal sugar bait (ISB) useful for reducing adult insect populations. The ability of ISBs to kill the biting midge Culicoides sonorensis Wirth and Jones (Diptera: Ceratopogonidae), a vector of bluetongue virus, epizootic hemorrhagic disease and vesicular stomatitis viruses, was tested. The commercial insecticide formulations (percentage active ingredient) tested included bifenthrin, cyfluthrin, deltamethrin, permethrin, dinotefuran, imidacloprid, thiamethoxam and spinosad. Mortality rates were determined for various concentrations of commercial formulations (0.01, 0.05, 0.1, 1, 2 and 3%) and observed at 1, 4, 10 and 24 h post-exposure to the ISB. In the first set of assays, laboratory-reared midges were fed sugar ad libitum and then exposed to insecticide-treated sugar solutions to measure mortality. The second assay assessed competitive feeding: midges were provided with a control sugar solution (10% sucrose) in one vial, and a sugar and insecticide solution in another. Pyrethroid treatments resulted in the greatest mortality in the first hour at the lowest concentrations and spinosad consumption resulted in the least mortality. Biting midges were not deterred from feeding on the 1% ISB solutions despite the presence of an insecticide-free alternative source of sugar. PMID:26789534

  13. Impact of insecticides on the invasive Halyomorpha halys (Hemiptera: Pentatomidae): analysis of insecticide lethality.

    PubMed

    Leskey, Tracy C; Lee, Doo-Hyung; Short, Brent D; Wright, Starker E

    2012-10-01

    The efficacy of 37 insecticide treatments against adult Halyomorpha halys (Stål) was established based on exposure to 18-h old dry insecticide residue in laboratory bioassays. Individual adult H. halys were exposed to an insecticide residue for 4.5 h and then monitored daily for survivorship over a 7-d period. The proportion of dead and moribund insects was used as an estimate of overall insecticide efficacy against H. halys immediately after the exposure period and over the 7-d trial. Among all materials evaluated, 14 insecticides exhibited increasing efficacy, in which the percentage of dead and moribund insects (used as a measure of insecticide efficacy) increased by > 10% after 7 d. By contrast, insecticide efficacy values of eight insecticides declined by > 10% (based on recovery of adults from a moribund state) over the 7-d period with most belonging to the pyrethroid class. In this study, the efficacy value of neonicotinoid, acetamiprid, showed the greatest decline from 93 to 10% over 7 d. A lethality index (scale of 0-100) was developed to compare insecticides based on quantifying the immediate and longer-term effects of insecticide exposure on H. halys. Among all materials evaluated, dimethoate, malathion, bifenthrin, methidathion, endosulfan, methomyl, chlorpyrifos, acephate, fenpropathrin, and permethrin yielded the highest values (> 75) because of a high degree of immediate mortality with very little recovery. Our results provide baseline information regarding potential of candidate insecticides against adult H. halys and highlight the need to consider longer-term effects in establishing overall efficacy ratings against this invasive species. PMID:23156170

  14. Rapid, Bioassay-Guided Process for the Detection and Identification of Antibacterial Neem Oil Compounds.

    PubMed

    Krüzselyi, Dániel; Nagy, Róbert; Ott, Péter G; Móricz, Ágnes M

    2016-08-01

    Bioassay guidance was used along the whole process including method development, isolation and identification of antibacterial neem (Azadirachta indica) oil compounds. The biomonitoring was performed by direct bioautography (DB), a combination of thin-layer chromatography (TLC) and antimicrobial detection. DB of neem oil showed one antibacterial zone that was not UV-active; therefore, the TLC separation was improved under DB control. The chromatographic zone that exhibited activity against Bacillus subtilis, Xanthomonas euvesicatoria, Aliivibrio fischeri, Staphylococcus aureus and methicillin-resistant Staphylococcus aureus was characterized by TLC reagents, indicating a lipophilic, fatty acid-like chemical feature. Two compounds were found and identified in the active zone by high-performance liquid chromatography-electrospray ionization mass spectrometry as linoleic and oleic acids. Both fatty acids inhibited B. subtilis, but A. fischeri was sensitive only against linoleic acid.

  15. Synthesis and characterization of zinc oxide-neem oil-chitosan bionanocomposite for food packaging application.

    PubMed

    Sanuja, S; Agalya, A; Umapathy, M J

    2015-03-01

    Nano zinc oxide at different concentrations (0.1, 0.3 and 0.5%) and neem essential oil were incorporated into the chitosan polymer by solution cast method to enhance the properties of the bionanocomposite film. The functional groups, crystalline particle size, thermal stability and morphology were determined using FTIR, XRD, TGA and SEM, respectively. The results showed that 0.5% nano zinc oxide incorporated composite film have improved tensile strength, elongation, film thickness, film transparency and decreased water solubility, swelling and barrier properties due to the presence of neem oil and nano zinc oxide in the polymer matrix. Further antibacterial activity by well diffusion assay method was followed against Escherichia coli which were found to have good inhibition effect. In addition to this food quality application were carried against carrot and compared with the commercial film.

  16. Acute toxicity study of the oil from Azadirachta indica seed (neem oil).

    PubMed

    Gandhi, M; Lal, R; Sankaranarayanan, A; Banerjee, C K; Sharma, P L

    1988-01-01

    The seed oil of Azadirachta indica (neem oil) is well known for its medicinal properties in the indigenous Indian system of medicine. Its acute toxicity was documented in rats and rabbits by the oral route. Dose-related pharmacotoxic symptoms were noted along with a number of biochemical and histopathological indices of toxicity. The 24-h LD50 was established as 14 ml/kg in rats and 24 ml/kg in rabbits. Prior to death, animals of both species exhibited comparable pharmacotoxic symptoms in order and severity, with lungs and central nervous system as the target organs of toxicity. Edible mustard seed oil (80 ml/kg) was tested in the same manner to document the degree to which the physical characteristics of an oil could contribute to the oral toxicity of neem oil. PMID:3419203

  17. Efficacy of neem seed extract shampoo on head lice of naturally infected humans in Egypt.

    PubMed

    Abdel-Ghaffar, Fathy; Semmler, Margit

    2007-01-01

    Sixty heavily lice-infested male and female children (4-15 years) were selected and subjected to the treatment with a neem seed extract shampoo. Twenty to thirty milliliter of the shampoo were thoroughly mixed with completely wet hair and rubbed in to reach the skin of the scalp. After 5, 10, 15 and 30 min, the shampoo was washed out and the hair basically combed. Head lice were collected and examined. The neem seed extract shampoo proved to be highly effective against all stages of head lice. No obvious differences regarding the efficacy of the shampoo were observed between an exposure time of 10, 15 or 30 min. No side effects, such as skin irritation, burning sensations, or red spots on the scalp, forehead or neck, respectively, were observed.

  18. Synthesis and characterization of zinc oxide-neem oil-chitosan bionanocomposite for food packaging application.

    PubMed

    Sanuja, S; Agalya, A; Umapathy, M J

    2015-03-01

    Nano zinc oxide at different concentrations (0.1, 0.3 and 0.5%) and neem essential oil were incorporated into the chitosan polymer by solution cast method to enhance the properties of the bionanocomposite film. The functional groups, crystalline particle size, thermal stability and morphology were determined using FTIR, XRD, TGA and SEM, respectively. The results showed that 0.5% nano zinc oxide incorporated composite film have improved tensile strength, elongation, film thickness, film transparency and decreased water solubility, swelling and barrier properties due to the presence of neem oil and nano zinc oxide in the polymer matrix. Further antibacterial activity by well diffusion assay method was followed against Escherichia coli which were found to have good inhibition effect. In addition to this food quality application were carried against carrot and compared with the commercial film. PMID:25499891

  19. Rapid, Bioassay-Guided Process for the Detection and Identification of Antibacterial Neem Oil Compounds.

    PubMed

    Krüzselyi, Dániel; Nagy, Róbert; Ott, Péter G; Móricz, Ágnes M

    2016-08-01

    Bioassay guidance was used along the whole process including method development, isolation and identification of antibacterial neem (Azadirachta indica) oil compounds. The biomonitoring was performed by direct bioautography (DB), a combination of thin-layer chromatography (TLC) and antimicrobial detection. DB of neem oil showed one antibacterial zone that was not UV-active; therefore, the TLC separation was improved under DB control. The chromatographic zone that exhibited activity against Bacillus subtilis, Xanthomonas euvesicatoria, Aliivibrio fischeri, Staphylococcus aureus and methicillin-resistant Staphylococcus aureus was characterized by TLC reagents, indicating a lipophilic, fatty acid-like chemical feature. Two compounds were found and identified in the active zone by high-performance liquid chromatography-electrospray ionization mass spectrometry as linoleic and oleic acids. Both fatty acids inhibited B. subtilis, but A. fischeri was sensitive only against linoleic acid. PMID:26951543

  20. Antifeedant activity of extracts from neem,Azadirachta indica, to strawberry aphid,Chaetosiphon fragaefolii.

    PubMed

    Lowery, D T; Isman, M B

    1993-08-01

    Leaf disk choice test bioassays demonstrated that formulated neem seed oil (NSO) was equally deterrent to first- and third-instar nymphs and adult strawberry aphids,Chaetosiphon fragaefolii (Cockerell). Concentrations of NSO resulting in 50% feeding deterrence were approximately 1.1% for this species. The rapid disruption of aphid feeding (<1 hr) was not related to the presence of the limonoid azadirachtin, and deterrence likely results from the combined activity of several compounds. Activity toC. fragaefolii disappeared within 12-24 hr following application to strawberry in the greenhouse. NSO was deterrent to only half of the six aphid species tested. The antifeedant properties of neem do not appear to contribute significantly to the control of aphids and the viruses they transmit. PMID:24249239

  1. Antibacterial activity of Karanj (Pongamia pinnata) and Neem (Azadirachta indica) seed oil: a preliminary report.

    PubMed

    Baswa, M; Rath, C C; Dash, S K; Mishra, R K

    2001-01-01

    The antibacterial activity of Karanj (Pongamia pinnata) and Neem (Azadirachta indica) seed oil in vitro against fourteen strains of pathogenic bacteria was assessed. Using the tube dilution technique, it was observed that 57.14 and 21.42% of the pathogens were inhibited at 500 microl/ml; 14.28 and 71.42% at 125 microl/ml; and 28.57 and 7.14% at 250 microl/ml of Karanj and Neem oils, respectively. The activity with both the oils was bactericidal and independent of temperature and energy. Most of the pathogens were killed more rapidly at 4 degrees C than 37 degrees C. The activity was mainly due to the inhibition of cell-membrane synthesis in the bacteria. PMID:11414503

  2. Actin cytoskeleton as a putative target of the neem limonoid Azadirachtin A.

    PubMed

    Anuradha, Aritakula; Annadurai, Ramaswamy S; Shashidhara, L S

    2007-06-01

    Limonoids isolated from the Indian neem tree (Azadirachta indica) have been gaining global acceptance in agricultural applications and in contemporary medicine for their myriad but discrete properties. However, their mode of action is still not very well understood. We have studied the mode of action of Azadirachtin A, the major limonoid of neem seed extracts, using Drosophila melanogaster as the model system. Azadirachtin A induces moderate-to-severe phenotypes in different tissues in a dose-dependent manner. At the cellular level, Azadirachtin A induces depolymerization of Actin leading to arrest of cells and subsequently apoptosis in a caspase-independent manner. Azadirachtin A-induced phenotypes were rescued by the over-expression of Cyclin E in a tissue-dependent manner. Cyclin E, which caused global rescue of Azadirachtin A-induced phenotypes, also effected rearrangement of the actin filaments. These results suggest that probably actin is a target of Azadirachtin A activity. PMID:17517339

  3. Extraction and colorimetric determination of azadirachtin-related limonoids in neem seed kernel.

    PubMed

    Dai, J; Yaylayan, V A; Raghavan, G S; Parè, J R

    1999-09-01

    A colorimetric method was developed for the determination of total azadirachtin-related limonoids (AZRL) in neem seed kernel extracts. The method employed acidified vanillin solution in methanol for the colorization of the standard azadirachtin or neem seed kernel extracts in dichloromethane. Through the investigation of various factors influencing the sensitivity of detection, such as the concentration of vanillin, acid, and the time required for the formation of color, optimum conditions were selected to perform the assay. Under the optimum conditions, a good linearity was found between the absorbance at 577 nm and the concentration of standard azadirachtin solution in the range of 0.01-0.10 mg/mL. In addition, different extraction procedures were evaluated using the vanillin assay. The HPLC analysis of the extracts indicated that if the extractions were performed in methanol followed by partitioning in dichloromethane, approximately 50% of the value determined by the vanillin assay represents azadirachtin content. PMID:10552715

  4. Efficacy of neem seed extract shampoo on head lice of naturally infected humans in Egypt.

    PubMed

    Abdel-Ghaffar, Fathy; Semmler, Margit

    2007-01-01

    Sixty heavily lice-infested male and female children (4-15 years) were selected and subjected to the treatment with a neem seed extract shampoo. Twenty to thirty milliliter of the shampoo were thoroughly mixed with completely wet hair and rubbed in to reach the skin of the scalp. After 5, 10, 15 and 30 min, the shampoo was washed out and the hair basically combed. Head lice were collected and examined. The neem seed extract shampoo proved to be highly effective against all stages of head lice. No obvious differences regarding the efficacy of the shampoo were observed between an exposure time of 10, 15 or 30 min. No side effects, such as skin irritation, burning sensations, or red spots on the scalp, forehead or neck, respectively, were observed. PMID:16900389

  5. Effect of Neem oil and Haridra on non-healing wounds

    PubMed Central

    Singh, Anjali; Singh, Anil Kumar; Narayan, G.; Singh, Teja B.; Shukla, Vijay Kumar

    2014-01-01

    Background: In Ayurveda, Vrana (wound) has stated as tissue destruction and discoloration of viable tissue due to various etiology. In Sushruta Samhita, Sushruta described Vrana as a main subject. Most commonly Vrana can be classified into Shuddha and Dushta Vrana (chronic wound/nonhealing ulcers). Among the various drugs mentioned for Dushta Vrana, two of them, Neem (Azadirechta indica A. Juss) oil and Haridra (Curcuma longa Linn.) powder are selected for their wide spectrum action on wound. Aim: To compare the effect of Neem oil and Haridra in the treatment of chronic non-healing wounds. Materials and Methods: Total 60 patients of wounds with more than 6 weeks duration were enrolled and alternatively allocated to Group I (topical application of Neem oil), Group II (Haridra powder capsules, 1 g 3 times orally) and Group III (both drugs). Duration of treatment was considered until complete healing of the wound, whereas 4th and 8th week were considered for assessment of 50% healing. Wound size was measured and recorded at weekly intervals. Wound biopsy was repeated after 4 weeks for assessment of angiogenesis and deoxyribonucleic acid (DNA) analysis. Results: After 8 weeks of treatment, 50% wound healing was observed in 43.80% patients of Group I, 18.20% patients of Group II, and 70.00% patients of Group III. Microscopic angiogenesis grading system scores and DNA concentration showed highly significant effect of combined use of both drugs when compared before and after results of treatment (P < 0.001). Conclusion: Topical use of Neem oil and oral use of Haridra powder capsule used in combination were found effective for chronic non-healing wounds. PMID:26195902

  6. Seismic Imaging of Sub-Glacial Sediments at Jakobshavn Isbræ and NEEM Greenland

    NASA Astrophysics Data System (ADS)

    Tsoflias, G. P.; Velez-Gonzalez, J. A.; Black, R. A.; van der Veen, C. J.

    2015-12-01

    Sub-glacial sediment conditions can have a major control on glacier flow yet these are difficult to measure directly. We present active source seismic reflection experiments that imaged sub-glacial sections at Jakobshavn Isbræ, West Greenland and at the North Greenland Eemian Ice Drilling (NEEM) location. At Jakobshavn Isbræ we re-processed an existing 9.8 km-long high-resolution seismic line using an iterative approach to determine seismic velocities for enhancing sub-glacial imaging. The seismic profile imaged sediments ranging in thickness between 35 and 200 meters, and the underlying bedrock. Based on the geometry of the reflections we interpret three distinct seismic facies: a basal till layer, accreted sediments and re-worked till. The basal till and accreted sediments vary in thickness from less than 5 m to nearly 100 m thick and are interpreted as the zone of most recent deposition. A reflection polarity reversal observed at a low topographic region along the ice-sediment interface suggests the presence of liquid water spanning approximately 200 m along the profile. At NEEM we acquired a 5.8 km long-offset shot gather. Seismic imaging revealed two prominent reflections at the base of the ice. The upper reflection is interpreted at the base of ice - top of till interface whereas the lower reflection is interpreted as the base of till - top of bedrock. The thickness of the subglacial sediment section at NEEM is estimated to approximately 50 m using seismic imaging. The NEEM ice core drilled through the upper part of this section and ceased drilling before reaching bedrock.

  7. A comprehensive interpretation of the NEEM basal ice build-up using a multi parametric approach

    NASA Astrophysics Data System (ADS)

    Goossens, Thomas; Sapart, Celia Julia; Popp, Trevor; El Amri, Saïda; Tison, Jean-louis

    2015-04-01

    Basal ice is a common expression to describe debris-laden ice layers found close to the ice-bedrock interface under glaciers and ice sheets. The study of basal ice properties provides us with the unique opportunity of improving our understanding of subglacial environments and processes and refine ice sheet behaviour modelling. Here, we present and discuss the results of water stable isotopes (δ18O and δD), ice fabrics, debris weight and gas content of the basal part of the NEEM (North Eemian Ice Drilling Program) ice core. Below 2533.85 m deep, almost 10 m of basal debris-rich material were retrieved from the borehole. The situation at NEEM is different from the previously well-documented GRIP core where the basal ice corresponds to pre ice sheet ice overridden by the growing ice sheet. At NEEM, the basal debris-rich material presents δ18O values from -39.89 to -34.36 permil within the range of the above last 300 m of meteoric ice from -44.86 to -30.59 permil. The sequence is however composed of an alternation of three visually contrasting types of ice : clear ice with specks of particulate inclusions, stratified debris-rich layers, and ice containing dispersed debris. Using water stable isotopes (δ18O and δ D) signatures, each of these ice types are discriminated and clues are given for their conditions of formation and transformation processes. The proposed interpretation is then refined in the light of the other available parameters. While clear basal ice with specks corresponds to altered meteoric glacial ice, stratified debris-rich layer and ice containing dispersed debris present a melting/refreezing signature, somewhat blurred by mixing processes. Based on the identified origins of the different ice types, the present study proposes a first interpretative framework for the build-up of the NEEM basal ice sequence.

  8. Fabric measurement along the NEEM ice core, Greenland, and comparison with GRIP and NGRIP ice cores

    NASA Astrophysics Data System (ADS)

    Montagnat, M.; Azuma, N.; Dahl-Jensen, D.; Eichler, J.; Fujita, S.; Gillet-Chaulet, F.; Kipfstuhl, S.; Samyn, D.; Svensson, A.; Weikusat, I.

    2014-01-01

    Fabric (distribution of crystallographic orientations) profile along the full NEEM ice core, Greenland, is presented in this work. Data were measured in the field by an Automatic Ice Texture Analyzer every 10 m, from 33 m down to 2461 m depth. The fabric evolves from a slightly anisotropic fabric at the top, toward a strong single maximum at about 2300 m, which is typical of a deformation pattern mostly driven by uniaxial compression and simple shearing. A sharp increase in the fabric strengthening is observed at the Holocene to Wisconsin climatic transition. A similar strengthening, toward an anisotropic single maximum-type fabric, has been observed in several ice cores from Greenland and Antarctica, and can be attributed to a positive feedback between changes in ice viscosity at the climatic transition, and the impact of a shear component of stress. Centimeter scale abrupt texture (fabric and microstructure) variations are observed in the bottom part of the core. Their positions are in good agreement with the folding hypothesis used for a climatic reconstruction by Dahl-Jensen et al. (2013). Comparison is made to two others ice cores drilled along the same ridge; the GRIP ice core drilled at the summit of the ice sheet, and the NorthGRIP ice core, drilled 325 km to the NNW of the summit along the ridge, and 365 km upstream from NEEM. The fabric profile clearly reflects the increase in shear deformation when moving NW along the ridge from GRIP to NorthGRIP and NEEM. The difference in fabric profiles between NEEM and NorthGRIP also evidences a stronger lateral extension associated with a sharper ridge at NorthGRIP.

  9. Fabric measurement along the NEEM ice core, Greenland, and comparison with GRIP and NGRIP ice cores.

    NASA Astrophysics Data System (ADS)

    Montagnat, Maurine; Azuma, Nobuhiko; Dahl Jensen, Dorthe; Eichler, Jan; Fujita, Shuji; Gillet-Chaulet, Fabien; Kipfstuhl, Sepp; Samyn, Denis; Svensson, Anders; Weikusat, Ilka

    2014-05-01

    Fabric (distribution of crystallographic orientations) profile along the full NEEM ice core, Greenland, is presented in this work. Data were measured in the field by an Automatic Ice Texture Analyzer every 10 m, from 33 m down to 2461 m depth. The fabric evolves from a slightly anisotropic fabric at the top, toward a strong single maximum at about 2300 m, which is typical of a deformation pattern mostly driven by uniaxial compression and simple shearing. A sharp increase in the fabric strengthening is observed at the Holocene to Wisconsin climatic transition. A similar strengthening, toward an anisotropic single maximum-type fabric, has been observed in several ice cores from Greenland and Antarctica, and can be attributed to a positive feedback between changes in ice viscosity at the climatic transition, and the impact of a shear component of stress. Centimeter scale abrupt texture (fabric and microstructure) variations are observed in the bottom part of the core. Their positions are in good agreement with the folding hypothesis used for a climatic reconstruction by Dahl-Jensen and co authors (2013). Comparison is made to two others ice cores drilled along the same ridge; the GRIP ice core drilled at the summit of the ice sheet, and the NorthGRIP ice core, drilled 325 km to the NNW of the summit along the ridge, and 365 km upstream from NEEM. The fabric profile clearly reflects the increase in shear deformation when moving NW along the ridge from GRIP to NorthGRIP and NEEM. The difference in fabric profiles between NEEM and NorthGRIP also evidences a stronger lateral extension associated with a sharper ridge at NorthGRIP. References: Dahl-Jensen, D. and 120 co-authors. Eemian interglacial reconstructed from a Greenland folded ice core, Nature, 493, 489-493, 2013.

  10. [Effects of neem seed extracts on nitrogen use efficiency in two different soils].

    PubMed

    Zhang, Xiaoxiao; Shen, Qirong; Tan, Jiankang; Mao, Zesheng

    2002-11-01

    Incubation test and pot experiments were conducted with haplic luvisols and hydragric anthrosols to study the effects of neem seed extracts (N I, N II) on nitrification and immobilization of ammonium sulfate. N I could significantly inhibit the nitrification of N applied to the two soils. N II was effective in promoting the immobilization of NH4+(-)N. Pot experiments showed that N II could increase the use efficiency of chemical nitrogen significantly in fimic anthrosols. PMID:12624997

  11. THE INTERACTION OF AN ANTICHOLINESTERASE INSECTICIDE, DIAZINON, WITH A PYRETHROID INSECTICIDE, DELTAMETHRIN.

    EPA Science Inventory

    This present study explores the interaction of the toxicity induced by an organophosphorus insecticide, diazinon (diethyl 2-isopropyl-6methyl-4-pyrimidal phosphorothionate), with a pyrethroid insecticide, deltamethrin ((S)-a-cyano-3-phenoxybenzyl (1R,3R)-3-(2,2-dibromovinyl)-2,...

  12. Antioxidant enzyme changes in neem, pigeonpea and mulberry leaves in two stages of maturity

    PubMed Central

    Goud, Prashanth B.; Kachole, Manvendra S.

    2012-01-01

    Differential expression of antioxidant enzymes in various growth and differentiation stages has been documented in several plant species. We studied here, the difference in the levels of protein content and antioxidant enzymes activity at two stages of maturity, named young and mature in neem (Azadirachta indica A. Juss), pigeonpea (Cajanus cajan (L.) mill sp) and mulberry (Morus Alba L.) leaves. The results showed that detached neem and pigeonpea mature leaves possessed higher activities of catalase (CAT) and peroxidase (POD) and lower activities of polyphenol oxidase (PPO) and ascorbate peroxidase (APX) as compared with young leaves. However, glutathione reductase (GR) showed higher activity in mature leaves of neem, whereas no change in its activity was observed in pigeonpea. On the other hand, antioxidant enzymes in mulberry showed either positive (PPO) or negative (POD, GR, APX) correlation with the progression of leaf maturity. Apparently the trend of changes in antioxidant enzymes activity during leaf development is species-specific: their activity higher at mature stage in some plants and lower in others. PMID:22895104

  13. A study on the antimicrobial efficacy of RF oxygen plasma and neem extract treated cotton fabrics

    NASA Astrophysics Data System (ADS)

    Vaideki, K.; Jayakumar, S.; Thilagavathi, G.; Rajendran, R.

    2007-06-01

    The paper deals with a thorough investigation on the antimicrobial activity of RF oxygen plasma and Azadirachtin (neem extract) treated cotton fabric. The hydrophilicity of cotton fabric was found to improve when treated with RF oxygen plasma. The process parameters such as electrode gap, time of exposure and oxygen pressure have been varied to study their effect on improving the hydrophilicity of the cotton fabric. The static immersion test has been carried out to assess the hydrophilicity of the oxygen plasma treated samples and the process parameters were optimized based on these test results. The formation of carbonyl group during surface modification in the plasma treated sample was analysed using FTIR studies. The surface morphology has been studied using SEM micrographs. The antimicrobial activity was imparted to the RF oxygen plasma treated samples using methanolic extract of neem leaves containing Azadirachtin. The antimicrobial activity of these samples has been analysed and compared with the activity of the cotton fabric treated with neem extract alone. The investigation reveals that the surface modification due to RF oxygen plasma was found to increase the hydrophilicity and hence the antimicrobial activity of the cotton fabric when treated with Azadirachtin.

  14. Anthelmintic efficacy of crude neem (Azadirachta indica) leaf powder against bovine strongylosis.

    PubMed

    Jamra, Nirmala; Das, Giridhari; Singh, Priyanka; Haque, Manjurul

    2015-12-01

    The present study was conducted to evaluate the anthelmintic efficacy of crude neem (Azadirachta indica) leaf powder against strongyle infections in cattle. Based on copro-examination, 30 cattle positive for strongyle infection with at least 250 [eggs per gram (EPG) of faeces] were selected and grouped as A, B and C (10 animals/group). Group A and B were treated respectively with fendendazole and neem leaf powder @ 5 and 500 mg/kg body weight, whereas Group C served as infected untreated control. Faecal sample from each animal of these groups was examined on day 0, 7, 14 and 28 post treatments and EPG was determined. The result showed significant decrease (p < 0.05) in EPG in Group A and B after day 7 post treatment but there was no significant variation in terms of EPG in control group. Thus it can be concluded that crude neem leaf powder has anthelmintic property and it can further be studied to isolate the active component to produce herbal anthelminthics.

  15. Fire in ice: two millennia of Northern Hemisphere fire history from the Greenland NEEM ice core

    NASA Astrophysics Data System (ADS)

    Zennaro, P.; Kehrwald, N.; McConnell, J. R.; Schüpbach, S.; Maselli, O.; Marlon, J.; Vallelonga, P.; Leuenberger, D.; Zangrando, R.; Spolaor, A.; Borrotti, M.; Barbaro, E.; Gambaro, A.; Barbante, C.

    2014-02-01

    Biomass burning is a major source of greenhouse gases and influences regional to global climate. Pre-industrial fire-history records from black carbon, charcoal and other proxies provide baseline estimates of biomass burning at local to global scales, but there remains a need for broad-scale fire proxies that span millennia in order to understand the role of fire in the carbon cycle and climate system. We use the specific biomarker levoglucosan, and multi-source black carbon and ammonium concentrations to reconstruct fire activity from the North Greenland Eemian (NEEM) ice cores (77.49° N; 51.2° W, 2480 m a.s.l.) over the past 2000 years. Increases in boreal fire activity (1000-1300 CE and 1500-1700 CE) over multi-decadal timescales coincide with the most extensive central and northern Asian droughts of the past two millennia. The NEEM biomass burning tracers coincide with temperature changes throughout much of the past 2000 years except for during the extreme droughts, when precipitation changes are the dominant factor. Many of these multi-annual droughts are caused by monsoon failures, thus suggesting a connection between low and high latitude climate processes. North America is a primary source of biomass burning aerosols due to its relative proximity to the NEEM camp. During major fire events, however, isotopic analyses of dust, back-trajectories and links with levoglucosan peaks and regional drought reconstructions suggest that Siberia is also an important source of pyrogenic aerosols to Greenland.

  16. Phenolic acids in neem (Azadirachta indica): a major pre-existing secondary metabolites.

    PubMed

    Singh, U P; Maurya, S; Singh, D P

    2005-01-01

    High Performance Liquid Chromatographic (HPLC) analyses of various parts (fresh and dry bark of stem, mature and tender leaves, flower and different parts of fruit, i.e., raw and ripe fruit epicarp, mesocarp and seed) of neem (Azadirachta indica), which occupies an important place in socio-cultural-religious life in Indian communities, indicate that neem is rich in pre-existing secondary metabolites (phenolic acids). Dry bark showed only tannic acid but in fresh bark three phenolic acids were observed, i.e., gallic, tannic, and ferulic acids. In tender leaves only gallic and ferulic acids were detected, but the levels of these phenolic acids in mature leaves were about three times and fifty times greater, respectively. Flowers had only two phenolic acids in which gallic acid was maximum followed by chlorogenic acid. The level of phenolic acid was maximum in seeds followed by epicarp and pulp. In raw and ripe fruit seeds four phenolic acids were detected. Raw fruit seeds were rich in phenolic acids than ripe fruit seeds. Fruit epicarp was relatively richer than seed, seed pulp and flowers of the plants. Neem flowers were also rich in gallic and chlorogenic acids. PMID:16093234

  17. Effect of fungicides and insecticides on growth and enzyme activity of four cyanobacteria.

    PubMed

    Debnath, Manojit; Mandal, Narayan C; Ray, Samit

    2012-06-01

    Cyanobacterial populations introduced into crop fields as biofertilizer become non-target organisms for the pesticides and fungicides applied in the field. Effect of four commonly used pesticides viz. Bagalol, Mancozeb (fungicides), Thiodan and Phorate (insecticides) was studied on growth and different enzymes of four cyanobacterial species viz. Nostoc ellipsosporum, Scytonema simplex, Tolypothrix tenuis, and Westiellopsis prolifica. EC 50 concentration of each pesticide was determined for all cyanobacteria. Bagalol and Thiodan were found to be the most toxic. Both the fungicides and insecticides inhibited the activity of nitrogenase and glutamine synthetase (GS) at EC 50 concentration in all the four species studied. Bagalol incurred maximum inhibition of nitrogenase and GS activity on N. ellipsosporum and S. simplex while Thiodan and Phorate had maximum effect on T. tenuis, and W. prolifica. Mancozeb had lesser effect on all the above enzymes. One catabolic enzyme of carbohydrate metabolism, isocitrate dehydrogenase (ICDH) and one anabolic enzyme isocitrate lyase (ICL), which is related to glyoxylate pathway as well as gluconeogenesis, were also assayed. Cell free extracts of cyanobacteria treated with pesticides for 7 days show a drastic reduction of ICDH activity. ICL activity was induced in the organisms when treated with pesticides. PMID:23729894

  18. Fungitoxic and insecticidal plant polypeptides.

    PubMed

    Becker-Ritt, Arlete Beatriz; Carlini, Célia Regina

    2012-01-01

    According to the World Bank and FAO, the population grows worldwide and the poorest countries are expected to double their population within the next decades, reaching approximately 7.2 billion in 2015. Moreover, the food and financial crisis together with the global economic recession pushed the number of hungry and undernourished people in the world to unprecedented levels. The substitution of animal proteins by plant proteins in food and feed is a general trend because of the lower cost and better production efficiency. Pathogens and pests can reduce the crop yields up to 30%. In some places, the losses can reach 80% due to climate conditions, proliferation of insects, and fungal diseases. All together, the harvest and postharvest losses vary from 5% to 20% and depending on the commodity can be as high as 50%. Plants have a complex chemical armory for defense composed of low and high molecular mass compounds that can act over a variety of pests and pathogens, from micro-organisms to phytophagous insects or grazing animals. Among them, plant fungitoxic and insecticidal polypeptides represent promising alternatives to increase the supply of plant-derived proteins and tackle the hunger in a global scale. PMID:23193601

  19. Interactions of pyrethroid insecticides with GABA sub A and peripheral-type benzodiazepine receptors

    SciTech Connect

    Devaud, L.L.

    1988-01-01

    Pyrethroid insecticides are potent proconvulsants in the rat. All pyrethroids evincing proconvulsant activity elicited a similar 25-30% maximal reduction of seizure threshold. The Type II pyrethroids were the most potent proconvulsants with 1R{alpha}S, cis cypermethrin having an ED{sub 50} value of 6.3 nmol/kg. The proconvulsant activity of both Type I and Type II pyrenthroids was blocked by pretreatment with PK 11195, the peripheral-type benzodiazepine receptor (PTBR) antagonist. In contrast, phenytoin did not antagonize the proconvulsant activity of either deltamethrin or permethrin. Pyrethroids displaced the specific binding of ({sup 3}H)Ro5-4864 to rat brain membranes with a significant correlation between the log EC{sub 50} values for their activities as proconvulsants and the log IC{sub 50} values for their inhibition of ({sup 3}H)Ro5-4864 binding. Both Ro5-4864 and pyrethroid insecticides were found to influence specific ({sup 35}S)TBPS binding in a GABA-dependent manner. PK 11195 and the Type II pyrethroid, deltamethrin antagonized the Ro5-4864-induced modulation of ({sup 35}S)TBPS binding. Pyrethroid insecticides, Ro5-4864 and veratridine influenced GABA-gated {sup 36}Chloride influx. Moreover, the Type II pyrethroids elicited an increase in {sup 36}chloride influx in the absence of GABA-stimulation. Both of these actions were antagonized by PK 11195 and tetrodotoxin.

  20. Early post implantation contraceptive effects of a purified fraction of neem (Azadirachta indica) seeds, given orally in rats: possible mechanisms involved.

    PubMed

    Mukherjee, S; Garg, S; Talwar, G P

    1999-11-30

    Neem seed and leaf extracts have immunomodulators that induce cellular immune reactions. These aspects of neem were exploited in earlier studies, where the oral administration of the neem seed extracts in rodents and primates could completely abrogate pregnancy at an early post implantation stage. Complete restoration of fertility was observed in the animals treated in the subsequent cycles. For the purpose of using neem as a long term contraceptive, an activity guided fractionation, followed by identification and characterization of the biologically active fraction from neem seeds was carried out. Sequentially extracted fractions of neem seeds were tested orally at an early post implantation stage in rats. The hexane extract of the neem seeds was found to be biologically active and was the precursor for the final active fraction. The active fraction, identified as a mixture of six components, could completely abrogate pregnancy in rodents up to a concentration of 10%. No apparent toxic effects could be seen following treatment with the fraction. The treatment with the active fraction caused a specific activation of T lymphocyte cells of CD8+ subtype as well as phagocytic cells followed by elevation in cytokines gamma-interferon and TNF. The results of the present study show that a pure active fraction of neem seeds could be obtained for the purpose of early post implantation contraception when given orally, and its mechanism of action seems to be by activating cell mediated immune reactions. PMID:10617063

  1. The EC4 register of European clinical chemists and EC4 activities.

    PubMed

    Jansen, Rob T P

    2002-05-21

    The freedom of movement of people and goods within the European Union (EU) has a large impact for the member states. Particularly within health care it is important to recognize, or if necessary obtain, an adequate level of the quality of profession and practice, so that citizens know that health care is offered in their country at a level comparable to other countries. The importance of recognition also applies to laboratory medicine. European Communities Confederation of Clinical Chemistry (EC4) is the organization of societies for clinical chemistry and laboratory medicine in the EU. In Europe, health care develops in the direction where patients are treated in a health care chain environment. In this chain, patients move quickly from primary health institutes to secondary and tertiary institutes, and vice versa. This situation involves many health care workers including several laboratories. Diagnosis and therapy are now 'core business' of health care. Medical laboratories play an essential role in this. The broad spectrum of medical laboratory investigations make consultancy of medical laboratory specialists ever more important. The quality of both professionals and laboratories, as well as continuity of laboratory data within and between laboratories, are of utmost importance.EC4 is active in giving support to attain such quality. In most countries, this is the case at present. EC4 plays a central role in the Coordination of Automatic Recognition of Equivalence of Standards (CARE), if such a level exists or is achieved. Such CARE is focussed at three levels, the profession, quality of laboratories and calibration of laboratory data. The EC4 Register of European Clinical Chemists is open for colleagues educated in (bio)chemistry, pharmacy, biology as well as medicine, and trained according to the EC4 Syllabus. Equivalence of standards has been granted to national training schemes of 13 European Union countries. Since its opening in 1998, the number of

  2. In vitro bioactivity and antimicrobial tuning of bioactive glass nanoparticles added with neem (Azadirachta indica) leaf powder.

    PubMed

    Prabhu, M; Ruby Priscilla, S; Kavitha, K; Manivasakan, P; Rajendran, V; Kulandaivelu, P

    2014-01-01

    Silica and phosphate based bioactive glass nanoparticles (58SiO2-33CaO-9P2O5) with doping of neem (Azadirachta indica) leaf powder and silver nanoparticles were prepared and characterised. Bioactive glass nanoparticles were produced using sol-gel technique. In vitro bioactivity of the prepared samples was investigated using simulated body fluid. X-ray diffraction (XRD) pattern of prepared glass particles reveals amorphous phase and spherical morphology with a particle size of less than 50 nm. When compared to neem doped glass, better bioactivity was attained in silver doped glass through formation of hydroxyapatite layer on the surface, which was confirmed through XRD, Fourier transform infrared (FTIR), and scanning electron microscopy (SEM) analysis. However, neem leaf powder doped bioactive glass nanoparticles show good antimicrobial activity against Staphylococcus aureus and Escherichia coli and less bioactivity compared with silver doped glass particles. In addition, the biocompatibility of the prepared nanocomposites reveals better results for neem doped and silver doped glasses at lower concentration. Therefore, neem doped bioactive glass may act as a potent antimicrobial agent for preventing microbial infection in tissue engineering applications.

  3. [Potential of Metarhizium anisopliae and Beauveria bassiana isolates and neem oil to control the Aphid Lipaphis erysimi (Kalt.) (Hemiptera: Aphididae)].

    PubMed

    de Araujo, José M; Marques, Edmilson J; de Oliveira, José V

    2009-01-01

    This work aimed to determine the efficiency of the entomopathogenic fungi Metarhizium anisopliae and Beauveria bassiana to control the aphid Lipaphis erysimi (Kalt.) (Hemiptera: Aphididae) in kale Brassica oleracea var acephala D.C., as well as their compatibility with a neem oil formulation (Neemseto). Ten isolates of both fungi were tested and the most pathogenic ones were B. bassiana CG001 and M. anisopliae CG30 with 90% and 4.4 days, and 64% and 3.8 days of mortality and median lethal time, respectively. Bioassays with neem at concentrations of 0.5, 1.0 and 2.0% were done either by leaf discs dipping or spraying the aphids on the leaf discs. The neem spraying treatment at 2.0% provided 90% mortality. The use of B. bassiana isolate CG001 or M. anisopliae isolate CG30 with neem at 0.125, 0.25, and 0.5%, demonstrated that these isolates could have their spore viability or colony growth affected when exposed to neem concentrations higher than 0.25%. In absolute values, the isolates B. bassiana CG001 and M. anisopliae CG30 are the most virulent to L. erysimi, and could be utilized in the management of this pest. PMID:19768273

  4. In Vitro Bioactivity and Antimicrobial Tuning of Bioactive Glass Nanoparticles Added with Neem (Azadirachta indica) Leaf Powder

    PubMed Central

    Prabhu, M.; Ruby Priscilla, S.; Kavitha, K.; Manivasakan, P.; Rajendran, V.; Kulandaivelu, P.

    2014-01-01

    Silica and phosphate based bioactive glass nanoparticles (58SiO2-33CaO-9P2O5) with doping of neem (Azadirachta indica) leaf powder and silver nanoparticles were prepared and characterised. Bioactive glass nanoparticles were produced using sol-gel technique. In vitro bioactivity of the prepared samples was investigated using simulated body fluid. X-ray diffraction (XRD) pattern of prepared glass particles reveals amorphous phase and spherical morphology with a particle size of less than 50 nm. When compared to neem doped glass, better bioactivity was attained in silver doped glass through formation of hydroxyapatite layer on the surface, which was confirmed through XRD, Fourier transform infrared (FTIR), and scanning electron microscopy (SEM) analysis. However, neem leaf powder doped bioactive glass nanoparticles show good antimicrobial activity against Staphylococcus aureus and Escherichia coli and less bioactivity compared with silver doped glass particles. In addition, the biocompatibility of the prepared nanocomposites reveals better results for neem doped and silver doped glasses at lower concentration. Therefore, neem doped bioactive glass may act as a potent antimicrobial agent for preventing microbial infection in tissue engineering applications. PMID:25276834

  5. Summary of ECE presentations at EC-18

    SciTech Connect

    Taylor, G.

    2015-03-12

    There were nine ECE and one EBE presentation at EC-18. Four of the presentations were on various aspects of ECE on ITER. The ITER ECE diagnostic has entered an important detailed preliminary design phase and faces several design challenges in the next 2-3 years. Most of the other ECE presentations at the workshop were focused on applications of ECE diagnostics to plasma measurements, rather than improvements in technology, although it was apparent that heterodyne receiver technology continues to improve. CECE, ECE imaging and EBE imaging are increasingly providing valuable insights into plasma behavior that is important to understand if future burning plasma devices, such as ITER, FNSF and DEMO, are to be successful.

  6. Summary of ECE presentations at EC-18

    DOE PAGESBeta

    Taylor, G.

    2015-03-12

    There were nine ECE and one EBE presentation at EC-18. Four of the presentations were on various aspects of ECE on ITER. The ITER ECE diagnostic has entered an important detailed preliminary design phase and faces several design challenges in the next 2-3 years. Most of the other ECE presentations at the workshop were focused on applications of ECE diagnostics to plasma measurements, rather than improvements in technology, although it was apparent that heterodyne receiver technology continues to improve. CECE, ECE imaging and EBE imaging are increasingly providing valuable insights into plasma behavior that is important to understand if futuremore » burning plasma devices, such as ITER, FNSF and DEMO, are to be successful.« less

  7. Summary of ECE Presentations at EC-17

    NASA Astrophysics Data System (ADS)

    Austin, M. E.

    2012-09-01

    At the EC-17 workshop there were 12 presentations in the topic of diagnosing plasmas by measuring radiative emissions, mainly by ECE with one talk on EBW imaging. The number of ECE imaging systems on plasma devices has increased and new discoveries are being made from the expanded data set they provide. Technology continues to improve with some significant advances in receiver capabilities and clever designs for coupling to the plasma. A wide variety of ECE systems on many machines are providing crucial information on electron temperature and other plasma parameters, particularly on fluctuations related to MHD modes, their temporal and spatial structures. The ITER ECE system design is well along with the recent successful completion of the conceptual design review.

  8. Fire in Ice: Glacial-Interglacial biomass burning in the NEEM ice core

    NASA Astrophysics Data System (ADS)

    Zennaro, Piero; Kehrwald, Natalie; Zangrando, Roberta; Gambaro, Andrea; Barbante, Carlo

    2014-05-01

    Earth is an intrinsically flammable planet. Fire is a key Earth system process with a crucial role in biogeochemical cycles, affecting carbon cycle mechanisms, land-surface properties, atmospheric chemistry, aerosols and human activities. However, human activities may have also altered biomass burning for thousands of years, thus influencing the climate system. We analyse the specific marker levoglucosan to reconstruct past fire events in ice cores. Levoglucosan (1,6-anhydro-β-D-glucopyranose) is an organic compound that can be only released during the pyrolysis of cellulose at temperatures > 300°C. Levoglucosan is a major fire product in the fine fraction of woody vegetation combustion, can be transported over regional to global distances, and is deposited on the Greenland ice sheet. The NEEM, Greenland ice core (77 27'N, 51 3'W, 2454 masl) documents past fire activity changes from the present back to the penultimate interglacial, the Eemian. Here we present a fire activity reconstruction from both North American and Eurasian sources over the last 120,000 yrs based on levoglucosan signatures in the NEEM ice core. Biomass burning significantly increased over the boreal Northern Hemisphere since the last glacial, resulting in a maximum between 1.5 and 3.5 kyr BP yet decreasing from ~2 kyr BP until the present. Major climate parameters alone cannot explain the observed trend and thus it is not possible to rule out the hypothesis of early anthropogenic influences on fire activity. Over millennial timescales, temperature influences Arctic ice sheet extension and vegetation distribution at Northern Hemisphere high latitudes and may have altered the distance between NEEM and available fuel loads. During the last Glacial, the combination of dry and cold climate conditions, together with low boreal insolation and decreased atmospheric carbon dioxide levels may have also limited the production of available biomass. Diminished boreal forest extension and the southward

  9. Insecticide discovery: an evaluation and analysis.

    PubMed

    Sparks, Thomas C

    2013-09-01

    There is an on-going need for the discovery and development of new insecticides due to the loss of existing products through the development of resistance, the desire for products with more favorable environmental and toxicological profiles, shifting pest spectrums, and changing agricultural practices. Since 1960, the number of research-based companies in the US and Europe involved in the discovery of new insecticidal chemistries has been declining. In part this is a reflection of the increasing costs of the discovery and development of new pesticides. Likewise, the number of compounds that need to be screened for every product developed has, until recently, been climbing. In the past two decades the agrochemical industry has been able to develop a range of new products that have more favorable mammalian vs. insect selectivity. This review provides an analysis of the time required for the discovery, or more correctly the building process, for a wide range of insecticides developed during the last 60 years. An examination of the data around the time requirements for the discovery of products based on external patents, prior internal products, or entirely new chemistry provides some unexpected observations. In light of the increasing costs of discovery and development, coupled with fewer companies willing or able to make the investment, insecticide resistance management takes on greater importance as a means to preserve existing and new insecticides. PMID:25149229

  10. Meeting on insecticide-impregnated materials.

    PubMed

    1996-06-01

    Malaria causes considerable morbidity and mortality in Africa, killing 1.5-2.7 million people on the continent annually. A meeting on insecticide-impregnated materials was held at the World Health Organization (WHO) Regional Office for Africa (AFRO) during March 18-20, 1996, to promote the use of insecticide-impregnated materials by communities in Africa, review and discuss the results of recently conducted studies in the Africa Region on the use of insecticide-treated nets (ITNs) in malaria control, examine the best ways of implementing the wide-scale use of insecticide-impregnated materials under differing epidemiological and socioeconomic conditions, discuss major operational research priorities, and make recommendations for the promotion and wide use of insecticide-impregnated materials by malaria control programs and communities. The meeting was jointly organized by the WHO Division of Control of Tropical Diseases (CTD), the UNDP/World Bank/WHO Special Program for Research and Training in Tropical Diseases (TDR), and AFRO, and attended by experts, malaria control program managers, private sector representatives, nongovernmental organizations, and technical and scientific institutions. Conclusions and recommendations include the need to assess whether pregnant women could benefit from the use of ITNs. Elements of the successful implementation of sustained malaria control activities involving the use of ITNs are listed. Problems encountered in the large-scale implementation of ITNs in Africa should be addressed collaboratively at the regional and global levels, and coordinated by WHO.

  11. Insecticide discovery: an evaluation and analysis.

    PubMed

    Sparks, Thomas C

    2013-09-01

    There is an on-going need for the discovery and development of new insecticides due to the loss of existing products through the development of resistance, the desire for products with more favorable environmental and toxicological profiles, shifting pest spectrums, and changing agricultural practices. Since 1960, the number of research-based companies in the US and Europe involved in the discovery of new insecticidal chemistries has been declining. In part this is a reflection of the increasing costs of the discovery and development of new pesticides. Likewise, the number of compounds that need to be screened for every product developed has, until recently, been climbing. In the past two decades the agrochemical industry has been able to develop a range of new products that have more favorable mammalian vs. insect selectivity. This review provides an analysis of the time required for the discovery, or more correctly the building process, for a wide range of insecticides developed during the last 60 years. An examination of the data around the time requirements for the discovery of products based on external patents, prior internal products, or entirely new chemistry provides some unexpected observations. In light of the increasing costs of discovery and development, coupled with fewer companies willing or able to make the investment, insecticide resistance management takes on greater importance as a means to preserve existing and new insecticides.

  12. Neurobehavioral toxicology of pyrethroid insecticides

    SciTech Connect

    Crofton, K.M.

    1986-01-01

    Pyrethroid insecticides are classified as either Type I or Type II based upon in vivo toxic signs, and neurophysiological and biochemical data. Both axonal sodium channels and the ..gamma..-aminobutyric acid (GABA) receptor complex have been proposed as the major site of action of the Type II pyrethroids. This investigation characterized the behavior and biochemical effects of low dosages of pyrethroids in rats. Type I and II pyrethroids were tested for effects on figure-eight maze activity and the acoustic startle response (ASR). All compounds decreased figure-eight maze activity. Interactions of Type I and II pyrethroids with the three major binding sites on the GABA complex were determined in vivo. Radioligand binding experiments assessed in vitro interactions of pyrethroids with the three major GABA-complex binding sites. None of the pyrethroids competed for (/sup 3/H)-muscimol or (/sup 3/H)-flunitrazepam binding. Only Type II pyrethroids inhibited binding of (/sup 35/S)-t-butylbicyclophosphorothionate (TBPS) in cortical synaptosome preparations with K/sub i/ values of 5 to 10 ..mu..M. The (/sup 35/S)-TBPS data implicate the TBPS/picrotoxinin binding site in the mechanism of Type II pyrethroid toxicity. The results of these experiments support the classification of pyrethroids into two classes, and demonstrate the utility of the figure-eight maze and the ASR in studies to elucidate neurotoxic mechanisms. The interaction of the Type II pyrethroids is probably restricted to the TBPS/picrotoxinin binding domain on the GABA complex as shown by both the in vivo and in vitro studies.

  13. Ecotoxicity of neonicotinoid insecticides to bees.

    PubMed

    Decourtye, Axel; Devillers, James

    2010-01-01

    This chapter reviews the available data on the toxicity of neonicotinoid insecticides to bees that are the prominent and the most economically important group of pollinators worldwide. Classical and new methods developed to take into account the characteristics and different types of effects of the neonicotinoid insecticides to bees are described. The available toxicity results are critically analyzed. Thus, the nitro-substituted compounds (clothianidin, dinotefuran, imidacloprid and its metabolites, thiamethoxam, nitenpyram) appear the most toxic to bees. The cyano-substituted neonicotinoids seem to exhibit a much lower toxicity (acetamiprid and thiacloprid). The chapter ends with suggestions for additional studies aiming at better assess the hazard of this important insecticide family to bees.

  14. Inhibition of aflatoxin production by selected insecticides.

    PubMed

    Draughon, F A; Ayres, J C

    1981-04-01

    The insecticide naled completed inhibition production of aflatoxins B1, B2, G1, and G2 by and growth of Aspergillus parasiticus at a 100-ppm (100 microgram/ml) concentration. The insecticides dichlorvos, Landrin, pyrethrum, Sevin, malathion, and Diazinon significantly (P = 0.05) inhibited production of aflatoxins at a 100-ppm concentration. However, at a concentration of 10 ppm, significant inhibition in production of aflatoxins was found only with naled, dichlorvos, Sevin, Landrin, and pyrethrum. Dichlorvos, Landrin, Sevin, and naled inhibited growth of A. parasiticus by 28.9 , 18.9, 15.7, and 100%, respectively, at 100 ppm. Stimulation of growth was observed when diazinon was added to cultures. Aflatoxin B1 was most resistant to inhibition by insecticides, followed by G1, G2, and B2, respectively. PMID:6786222

  15. Residual insecticides and the problem of sorption

    PubMed Central

    Bertagna, P.

    1959-01-01

    Whereas laboratory investigations have elucidated the mechanism of sorption of residual insecticides and demonstrated that their persistency is determined by a number of physico-chemical factors and is therefore theoretically calculable, the variables encountered in the field may produce results in apparent conflict with those theoretically expected. Attempts to enhance persistency through the prevention of sorption, although promising, have so far not been fully successful. It is consequently also necessary to assess the residual effectiveness of insecticides, “effectiveness” here being viewed as a biological effect expressed in terms of the mosquito mortality produced. For this purpose bio-assay tests have been used, but with very variable results, and it is suggested that a study of the bio-assay technique itself is needed. This should be conducted in parallel with chemical determinations of the total amount of insecticide present both on and below the sprayed surface. PMID:13799942

  16. Operational use of neem oil as an alternative anopheline larvicide. Part B: Environmental impact and toxicological potential.

    PubMed

    Awad, O M

    2003-07-01

    This study was conducted to investigate the preliminary environmental and mammalian toxicology of neem oil, temephos and chlorpyriphos-methyl/fenitrothion. Culex pipiens, Daphnia magna and Gambusia affinis were used to study environmental impact. A high level of toxicity was observed, with slight differences between organisms. The emulsifiers individually also displayed toxicity towards the tested organisms. Up to 90 days daily oral crude neem oil treatment (5 g/kg body weight) of laboratory mice did not cause any significant changes in weekly body weight gain, nor in serum liver damage indicators, direct bilirubin or total bilirubin. Blood parameters of treated mice up to 90 days were not statistically different from those of control mice. Neem oil could be used as an environmentally friendly alternative to the traditional chemical anopheline larvicides. PMID:15748062

  17. Antimicrobial activity of herbal medicines (tulsi extract, neem extract) and chlorhexidine against Enterococcus faecalis in Endodontics: An in vitro study

    PubMed Central

    Chandrappa, Pradeep Muttagadur; Dupper, Akash; Tripathi, Pragya; Arroju, Ramakrishna; Sharma, Preeti; Sulochana, Konthoujam

    2015-01-01

    Background: Successful endodontic treatment depends on effective disinfection and complete sealing of root canal. Various medicaments are advised for disinfecting root canal, such as herbal and non-herbal medicaments. This study was done to assess the antimicrobial activity of herbal medicines (neem extract, tulsi extract) and chlorhexidine against Enterococcus faecalis in Endodontics. Materials and Methods: Agar diffusion method was used to evaluate the antimicrobial action of different medicines. Sixty samples were segregated into four groups with 15 samples in each: Group I: chlorhexidine 2%, Group II: neem extract, Group III: tulsi extract, and Group IV: distilled water. The inhibition zones against E. faecalis were recorded and statistically assessed using one-way analysis of variance (ANOVA) test (P < 0.05). Results: Significant antibacterial effect against E. faecalis was observed with chlorhexidine followed by neem extract and tulsi extract. Conclusion: Herbal medicines seemed to be effective against E. faecalis compared to 2% chlorhexidine gluconate. PMID:26942123

  18. Si pixel detectors in the detection of EC/EC decay

    SciTech Connect

    Jose, J. M.; Čermák, P.; Fajt, L.; Štekl, I.; Rukhadze, N. I.; Shitov, Yu. A.

    2015-08-17

    The SPT collaboration has been investigating the applicability of pixel detectors in the detection of two neutrino double electron capture (2νEC/EC) in{sup 106}Cd. The collaboration has proposed a Silicon Pixel Telescope (SPT) where a pair of Si pixel detectors with enriched Cd foil in the middle forms the detection unit. The Pixel detector gives spatial information along with energy of the particle, thus helps to identify and remove the background signals. Four units of SPT prototype (using 0.5 and 1 mm Si sensors) were fabricated and installed in the LSM underground laboratory, France. Recent progress in the SPT experiment and preliminary results from background measurements are presented.

  19. Antibacterial activity of guava (Psidium guajava L.) and Neem (Azadirachta indica A. Juss.) extracts against foodborne pathogens and spoilage bacteria.

    PubMed

    Mahfuzul Hoque, M D; Bari, M L; Inatsu, Y; Juneja, Vijay K; Kawamoto, S

    2007-01-01

    The antibacterial activity of guava (Psidium guajava) and neem (Azadirachta indica) extracts against 21 strains of foodborne pathogens were determined--Listeria monocytogenes (five strains), Staphylococcus aureus (four strains), Escherichia coli O157:H7 (six strains), Salmonella Enteritidis (four strains), Vibrio parahaemolyticus, and Bacillus cereus, and five food spoilage bacteria: Pseudomonas aeroginosa, P. putida, Alcaligenes faecalis, and Aeromonas hydrophila (two strains). Guava and neem extracts showed higher antimicrobial activity against Gram-positive bacteria compared to Gram-negative bacteria except for V. parahaemolyticus, P. aeroginosa, and A. hydrophila. None of the extracts showed antimicrobial activity against E. coli O157:H7 and Salmonella Enteritidis. The minimum inhibitory concentration (MIC) of ethanol extracts of guava showed the highest inhibition for L. monocytogenes JCM 7676 (0.1 mg/mL), S. aureus JCM 2151 (0.1 mg/mL), S. aureus JCM 2179 (0.1 mg/mL), and V. parahaemolyticus IFO 12711 (0.1 mg/mL) and the lowest inhibition for Alcaligenes faecalis IFO 12669, Aeromonas hydrophila NFRI 8282 (4.0 mg/mL), and A. hydrophila NFRI 8283 (4.0 mg/mL). The MIC of chloroform extracts of neem showed similar inhibition for L. monocytogenes ATCC 43256 (4.0 mg/mL) and L. monocytogenes ATCC 49594 (5.0 mg/mL). However, ethanol extracts of neem showed higher inhibition for S. aureus JCM 2151 (4.5 mg/mL) and S. aureus IFO 13276 (4.5 mg/mL) and the lower inhibition for other microorganisms (6.5 mg/mL). No significant effects of temperature and pH were found on guava and neem extracts against cocktails of L. monocytogenes and S. aureus. The results of the present study suggest that guava and neem extracts possess compounds containing antibacterial properties that can potentially be useful to control foodborne pathogens and spoilage organisms.

  20. Possible role of the Ec peptide of IGF-1Ec in cartilage repair

    PubMed Central

    Armakolas, Nikolaos; Dimakakos, Andreas; Armakolas, Athanasios; Antonopoulos, Athanasios; Koutsilieris, Michael

    2016-01-01

    The Ec peptide (PEc) of insulin-like growth factor 1 Ec (IGF-1Ec) induces human mesenchymal stem cell (hMSC) mobilization and activates extracellular signal-regulated kinase 1/2 (ERK 1/2) in various cells. The aim of the present study was to examine the effects of PEc on the mobilization and differentiation of hMSCs, as well as the possibility of its implementation in combination with transforming growth factor β1 (TGF-β1) for cartilage repair. The effects of the exogenous administration of PEc and TGF-β1, alone and in combination, on hMSCs were assessed using a trypan blue assay, reverse transcription-quantitative polymerase chain reaction, western blot analysis, Alcian blue staining, wound healing assays and migration/invasion assays. It was determined that PEc is involved in the differentiation process of hMSCs towards hyaline cartilage. Treatment of hMSCs with either PEc, TGF-β1 or both, demonstrated comparable cartilage matrix deposition. Furthermore, treatment with PEc in combination with TGF-β1 was associated with a significant increase in hMSC mobilization when compared with treatment with TGF-β1 or PEc alone (P<0.05). Thus, PEc appears to facilitate in vitro hMSC mobilization and differentiation towards chondrocytes, enhancing the role of TGF-β1. PMID:27571686

  1. Possible role of the Ec peptide of IGF‑1Ec in cartilage repair.

    PubMed

    Armakolas, Nikolaos; Dimakakos, Andreas; Armakolas, Athanasios; Antonopoulos, Athanasios; Koutsilieris, Michael

    2016-10-01

    The Ec peptide (PEc) of insulin-like growth factor 1 Ec (IGF-1Ec) induces human mesenchymal stem cell (hMSC) mobilization and activates extracellular signal‑regulated kinase 1/2 (ERK 1/2) in various cells. The aim of the present study was to examine the effects of PEc on the mobilization and differentiation of hMSCs, as well as the possibility of its implementation in combination with transforming growth factor β1 (TGF‑β1) for cartilage repair. The effects of the exogenous administration of PEc and TGF‑β1, alone and in combination, on hMSCs were assessed using a trypan blue assay, reverse transcription-quantitative polymerase chain reaction, western blot analysis, Alcian blue staining, wound healing assays and migration/invasion assays. It was determined that PEc is involved in the differentiation process of hMSCs towards hyaline cartilage. Treatment of hMSCs with either PEc, TGF‑β1 or both, demonstrated comparable cartilage matrix deposition. Furthermore, treatment with PEc in combination with TGF‑β1 was associated with a significant increase in hMSC mobilization when compared with treatment with TGF‑β1 or PEc alone (P<0.05). Thus, PEc appears to facilitate in vitro hMSC mobilization and differentiation towards chondrocytes, enhancing the role of TGF‑β1. PMID:27571686

  2. Toxicity of Neem Seed Oil against the Larvae of Boophilus decoloratus, A One-Host Tick In Cattle.

    PubMed

    Choudhury, M K

    2009-09-01

    The in vitro toxicity of neem seed oil (Azadirachta indica A. Juss, family: Meliaceae, Dogon yaro in Hausa language in Nigeria) was tested against the larvae of a one-host tick, Boophilus decoloratus (family: Ixodidae or hard tick, commonly known as blue tick) parasitic mainly to cattle generally found in savannas of tropical equatorial Africa. The 20, 40, 60, 80 and 100% concentrations of neem seed oil were found to kill all (100% mortality) the larvae after 27, 27, 27, 27 and 24 h respectively. PMID:20502579

  3. EC Driver - 41" Stroke Hydraulic Cylinder

    SciTech Connect

    Jaques, A.; /Fermilab

    1990-05-24

    It was decided to use a hydraulic cylinder resting on the floor of the argon spill trough in the EC carriage to drive the EC's motion on the center beam. Space was limited due to the spill bellows and their required support and containment system. The 0.0. of the cylinder had to be limited to 3 to 3-1/2 inches, maximum. The weight of a wet EC and carriage is estimated to be 320 tons. The rolling coefficient of friction of the Tychoway rollers chosen to guide the EC and carriage along the hardened centerbeam ways is claimed to be less than 0.0025. The driver will also need to overcome the forces produced by moving (rotating) the numerous bayonets located at the top of the cryostats in the many piping systems. These forces were conservatively estimated at 1000 lbs. The drive force required to overcome these forces was then calculated to be: 320(2,000) x 0.0025 + 1,000 = 2.600 lbs. (min. required). Due to the uncertainty in the actual roller coefficient of friction and the various unknowns in estimating the resistive forces contained in the piping and cabling systems attached to the cryostat, a conservative design factor of 5 was chosen. This should account for any uncertainty in our estimation of the minimum required drive force and also leaves us with a reserve to fall back on in case any unforeseen problems might arise. Thus the desired capacity of the driver was set at: (2,600) x 5 = 13,000 lbs. (design capacity). Assuming a 3 inch O.D. cylinder with a 1/2 inch wall (2 inch bore), we first analyzed a 1-3/8 inch diameter piston rod. Using Shigley & Mischke's 'Mechanical Engineering Design' (5th Ed.) and it's formulas for long columns with central loading, it was determined that a 1-3/8 inch diameter rod would not suffice, given our safety factor of 2. Increasing the piston rod diameter to 1-1/2 inches proved to be sufficient. The maximum allowable load came out to be approximately 17,000 lbs., which is greater than the 13,000 lbs. design capacity. With a 1-1/2 inch

  4. A genetic model of the effects of insecticide-treated bed nets on the evolution of insecticide-resistance

    PubMed Central

    Birget, Philip L. G.; Koella, Jacob C.

    2015-01-01

    Background and objectives: The evolution of insecticide-resistance in malaria vectors is emerging as a serious challenge for the control of malaria. Modelling the spread of insecticide-resistance is an essential tool to understand the evolutionary pressures and dynamics caused by the application of insecticides. Methodology: We developed a population-genetic model of the spread of insecticide-resistance in a population of Anopheles vectors in response to insecticides used either as adulticides (focussing on insecticide-treated bed nets (ITNs)) or as larvicides (either for the control of malaria or, as an inadvertent side-product, in agriculture). Results: We show that indoor use of insecticides leads to considerably less selection pressure than their use as larvicides, supporting the idea that most resistance of malaria vectors is due to the agricultural use of the insecticides that are also used for malaria control. The reasons for the relatively low selection pressure posed by adulticides are (i) that males are not affected by the ITNs and, in particular, (ii) that the insecticides are also repellents, keeping mosquitoes at bay from contacting the insecticide but also driving them to bite either people who do not use the insecticide or alternative hosts. Conclusion: We conclude by discussing the opposing public health benefits of high repellency at an epidemiological and an evolutionary timescale: whereas repellency is beneficial to delay the evolution of resistance, other models have shown that it decreases the population-level protection of the insecticide. PMID:26320183

  5. Morphological effects of neem (Azadirachta indica A. Juss) seed oil with known azadirachtin concentrations on the oocytes of semi-engorged Rhipicephalus sanguineus ticks (Acari: Ixodidae).

    PubMed

    Remedio, R N; Nunes, P H; Anholeto, L A; Oliveira, P R; Camargo-Mathias, M I

    2015-02-01

    The concern about the harmful effects caused by synthetic pesticides has led to the search for safe and ecological alternatives for pest control. In this context, the neem tree (Azadirachta indica) stands out due to its repellent properties and effects on various arthropods, including ticks. For this reason, this study aimed to demonstrate the potential of neem as a control method for Rhipicephalus sanguineus ticks, important vectors of diseases in the veterinary point of view. For this, R. sanguineus semi-engorged females were subjected to treatment with neem seed oil enriched with azadirachtin, its main compound, and ovaries were assessed by means of morphological techniques in conventional light microscopy, confocal laser scanning microscopy, and transmission electron microscopy. Neem demonstrated a clear dose-dependent effect in the analyzed samples. The observed oocytes presented, especially in the groups treated with higher concentrations of neem oil, obvious signs of cytoplasmic disorganization, cellular vacuolization, nuclear and nucleolar irregularity, dilation in mitochondrial cristae, alterations in mitochondrial matrix, and swelling of rough endoplasmic reticulum. Intracellular microorganisms were observed in all analyzed groups, reinforcing the importance of ticks in the transmission of pathogens. A greater quantity of microorganisms was noted as the concentration of neem increased, indicating that the damaged oocytes may be more susceptible for their development. Such morphological alterations may promote future damages in reproductive performance of these animals and demonstrate the potential of neem seed oil for the control of R. sanguineus ticks, paving the way for new, cheaper, and safer methods of control. PMID:25346198

  6. Morphological effects of neem (Azadirachta indica A. Juss) seed oil with known azadirachtin concentrations on the oocytes of semi-engorged Rhipicephalus sanguineus ticks (Acari: Ixodidae).

    PubMed

    Remedio, R N; Nunes, P H; Anholeto, L A; Oliveira, P R; Camargo-Mathias, M I

    2015-02-01

    The concern about the harmful effects caused by synthetic pesticides has led to the search for safe and ecological alternatives for pest control. In this context, the neem tree (Azadirachta indica) stands out due to its repellent properties and effects on various arthropods, including ticks. For this reason, this study aimed to demonstrate the potential of neem as a control method for Rhipicephalus sanguineus ticks, important vectors of diseases in the veterinary point of view. For this, R. sanguineus semi-engorged females were subjected to treatment with neem seed oil enriched with azadirachtin, its main compound, and ovaries were assessed by means of morphological techniques in conventional light microscopy, confocal laser scanning microscopy, and transmission electron microscopy. Neem demonstrated a clear dose-dependent effect in the analyzed samples. The observed oocytes presented, especially in the groups treated with higher concentrations of neem oil, obvious signs of cytoplasmic disorganization, cellular vacuolization, nuclear and nucleolar irregularity, dilation in mitochondrial cristae, alterations in mitochondrial matrix, and swelling of rough endoplasmic reticulum. Intracellular microorganisms were observed in all analyzed groups, reinforcing the importance of ticks in the transmission of pathogens. A greater quantity of microorganisms was noted as the concentration of neem increased, indicating that the damaged oocytes may be more susceptible for their development. Such morphological alterations may promote future damages in reproductive performance of these animals and demonstrate the potential of neem seed oil for the control of R. sanguineus ticks, paving the way for new, cheaper, and safer methods of control.

  7. Azadirachta indica (neem) leaf dietary effects on the immunity response and disease resistance of Asian seabass, Lates calcarifer challenged with Vibrio harveyi.

    PubMed

    Talpur, Allah Dad; Ikhwanuddin, Mhd

    2013-01-01

    The present study was aimed to address the possible evaluation of Azadirachta indica (neem) leaf-supplemented diets on innate immune response in Asian seabass, Lates calcarifer fingerlings against Vibrio harveyi infection. Fish were fed for two weeks diets containing six graded levels of neem leaf at 0 g, 1 g, 2 g, 3 g, 4 g and 5 g per kg feed. Fish fed neem leaf-supplemented diet displayed significant differences (p < 0.05) in weight gain, specific growth rate (SGR) and feed conversion ratio (FCR) compared to the control group fed without neem leaf-supplemented diet. Various innate immune parameters were examined pre-challenge and post-challenge. Fish was injected intraperitoneally with a lethal dose of V. harveyi containing 10(8) cells mL(-1). Supplementation of neem leaf diet significantly increased phagocytic activity, superoxide anion production, serum lysozyme, serum bactericidal activity, serum anti-protease activity throughout the experimental period when compared with the control group. Dietary doses of neem leaf diet significantly influenced the immune parameters, haematological parameters and blood biochemical indices of treated fish. The results suggested that fish fed neem leaf-supplemented diet improved the immune system and increased survival rate in L. calcarifer fingerlings against V. harveyi infection.

  8. Effects of pyrethroid insecticides in urban runoff on Chinook salmon, steelhead trout, and their invertebrate prey.

    PubMed

    Weston, Donald P; Schlenk, Daniel; Riar, Navneet; Lydy, Michael J; Brooks, Marjorie L

    2015-03-01

    Pyrethroid insecticides can affect salmonids either indirectly through toxicity to their prey or directly by toxicity to the fish themselves. In support of a study on pyrethroid impacts to Chinook salmon and steelhead trout in the American River (Sacramento, California, USA), 96-h median effective concentration (EC50) and median lethal concentration (LC50) values for the pyrethroid bifenthrin were determined for taxa not traditionally used for toxicity testing but of interest as salmonid prey, including a chironomid, caddisflies, mayflies, and stoneflies. A laboratory was constructed on the banks of the American River to expose macroinvertebrates, Chinook salmon, and steelhead trout to flow-through river water containing urban runoff during storm events. Bifenthrin from urban runoff was found in river water following 5 rain events, reaching 14.6 ng/L. Mortality to the exposed salmonids was not observed, and sublethal effects were not seen in vitellogenin or sex steroid levels. Indirect effects via toxicity to salmonid prey are possible. Mortality to Hyalella azteca, a potential prey, was observed in every event tested, and peak bifenthrin concentrations were comparable to the 96-h EC50 of the caddisfly, Hydropsyche sp., the most important prey species on a biomass basis for American River Chinook salmon. The other invertebrates tested had EC50s exceeding bifenthrin concentrations seen in the American River, though could potentially be at risk at concentrations previously reported in smaller urban tributaries. Environ Toxicol Chem 2015;34:649-657. © 2014 SETAC. PMID:25545717

  9. Insecticide Resistance: Challenge to Pest Management and Basic Research

    NASA Astrophysics Data System (ADS)

    Brattsten, L. B.; Holyoke, C. W.; Leeper, J. R.; Raffa, K. F.

    1986-03-01

    The agricultural use of synthetic insecticides usually protects crops but imposes strong selection pressures that can result in the development of resistance. The most important resistance mechanisms are enhancement of the capacity to metabolically detoxify insecticides and alterations in target sites that prevent insecticides from binding to them. Insect control methods must incorporate strategies to minimize resistance development and preserve the utility of the insecticides. The most promising approach, integrated pest management, includes the use of chemical insecticides in combination with improved cultural and biologically based techniques.

  10. Insecticidal sugar baits for adult biting midges

    Technology Transfer Automated Retrieval System (TEKTRAN)

    One of the latest trends in mosquito control is the use of insecticidal sugar baits (ISBs) to reduce adult mosquito populations. Tested here is the ability of ISB’s to knock-down the biting midge, Culicoides sonorensis, a disease vector of bluetongue, epizootic hemorrhagic disease, and vesicular sto...

  11. The 1975 Insecticide, Herbicide, Fungicide Quick Guide.

    ERIC Educational Resources Information Center

    Page, Bill G.; Thomson, W. T.

    This is a quick guide for choosing a chemical to use to control a certain pest on a specific crop. Information in the book was obtained from manufacturers' labels and from the USDA and FDA pesticide summary. The book is divided into four parts: (1) insecticides, (2) herbicides, (3) fungicides, and (4) conversion tables. Each of the first three…

  12. Newer insecticides for plant virus disease management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Effective management of insect and mite vectors of plant pathogens is of crucial importance to minimizing vector-borne diseases in crops. Insecticides play an important role in managing vector populations by reducing the number of individuals that can acquire and transmit a virus, thereby potentiall...

  13. DEVELOPMENTAL NEUROTOXICITY OF PYRETHROID INSECTICIDES: CRITICAL REVIEW.

    EPA Science Inventory

    Pyrethroids are widely utilized insecticides whose primary action is the disruption of voltage-sensitive sodium channels (VSSC). Although these compounds have been in use for over 30 years and their acute neurotoxicity has been well characterized, there is considerably less info...

  14. Assimilation of Sonic Velocity and Thin Section Measurements from the NEEM Ice Core

    NASA Astrophysics Data System (ADS)

    Hay, Michael; Pettit, Erin; Kluskiewicz, Dan; Waddington, Edwin

    2016-04-01

    We examine the measurement of crystal orientation fabric (COF) in ice cores using thin sections and sound-wave velocities, focusing on the NEEM core in Greenland. Ice crystals have substantial plastic anisotropy, with shear orthogonal to the crystallographic c-axis occuring far more easily than deformation in other orientations. Due to strain-induced grain-rotation, COFs can become highly anisotropic, resulting in bulk anisotropic flow. Thin-section measurements taken from ice cores allow sampling of the crystal fabric distribution. Thin-section measurements, however, suffer from sampling error, as they sample a small amount of ice, usually on the order of a hundred grans. They are typically only taken at intervals of several meters, which means that meter-scale variations in crystal fabric are difficult to capture. Measuring sonic velocities in ice cores provides an alternate method of determining crystal fabric. The speed of vertical compression waves is affected by the vertical clustering of c-axes, but is insensitive to azimuthal fabric anisotropy. By measuring splitting between the fast and slow shear-wave directions, information on the azimuthal distribution of orientations can be captured. Sonic-velocity measurements cannot capture detailed information on the orientation distribution of the COF, but they complement thin-section measurements with several advantages. Sonic-logging measurements can be taken at very short intervals, eliminating spatial gaps. In addition, sonic logging samples a large volume of ice with each measurement, reducing sampling error. Our logging tool has a depth resolution of around 3m/s, and can measure velocity features on the order of 1m/s. Here, we show the results of compression-wave measurements at NEEM. We also combine sonic-velocity measurements and thin-section measurements to produce a more accurate and spatially-complete representation of ice-crystal orientations in the vicinity of the NEEM core.

  15. Surface elevation change artifact at the NEEM ice core drilling site, North Greenland.

    NASA Astrophysics Data System (ADS)

    Berg Larsen, Lars; Schøtt Hvidberg, Christine; Dahl-Jensen, Dorthe; Lilja Buchardt, Susanne

    2014-05-01

    The NEEM deep drilling site (77.45°N 51.06°W) is located at the main ice divide in North Greenland. For the ice core drilling project, a number of buildings was erected and left on the snow surface during the five-year project period. The structures created snowdrifts that formed accordingly to the predominant wind direction on the lee side on the buildings and the overwintering cargo. To get access to the buildings, the snowdrifts and the accumulated snow were removed and the surface in the camp was leveled with heavy machinery each summer. In the camp a GPS reference pole was placed as a part of the NEEM strain net, 12 poles placed in three diamonds at distances of 2,5 km, 7,5 km and 25 km they were all measured with high precision GPS every year. Around the reference pole, a 1 km x 1 km grid with a spacing of 100 m was measured with differential GPS each year. In this work, we present results from the GPS surface topography measurements in and around the campsite. The mapping of the topography in and around the campsite shows how the snowdrifts evolve and are the reason for the lift of the camp site area. The accumulated snowdrifts are compared to the dominant wind directions from year to year. The annual snow accumulation at the NEEM site is 0.60 m. The reference pole in the camp indicates an additional snow accumulation of 0.50 m per year caused by collected drifting snow. The surface topography mapping shows that this artificially elevated surface extends up to several kilometers out in the terrain. This could have possible implications on other glaciological and geophysical measurements in the area i.e. pit and snow accumulation studies.

  16. Oviposition and olfaction responses of Aedes aegypti mosquitoes to insecticides.

    PubMed

    Canyon, D V; Muller, R

    2013-12-01

    Insecticide applications are not particularly effective on Aedes aegypti mosquitoes which has been attributed to their 'closet' behaviour, or ability to rest in places that remain unexposed to insecticides. Some researchers have suggested that insecticides repel mosquitoes, which would result in less exposure and increased dispersal. If repellence due to insecticides is a fact, acquiring a vector-borne disease, such as dengue, could legitimately be attributed to local vector control efforts and this would lead to restitution claims. This study thus investigated the effect of insecticide presence on mosquito behaviour indirectly via oviposition and directly via olfactory response. In all experiments, oviposition in each insecticide compared to its water and ethanol controls was not significantly different. This indicates that Ae. aegypti mosquitoes are not affected by insecticide presence and that increased dispersal is unlikely to be caused by vector control spraying.

  17. ECS Special Education Handbook: 2008/2009 School Year

    ERIC Educational Resources Information Center

    Alberta Education, 2008

    2008-01-01

    This handbook explains basic funding requirements for Early Childhood Services (ECS) and how to complete application forms required for the services. It also outlines the age of eligibility for funding for all types of ECS programming. The handbook explains other funding that is provided for children identified with mild to moderate…

  18. Status of Europe's contribution to the ITER EC system

    NASA Astrophysics Data System (ADS)

    Albajar, F.; Aiello, G.; Alberti, S.; Arnold, F.; Avramidis, K.; Bader, M.; Batista, R.; Bertizzolo, R.; Bonicelli, T.; Braunmueller, F.; Brescan, C.; Bruschi, A.; von Burg, B.; Camino, K.; Carannante, G.; Casarin, V.; Castillo, A.; Cauvard, F.; Cavalieri, C.; Cavinato, M.; Chavan, R.; Chelis, J.; Cismondi, F.; Combescure, D.; Darbos, C.; Farina, D.; Fasel, D.; Figini, L.; Gagliardi, M.; Gandini, F.; Gantenbein, G.; Gassmann, T.; Gessner, R.; Goodman, T. P.; Gracia, V.; Grossetti, G.; Heemskerk, C.; Henderson, M.; Hermann, V.; Hogge, J. P.; Illy, S.; Ioannidis, Z.; Jelonnek, J.; Jin, J.; Kasparek, W.; Koning, J.; Krause, A. S.; Landis, J. D.; Latsas, G.; Li, F.; Mazzocchi, F.; Meier, A.; Moro, A.; Nousiainen, R.; Purohit, D.; Nowak, S.; Omori, T.; van Oosterhout, J.; Pacheco, J.; Pagonakis, I.; Platania, P.; Poli, E.; Preis, A. K.; Ronden, D.; Rozier, Y.; Rzesnicki, T.; Saibene, G.; Sanchez, F.; Sartori, F.; Sauter, O.; Scherer, T.; Schlatter, C.; Schreck, S.; Serikov, A.; Siravo, U.; Sozzi, C.; Spaeh, P.; Spichiger, A.; Strauss, D.; Takahashi, K.; Thumm, M.; Tigelis, I.; Vaccaro, A.; Vomvoridis, J.; Tran, M. Q.; Weinhorst, B.

    2015-03-01

    The electron cyclotron (EC) system of ITER for the initial configuration is designed to provide 20MW of RF power into the plasma during 3600s and a duty cycle of up to 25% for heating and (co and counter) non-inductive current drive, also used to control the MHD plasma instabilities. The EC system is being procured by 5 domestic agencies plus the ITER Organization (IO). F4E has the largest fraction of the EC procurements, which includes 8 high voltage power supplies (HVPS), 6 gyrotrons, the ex-vessel waveguides (includes isolation valves and diamond windows) for all launchers, 4 upper launchers and the main control system. F4E is working with IO to improve the overall design of the EC system by integrating consolidated technological advances, simplifying the interfaces, and doing global engineering analysis and assessments of EC heating and current drive physics and technology capabilities. Examples are the optimization of the HVPS and gyrotron requirements and performance relative to power modulation for MHD control, common qualification programs for diamond window procurements, assessment of the EC grounding system, and the optimization of the launcher steering angles for improved EC access. Here we provide an update on the status of Europe's contribution to the ITER EC system, and a summary of the global activities underway by F4E in collaboration with IO for the optimization of the subsystems.

  19. Experimental hut comparisons of nets treated with carbamate or pyrethroid insecticides, washed or unwashed, against pyrethroid-resistant mosquitoes.

    PubMed

    Asidi, A N; N'Guessan, R; Hutchinson, R A; Traoré-Lamizana, M; Carnevale, P; Curtis, C F

    2004-06-01

    The efficacy against mosquitoes (Diptera: Culicidae) of a bednet treated with carbamate insecticide [carbosulfan capsule suspension (CS) 200 mg/m(2)] was compared with four types of pyrethroid-treated nets in veranda-trap huts at Yaokoffikro near Bouaké, Côte d'Ivoire, where the malaria vector Anopheles gambiae Giles carries the kdr gene (conferring pyrethroid resistance) at high frequency and Culex quinquefasciatus Say is also pyrethroid resistant. Pyrethroids compared were lambdacyhalothrin CS 18 mg/m(2), alphacypermethrin water dispersible granules (WG) 20 mg/m(2), deltamethrin 50 mg/m(2) (Permanet) and permethrin emulsifiable concentrate (EC) 500 mg/m(2). Insecticidal power and personal protection from mosquito bites were assessed before and after the nets were used for 8 months and hand washed five times in cold soapy water. Before washing, all treatments except permethrin significantly reduced blood-feeding and all had significant insecticidal activity against An. gambiae. The carbosulfan net gave significantly higher killing of An. gambiae than all pyrethroid treatments except the Permanet. Against Culex spp., carbosulfan was more insecticidal and gave a significantly better protective effect than any of the pyrethroid treatments. After washing, treated nets retained various degrees of efficacy against both mosquito genera - but least for the carbosulfan net. Washed nets with three types of pyrethroid treatment (alphacypermethrin, lambdacyhalothrin, permethrin) gave significantly higher mortality rates of Culex than in huts with the same pyrethroid-treated nets before washing. After five washes, the Permanet, which is sold as a long-lasting insecticidal product, performed no better than the other nets in our experimental conditions.

  20. Protective Effect of Aqueous Crude Extract of Neem (Azadirachta indica) Leaves on Plasmodium berghei-Induced Renal Damage in Mice

    PubMed Central

    Somsak, Voravuth; Chachiyo, Sukanya; Jaihan, Ubonwan; Nakinchat, Somrudee

    2015-01-01

    Malaria is a major public health problem in the world because it can cause of death in patients. Malaria-associated renal injury is associated with 45% of mortality in adult patients hospitalized with severe form of the disease. Therefore, new plant extracts to protect against renal injury induced by malaria infection are urgently needed. In this study, we investigated the protective effect of aqueous crude extract of Azadirachta indica (neem) leaves on renal injury induced by Plasmodium berghei ANKA infection in mice. ICR mice were injected intraperitoneally with 1 × 107 parasitized erythrocytes of PbANKA, and neem extracts (500, 1,000, and 2,000 mg/kg) were given orally for 4 consecutive days. Plasma blood urea nitrogen (BUN) and creatinine levels were subsequently measured. Malaria-induced renal injury was evidenced as marked increases of BUN and creatinine levels. However, the oral administration of neem leaf extract to PbANKA infected mice for 4 days brought back BUN and creatinine levels to near normalcy, and the highest activity was observed at doses of 1,000 and 2,000 mg/kg. Additionally, no toxic effects were found in normal mice treated with this extract. Hence, neem leaf extract can be considered a potential candidate for protection against renal injury induced by malaria. PMID:26379714

  1. Toxicity of neem pesticides on a fresh water loach, Lepidocephalichthys guntea (Hamilton Buchanan) of Darjeeling district in West Bengal.

    PubMed

    Mondal, Debashri; Barat, Sudip; Mukhopadhyay, M K

    2007-01-01

    Static renewal bioassay tests were conducted to evaluate the acute toxicity of two neem based biopesticides, applied widely on tea plantation namely, Nimbecidine and Neem Gold either separately as well as, in combination to the fingerlings (mean body length- 4.46 +/- 0.15 cm; mean body weight- 0.49 +/- 0.15g) of a fresh water loach, Lepidocephalichthys guntea (Hamilton Buchanan) acclimatized to laboratory conditions prior to experiment. The 96 hours LC50 values for Nimbecidine and Neem Gold and the combination of the two were 0.0135 mgl(-1), 0.0525mgl(-1) and 0.0396 mgl(-1), respectively. The regular water quality analysis showed, that with increasing doses of biopesticides, dissolved oxygen level was lower and other parameters like pH, free carbon dioxide, total alkalinity total hardness, chloride ions of water increased. The fish under toxicity stress suffered several abnormalities such as erratic and rapid movement, body imbalance and surface floating responding proportionately to the increase in concentrations of the toxicant biopesticides. The 96 hours LC50 values proved Nimbecidine more toxic than Neem Gold and the combination of the two biopesticides.

  2. Protective Effect of Aqueous Crude Extract of Neem (Azadirachta indica) Leaves on Plasmodium berghei-Induced Renal Damage in Mice.

    PubMed

    Somsak, Voravuth; Chachiyo, Sukanya; Jaihan, Ubonwan; Nakinchat, Somrudee

    2015-01-01

    Malaria is a major public health problem in the world because it can cause of death in patients. Malaria-associated renal injury is associated with 45% of mortality in adult patients hospitalized with severe form of the disease. Therefore, new plant extracts to protect against renal injury induced by malaria infection are urgently needed. In this study, we investigated the protective effect of aqueous crude extract of Azadirachta indica (neem) leaves on renal injury induced by Plasmodium berghei ANKA infection in mice. ICR mice were injected intraperitoneally with 1 × 10(7) parasitized erythrocytes of PbANKA, and neem extracts (500, 1,000, and 2,000 mg/kg) were given orally for 4 consecutive days. Plasma blood urea nitrogen (BUN) and creatinine levels were subsequently measured. Malaria-induced renal injury was evidenced as marked increases of BUN and creatinine levels. However, the oral administration of neem leaf extract to PbANKA infected mice for 4 days brought back BUN and creatinine levels to near normalcy, and the highest activity was observed at doses of 1,000 and 2,000 mg/kg. Additionally, no toxic effects were found in normal mice treated with this extract. Hence, neem leaf extract can be considered a potential candidate for protection against renal injury induced by malaria.

  3. The NEEM Stable Water Isotope Profile - new evidence of past Greenland Ice Sheet responses to Climate Change

    NASA Astrophysics Data System (ADS)

    Vinther, Bo; Neem Isotope Consortium, The

    2013-04-01

    Deep ice cores from the Greenland ice sheet are providing an ever expanding set of records of past Greenland climatic conditions throughout the last glacial-interglacial cycle. Stable water isotope records from the ice cores have been influenced both by changing climatic conditions and by any elevation change that has happened at the ice core drill site. The new NEEM ice core drilled in NW Greenland is located on an ice divide connected to the very summit of the Greenland ice sheet. In fact four ice cores have now been drilled on this divide: GRIP (at the summit), NGRIP some 300km north of GRIP, NEEM some 350km north-west of NGRIP and Camp Century some 250 km west of NEEM. All four ice cores contain both the entire Holocene and most of the glacial period undisturbed. The new NEEM δ18O record therefore completes a four core transect along this ice divide. The four δ18O records from the cores all span more than 100,000 years. From an inter-comparison of these records a picture emerges of a dynamic Greenland ice sheet shrinking and expanding in direct response to changing climatic conditions. Indeed the glacial Greenland ice sheet must have covered vast areas that are now ice free, expanding far out on the continental shelf and forming an ice ridge all the way to the Canadian high arctic. During both the transition period and the early Holocene, the Greenland ice sheet retreated dramatically.

  4. Toxicity of neem pesticides on a fresh water loach, Lepidocephalichthys guntea (Hamilton Buchanan) of Darjeeling district in West Bengal.

    PubMed

    Mondal, Debashri; Barat, Sudip; Mukhopadhyay, M K

    2007-01-01

    Static renewal bioassay tests were conducted to evaluate the acute toxicity of two neem based biopesticides, applied widely on tea plantation namely, Nimbecidine and Neem Gold either separately as well as, in combination to the fingerlings (mean body length- 4.46 +/- 0.15 cm; mean body weight- 0.49 +/- 0.15g) of a fresh water loach, Lepidocephalichthys guntea (Hamilton Buchanan) acclimatized to laboratory conditions prior to experiment. The 96 hours LC50 values for Nimbecidine and Neem Gold and the combination of the two were 0.0135 mgl(-1), 0.0525mgl(-1) and 0.0396 mgl(-1), respectively. The regular water quality analysis showed, that with increasing doses of biopesticides, dissolved oxygen level was lower and other parameters like pH, free carbon dioxide, total alkalinity total hardness, chloride ions of water increased. The fish under toxicity stress suffered several abnormalities such as erratic and rapid movement, body imbalance and surface floating responding proportionately to the increase in concentrations of the toxicant biopesticides. The 96 hours LC50 values proved Nimbecidine more toxic than Neem Gold and the combination of the two biopesticides. PMID:17717997

  5. NP1EC Degradation Pathways Under Oxic and Microxic Conditions

    SciTech Connect

    Montgomery-Brown, John; Li, Yongmei; Ding, Wang-Hsien; Mong, Gary M.; Campbell, James A.; Reinhard, Martin

    2008-03-22

    The degradation pathway of nonylphenol ethoxyacetic acid (NP1EC) and the conditions favoring CAP1EC formation were studied in aerobic microcosms constructed with soil from the Mesa soil aquifer treatment (SAT) facility (Arizona, USA) and pristine sediments from Coyote Creek (California, USA). In the Mesa microcosms, para-NP1EC was transformed to para-NP, before being rapidly transformed to nonyl alcohols via ipso-hydroxylation. While the formation of NP from APEMs has been observed by several researchers under anaerobic conditions, this is the first time the transient formation of NP from APEMs has been observed under aerobic conditions. Unlike the Mesa microcosms, large quantities of CAP1ECs were observed in the Coyote Creek microcosms. Initially, CA8P1ECs were the dominant metabolites, but as biodegradation continued, CA6P1ECs became the dominant metabolites. Compared to the CA8P1ECs, the number of CA6P1ECs peaks observed was small (<6) even though their concentrations were high. This suggests that several CA8P1ECs are degraded to only a few CA6P1EC isomers (i.e., the degradation pathway converges) or that some CA6P1EC metabolites are significantly more recalcitrant than others. The different biodegradation pathways observed in the Mesa and Coyote Creek microcosms result from the limited availability of dissolved oxygen in the Coyote Creek microcosms. In both sets of microcosms, the ortho isomers were transformed more slowly than the para isomers and in the Coyote Creek microcosms several ortho-CAP1ECs were observed. In addition, several unknown metabolites were observed in the Coyote Creek microcosms that were not seen in the abiotic or Mesa microcosms; these metabolites appear to be CAP1EC metabolites, have a -CH2-C6H4- fragment, and contain one carboxylic acid. Nitro-nonylphenol was observed in the Mesa microcosms, however, further experimentation illustrated that it was the product of an abiotic reaction between nitrite and nonylphenol under acidic conditions.

  6. Development of a new controlled pesticide delivery system based on neem leaf powder.

    PubMed

    Singh, Baljit; Sharma, D K; Kumar, Ramesh; Gupta, Atul

    2010-05-15

    In order to minimize the agro-environmental pollution and health hazards caused by pesticides, in the present study, the neem leaf powder "(NLP)", a bio-pesticide, has been exploited to develop the pesticide delivery devices. The presence of neem in the formulations along with the pesticide may enhance the potential of these systems due to its inherent pesticidal activity. We have prepared the NLP and alginate based beads by using CaCl(2) as crosslinker. To study the effect of composition of the beads on the release dynamics of fungicide (thiram), beads were prepared by varying the amount of NLP and crosslinker. The beads formed were characterized with Fourier transform infrared spectroscopy (FTIR), scanning electron micrograph (SEM), energy dispersion analysis by X-rays (EDAX), thermogravimetric analysis and swelling study. Formulation characteristics such as entrapment efficiency, bead size, percentage equilibrium swelling of the beads and diffusion mechanism for thiram release have been evaluated. Maximum (78.33+/-2.89)% swelling has occurred in the beads prepared with 1.5% NLP, 2.5% alginate and 0.1M crosslinker solution. In most of the formulations the values for the diffusion exponent 'n' have been obtained >1 and hence the release of fungicides occurred through Case II diffusion mechanism. PMID:20042287

  7. Representativeness and seasonality of major ion records derived from NEEM firn cores

    NASA Astrophysics Data System (ADS)

    Gfeller, G.; Fischer, H.; Bigler, M.; Schüpbach, S.; Leuenberger, D.; Mini, O.

    2014-05-01

    The seasonal and annual representativeness of ionic aerosol proxies (among others, calcium, sodium, ammonium and nitrate) in various firn cores in the vicinity of the NEEM drill site in north-west Greenland have been assessed. Seasonal representativeness is very high as one core explains more than 60% of the variability within the area. The inter-annual representativeness, however, can be substantially lower (depending on the species) making replicate coring indispensable to derive the atmospheric variability of aerosol species. A single core at the NEEM site records only 30% of the inter-annual atmospheric variability in some species, while five replicate cores are already needed to cover approximately 70% of the inter-annual atmospheric variability in all species. The spatial representativeness is very high within 60 cm, rapidly decorrelates within 10 m but does not diminish further within 3 km. We attribute this to wind reworking of the snow pack leading to sastrugi formation. Due to the high resolution and seasonal representativeness of the records we can derive accurate seasonalities of the measured species for modern times as well as for pre-industrial times. Sodium and calcium show similar seasonality (peaking in February and March respectively) for modern and pre-industrial times, whereas ammonium and nitrate are influenced by anthropogenic activities. Nitrate and ammonium both peak in May during modern times, whereas during pre-industrial times ammonium peaked during July-August and nitrate during June-July.

  8. Effect of neem extract against the bacteria isolated from marine fish.

    PubMed

    Dhayanithi, N B; Kumar, T T Ajith; Kathiresan, K

    2010-07-01

    Marine ornamental fishes are exceedingly valuable due to their high demand in domestic and international markets. There is a growing global interest to rear the fishes in captivity. But problem due to bacteria and fungi are the major hitch in captive condition. Since, the use of antibiotics is banned, an attempt was made to ascertain in vitro assay of the neem leaves extract against the bacterial pathogens isolated from infected fishes. Bacterial strains isolated from infected regions of the clown fishes Amphiprion sebae and A. ocellaris were identified as Aeromonas hydrophila, Enterobacter sp., E. coli, Pseudomonas aeruginosa, Proteus sp., Streptococcus sp., Vibrio cholerae, V. alginolyticus, V. parahaemolyticus and Yersinia enterocolitica. Ethanol and methanol extracts were highly inhibitory to the bacterial isolates when compared to other solvents. Ethanol extracts exhibited low minimum inhibitory concentration (75-250 microg ml(-1)) as compared to other extracts. The present finding revealed that the neem leaf extract significantly reduces the bacterial pathogens and their infection in marine ornamental fishes.

  9. Fire in ice: two millennia of boreal forest fire history from the Greenland NEEM ice core

    NASA Astrophysics Data System (ADS)

    Zennaro, P.; Kehrwald, N.; McConnell, J. R.; Schüpbach, S.; Maselli, O. J.; Marlon, J.; Vallelonga, P.; Leuenberger, D.; Zangrando, R.; Spolaor, A.; Borrotti, M.; Barbaro, E.; Gambaro, A.; Barbante, C.

    2014-10-01

    Biomass burning is a major source of greenhouse gases and influences regional to global climate. Pre-industrial fire-history records from black carbon, charcoal and other proxies provide baseline estimates of biomass burning at local to global scales spanning millennia, and are thus useful to examine the role of fire in the carbon cycle and climate system. Here we use the specific biomarker levoglucosan together with black carbon and ammonium concentrations from the North Greenland Eemian (NEEM) ice cores (77.49° N, 51.2° W; 2480 m a.s.l) over the past 2000 years to infer changes in boreal fire activity. Increases in boreal fire activity over the periods 1000-1300 CE and decreases during 700-900 CE coincide with high-latitude NH temperature changes. Levoglucosan concentrations in the NEEM ice cores peak between 1500 and 1700 CE, and most levoglucosan spikes coincide with the most extensive central and northern Asian droughts of the past millennium. Many of these multi-annual droughts are caused by Asian monsoon failures, thus suggesting a connection between low- and high-latitude climate processes. North America is a primary source of biomass burning aerosols due to its relative proximity to the Greenland Ice Cap. During major fire events, however, isotopic analyses of dust, back trajectories and links with levoglucosan peaks and regional drought reconstructions suggest that Siberia is also an important source of pyrogenic aerosols to Greenland.

  10. Expedient preparative isolation and tandem mass spectrometric characterization of C-seco triterpenoids from Neem oil.

    PubMed

    Haldar, Saikat; Mulani, Fayaj A; Aarthy, Thiagarayaselvam; Dandekar, Devdutta S; Thulasiram, Hirekodathakallu V

    2014-10-31

    C-seco triterpenoids are widely bioactive class of natural products with high structural complexity and diversity. The preparative isolation of these molecules with high purity is greatly desirable, although restricted due to the complexity of natural extracts. In this article we have demonstrated a Medium Pressure Liquid Chromatography (MPLC) based protocol for the isolation of eight major C-seco triterpenoids of salannin skeleton from Neem (Azadirachta indica) oil. Successive application of normal phase pre-packed silica-gel columns for the fractionation followed by reverse phase in automated MPLC system expedited the process and furnished highly pure metabolites. Furthermore, eight isolated triterpenoids along with five semi-synthesized derivatives were characterized using ultra performance liquid chromatography-electrospray ionization-quadrupole/orbitrap-MS/MS spectrometry as a rapid and sensitive identification technique. The structure-fragment relationships were established on the basis of plausible mechanistic pathway for the generation of daughter ions. The MS/MS spectral information of the triterpenoids was further utilized for the identification of studied molecules in the complex extract of stem and bark tissues from Neem.

  11. Representativeness and seasonality of major ion records derived from NEEM firn cores

    NASA Astrophysics Data System (ADS)

    Gfeller, G.; Fischer, H.; Bigler, M.; Schüpbach, S.; Leuenberger, D.; Mini, O.

    2014-10-01

    The seasonal and annual representativeness of ionic aerosol proxies (among others, calcium, sodium, ammonium and nitrate) in various firn cores in the vicinity of the NEEM drill site in northwest Greenland have been assessed. Seasonal representativeness is very high as one core explains more than 60% of the variability within the area. The inter-annual representativeness, however, can be substantially lower (depending on the species) making replicate coring indispensable to derive the atmospheric variability of aerosol species. A single core at the NEEM site records only 30% of the inter-annual atmospheric variability in some species, while five replicate cores are already needed to cover approximately 70% of the inter-annual atmospheric variability in all species. The spatial representativeness is very high within 60 cm, rapidly decorrelates within 10 m but does not diminish further within 3 km. We attribute this to wind reworking of the snow pack leading to sastrugi formation. Due to the high resolution and seasonal representativeness of the records we can derive accurate seasonalities of the measured species for modern (AD 1990-2010) times as well as for pre-industrial (AD 1623-1750) times. Sodium and calcium show similar seasonality (peaking in February and March respectively) for modern and pre-industrial times, whereas ammonium and nitrate are influenced by anthropogenic activities. Nitrate and ammonium both peak in May during modern times, whereas during pre-industrial times ammonium peaked during July-August and nitrate during June-July.

  12. Sub-chronic effect of neem based pesticide (Vepacide) on acetylcholinesterase and ATPases in rat.

    PubMed

    Rahman, M F; Siddiqui, M K; Jamil, K

    1999-09-01

    Acetylcholinesterases (AChE), Na(+)-K+, Mg2+ and Ca(2+)-ATPases were monitored in rat brain when treated orally with 80, 160 and 320 mg/kg of Vepacide, an active ingredient from neem seed oil, daily for 90 days. Brain AChE, Na(+)-K+ and Ca(2+)-ATPases were inhibited whereas Mg(2+)-ATPase levels were enhanced in both the sexes after 45 and 90 days of treatment. The relative sensitivities of these ATPases to Vepacide indicated that Ca(2+)-ATPase being more sensitive than Na(+)-K(+)-ATPase in both the sexes. The magnitude of Ca(2+)-ATPase inhibited by this compound was higher than that of brain AChE. It appears to be sexual dimorphism in the alterations of brain AChE, Na(+)-K+ and Mg(2+)-ATPases by Vepacide with females being significant when compared with males. After 28 days of post treatment the alterations observed were approached to those of controls both in male and female rats showing reversal of the toxicity. These results indicated that the ATPases were potently inhibited by Vepacide and seemed to be its precise target among the enzyme studied. This can be used as biochemical marker of exposure to this neem derived product. PMID:10466107

  13. Effect of Fertilizers and Neem Cake Amendment in Soil on Spore Germination of Arthrobotrys dactyloides

    PubMed Central

    Kumar, D.; Jaiswal, R. K.

    2005-01-01

    Application of fertilizers such as urea, diammonium phosphate (DAP) and muriate of potash in soil adversely affected the spore germination of Arthrobotrys dactyloides. Amendment of soil with urea at the concentrations of 1.0%, 0.5% and 0.1% completely inhibited spore germination and direct trap formation on the conidium, whereas muriate of potash delayed and reduced the spore germination even at the lowest concentration. DAP also inhibited spore germination at 1.0% concentration, while at lower concentration the percentage of spore germination was reduced. Application of neem cake at the concentration of 0.5% also inhibited spore germination after 24 h of amendment. The inhibitory effect of neem cake was reduced after 15 days of amendment, while after 30 days after amendment the inhibitory effect was completely lost and the spore germinated by direct trap as in unamended soil. Nematodes were not attracted to ungerminated spores after 24 h of amendment. After 15 days of amendment nematodes were attracted to agar blocks containing fewer germinated spores after 24 h of incubation but after 48 h of incubation large number of nematodes were attracted and trapped by the germinated spores with direct traps. After 30 days of amendment, larger number of nematodes were attracted and trapped by direct traps. PMID:24049500

  14. Mineral dust and major ion concentrations in snowpit samples from the NEEM site, Greenland

    NASA Astrophysics Data System (ADS)

    Kang, Jung-Ho; Hwang, Heejin; Hong, Sang Bum; Hur, Soon Do; Choi, Sung-Deuk; Lee, Jeonghoon; Hong, Sungmin

    2015-11-01

    Polar ice sheets conserve atmospheric aerosols at the time of snowfall, which can be used to reconstruct past climate and environmental conditions. We investigated mineral dust and major ion records in snowpit samples obtained from the northwestern Greenland ice sheet near the North Greenland Eemian Ice Drilling (NEEM) camp in June 2009. We analyzed the samples for mineral dust concentrations as well as stable water isotopes (δ18O, δD, and deuterium excess) and major ions (Cl-, SO42-, methanesulfonic acid (MSA), Na+, and Ca2+). Seasonal δ18O and δD cycles indicate that the snowpit samples covered a six-year period from spring 2003 to early summer 2009. Concentrations of mineral dust, nss-Ca2+, and nss-SO42- showed seasonal deposition events with maxima in the winter-spring layers. On the other hand, the Cl-/Na+ ratio and the concentrations of MSA exhibited maxima in the summer layers, making them useful indicators for the summer season. Moreover, an anomalous atmospheric mineral dust event was recorded at a depth of 165-170 cm corresponding to late winter 2005 to spring 2006. A back trajectory analysis suggests that a major contributor to the Greenland aerosol was an air mass passing over the Canadian Arctic and North America. Several trajectories point to Asian regions as a dust source. The mineral dust deposited at NEEM was strongly influenced by long-range atmospheric transport and dust input from arid source areas in northern China and Mongolia.

  15. Efficacy of crude neem seed kernel extracts against natural infestation of Sarcoptes scabiei var. ovis.

    PubMed

    Tabassam, Shahid Maqsood; Iqbal, Zafar; Jabbar, Abdul; Sindhu, Zia-ud-Din; Chattha, Amjad Iqbal

    2008-01-17

    This study was aimed to evaluate the efficacy of crude aqueous-methanol and aqueous extracts of neem (Azadirachta indica) seed kernel against sarcoptic mange of sheep. Crude aqueous-methanol (AME) and aqueous extracts (AE) of neem seed kernel (NSK) were prepared and formulated as 10% and 20% ointments (w/w), using Vaseline as vehicle. Forty-two lambs of Pak Karakul breed, having natural infection of sarcoptic mange were divided into seven experimental groups. Skin scrapings and clinical examination were carried out at scheduled intervals after treatment. Ivermectin (positive control) completely cleared infesting mites from animals after 10 days and 20% AME after 16 days. While, clinical mange was completely cured after 16 and 20 days with ivermectin and 20% AME, respectively, under field conditions. Only the higher concentration (20% AME) of NSK extracts completely cured the clinical mange, suggesting a dose-dependent response. Our results consolidate the belief that use of folk remedies can provide an effective and economic way of combating sarcoptic mange in sheep. PMID:18023309

  16. Expedient preparative isolation and tandem mass spectrometric characterization of C-seco triterpenoids from Neem oil.

    PubMed

    Haldar, Saikat; Mulani, Fayaj A; Aarthy, Thiagarayaselvam; Dandekar, Devdutta S; Thulasiram, Hirekodathakallu V

    2014-10-31

    C-seco triterpenoids are widely bioactive class of natural products with high structural complexity and diversity. The preparative isolation of these molecules with high purity is greatly desirable, although restricted due to the complexity of natural extracts. In this article we have demonstrated a Medium Pressure Liquid Chromatography (MPLC) based protocol for the isolation of eight major C-seco triterpenoids of salannin skeleton from Neem (Azadirachta indica) oil. Successive application of normal phase pre-packed silica-gel columns for the fractionation followed by reverse phase in automated MPLC system expedited the process and furnished highly pure metabolites. Furthermore, eight isolated triterpenoids along with five semi-synthesized derivatives were characterized using ultra performance liquid chromatography-electrospray ionization-quadrupole/orbitrap-MS/MS spectrometry as a rapid and sensitive identification technique. The structure-fragment relationships were established on the basis of plausible mechanistic pathway for the generation of daughter ions. The MS/MS spectral information of the triterpenoids was further utilized for the identification of studied molecules in the complex extract of stem and bark tissues from Neem. PMID:25267707

  17. Comparative transcripts profiling of fruit mesocarp and endocarp relevant to secondary metabolism by suppression subtractive hybridization in Azadirachta indica (neem).

    PubMed

    Narnoliya, Lokesh K; Rajakani, Raja; Sangwan, Neelam S; Gupta, Vikrant; Sangwan, Rajender S

    2014-05-01

    Azadirachta indica (neem) is a medicinally important plant that is valued for its bioactive secondary metabolites. Higher levels of the bioactive phytochemicals are accumulated in fruits than in other tissues. In the present study, a total of 387 and 512 ESTs, respectively, from endocarp and mesocarp of neem fruits were isolated and analyzed. Out of them 318 ESTs (82.17%) clones from endocarp and 418 ESTs (81.64%) from mesocarp encoded putative proteins that could be classified into three major gene ontology categories: biological process, molecular function and cellular component. From the analyses of contigs, 73 unigenes from the forward subtracted library and 35 unigenes from the reverse subtracted library were obtained. The ESTs from mesocarp encoded cytochrome P450 enzymes, which indicated hydroxylation to be a major metabolic event and that biogeneration of hydroxylated neem fruit phytochemicals was differentially regulated with developmental stage-specificity of synthesis. Through this study, we present the first report of any gene expression data in neem tissues. Neem hydroxy-methyl glutaryl-coenzyme A reductase (NHMGR) gene was used as expressing control vis-a-vis subtracted tissues. NHMGR was present in fruit, endocarp and mesocarp tissues, but absent in subtractive libraries, revealing that it was successfully eliminated during subtraction. Eight genes of interest from subtracted libraries were profiled for their expression in fruit, mesocarp and endocarp. Expression profiles validated the quality of the libraries and functional diversity of the tissues. The subtractive cDNA library and EST database described in this study represent a valuable transcript sequence resource for future research aimed at improving the economically important medicinal plant.

  18. Inhibition of the growth and development of asexual and sexual stages of drug-sensitive and resistant strains of the human malaria parasite Plasmodium falciparum by Neem (Azadirachta indica) fractions.

    PubMed

    Dhar, R; Zhang, K; Talwar, G P; Garg, S; Kumar, N

    1998-05-01

    Neem (Azadirachta indica) has been shown to possess anti-malarial activity. In this study we systematically evaluated extracts of neem seeds and purified fractions further enriched in polar or non-polar constituents for their effect on in vitro growth and development of asexual and sexual stages of the human malaria parasite Plasmodium falciparum. Use of synchronized stages of parasites suggested trophozoites/schizonts as the susceptible target stages to various neem extracts. In addition, all the maturation stages of gametocytes were also killed by various neem fractions tested. The anti-plasmodial effect of neem components was also observed on parasites previously shown to be resistant to other anti-malarial drugs, i.e. chloroquine and pyrimethamine suggesting a different mode of action. Neem seed fractions are thus active not only against the parasite stages that cause the clinical infection but also against the stages responsible for continued malaria transmission. PMID:9687079

  19. Biochemical and histological studies of reproductive organs in cyclic and ovariectomized rats supporting a non-hormonal action for neem oil.

    PubMed

    Tewari, R K; Pathak, S; Prakash, A O

    1989-05-01

    Subcutaneous administration of neem oil to cyclic rats caused significant damage to the luminal epithelium of the uterus and to the uterine glands. It also decreased glycogen and total protein contents in the ovary and uterus, while the activity of acid phosphatase in these organs was increased significantly. Studies in ovariectomized rats revealed that the administration of neem oil decreased protein and glycogen content and increased acid phosphatase activity in the uterus whereas its conjoint administration with estradiol dipropionate or progesterone did not cause significant changes relative to those seen with the steroids per se. Histological studies in ovariectomized rats also supported the relatively inert action of neem oil when given with hormones. It was concluded that the histological and biochemical alterations observed were due to the toxicological potential of the neem oil rather than to hormonal properties. PMID:2747262

  20. Insecticide residues in head lettuce, cabbage, Chinese cabbage, and broccoli grown in fields.

    PubMed

    Chen, Miao-Fan; Chen, Jung-Fang; Syu, Jing-Jing; Pei, Chi; Chien, Hsiu-Pao

    2014-04-23

    The residues of four insecticides belonging to different families were studied on head lettuce (Lactuca sativa L. var. capitata L.), cabbage (Brassica oleracea Linn. var. capitata DC.), Chinese cabbage (Brassica pekinensis Skeels), and broccoli (Brassica oleracea var. italica) after pesticide application. To reduce application variability, a tank mix of acetamiprid 20% SP, chlorpyrifos 22.5% EC, deltamethrin 2.4% SC, and methomyl 40% SP was applied at recommended and double doses. Initial deposits of all pesticides on head lettuce were higher than those of the other three crops. The residues of chlorpyrifos and deltamethrin were higher than the maximum residue limits (MRLs) at recommended preharvest intervals (PHIs) on head lettuce and Chinese broccoli treated with higher doses. The residues of methomyl on head lettuce also showed the same phenomenon. PMID:24684565

  1. Variation in toxicity of a current-use insecticide among resurrected Daphnia pulicaria genotypes.

    PubMed

    Simpson, Adam M; Jeyasingh, Punidan D; Belden, Jason B

    2015-04-01

    This study examined how genotypes of Daphnia pulicaria from a single population, separated by thousands of generations of evolution in the wild, differ in their sensitivity to a novel anthropogenic stressor. These genotypes were resurrected from preserved resting eggs isolated from sediments belonging to three time periods: 2002-2008, 1967-1977, and 1301-1646 A.D. Toxicity of the organophosphate insecticide chlorpyrifos was determined through a series of acute toxicity tests. There was a significant dose-response effect in all genotypes studied. Moreover, significant variation in toxicity among genotypes within each time period was detected. Importantly, a significant effect of time period on sensitivity to chlorpyrifos was found. Analysis of the median effect concentrations (EC50s) for genotypes within each time period indicated that the 1301-1646 genotypes were 2.7 times more sensitive than the 1967-1977 genotypes. This trend may be partially explained by microevolutionary shifts in response to cultural eutrophication.

  2. Insecticide residues on weathered passerine carcass feet

    USGS Publications Warehouse

    Vyas, N.B.; Spann, J.W.; Hulse, C.S.; Butterbrodt, J.J.; Mengelkoch, J.; MacDougall, K.; Williams, B.; Pendergrass, P.

    2003-01-01

    Nine brown-headed cowbirds (Molothrus ater) were exposed to turf srayed with either EarthCare? (25% diazinon; 477 L a.i./ha) or Ortho-Klor? (12 .6% chlorpyrifos; 5.21 L a.i./ha.). Birds were euthanized and one foot from each bird was weathered outdoors for up to 28 days and the other foot was kept frozen until residue analysis. When compared to the unweathered feet, feet weathered for 28 days retained 43% and 37% of the diazinon and chlorpyrifors, respectively. Insecticide residues were below the level of detection (1.0 ppm) on control feet. Weathered feet may be used for determining organophosphorus insecticide exposure to birds.

  3. Insect sodium channels and insecticide resistance

    PubMed Central

    2011-01-01

    Voltage-gated sodium channels are essential for the generation and propagation of action potentials (i.e., electrical impulses) in excitable cells. Although most of our knowledge about sodium channels is derived from decades of studies of mammalian isoforms, research on insect sodium channels is revealing both common and unique aspects of sodium channel biology. In particular, our understanding of the molecular dynamics and pharmacology of insect sodium channels has advanced greatly in recent years, thanks to successful functional expression of insect sodium channels in Xenopus oocytes and intensive efforts to elucidate the molecular basis of insect resistance to insecticides that target sodium channels. In this review, I discuss recent literature on insect sodium channels with emphases on the prominent role of alternative splicing and RNA editing in the generation of functionally diverse sodium channels in insects and the current understanding of the interactions between insect sodium channels and insecticides. PMID:17206406

  4. Insecticide tolerance of Culex nigripalpus in Florida.

    PubMed

    Boike, A H; Rathburn, C B; Floore, T G; Rodriguez, H M; Coughlin, J S

    1989-12-01

    Larval susceptibility tests of Culex nigripalpus populations from various areas of Florida have shown resistance to several organophosphorus insecticides since 1984. Although the degree of resistance is low (2 to 7 times), it can be termed tolerance and appears to be the greatest for fenthion, followed by temephos, naled and malathion. It is suggested that pesticide runoff from lawns, golf courses and agricultural and urban areas may play a role in developing resistance in Florida mosquito populations. PMID:2614401

  5. Gene Expression Responses Linked to Reproduction Effect Concentrations (EC10,20,50,90) of Dimethoate, Atrazine and Carbendazim, in Enchytraeus albidus

    PubMed Central

    Novais, Sara C.; De Coen, Wim; Amorim, Mónica J. B.

    2012-01-01

    Background Molecular mechanisms of response to pesticides are scarce and information on such responses from soil invertebrates is almost inexistent. Enchytraeus albidus (Oligochaeta) is a standard soil ecotoxicology model species for which effects of many pesticides are known on survival, reproduction and avoidance behaviour. With the recent microarray development additional information can be retrieved on the molecular effects. Methodology/Principal Findings Experiments were performed to investigate the transcription responses of E. albidus when exposed to three pesticides – dimethoate (insecticide), atrazine (herbicide) and carbendazim (fungicide) – in a range of concentrations that inhibited reproduction by 10%, 20%, 50% and 90% (EC10, EC20, EC50 and EC90, respectively). The goal of this study was to further identify key biological processes affected by each compound and if dose-related. All three pesticides significantly affected biological processes like translation, regulation of the cell cycle or general response to stress. Intracellular signalling and microtubule-based movement were affected by dimethoate and carbendazim whereas atrazine affected lipid and steroid metabolism (also by dimethoate) or carbohydrate metabolism (also by carbendazim). Response to DNA damage/DNA repair was exclusively affected by carbendazim. Conclusions Changes in gene expression were significantly altered after 2 days of exposure in a dose-related manner. The mechanisms of response were comparable with the ones for mammals, suggesting across species conserved modes of action. The present results indicate the potential of using gene expression in risk assessment and the advantage as early markers. PMID:22558331

  6. Recent changes in north-west Greenland climate documented by NEEM shallow ice core data and simulations, and implications for past temperature reconstructions

    NASA Astrophysics Data System (ADS)

    Masson-Delmotte, V.; Steen-Larsen, H. C.; Ortega, P.; Swingedouw, D.; Popp, T.; Vinther, B. M.; Oerter, H.; Sveinbjornsdottir, A. E.; Gudlaugsdottir, H.; Box, J. E.; Falourd, S.; Fettweis, X.; Gallée, H.; Garnier, E.; Jouzel, J.; Landais, A.; Minster, B.; Paradis, N.; Orsi, A.; Risi, C.; Werner, M.; White, J. W. C.

    2015-01-01

    Combined records of snow accumulation rate, δ18O and deuterium excess were produced from several shallow ice cores and snow pits at NEEM (north-west Greenland), covering the period from 1724 to 2007. They are used to investigate recent climate variability and characterize the isotope-temperature relationship. We find that NEEM records are only weakly affected by inter-annual changes in the North Atlantic Oscillation. Decadal δ18O and accumulation variability is related to North Atlantic SST, and enhanced at the beginning of the 19th century. No long-term trend is observed in the accumulation record. By contrast, NEEM δ18O shows multi-decadal increasing trends in the late 19th century and since the 1980s. The strongest annual positive δ18O anomaly values are recorded at NEEM in 1928 and 2010, while maximum accumulation occurs in 1933. The last decade is the most enriched in δ18O (warmest), while the 11-year periods with the strongest depletion (coldest) are depicted at NEEM in 1815-1825 and 1836-1846, which are also the driest 11-year periods. The NEEM accumulation and δ18O records are strongly correlated with outputs from atmospheric models, nudged to atmospheric reanalyses. Best performance is observed for ERA reanalyses. Gridded temperature reconstructions, instrumental data and model outputs at NEEM are used to estimate the multi-decadal accumulation-temperature and δ18O-temperature relationships for the strong warming period in 1979-2007. The accumulation sensitivity to temperature is estimated at 11 ± 2% °C-1 and the δ18O-temperature slope at 1.1 ± 0.2‰ °C-1, about twice larger than previously used to estimate last interglacial temperature change from the bottom part of the NEEM deep ice core.

  7. Recent changes in north-west Greenland climate documented by NEEM shallow ice core data and simulations, and implications for past-temperature reconstructions

    NASA Astrophysics Data System (ADS)

    Masson-Delmotte, V.; Steen-Larsen, H. C.; Ortega, P.; Swingedouw, D.; Popp, T.; Vinther, B. M.; Oerter, H.; Sveinbjornsdottir, A. E.; Gudlaugsdottir, H.; Box, J. E.; Falourd, S.; Fettweis, X.; Gallée, H.; Garnier, E.; Gkinis, V.; Jouzel, J.; Landais, A.; Minster, B.; Paradis, N.; Orsi, A.; Risi, C.; Werner, M.; White, J. W. C.

    2015-08-01

    Combined records of snow accumulation rate, δ18O and deuterium excess were produced from several shallow ice cores and snow pits at NEEM (North Greenland Eemian Ice Drilling), covering the period from 1724 to 2007. They are used to investigate recent climate variability and characterise the isotope-temperature relationship. We find that NEEM records are only weakly affected by inter-annual changes in the North Atlantic Oscillation. Decadal δ18O and accumulation variability is related to North Atlantic sea surface temperature and is enhanced at the beginning of the 19th century. No long-term trend is observed in the accumulation record. By contrast, NEEM δ18O shows multidecadal increasing trends in the late 19th century and since the 1980s. The strongest annual positive δ18O values are recorded at NEEM in 1928 and 2010, while maximum accumulation occurs in 1933. The last decade is the most enriched in δ18O (warmest), while the 11-year periods with the strongest depletion (coldest) are depicted at NEEM in 1815-1825 and 1836-1846, which are also the driest 11-year periods. The NEEM accumulation and δ18O records are strongly correlated with outputs from atmospheric models, nudged to atmospheric reanalyses. Best performance is observed for ERA reanalyses. Gridded temperature reconstructions, instrumental data and model outputs at NEEM are used to estimate the multidecadal accumulation-temperature and δ18O-temperature relationships for the strong warming period in 1979-2007. The accumulation sensitivity to temperature is estimated at 11 ± 2 % °C-1 and the δ18O-temperature slope at 1.1 ± 0.2 ‰ °C-1, about twice as large as previously used to estimate last interglacial temperature change from the bottom part of the NEEM deep ice core.

  8. Behavioral and developmental effects of neem extracts on Clavigralla scutellaris (Hemiptera: Heteroptera: Coreidae) and its egg parasitoid, Gryon fulviventre (Hymenoptera: Scelionidae).

    PubMed

    Mitchell, Paula Levin; Gupta, Reetika; Singh, Ashok K; Kumar, Pradyumn

    2004-06-01

    Extracts of neem, Azadirachta indica A. Juss, negatively affected feeding and development of Clavigralla scutellaris (Westwood), a coreid pest of pigeonpea, Cajanus cajan (L.) Millspaugh. Labial dabbing, pod wall penetration, and seed damage by fifth instars were significantly reduced on beans, Phaseolus vulgaris (L.), that had been dipped in aqueous, methanolic, or hexane extracts of neem seed kernel. When fourth instars were dipped directly into aqueous extract, developmental abnormalities of the wings occurred at all levels tested and fecundity dropped to zero at concentrations above 0.3125%. The LC50 value was 3.14% (220 ppm azadirachtin) at 8 d. The scelionid wasp Gryon fulviventre (Crawford) is an important natural enemy of Clavigralla spp.; egg mortality from this parasitoid ranged from 37 to 85% during the fall cropping season. Feeding by newly emerged wasps was dramatically reduced when honey was mixed with aqueous neem suspension, but 6-d survivorship of adults did not differ significantly from that of the control. Wasp oviposition behavior was altered slightly when coreid eggs were treated with neem: the period of antennation was significantly extended, but time for drilling, oviposition, and marking was unaffected. Neem-dipped eggs were accepted for oviposition and progeny emerged successfully from these treated eggs. Exposure of already parasitized eggs to neem did not interfere with progeny emergence, longevity, or sex ratio. Thus, neem extract and egg parasitoids seem to be compatible and promising control strategies for C. scutellaris. Our results suggest that use of neem against pod-sucking bugs will not interfere with natural control provided by G. fulviventre. PMID:15279272

  9. The Molecular Genetics of Insecticide Resistance

    PubMed Central

    ffrench-Constant, Richard H.

    2013-01-01

    The past 60 years have seen a revolution in our understanding of the molecular genetics of insecticide resistance. While at first the field was split by arguments about the relative importance of mono- vs. polygenic resistance and field- vs. laboratory-based selection, the application of molecular cloning to insecticide targets and to the metabolic enzymes that degrade insecticides before they reach those targets has brought out an exponential growth in our understanding of the mutations involved. Molecular analysis has confirmed the relative importance of single major genes in target-site resistance and has also revealed some interesting surprises about the multi-gene families, such as cytochrome P450s, involved in metabolic resistance. Identification of the mutations involved in resistance has also led to parallel advances in our understanding of the enzymes and receptors involved, often with implications for the role of these receptors in humans. This Review seeks to provide an historical perspective on the impact of molecular biology on our understanding of resistance and to begin to look forward to the likely impact of rapid advances in both sequencing and genome-wide association analysis. PMID:23908373

  10. Insecticide Resistance and Management Strategies in Urban Ecosystems

    PubMed Central

    Zhu, Fang; Lavine, Laura; O’Neal, Sally; Lavine, Mark; Foss, Carrie; Walsh, Douglas

    2016-01-01

    The increased urbanization of a growing global population makes imperative the development of sustainable integrated pest management (IPM) strategies for urban pest control. This emphasizes pests that are closely associated with the health and wellbeing of humans and domesticated animals. Concurrently there are regulatory requirements enforced to minimize inadvertent exposures to insecticides in the urban environment. Development of insecticide resistance management (IRM) strategies in urban ecosystems involves understanding the status and mechanisms of insecticide resistance and reducing insecticide selection pressure by combining multiple chemical and non-chemical approaches. In this review, we will focus on the commonly used insecticides and molecular and physiological mechanisms underlying insecticide resistance in six major urban insect pests: house fly, German cockroach, mosquitoes, red flour beetle, bed bugs and head louse. We will also discuss several strategies that may prove promising for future urban IPM programs. PMID:26751480

  11. Insecticide Resistance and Management Strategies in Urban Ecosystems.

    PubMed

    Zhu, Fang; Lavine, Laura; O'Neal, Sally; Lavine, Mark; Foss, Carrie; Walsh, Douglas

    2016-01-01

    The increased urbanization of a growing global population makes imperative the development of sustainable integrated pest management (IPM) strategies for urban pest control. This emphasizes pests that are closely associated with the health and wellbeing of humans and domesticated animals. Concurrently there are regulatory requirements enforced to minimize inadvertent exposures to insecticides in the urban environment. Development of insecticide resistance management (IRM) strategies in urban ecosystems involves understanding the status and mechanisms of insecticide resistance and reducing insecticide selection pressure by combining multiple chemical and non-chemical approaches. In this review, we will focus on the commonly used insecticides and molecular and physiological mechanisms underlying insecticide resistance in six major urban insect pests: house fly, German cockroach, mosquitoes, red flour beetle, bed bugs and head louse. We will also discuss several strategies that may prove promising for future urban IPM programs. PMID:26751480

  12. Differences in susceptibility of five cladoceran species to two systemic insecticides, imidacloprid and fipronil.

    PubMed

    Hayasaka, Daisuke; Korenaga, Tomoko; Suzuki, Kazutaka; Sánchez-Bayo, Francisco; Goka, Koichi

    2012-03-01

    Differences in susceptibility of five cladocerans to the neonicotinoid imidacloprid and the phenyl-pyrazole fipronil, which have been dominantly used in rice fields of Japan in recent years, were examined based on short-term (48-h), semi-static acute immobilization exposure tests. Additionally, we compared the species sensitivity distribution (SSD) patterns of both insecticides between two sets of species: the five tested cladocerans and all other aquatic organisms tested so far, using data from the ECOTOX database of U.S. Environmental Protection Agency (USEPA). The sensitivity of the test species to either imidacloprid or fipronil was consistent, spanning similar orders of magnitude (100 times). At the genus level, sensitivities to both insecticides were in the following descending order: Ceriodaphnia > Moina > Daphnia. A positive relationship was found between body lengths of each species and the acute toxicity (EC(50)) of the insecticides, in particular fipronil. Differences in SSD patterns of imidacloprid were found between the species groups compared, indicating that test cladocerans are much less susceptible than other aquatic species including amphibians, crustaceans, fish, insects, mollusks and worms. However, the SSD patterns for fipronil indicate no difference in sensitivity between cladocerans tested and other aquatic organisms despite the greater exposure, which overestimates the results, of our semi-static tests. From these results, Ceriodaphnia sp. should be considered as more sensitive bioindicators (instead of the standard Daphnia magna) for ecotoxicological assessments of aquatic ecosystems. In addition, we propose that ecotoxicity data associated with differences in susceptibility among species should be investigated whenever pesticides have different physicochemical properties and mode of action. PMID:21971973

  13. Chemical composition of Eucalyptus spp. essential oils and their insecticidal effects on Lutzomyia longipalpis.

    PubMed

    Maciel, M V; Morais, S M; Bevilaqua, C M L; Silva, R A; Barros, R S; Sousa, R N; Sousa, L C; Brito, E S; Souza-Neto, M A

    2010-01-20

    The chemical composition of essential oils from three species of plants belonging to the Eucalyptus genus was determined and, their insecticidal effects on egg, larva and adult phases of Lutzomyia longipalpis were assessed. The insects were collected in the municipality of Sobral in the State of Ceará, Brazil. Five treatments with different concentrations were performed along with two negative controls, distilled water and Tween 80 (3%), and a positive control, cypermethrin (0.196mg/ml). The tests were carried out in plastic pots internally coated with sterile plaster and filled with a substrate made of rabbit feces and crushed cassava leaves. The eggs, larvae and adults were sprayed with the oils. The hatched larvae were counted for 10 consecutive days and observed until pupation. Insect mortality was observed after 24, 48 and 72h. E. staigeriana oil was the most effective on all three phases of the insect, followed by E. citriodora and E. globulus oils, respectively. The major constituents of the oils were Z-citral and alpha-citral (E. staigeriana), citronellal (E. citriodora) and 1,8-cineole (E. globulus). The Eucalyptus essential oils constitute alternative natural products for the control of L. longipalpis since the median effective concentration (EC(50)) values revealed relevant action as compared with other natural products, some of their chemical constituents are already known for their insecticidal activity and these oils are produced in commercial scale in Brazil. PMID:19896276

  14. Effects of neem oil (Azadirachta indica A. Juss) on the replacement of the midgut epithelium in the lacewing Ceraeochrysa claveri during larval-pupal metamorphosis.

    PubMed

    Scudeler, Elton Luiz; Padovani, Carlos Roberto; Santos, Daniela Carvalho Dos

    2014-06-01

    Larvae of the lacewing Ceraeochrysa claveri were fed on eggs of Diatraeasaccharalis treated with neem oil at concentrations of 0.5%, 1% and 2% throughout the larval period. Pupae obtained from treated larvae were used in the study at five days after the completion of cocoon spinning to investigate the effects of neem oil on the replacement of the midgut epithelium during the larval-pupal transition. We observed that the old larval epithelium was shed into the midgut lumen and transformed into the yellow body. Old cells from the yellow body were destroyed by apoptosis and autophagy and were not affected by neem oil. However, neem oil did affect the new pupal epithelium. Cells from treated pupae showed cellular injuries such as a loss of microvilli, cytoplasmic vacuolization, an increase of glycogen stores, deformation of the rough endoplasmic reticulum and dilation of the perinuclear space. Additionally, the neem oil treatment resulted in the release of cytoplasmic protrusions, rupture of the plasma membrane and leakage of cellular debris into the midgut lumen, characteristics of cell death by necrosis. The results indicate that neem oil ingestion affects the replacement of midgut epithelium, causing cytotoxic effects that can alter the organism's physiology due to extensive cellular injuries.

  15. Effects of neem oil (Azadirachta indica A. Juss) on the replacement of the midgut epithelium in the lacewing Ceraeochrysa claveri during larval-pupal metamorphosis.

    PubMed

    Scudeler, Elton Luiz; Padovani, Carlos Roberto; Santos, Daniela Carvalho Dos

    2014-06-01

    Larvae of the lacewing Ceraeochrysa claveri were fed on eggs of Diatraeasaccharalis treated with neem oil at concentrations of 0.5%, 1% and 2% throughout the larval period. Pupae obtained from treated larvae were used in the study at five days after the completion of cocoon spinning to investigate the effects of neem oil on the replacement of the midgut epithelium during the larval-pupal transition. We observed that the old larval epithelium was shed into the midgut lumen and transformed into the yellow body. Old cells from the yellow body were destroyed by apoptosis and autophagy and were not affected by neem oil. However, neem oil did affect the new pupal epithelium. Cells from treated pupae showed cellular injuries such as a loss of microvilli, cytoplasmic vacuolization, an increase of glycogen stores, deformation of the rough endoplasmic reticulum and dilation of the perinuclear space. Additionally, the neem oil treatment resulted in the release of cytoplasmic protrusions, rupture of the plasma membrane and leakage of cellular debris into the midgut lumen, characteristics of cell death by necrosis. The results indicate that neem oil ingestion affects the replacement of midgut epithelium, causing cytotoxic effects that can alter the organism's physiology due to extensive cellular injuries. PMID:24560939

  16. A Method of EC Model Implementation Using Web Service Functions

    NASA Astrophysics Data System (ADS)

    Kurihara, Jun; Koizumi, Hisao; Ishikawa, Toshiyuki; Dasai, Takashi

    In recent years, advances in computer and communication technology and the associated rapid increase in the number of Internet users are encouraging advances in Electronic Commerce (EC). Business models of EC are being actively developed by many different enterprises and engineers, and implemented in many kinds of fields. Meanwhile Web services that reuse remote components over the Internet are drawing attention. Web services are based on SOAP/WSDL/UDDI and are given an important position as the infrastructure of the EC systems. The article analyzes the functions and structures of various business models, establishing the patterns of their distinctive and common features, and proposes a method of determining the implementation specifications of business models utilizing these patterns and Web service functions. This method has been applied to a parts purchasing system, which is a typical pattern of the B to B (Business to Business) EC applications. The article also discusses the results of evaluating this prototype system.

  17. Residue behavior of combination formulations of insecticides in/on cabbage and their efficacy against aphids and diamondback moth.

    PubMed

    Gupta, Suman; Sharma, Rakesh K; Gajbhiye, Vijay T; Gupta, Ram K

    2015-01-01

    Persistence behavior of insecticides chlorpyriphos, profenofos, triazophos, cypermethrin, and deltamethrin following the use of three combination formulations Action 505 (chlorpyriphos + cypermethrin), Roket 44EC (profenofos + cypermethrin), and Anaconda Plus (triazophos + deltamethrin) was studied in cabbage following the spray application at the recommended and double doses. Bio-efficacy of these formulations was also evaluated against mustard aphids (Lipaphis erysimi Kaltenbach) and diamondback moth (Plutella xylostella L.). The residues of different insecticides persisted for 5-8 days at low dose and 8-12 days at high dose. The residues dissipated with time and 87-100% dissipation was recorded on the 8th day. The half-life values varied from 0.4 to 1.6 days. Based on the acceptable daily intake (ADI) values, a safe waiting period of 1 day has been suggested for the formulations Action 505 and Roket 44EC and 3 days for Anaconda Plus at the recommended dose of application. Action (1.6 L/ha) treatment was found to be the best as it significantly reduced the diamondback moth (DBM) (~60%) and aphid population (~70%) besides giving the highest yield (170% increase over control). PMID:25384368

  18. Residue behavior of combination formulations of insecticides in/on cabbage and their efficacy against aphids and diamondback moth.

    PubMed

    Gupta, Suman; Sharma, Rakesh K; Gajbhiye, Vijay T; Gupta, Ram K

    2015-01-01

    Persistence behavior of insecticides chlorpyriphos, profenofos, triazophos, cypermethrin, and deltamethrin following the use of three combination formulations Action 505 (chlorpyriphos + cypermethrin), Roket 44EC (profenofos + cypermethrin), and Anaconda Plus (triazophos + deltamethrin) was studied in cabbage following the spray application at the recommended and double doses. Bio-efficacy of these formulations was also evaluated against mustard aphids (Lipaphis erysimi Kaltenbach) and diamondback moth (Plutella xylostella L.). The residues of different insecticides persisted for 5-8 days at low dose and 8-12 days at high dose. The residues dissipated with time and 87-100% dissipation was recorded on the 8th day. The half-life values varied from 0.4 to 1.6 days. Based on the acceptable daily intake (ADI) values, a safe waiting period of 1 day has been suggested for the formulations Action 505 and Roket 44EC and 3 days for Anaconda Plus at the recommended dose of application. Action (1.6 L/ha) treatment was found to be the best as it significantly reduced the diamondback moth (DBM) (~60%) and aphid population (~70%) besides giving the highest yield (170% increase over control).

  19. Identifying deformation mechanisms in the NEEM ice core using EBSD measurements

    NASA Astrophysics Data System (ADS)

    Kuiper, Ernst-Jan; Weikusat, Ilka; Drury, Martyn R.; Pennock, Gill M.; de Winter, Matthijs D. A.

    2015-04-01

    Deformation of ice in continental sized ice sheets determines the flow behavior of ice towards the sea. Basal dislocation glide is assumed to be the dominant deformation mechanism in the creep deformation of natural ice, but non-basal glide is active as well. Knowledge of what types of deformation mechanisms are active in polar ice is critical in predicting the response of ice sheets in future warmer climates and its contribution to sea level rise, because the activity of deformation mechanisms depends critically on deformation conditions (such as temperature) as well as on the material properties (such as grain size). One of the methods to study the deformation mechanisms in natural materials is Electron Backscattered Diffraction (EBSD). We obtained ca. 50 EBSD maps of five different depths from a Greenlandic ice core (NEEM). The step size varied between 8 and 25 micron depending on the size of the deformation features. The size of the maps varied from 2000 to 10000 grid point. Indexing rates were up to 95%, partially by saving and reanalyzing the EBSP patterns. With this method we can characterize subgrain boundaries and determine the lattice rotation configurations of each individual subgrain. Combining these observations with arrangement/geometry of subgrain boundaries the dislocation types can be determined, which form these boundaries. Three main types of subgrain boundaries have been recognized in Antarctic (EDML) ice core¹². Here, we present the first results obtained from EBSD measurements performed on the NEEM ice core samples from the last glacial period, focusing on the relevance of dislocation activity of the possible slip systems. Preliminary results show that all three subgrain types, recognized in the EDML core, occur in the NEEM samples. In addition to the classical boundaries made up of basal dislocations, subgrain boundaries made of non-basal dislocations are also common. ¹Weikusat, I.; de Winter, D. A. M.; Pennock, G. M.; Hayles, M

  20. Interactive effects of mosquito control insecticide toxicity, hypoxia, and increased carbon dioxide on larval and juvenile eastern oysters and hard clams.

    PubMed

    Garcia, R N; Chung, K W; Key, P B; Burnett, L E; Coen, L D; Delorenzo, M E

    2014-04-01

    Mosquito control insecticide use in the coastal zone coincides with the habitat and mariculture operations of commercially and ecologically important shellfish species. Few data are available regarding insecticide toxicity to shellfish early life stages, and potential interactions with abiotic stressors, such as low oxygen and increased CO2 (low pH), are less understood. Toxicity was assessed at 4 and 21 days for larval and juvenile stages of the Eastern oyster, Crassostrea virginica, and the hard clam, Mercenaria mercenaria, using two pyrethroids (resmethrin and permethrin), an organophosphate (naled), and a juvenile growth hormone mimic (methoprene). Acute toxicity (4-day LC50) values ranged from 1.59 to >10 mg/L. Overall, clams were more susceptible to mosquito control insecticides than oysters. Naled was the most toxic compound in oyster larvae, whereas resmethrin was the most toxic compound in clam larvae. Mortality for both species generally increased with chronic insecticide exposure (21-day LC50 values ranged from 0.60 to 9.49 mg/L). Insecticide exposure also caused sublethal effects, including decreased swimming activity after 4 days in larval oysters (4-day EC50 values of 0.60 to 2.33 mg/L) and decreased growth (shell area and weight) in juvenile clams and oysters after 21 days (detected at concentrations ranging from 0.625 to 10 mg/L). Hypoxia, hypercapnia, and a combination of hypoxia and hypercapnia caused mortality in larval clams and increased resmethrin toxicity. These data will benefit both shellfish mariculture operations and environmental resource agencies as they manage the use of mosquito control insecticides near coastal ecosystems.

  1. Interactive effects of mosquito control insecticide toxicity, hypoxia, and increased carbon dioxide on larval and juvenile eastern oysters and hard clams.

    PubMed

    Garcia, R N; Chung, K W; Key, P B; Burnett, L E; Coen, L D; Delorenzo, M E

    2014-04-01

    Mosquito control insecticide use in the coastal zone coincides with the habitat and mariculture operations of commercially and ecologically important shellfish species. Few data are available regarding insecticide toxicity to shellfish early life stages, and potential interactions with abiotic stressors, such as low oxygen and increased CO2 (low pH), are less understood. Toxicity was assessed at 4 and 21 days for larval and juvenile stages of the Eastern oyster, Crassostrea virginica, and the hard clam, Mercenaria mercenaria, using two pyrethroids (resmethrin and permethrin), an organophosphate (naled), and a juvenile growth hormone mimic (methoprene). Acute toxicity (4-day LC50) values ranged from 1.59 to >10 mg/L. Overall, clams were more susceptible to mosquito control insecticides than oysters. Naled was the most toxic compound in oyster larvae, whereas resmethrin was the most toxic compound in clam larvae. Mortality for both species generally increased with chronic insecticide exposure (21-day LC50 values ranged from 0.60 to 9.49 mg/L). Insecticide exposure also caused sublethal effects, including decreased swimming activity after 4 days in larval oysters (4-day EC50 values of 0.60 to 2.33 mg/L) and decreased growth (shell area and weight) in juvenile clams and oysters after 21 days (detected at concentrations ranging from 0.625 to 10 mg/L). Hypoxia, hypercapnia, and a combination of hypoxia and hypercapnia caused mortality in larval clams and increased resmethrin toxicity. These data will benefit both shellfish mariculture operations and environmental resource agencies as they manage the use of mosquito control insecticides near coastal ecosystems. PMID:24531857

  2. High lethality and minimal variation after acute self-poisoning with carbamate insecticides in Sri Lanka – implications for global suicide prevention

    PubMed Central

    Lamb, Thomas; Selvarajah, Liza R.; Mohamed, Fahim; Jayamanne, Shaluka; Gawarammana, Indika; Mostafa, Ahmed; Buckley, Nicholas A.; Roberts, Michael S.; Eddleston, Michael

    2016-01-01

    Abstract Background: Highly hazardous organophosphorus (OP) insecticides are responsible for most pesticide poisoning deaths. As they are removed from agricultural practice, they are often replaced by carbamate insecticides of perceived lower toxicity. However, relatively little is known about poisoning with these insecticides. Methods: We prospectively studied 1288 patients self-poisoned with carbamate insecticides admitted to six Sri Lankan hospitals. Clinical outcomes were recorded for each patient and plasma carbamate concentration measured in a sample to confirm the carbamate ingested. Findings: Patients had ingested 3% carbofuran powder (719), carbosulfan EC25 liquid (25% w/v, 389), or fenobucarb EC50 liquid (50% w/v, 127) formulations, carbamate insecticides of WHO Toxicity Classes Ib, II, and II, respectively. Intubation and ventilation was required for 183 (14.2%) patients while 71 (5.5%) died. Compared with carbofuran, poisoning with carbosulfan or fenobucarb was associated with significantly higher risk of death [carbofuran 2.2%; carbosulfan 11.1%, OR 5.5 (95% CI 3.0–9.8); fenobucarb 6.3%, OR 3.0 (1.2–7.1)] and intubation [carbofuran 6.1%; carbosulfan 27.0%, OR 5.7 (3.9–8.3); fenobucarb 18.9%, OR 3.6 (2.1–6.1)]. The clinical presentation and cause of death did not differ markedly between carbamates. Median time to death was similar: carbofuran 42.3 h (IQR 5.5–67.3), carbosulfan 21.3 h (11.5–71.3), and fenobucarb 25.3 h (17.3–72.1) (p = 0.99); no patients showed delayed onset of toxicity akin to the intermediate syndrome seen after OP insecticide poisoning. For survivors, median duration of intubation was 67.8 h (IQR 27.5–118.8) with no difference in duration between carbamates. Reduced GCS at presentation was associated with worse outcome although some patients with carbosulfan died after presentation with normal GCS. Conclusions: We did not find carbamate insecticide self-poisoning to vary markedly according to the carbamate

  3. Insecticides suppress natural enemies and increase pest damage in cabbage.

    PubMed

    Bommarco, Riccardo; Miranda, Freddy; Bylund, Helena; Björkman, Christer

    2011-06-01

    Intensive use of pesticides is common and increasing despite a growing and historically well documented awareness of the costs and hazards. The benefits from pesticides of increased yields from sufficient pest control may be outweighed by developed resistance in pests and killing of beneficial natural enemies. Other negative effects are human health problems and lower prices because of consumers' desire to buy organic products. Few studies have examined these trade-offs in the field. Here, we demonstrate that Nicaraguan cabbage (Brassica spp.) farmers may suffer economically by using insecticides as they get more damage by the main pest diamondback moth, Plutella xylostella (L.) (Lepidoptera: Plutellidae), at the same time as they spend economic resources on insecticides. Replicated similarly sized cabbage fields cultivated in a standardized manner were either treated with insecticides according common practice or not treated with insecticides over two seasons. Fields treated with insecticides suffered, compared with nontreated fields, equal or, at least in some periods of the seasons, higher diamondback moth pest attacks. These fields also had increased leaf damage on the harvested cabbage heads. Weight and size of the heads were not affected. The farmers received the same price on the local market irrespective of insecticide use. Rates of parasitized diamondback moth were consistently lower in the treated fields. Negative effects of using insecticides against diamondback moth were found for the density of parasitoids and generalist predatory wasps, and tended to affect spiders negatively. The observed increased leaf damages in insecticide-treated fields may be a combined consequence of insecticide resistance in the pest, and of lower predation and parasitization rates from naturally occurring predators that are suppressed by the insecticide applications. The results indicate biological control as a viable and economic alternative pest management strategy

  4. Biogenic Synthesis of Fluorescent Carbon Dots at Ambient Temperature Using Azadirachta indica (Neem) gum.

    PubMed

    Phadke, Chinmay; Mewada, Ashmi; Dharmatti, Roopa; Thakur, Mukeshchand; Pandey, Sunil; Sharon, Madhuri

    2015-07-01

    Synthesis of fluorescent Carbon Dots (CDs) from various carbonaceous materials apparently has acquired lots of interest amongst researchers as the corollary of the properties of CDs; which are subsequently getting unveiled. In this study we report the use of Azadirachta indica (Neem) Gum as a novel natural pre-cursor for synthesis of CDs at room temperature. Water soluble CDs of around 5-8 nm were obtained after treatment of the gum with ethanol and NaOH. These CDs exhibited green fluorescence in UV-light (λ = 365 nm). These CDs were found to be stable, having many bio-linkers attached on their surface, making it suitable for drug attachment and hence can serve as potential candidates for applications like drug delivery vehicles as well as for biosensors.

  5. Chemical compositions of past soluble aerosols reconstructed from NEEM (Greenland) and Dome C (Antarctica) ice cores

    NASA Astrophysics Data System (ADS)

    Oyabu, Ikumi; Iizuka, Yoshinori; Fukui, Manabu; Fischer, Hubertus; Schüpbach, Simon; Gfeller, Gideon; Mulvaney, Robert; Hansson, Margareta

    2015-04-01

    Polar ice core preserve past atmospheric aerosols, which is a useful proxy for understanding the interaction between climate changes and atmospheric aerosols. One useful technique for reconstructing past soluble aerosols from ice core is the determination of dissolved ion species. However, since salts and acids melt into ions, chemical compositions of soluble aerosols in the ice cores have not been cleared. To clarify the temporal variations in the chemical compositions of past soluble aerosols, this study investigated chemical compositions of soluble particles preserved in the NEEM (Greenland) and Dome C (Antarctica) ice cores using new method 'ice-sublimation method'. The ice-sublimation method can extract soluble salts particles as a solid state without melting. The ice core samples are selected from the sections from the last termination (the Last Glacial Maximum (LGM) to Holocene) of Dome C (inland Antarctica) and NEEM ice cores. Using ice-sublimation method, soluble salts particles were extracted. Chemical components of extracted particles were analysed by scanning electron microscope and energy dispersive spectroscopy, and micro-Raman spectroscopy. The major components of soluble salts particles in the Dome C ice core are CaSO4, Na2SO4 and NaCl. The CaSO4 and NaCl fractions were high in the first half of the last termination, whereas the Na2SO4 fraction is high in the latter half of the last termination. The major components of soluble salts particles in the NEEM ice core are CaCO3, CaSO4, NaCl and Na2SO4. The fractions of CaCO3, CaSO4 and NaCl were high in LGM, whereas those of NaCl and Na2SO4 were high in Holocene. The changes in the salts compositions in Dome C ice core are mainly controlled by concentration of terrestrial material (Ca2+). In the first half of the last termination, most of the terrestrial material (CaCO3) reacted with H2SO4 but some of sea-salt (NaCl) was not reacted with H2SO4 due to high Ca2+ concentration. As a result, the CaSO4 and Na

  6. Natural control of bacteria affecting meat quality by a neem (Azadirachta indica A. Juss) cake extract.

    PubMed

    Del Serrone, P; Failla, S; Nicoletti, M

    2015-01-01

    The antibacterial activity of an ethylacetate neem cake extract (NCE) against bacteria that affect meat quality, namely Campylobacter jejuni, Carnobacterium spp., Lactobacillus curvatus, Lactobacillus sakei and Leuconostoc sp., is reported. The antibacterial activity was detected using standardised disc diffusion and macrodilution methods. The bacterial growth inhibition zone ranged from 11.33 ± 0.58 to 22.67 ± 0.58 mm (100 μL NCE). There is significant difference between the growth inhibition zone of NCE and the control (ciprofloxacin 100 μg). The percent of bacterial growth reduction range was 79.75 ± 1.53 to 90.73 ± 1.53 (100 μg NCE) as compared with control (without NCE). NCE in different amounts counteracted the growth of all tested bacteria.

  7. A rare case of toxic optic neuropathy secondary to consumption of neem oil.

    PubMed

    Suresha, A R; Rajesh, P; Anil Raj, K S; Torgal, Radhika

    2013-11-11

    A 35-year-old female was referred to our hospital with bilateral loss of vision of two days duration. She gave history of consumption of about 150 ml of neem oil five days back.Examination revealed no perception of light in both eyes. Both pupils were dilated and sluggishly reacting to light. Her fundus examination showed bilateral hyperemic, edematous discs and also edema extending along the superior and inferior temporal vascular arcade. Magnetic resonance imaging (MRI) scan showed bilateral putaminal regions with altered signal, hypointensities in T1-weighted images, hyperintensities on T2-weighted, images and hyperintense on Fluid Attenuation Inversion Recovery (FLAIR) images suggestive of cytotoxic edema due to tissue hypoxia. Her vision improved to 20/200 in both eyes with treatment after two months. This is the first case report of such nature in the literature to the best of our knowledge. PMID:24212206

  8. A rare case of toxic optic neuropathy secondary to consumption of neem oil.

    PubMed

    Suresha, A R; Rajesh, P; Anil Raj, K S; Torgal, Radhika

    2014-03-01

    A 35-year-old female was referred to our hospital with bilateral loss of vision of two days duration. She gave history of consumption of about 150 ml of neem oil five days back.Examination revealed no perception of light in both eyes. Both pupils were dilated and sluggishly reacting to light. Her fundus examination showed bilateral hyperemic, edematous discs and also edema extending along the superior and inferior temporal vascular arcade. Magnetic resonance imaging (MRI) scan showed bilateral putaminal regions with altered signal, hypointensities in T1-weighted images, hyperintensities on T2-weighted, images and hyperintense on Fluid Attenuation Inversion Recovery (FLAIR) images suggestive of cytotoxic edema due to tissue hypoxia. Her vision improved to 20/200 in both eyes with treatment after two months. This is the first case report of such nature in the literature to the best of our knowledge. PMID:24722271

  9. Natural control of bacteria affecting meat quality by a neem (Azadirachta indica A. Juss) cake extract.

    PubMed

    Del Serrone, P; Failla, S; Nicoletti, M

    2015-01-01

    The antibacterial activity of an ethylacetate neem cake extract (NCE) against bacteria that affect meat quality, namely Campylobacter jejuni, Carnobacterium spp., Lactobacillus curvatus, Lactobacillus sakei and Leuconostoc sp., is reported. The antibacterial activity was detected using standardised disc diffusion and macrodilution methods. The bacterial growth inhibition zone ranged from 11.33 ± 0.58 to 22.67 ± 0.58 mm (100 μL NCE). There is significant difference between the growth inhibition zone of NCE and the control (ciprofloxacin 100 μg). The percent of bacterial growth reduction range was 79.75 ± 1.53 to 90.73 ± 1.53 (100 μg NCE) as compared with control (without NCE). NCE in different amounts counteracted the growth of all tested bacteria. PMID:25272067

  10. Morphological alterations in toxigenic Aspergillus parasiticus exposed to neem (Azadirachta indica) leaf and seed aqueous extracts.

    PubMed

    Razzaghi-Abyaneh, Mehdi; Allameh, Abdolamir; Tiraihi, Taki; Shams-Ghahfarokhi, Masoomeh; Ghorbanian, Mehdi

    2005-06-01

    The mode of action of the extracts prepared from neem plant i.e., Azadirachta indica on aflatoxin formation in toxigenic Aspergillus species is not well understood. Aflatoxin production by A. parasiticus was suppressed depending on the concentration of the plant aqueous extract (0, 1.56, 3.12, 6.25, 12.5, and 50% v/v) added to the culture media at the time of spore inoculation. Aflatoxin production in fungal mycelia grown for 96 h in culture media containing 50% neem leaf and seed extracts was inhibited by approximately 90 and approximately 65% respectively. Under similar conditions, culture media amended with 1.56% of leaf or seed extract caused approximately 23 and approximately 7% inhibition respectively. Mycelial samples exposed to selected concentrations of the plant extract (1.56 or 50% v/v) collected and processed for morphological studies. Semi-thin longitudinal and cross sections prepared from control (untreated) and treated mycelia (1.56% v/v) revealed that alterations are limited to the vacuolation of the mycelial cytoplasm. Nevertheless, exposure to high concentration i.e., 50% v/v of the extract resulted in vacuolation of the mycelial cytoplasm and vesicle deformation causing attenuation of cell wall at variable intervals. Herniation of the cytoplasmic contents that was protruding from the mycelium was associated with deformation of the mycelium. Some mycelia showed a cleft between the cell wall and cytoplasm. Association of aflatoxin production with morphological changes suggest that probably integrity of the cell barriers particularly cell wall is critical in regulation of aflatoxin production and excretion. PMID:15983743

  11. Baculovirus Insecticide Production in Insect Larvae.

    PubMed

    van Beek, Nikolai; Davis, David C

    2016-01-01

    Baculovirus-based insecticides are currently being used worldwide, and new products are in development in many countries. The most dramatic examples of successful baculovirus insecticides are found in soybean in Brazil and cotton in China. Production of baculoviruses is generally done in larvae of a convenient host species, and the level of sophistication varies tremendously between field-collection of infected insects at the one extreme and automated mass manufacturing at the other. Currently, only products with wild type baculoviruses as active ingredients are commercially available. Baculoviruses encoding insecticidal proteins are considered attractive, especially for crops with little tolerance to feeding damage, where speed-of-kill is an important characteristic. Successful field tests with such recombinant baculoviruses have been done in the past, and more tests are ongoing. However, low-cost production of recombinant baculovirus in larvae poses specific problems, due to the short survival time of the production host.In this chapter, benchtop-scale production of two typical baculoviruses is described. First, we describe the production of wild type Helicoverpa zea nucleopolyhedrovirus in bollworm (H. zea) larvae. H. zea larvae are very aggressive and need to be reared in isolation from each other. Second, we describe the production of a recombinant Autographa californica multiple nucleopolyhedrovirus in the non-cannibalistic cabbage looper, Trichoplusia ni. The recombinant baculovirus encodes the insect-specific scorpion toxin LqhIT2. The tetracycline transactivator system enables the production of wild-type quantity and quality product while toxin expression is repressed since normal toxin production would result in premature death of the production host that would limit progeny virus production.

  12. Feeding Deterrence of Cabbage Looper (Lepidoptera: Noctuidae) by 1-Allyloxy-4-Propoxybenzene, Alone and Blended With Neem Extract.

    PubMed

    Cameron, Linda M; Rogers, Megan; Aalhus, Melissa; Seward, Brendan; Yu, Yang; Plettner, Erika

    2014-12-01

    The cabbage looper, Trichoplusia ni (Hübner) (Lepidoptera: Noctuidae), is one of the most damaging insect pests of cabbage (Brassica oleracea variety capitata) and broccoli (B. oleracea variety italica) in North America. Leaf-feeding larvae attack crucifer and vegetable crops in greenhouses and fields. Here, we have studied a synthetic feeding deterrent, 1-allyloxy-4-propoxybenzene, and a botanical deterrent, neem (an extract from seeds of Azadirachta indica A. de Jussieu (Meliaceae)), in leaf disc choice bioassays with T. ni. We tested the two deterrents and the combination, and we found that the blend exhibits synergy between the two deterrents. We also tested the deterrents in assays with whole cabbage plants in ventilated enclosures and found that 1-allyloxy-4-propoxybenzene evaporated and, therefore, in that context addition of 1-allyloxy-4-propoxybenzene to neem did not enhance deterrence against T. ni.

  13. Conifer flavonoid compounds inhibit detoxification enzymes and synergize insecticides.

    PubMed

    Wang, Zhiling; Zhao, Zhong; Cheng, Xiaofei; Liu, Suqi; Wei, Qin; Scott, Ian M

    2016-02-01

    Detoxification by glutathione S-transferases (GSTs) and esterases are important mechanisms associated with insecticide resistance. Discovery of novel GST and esterase inhibitors from phytochemicals could provide potential new insecticide synergists. Conifer tree species contain flavonoids, such as taxifolin, that inhibit in vitro GST activity. The objectives were to test the relative effectiveness of taxifolin as an enzyme inhibitor and as an insecticide synergist in combination with the organophosphorous insecticide, Guthion (50% azinphos-methyl), and the botanical insecticide, pyrethrum, using an insecticide-resistant Colorado potato beetle (CPB) Leptinotarsa decemlineata (Say) strain. Both taxifolin and its isomer, quercetin, increased the mortality of 1(st) instar CPB larvae after 48h when combined with Guthion, but not pyrethrum. Taxifolin had greater in vitro esterase inhibition compared with the commonly used esterase inhibitor, S, S, S-tributyl phosphorotrithioate (DEF). An in vivo esterase and GST inhibition effect after ingestion of taxifolin was measured, however DEF caused a greater suppression of esterase activity. This study demonstrated that flavonoid compounds have both in vitro and in vivo esterase inhibition, which is likely responsible for the insecticide synergism observed in insecticide-resistant CPB. PMID:26821651

  14. Evaluating Coverage and Efficacy of Insecticides to Control Navel Orangeworm

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A novel method employing eggs was designed to assess insecticide coverage in pistachio clusters. Strips of paper towel with known numbers of eggs were pinned into pistachio clusters immediately before insecticide application. The eggs were removed 24-48 hours after application and placed on diet, re...

  15. Effects of organophosphorus insecticides on sage grouse in southeastern Idaho

    USGS Publications Warehouse

    Blus, L.J.; Staley, C.S.; Henny, C.J.; Pendleton, G.W.; Craig, T.H.; Craig, E.H.; Halford, D.K.

    1989-01-01

    Unverified reports indicated die-offs of sage grouse have occurred since the 1970s in southeastern Idaho. Some verification that organophosphorus insecticides were involved was obtained in 1981 and 1983. A radio telemetry study indicated that dimethoate was responsible for most mortality. Methamidophos also acounted for mortality. Sage grouse populations may be adversely affected by organophosphorus insecticides.

  16. Interactions of transgenic Bacillus thuringiensis insecticidal crops with spiders (Araneae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Genetically modified crops expressing insecticidal proteins from Bacillus thuringiensis (Bt) have dramatically increased in acreage since their introduction in the mid-1990’s. Although the insecticidal mechanisms of Bt target specific pests, concerns persist regarding direct and indirect effects on...

  17. ANDROGEN RECEPTOR ANTAGONISM BY THE ORGANOPHOSPHATE INSECTICIDE FENITROTHION

    EPA Science Inventory

    Androgen receptor antagonism by the organophosphate insecticide fenitrothion. Tamura, H., Maness, S.C., Reischmann, K. Dorman, D.C., Gray, L.E., and Gaido, K.W. (2000). Toxicol. Sci.

    Organophosphate insecticides represent one of the most widely used classes of pesticide...

  18. A low concentration of atrazine does not influence the acute toxicity of the insecticide terbufos or its breakdown products to Chironomus tepperi.

    PubMed

    Choung, Catherine B; Hyne, Ross V; Stevens, Mark M; Hose, Grant C

    2010-11-01

    The acute toxicities of the insecticide terbufos and its major breakdown products individually, as binary mixtures, and in combination with the co-applied herbicide atrazine were evaluated using final instar larvae of the midge Chironomus tepperi. Terbufos, terbufos sulfoxide and terbufos sulfone were highly toxic to C. tepperi with mean 96-h EC50 values of 2.13, 3.64 and 2.59 μg/l, respectively. No interaction was observed between atrazine (25 μg/l) and terbufos or its breakdown products while the binary mixture of terbufos sulfoxide and terbufos sulfone exhibited additive toxicity. The high toxicities of terbufos and its environmentally persistent oxidation products suggest that contamination of aquatic systems with this insecticide pose a threat to aquatic organisms whether or not atrazine is also present.

  19. Removal of fluoride by thermally activated carbon prepared from neem (Azadirachta indica) and kikar (Acacia arabica) leaves.

    PubMed

    Kumar, Sunil; Gupta, Asha; Yadav, J P

    2008-03-01

    The present investigation deals with fluoride removal from aqueous solution by thermally activated neem (Azadirachta indica) leaves carbon (ANC) and thermally activated kikar (Acacia arabica) leaves carbon (AKC) adsorbents. In this study neem leaves carbon and kikar leaves carbon prepared by heating the leaves at 400 degrees C in electric furnace was found to be useful for the removal of fluoride. The adsorbents of 0.3 mm and 1.0 mm sizes of neem and kikar leaves carbon was prepared by standard sieve. Batch experiments done to see the fluoride removal properties from synthetic solution of 5 ppm to study the influence of pH, adsorbent dose and contact time on adsorption efficiency The optimum pH was found to be 6 for both adsorbents. The optimum dose was found to be 0.5g/100 ml forANC (activated neem leaves carbon) and 0.7g/100 ml forAKC (activated kikar leaves carbon). The optimum time was found to be one hour for both the adsorbent. It was also found that adsorbent size of 0.3 mm was more efficient than the 1.0 mm size. The adsorption process obeyed Freundlich adsorption isotherm. The straight line of log (qe-q) vs time at ambient temperature indicated the validity of langergren equation consequently first order nature of the process involved in the present study. Results indicate that besides intraparticle diffusion there maybe other processes controlling the rate which may be operating simultaneously. All optimized conditions were applied for removal of fluoride from four natural water samples.

  20. An Operational Framework for Insecticide Resistance Management Planning.

    PubMed

    Chanda, Emmanuel; Thomsen, Edward K; Musapa, Mulenga; Kamuliwo, Mulakwa; Brogdon, William G; Norris, Douglas E; Masaninga, Freddie; Wirtz, Robert; Sikaala, Chadwick H; Muleba, Mbanga; Craig, Allen; Govere, John M; Ranson, Hilary; Hemingway, Janet; Seyoum, Aklilu; Macdonald, Michael B; Coleman, Michael

    2016-05-01

    Arthropod vectors transmit organisms that cause many emerging and reemerging diseases, and their control is reliant mainly on the use of chemical insecticides. Only a few classes of insecticides are available for public health use, and the increased spread of insecticide resistance is a major threat to sustainable disease control. The primary strategy for mitigating the detrimental effects of insecticide resistance is the development of an insecticide resistance management plan. However, few examples exist to show how to implement such plans programmatically. We describe the formulation and implementation of a resistance management plan for mosquito vectors of human disease in Zambia. We also discuss challenges, steps taken to address the challenges, and directions for the future. PMID:27089119

  1. Averting a malaria disaster: will insecticide resistance derail malaria control?

    PubMed

    Hemingway, Janet; Ranson, Hilary; Magill, Alan; Kolaczinski, Jan; Fornadel, Christen; Gimnig, John; Coetzee, Maureen; Simard, Frederic; Roch, Dabiré K; Hinzoumbe, Clément Kerah; Pickett, John; Schellenberg, David; Gething, Peter; Hoppé, Mark; Hamon, Nicholas

    2016-04-23

    World Malaria Day 2015 highlighted the progress made in the development of new methods of prevention (vaccines and insecticides) and treatment (single dose drugs) of the disease. However, increasing drug and insecticide resistance threatens the successes made with existing methods. Insecticide resistance has decreased the efficacy of the most commonly used insecticide class of pyrethroids. This decreased efficacy has increased mosquito survival, which is a prelude to rising incidence of malaria and fatalities. Despite intensive research efforts, new insecticides will not reach the market for at least 5 years. Elimination of malaria is not possible without effective mosquito control. Therefore, to combat the threat of resistance, key stakeholders need to rapidly embrace a multifaceted approach including a reduction in the cost of bringing new resistance management methods to market and the streamlining of associated development, policy, and implementation pathways to counter this looming public health catastrophe. PMID:26880124

  2. Production of Insecticide Degradates in Juices: Implications for Risk Assessment.

    PubMed

    Radford, Samantha A; Panuwet, Parinya; Hunter, Ronald E; Barr, Dana Boyd; Ryan, P Barry

    2016-06-01

    This study was designed to observe the production of degradates of two organophosphorus insecticides and one pyrethroid insecticide in beverages. Purified water, white grape juice, apple juice, and red grape juice were fortified with 500 ng/g malathion, chlorpyrifos, and permethrin, and aliquots were extracted for malathion dicarboxylic acid (MDA), 3,5,6-trichloro-2-pyridinol (TCPy), and 3-phenoxybenzoic acid (3-PBA) several times over a 15 day period of being stored in the dark at 2.5 °C. Overall, first-order kinetics were observed for production of MDA, and statistically significant production of TCPy was also observed. Statistically significant production of 3-phenoxybenzoic acid was not observed. Results indicate that insecticides degrade in food and beverages, and this degradation may lead to preexisting insecticide metabolites in the beverages. Therefore, it is suggested that caution should be exercised when using urinary insecticide metabolites to assess exposure and risk. PMID:27213611

  3. An Operational Framework for Insecticide Resistance Management Planning

    PubMed Central

    Chanda, Emmanuel; Thomsen, Edward K.; Musapa, Mulenga; Kamuliwo, Mulakwa; Brogdon, William G.; Norris, Douglas E.; Masaninga, Freddie; Wirtz, Robert; Sikaala, Chadwick H.; Muleba, Mbanga; Craig, Allen; Govere, John M.; Ranson, Hilary; Hemingway, Janet; Seyoum, Aklilu; Macdonald, Michael B.

    2016-01-01

    Arthropod vectors transmit organisms that cause many emerging and reemerging diseases, and their control is reliant mainly on the use of chemical insecticides. Only a few classes of insecticides are available for public health use, and the increased spread of insecticide resistance is a major threat to sustainable disease control. The primary strategy for mitigating the detrimental effects of insecticide resistance is the development of an insecticide resistance management plan. However, few examples exist to show how to implement such plans programmatically. We describe the formulation and implementation of a resistance management plan for mosquito vectors of human disease in Zambia. We also discuss challenges, steps taken to address the challenges, and directions for the future. PMID:27089119

  4. Botanical insecticides inspired by plant-herbivore chemical interactions.

    PubMed

    Miresmailli, Saber; Isman, Murray B

    2014-01-01

    Plants have evolved a plethora of secondary chemicals to protect themselves against herbivores and pathogens, some of which have been used historically for pest management. The extraction methods used by industry render many phytochemicals ineffective as insecticides despite their bioactivity in the natural context. In this review, we examine how plants use their secondary chemicals in nature and compare this with how they are used as insecticides to understand why the efficacy of botanical insecticides can be so variable. If the commercial production of botanical insecticides is to become a viable pest management option, factors such as production cost, resource availability, and extraction and formulation techniques need be considered alongside innovative application technologies to ensure consistent efficacy of botanical insecticides.

  5. Ecotoxicological study of insecticide effects on arthropods in common bean.

    PubMed

    de Barros, Emerson Cristi; Ventura, Hudson Vaner; Gontijo, Pablo Costa; Pereira, Renata Ramos; Picanço, Marcelo Coutinho

    2015-01-01

    Arthropods are an important group of macroorganisms that work to maintain ecosystem health. Despite the agricultural benefits of chemical control against arthropod pests, insecticides can cause environmental damage. We examined the effects of one and two applications of the insecticides chlorfenapyr (0.18 liters a.i. ha-1) and methamidophos (0.45 liters a.i. ha-1), both independently and in combination, on arthropods in plots of common bean. The experiment was repeated for two growing seasons. Principal response curve, richness estimator, and Shannon-Wiener diversity index analyses were performed. The insecticides generally affected the frequency, richness, diversity, and relative abundance of the arthropods. In addition, the arthropods did not experience recovery after the insecticide applications. The results suggest that the insecticide impacts were sufficiently drastic to eliminate many taxa from the studied common bean plots.

  6. An Operational Framework for Insecticide Resistance Management Planning.

    PubMed

    Chanda, Emmanuel; Thomsen, Edward K; Musapa, Mulenga; Kamuliwo, Mulakwa; Brogdon, William G; Norris, Douglas E; Masaninga, Freddie; Wirtz, Robert; Sikaala, Chadwick H; Muleba, Mbanga; Craig, Allen; Govere, John M; Ranson, Hilary; Hemingway, Janet; Seyoum, Aklilu; Macdonald, Michael B; Coleman, Michael

    2016-05-01

    Arthropod vectors transmit organisms that cause many emerging and reemerging diseases, and their control is reliant mainly on the use of chemical insecticides. Only a few classes of insecticides are available for public health use, and the increased spread of insecticide resistance is a major threat to sustainable disease control. The primary strategy for mitigating the detrimental effects of insecticide resistance is the development of an insecticide resistance management plan. However, few examples exist to show how to implement such plans programmatically. We describe the formulation and implementation of a resistance management plan for mosquito vectors of human disease in Zambia. We also discuss challenges, steps taken to address the challenges, and directions for the future.

  7. Insecticide resistance in the horn fly: alternative control strategies.

    PubMed

    Oyarzún, M P; Quiroz, A; Birkett, M A

    2008-09-01

    The horn fly, Haematobia irritans (Linnaeus 1758) (Diptera: Muscidae) is one of the most widespread and economically important pests of cattle. Although insecticides have been used for fly control, success has been limited because of the development of insecticide resistance in all countries where the horn fly is found. This problem, along with public pressure for insecticide-free food and the prohibitive cost of developing new classes of compounds, has driven the investigation of alternative control methods that minimize or avoid the use of insecticides. This review provides details of the economic impact of horn flies, existing insecticides used for horn fly control and resistance mechanisms. Current research on new methods of horn fly control based on resistant cattle selection, semiochemicals, biological control and vaccines is also discussed.

  8. Ecotoxicological Study of Insecticide Effects on Arthropods in Common Bean

    PubMed Central

    de Barros, Emerson Cristi; Ventura, Hudson Vaner; Gontijo, Pablo Costa; Pereira, Renata Ramos; Picanço, Marcelo Coutinho

    2015-01-01

    Arthropods are an important group of macroorganisms that work to maintain ecosystem health. Despite the agricultural benefits of chemical control against arthropod pests, insecticides can cause environmental damage. We examined the effects of one and two applications of the insecticides chlorfenapyr (0.18 liters a.i. ha-1) and methamidophos (0.45 liters a.i. ha-1), both independently and in combination, on arthropods in plots of common bean. The experiment was repeated for two growing seasons. Principal response curve, richness estimator, and Shannon–Wiener diversity index analyses were performed. The insecticides generally affected the frequency, richness, diversity, and relative abundance of the arthropods. In addition, the arthropods did not experience recovery after the insecticide applications. The results suggest that the insecticide impacts were sufficiently drastic to eliminate many taxa from the studied common bean plots. PMID:25700537

  9. Insecticidal sesquiterpene from Alpinia oxyphylla against Drosophila melanogaster.

    PubMed

    Miyazawa, M; Nakamura, Y; Ishikawa, Y

    2000-08-01

    In the course of screening for novel naturally occurring insecticides from Chinese crude drugs, an MeOH extract of Alpinia oxyphylla was found to possess insecticidal activity against larvae of Drosophila melanogaster Meigen. From the extract, an insecticidal compound was isolated by bioassay-guided fractionation and identified as nootkatone (1) by GC, GC-MS, and (1)H and (13)C NMR spectroscopy. In bioassays for insecticidal activity, 1 showed an LC(50) value of 11.5 micromol/mL of diet against larvae of D. melanogaster and an LD(50) value of 96 microg/adult against adults. Epinootkatol (1A), however, showed slight insecticidal activity in both assays, indicating that the carbonyl group at the 2-position in 1 was the important function for enhanced activity of 1. PMID:10956162

  10. Averting a malaria disaster: will insecticide resistance derail malaria control?

    PubMed

    Hemingway, Janet; Ranson, Hilary; Magill, Alan; Kolaczinski, Jan; Fornadel, Christen; Gimnig, John; Coetzee, Maureen; Simard, Frederic; Roch, Dabiré K; Hinzoumbe, Clément Kerah; Pickett, John; Schellenberg, David; Gething, Peter; Hoppé, Mark; Hamon, Nicholas

    2016-04-23

    World Malaria Day 2015 highlighted the progress made in the development of new methods of prevention (vaccines and insecticides) and treatment (single dose drugs) of the disease. However, increasing drug and insecticide resistance threatens the successes made with existing methods. Insecticide resistance has decreased the efficacy of the most commonly used insecticide class of pyrethroids. This decreased efficacy has increased mosquito survival, which is a prelude to rising incidence of malaria and fatalities. Despite intensive research efforts, new insecticides will not reach the market for at least 5 years. Elimination of malaria is not possible without effective mosquito control. Therefore, to combat the threat of resistance, key stakeholders need to rapidly embrace a multifaceted approach including a reduction in the cost of bringing new resistance management methods to market and the streamlining of associated development, policy, and implementation pathways to counter this looming public health catastrophe.

  11. Alpha- and EC-decay measurements of 257Rf

    NASA Astrophysics Data System (ADS)

    Heßberger, F. P.; Antalic, S.; Mistry, A. K.; Ackermann, D.; Andel, B.; Block, M.; Kalaninova, Z.; Kindler, B.; Kojouharov, I.; Laatiaoui, M.; Lommel, B.; Piot, J.; Vostinar, M.

    2016-07-01

    Alpha- and Electron capture (EC) decay properties of 257 Rf were investigated by measuring α - γ coincidences and correlations between conversion electrons (CE) emitted during the process of EC decay of 257Rf and α decays of the daughter isotope 257Lr. So far, previously unobserved α (8296 keV)- γ (557 keV) coincidences were measured and interpreted as decays of 257mRf ( 11/2-[725] into the 7/2-[743] level in 253No. A search of delayed coincidences between α particles and signals at E ≤ 1000 keV, which are interpreted as being due to CE emission, revealed a clear correlation between CE and α particles from the decay of 257Lr, which is regarded as a direct proof of the EC decay of 257gRf and 257mRf.

  12. The bioavailable iron in NEEM ice core related to Asian dust records over the past 110 kyr

    NASA Astrophysics Data System (ADS)

    Xiao, Cunde

    2016-04-01

    The mineral dust can indirectly affect climate by supplying iron and other essential bioavailable elements into ocean. In this study, we present dissolved iron (DFe) and total dissolved iron (TDFe) concentrations in NEEM ice core over the past 110 kyr B.P. The concentrations of bioavailable reactive element Fe have good positive correlation with the concentrations of dust and Ca2+ in NEEM ice core, while show significantly negative relationship with δ18O and CO2 concentration. The ratios of DFe/TDFe are higher in warm periods (Holocene and last interglacial) than in cold period (LGM), indicating the iron-biological pump effect is more significant in warm periods than that in cold periods, this result may provide a new insight for reevaluating the iron hypothesis over glacial/interglacial periods. Our study also shows that the iron flux changes between NEEM ice core and Asian loess records are good consistent with the northern Hemisphere summer insolation. These results emphasize that the variability of Fe flux is most likely driven by solar radiation and dust in northern hemisphere.

  13. The impact of ice layers on gas transport through firn at the North Greenland Eemian Ice Drilling (NEEM) site, Greenland

    NASA Astrophysics Data System (ADS)

    Keegan, K.; Albert, M. R.; Baker, I.

    2014-10-01

    Typically, gas transport through firn is modeled in the context of an idealized firn column. However, in natural firn, imperfections are present, which can alter transport dynamics and therefore reduce the accuracy of reconstructed climate records. For example, ice layers have been found in several firn cores collected in the polar regions. Here, we examined the effects of two ice layers found in a NEEM, Greenland firn core on gas transport through the firn. These ice layers were found to have permeability values of 3.0 and 4.0 × 10-10 m2, and are therefore not impermeable layers. However, the shallower ice layer was found to be significantly less permeable than the surrounding firn, and can therefore retard gas transport. Large closed bubbles were found in the deeper ice layer, which will have an altered gas composition than that expected because they were closed near the surface after the water phase was present. The bubbles in this layer represent 12% of the expected closed porosity of this firn layer after the firn-ice transition depth is reached, and will therefore bias the future ice core gas record. The permeability and thickness of the ice layers at the North Greenland Eemian Ice Drilling (NEEM) site suggest that they do not disrupt the firn-air concentration profiles and that they do not need to be accounted for in gas transport models at NEEM.

  14. Neem (Azadirachta indica L.) leaf extract deteriorates oocyte quality by inducing ROS-mediated apoptosis in mammals.

    PubMed

    Chaube, Shail K; Shrivastav, Tulsidas G; Tiwari, Meenakshi; Prasad, Shilpa; Tripathi, Anima; Pandey, Ajai K

    2014-01-01

    Neem (Azadirachta indica L.) leaf has been widely used in ayurvedic system of medicine for fertility regulation for a long time. The molecular mechanism by which neem leaf regulates female fertility remains poorly understood. Animal studies suggest that aqueous neem leaf extract (NLE) induces reactive oxygen species (ROS) - mediated granulosa cell apoptosis. Granulosa cell apoptosis deprives oocytes from nutrients, survival factors and cell cycle proteins required for the achievement of meiotic competency of follicular oocytes prior to ovulation. Under this situation, follicular oocyte becomes more susceptible towards apoptosis after ovulation. The increased level of hydrogen peroxide (H2O2) inside the follicular fluid results in the transfer of H2O2 from follicular fluid to the oocyte. The increased level of H2O2 induces p53 activation and over expression of Bax protein that modulates mitochondrial membrane potential and trigger cytochrome c release. The increased cytosolic cytochrome c level induces caspase-9 and caspase-3 activities that trigger destruction of structural and specific proteins leading to DNA fragmentation and thereby oocyte apoptosis. Based on these animal studies, we propose that NLE induces generation of ROS and mitochondria-mediated apoptosis both in granulosa cells as well as in follicular oocyte. The induction of apoptosis deteriorates oocyte quality and thereby limits reproductive outcome in mammals.

  15. Antiviral activity and mode of action of extracts from neem seed kernel against duck plague virus in vitro1.

    PubMed

    Xu, J; Song, X; Yin, Z Q; Cheng, A C; Jia, R Y; Deng, Y X; Ye, K C; Shi, C F; Lv, C; Zhang, W

    2012-11-01

    Four fractions obtained from alcohol extracts of neem (Azadirachta indica) seed kernel by column chromatography were investigated for antivirus activity against the duck plague virus (DPV) in vitro. Duck embryo fibroblasts (DEF) infected with DPV were treated with the neem seed kernel extracts, and the effect of antivirus was judged by 3-(4,5)-dimethylthiahiazo (-z-y1)-3,5-di-phenytetrazoliumromide colorimetric method assay and direct immunofluorescence assay. The mode of action was tested by the plaque reduction assay. The results showed that fractions 1 to 3 were inactive. The median inhibitory concentration (IC(50)) of fraction 4 was 10.9 μg/mL and inhibited the virus protein expression in the direct immunofluorescence assay. In the plaque reduction assay, fraction 4 could significantly reduce the number of plaques compared with the negative control (P < 0.01) in all modes of action. This study indicated that the fourth fraction obtained from neem seed kernel could improve the viability of infected cells, and reduce the cytopathic effects caused by DPV and the amount of the virus protein expressed in virus-infected cells. The antiviral activity works in the whole process of virus infecting the normal cells. PMID:23091135

  16. Can nutrients mask community responses to insecticide mixtures?

    PubMed

    Alexander, Alexa C; Luis, Ana T; Culp, Joseph M; Baird, Donald J; Cessna, Allan J

    2013-09-01

    The ecological effect of simultaneous exposure to two nutrient gradients, three insecticides and different predator intensities was investigated over a 3-week period in 80 outdoor, artificial streams using field-collected benthic invertebrates. The experimental design consisted of a 2 × 5 factorial structure with two nutrient levels (oligotrophic or mesotrophic) and five concentrations of the ternary insecticide mixture consisting of the insecticides (chlorpyrifos, dimethoate and imidacloprid). Equivalent toxic unit doses were summed to create a ternary insecticide dose (e.g., 0.1 + 0.1 + 0.1 = 0.3 TU) resulting in a range of ternary insecticide mixture toxicity (i.e., control groundwater, 0.3, 0.6, 0.9 and 1.2 TU). Two genera of insect predators, Gomphus spp. (Odonata) and Agnetina spp. (Plecoptera) were also added into each replicate stream, at densities and sizes comparable to those found at our collection site, to evaluate how the contribution of predators may change in nutrient limited (oligotrophic) versus amended (mesotrophic) systems. We describe a causal mechanism whereby the combined action of nutrients and insecticides reshaped aquatic community structure by interacting through multiple pathways. Specifically, mesotrophic conditions reduced the toxic effects of ternary insecticide mixtures for aquatic insects which, in some cases, appeared to increase abundance of aquatic insects. However, higher levels of insecticides in mesotrophic streams negated this effect and were even more toxic; for example, to aquatic insect grazers than the same insecticide doses in oligotrophic treatment levels. Effects of predators were only significant in oligotrophic streams. Evidence is provided as to how nutrient and contaminant interactions can greatly complicate the assessment of community level responses to insecticide mixtures due to direct and indirect effects of the resulting changes in the density of different genera and functional feeding groups within a

  17. Risks of neonicotinoid insecticides to honeybees.

    PubMed

    Fairbrother, Anne; Purdy, John; Anderson, Troy; Fell, Richard

    2014-04-01

    The European honeybee, Apis mellifera, is an important pollinator of agricultural crops. Since 2006, when unexpectedly high colony losses were first reported, articles have proliferated in the popular press suggesting a range of possible causes and raising alarm over the general decline of bees. Suggested causes include pesticides, genetically modified crops, habitat fragmentation, and introduced diseases and parasites. Scientists have concluded that multiple factors in various combinations-including mites, fungi, viruses, and pesticides, as well as other factors such as reduction in forage, poor nutrition, and queen failure-are the most probable cause of elevated colony loss rates. Investigators and regulators continue to focus on the possible role that insecticides, particularly the neonicotinoids, may play in honeybee health. Neonicotinoid insecticides are insect neurotoxicants with desirable features such as broad-spectrum activity, low application rates, low mammalian toxicity, upward systemic movement in plants, and versatile application methods. Their distribution throughout the plant, including pollen, nectar, and guttation fluids, poses particular concern for exposure to pollinators. The authors describe how neonicotinoids interact with the nervous system of honeybees and affect individual honeybees in laboratory situations. Because honeybees are social insects, colony effects in semifield and field studies are discussed. The authors conclude with a review of current and proposed guidance in the United States and Europe for assessing the risks of pesticides to honeybees. PMID:24692231

  18. Risks of neonicotinoid insecticides to honeybees

    PubMed Central

    Fairbrother, Anne; Purdy, John; Anderson, Troy; Fell, Richard

    2014-01-01

    The European honeybee, Apis mellifera, is an important pollinator of agricultural crops. Since 2006, when unexpectedly high colony losses were first reported, articles have proliferated in the popular press suggesting a range of possible causes and raising alarm over the general decline of bees. Suggested causes include pesticides, genetically modified crops, habitat fragmentation, and introduced diseases and parasites. Scientists have concluded that multiple factors in various combinations—including mites, fungi, viruses, and pesticides, as well as other factors such as reduction in forage, poor nutrition, and queen failure—are the most probable cause of elevated colony loss rates. Investigators and regulators continue to focus on the possible role that insecticides, particularly the neonicotinoids, may play in honeybee health. Neonicotinoid insecticides are insect neurotoxicants with desirable features such as broad-spectrum activity, low application rates, low mammalian toxicity, upward systemic movement in plants, and versatile application methods. Their distribution throughout the plant, including pollen, nectar, and guttation fluids, poses particular concern for exposure to pollinators. The authors describe how neonicotinoids interact with the nervous system of honeybees and affect individual honeybees in laboratory situations. Because honeybees are social insects, colony effects in semifield and field studies are discussed. The authors conclude with a review of current and proposed guidance in the United States and Europe for assessing the risks of pesticides to honeybees. PMID:24692231

  19. Risks of neonicotinoid insecticides to honeybees.

    PubMed

    Fairbrother, Anne; Purdy, John; Anderson, Troy; Fell, Richard

    2014-04-01

    The European honeybee, Apis mellifera, is an important pollinator of agricultural crops. Since 2006, when unexpectedly high colony losses were first reported, articles have proliferated in the popular press suggesting a range of possible causes and raising alarm over the general decline of bees. Suggested causes include pesticides, genetically modified crops, habitat fragmentation, and introduced diseases and parasites. Scientists have concluded that multiple factors in various combinations-including mites, fungi, viruses, and pesticides, as well as other factors such as reduction in forage, poor nutrition, and queen failure-are the most probable cause of elevated colony loss rates. Investigators and regulators continue to focus on the possible role that insecticides, particularly the neonicotinoids, may play in honeybee health. Neonicotinoid insecticides are insect neurotoxicants with desirable features such as broad-spectrum activity, low application rates, low mammalian toxicity, upward systemic movement in plants, and versatile application methods. Their distribution throughout the plant, including pollen, nectar, and guttation fluids, poses particular concern for exposure to pollinators. The authors describe how neonicotinoids interact with the nervous system of honeybees and affect individual honeybees in laboratory situations. Because honeybees are social insects, colony effects in semifield and field studies are discussed. The authors conclude with a review of current and proposed guidance in the United States and Europe for assessing the risks of pesticides to honeybees.

  20. ECS: efficient communication scheduling for underwater sensor networks.

    PubMed

    Hong, Lu; Hong, Feng; Guo, Zhongwen; Li, Zhengbao

    2011-01-01

    TDMA protocols have attracted a lot of attention for underwater acoustic sensor networks (UWSNs), because of the unique characteristics of acoustic signal propagation such as great energy consumption in transmission, long propagation delay and long communication range. Previous TDMA protocols all allocated transmission time to nodes based on discrete time slots. This paper proposes an efficient continuous time scheduling TDMA protocol (ECS) for UWSNs, including the continuous time based and sender oriented conflict analysis model, the transmission moment allocation algorithm and the distributed topology maintenance algorithm. Simulation results confirm that ECS improves network throughput by 20% on average, compared to existing MAC protocols.

  1. Genes and proteins of Escherichia coli (GenProtEc).

    PubMed

    Riley, M; Space, D B

    1996-01-01

    GenProtEc is a database of Escherichia coli genes and their gene products, classified by type of function and physiological role and with citations to the literature for each. Also present are data on sequence similarities among E.coli proteins with PAM values, percent identity of amino acids, length of alignment and percent aligned. The database is available as a PKZip file by ftp from mbl.edu/pub/ecoli.exe. The program runs under MS-DOS on IMB-compatible machines. GenProtEc can also be accessed through the World Wide Web at URL http://mbl.edu/html/ecoli.html. PMID:8594596

  2. On the neutrinoless double β{sup +}/EC decays

    SciTech Connect

    Suhonen, Jouni

    2013-12-30

    The neutrinoless double positron-emission/electron-capture (0νβ{sup +}/EC) decays are studied for the magnitudes of the involved nuclear matrix elements (NMEs). Decays to the ground state, 0{sub gs}{sup +}, and excited 0{sup +} states are discussed. The participant many-body wave functions are evaluated in the framework of the quasiparticle random-phase approximation (QRPA). Effective, G-matrix-derived nuclear forces are used in realistic single-particle model spaces. The channels β{sup +}β{sup +}, β{sup +}EC, and the resonant neutrinoless double electron capture (R0νECEC) are discussed.

  3. ECS: Efficient Communication Scheduling for Underwater Sensor Networks

    PubMed Central

    Hong, Lu; Hong, Feng; Guo, Zhongwen; Li, Zhengbao

    2011-01-01

    TDMA protocols have attracted a lot of attention for underwater acoustic sensor networks (UWSNs), because of the unique characteristics of acoustic signal propagation such as great energy consumption in transmission, long propagation delay and long communication range. Previous TDMA protocols all allocated transmission time to nodes based on discrete time slots. This paper proposes an efficient continuous time scheduling TDMA protocol (ECS) for UWSNs, including the continuous time based and sender oriented conflict analysis model, the transmission moment allocation algorithm and the distributed topology maintenance algorithm. Simulation results confirm that ECS improves network throughput by 20% on average, compared to existing MAC protocols. PMID:22163775

  4. Effects of spiracle-blocking insecticides and microbial insecticides on the predator mirid bug, Nesidiocoris tenuis (reuter) (heteroptera: miridae).

    PubMed

    Nakaishi, K; Arakawa, R

    2011-11-01

    Spiracle-blocking insecticides and microbial insecticides are widely used for Integrated Pest Management (IPM) in Japan while Nesidiocoris tenuis is used for the control of thrips and whiteflies in Kochi Prefecture, Japan. However, the effects of the insecticides mentioned above on N. tenuis were unclear. This study investigated the effects of five spiracle-blocking insecticides and two microbial insecticides on the nymphs and adults ofN. tenuis. Propylene glycol fatty acid monoester was slightly harmful to both the nymphs and adults. Hydroxypropyl starch was slightly harmful to the nymphs, while sodium oleate was slightly harmful to the adults. Decanoyloctanoylglycerol and hydrogenated starch hydrolysate were not harmful to either the nymphs or adults. Beauveria bassiana was extremely harmful to the adults and was moderately harmful to the nymphs. Lecanicillium muscarium was slightly harmful to the adults. Therefore, decanoyloctanoylglycerol and hydrogenated starch hydrolysate can be used in combination with N. tenuis to establish an IPM program.

  5. Morphological alterations in the synganglion and integument of Rhipicephalus sanguineus ticks exposed to aqueous extracts of neem leaves (Azadirachta indica A. JUSS).

    PubMed

    Remedio, R N; Nunes, P H; Anholeto, L A; Camargo-Mathias, M I

    2014-12-01

    Currently, the necessity of controlling infestation by ticks, especially by Rhipicephalus sanguineus, has led researchers and public health managers around the world to search for new and more efficient control methods. This way, we can highlight neem (Azadirachta indica A. Juss) leaf, bark, and seed extracts, which have been very effective on tick control, and moreover causing less damage to the environment and to the host. This study showed the potential of neem as a control method for R. sanguineus through morphological and morphometric evaluation of the integument and synganglion of females, in semiengorged stage. To attain this, routine techniques of optical microscopy, scanning electron microscopy and morphometry of the cuticle and subcuticle of the integument were applied. Expressive morphological alterations were observed in both organs, presenting a dose-dependent effect. Integument epithelial cells and nerve cells of the synganglion showed signs of cell vacuolation, dilated intercellular boundaries, and cellular disorganization, alterations not previously reported in studies with neem. In addition, variations in subcuticle thickness were also observed. In general, the effects of neem are multiple, and affect the morphology and physiology of target animals in various ways. The results presented in this work are the first evidence of its effects in the coating and nervous system of ticks, thus allowing an indication of neem aqueous extracts as a potential control method of the brown dog tick and opening new perspectives on acaricide use.

  6. A solvent induced crystallisation method to imbue bioactive ingredients of neem oil into the compact structure of poly (ethylene terephthalate) polyester.

    PubMed

    Ali, Wazed; Sultana, Parveen; Joshi, Mangala; Rajendran, Subbiyan

    2016-07-01

    Neem oil, a natural antibacterial agent from neem tree (Azadarichtaindica) has been used to impart antibacterial activity to polyester fabrics. Solvent induced polymer modification method was used and that facilitated the easy entry of neem molecules into the compact structure of polyethylene terephthalate (PET) polyester. The polyester fabric was treated with trichloroacetic acid-methylene chloride (TCAMC) solvent system at room temperature prior to treatment with neem oil. The concentration of TCAMC and the treatment time were optimised. XRD and SEM results showed that the TCAMC treatment causes polymer modification and morphological changes in the PET polyester. Antibacterial activity of TCAMC pre-treated and neem-oil-treated polyester fabric was tested using AATCC qualitative and quantitative methods. Both Gram-positive and Gram-negative organisms were used to determine the antimicrobial activity. It was observed that the treated fabric registers substantial antimicrobial activity against both the Staphylococcus aureus (Gram-positive) and the Escherichia coli (Gram-negative) and the effect increases with the increase in concentration of TCAMC treatment. The antibacterial effect remains substantial even after 25 launderings. A kinetic growth study involving the effect of antibacterial activity at various incubation times was carried out.

  7. Morphological alterations in the synganglion and integument of Rhipicephalus sanguineus ticks exposed to aqueous extracts of neem leaves (Azadirachta indica A. JUSS).

    PubMed

    Remedio, R N; Nunes, P H; Anholeto, L A; Camargo-Mathias, M I

    2014-12-01

    Currently, the necessity of controlling infestation by ticks, especially by Rhipicephalus sanguineus, has led researchers and public health managers around the world to search for new and more efficient control methods. This way, we can highlight neem (Azadirachta indica A. Juss) leaf, bark, and seed extracts, which have been very effective on tick control, and moreover causing less damage to the environment and to the host. This study showed the potential of neem as a control method for R. sanguineus through morphological and morphometric evaluation of the integument and synganglion of females, in semiengorged stage. To attain this, routine techniques of optical microscopy, scanning electron microscopy and morphometry of the cuticle and subcuticle of the integument were applied. Expressive morphological alterations were observed in both organs, presenting a dose-dependent effect. Integument epithelial cells and nerve cells of the synganglion showed signs of cell vacuolation, dilated intercellular boundaries, and cellular disorganization, alterations not previously reported in studies with neem. In addition, variations in subcuticle thickness were also observed. In general, the effects of neem are multiple, and affect the morphology and physiology of target animals in various ways. The results presented in this work are the first evidence of its effects in the coating and nervous system of ticks, thus allowing an indication of neem aqueous extracts as a potential control method of the brown dog tick and opening new perspectives on acaricide use. PMID:25130979

  8. A solvent induced crystallisation method to imbue bioactive ingredients of neem oil into the compact structure of poly (ethylene terephthalate) polyester.

    PubMed

    Ali, Wazed; Sultana, Parveen; Joshi, Mangala; Rajendran, Subbiyan

    2016-07-01

    Neem oil, a natural antibacterial agent from neem tree (Azadarichtaindica) has been used to impart antibacterial activity to polyester fabrics. Solvent induced polymer modification method was used and that facilitated the easy entry of neem molecules into the compact structure of polyethylene terephthalate (PET) polyester. The polyester fabric was treated with trichloroacetic acid-methylene chloride (TCAMC) solvent system at room temperature prior to treatment with neem oil. The concentration of TCAMC and the treatment time were optimised. XRD and SEM results showed that the TCAMC treatment causes polymer modification and morphological changes in the PET polyester. Antibacterial activity of TCAMC pre-treated and neem-oil-treated polyester fabric was tested using AATCC qualitative and quantitative methods. Both Gram-positive and Gram-negative organisms were used to determine the antimicrobial activity. It was observed that the treated fabric registers substantial antimicrobial activity against both the Staphylococcus aureus (Gram-positive) and the Escherichia coli (Gram-negative) and the effect increases with the increase in concentration of TCAMC treatment. The antibacterial effect remains substantial even after 25 launderings. A kinetic growth study involving the effect of antibacterial activity at various incubation times was carried out. PMID:27127070

  9. Susceptibility of Cimex lectularius (Hemiptera: Cimicidae) to pyrethroid insecticides and to insecticidal dusts with or without pyrethroid insecticides.

    PubMed

    Anderson, John F; Cowles, Richard S

    2012-10-01

    Relative increases of bed bug, Cimex lectularius L., populations are probably due in large measure to their resistance to pyrethroids, which have been used extensively against urban pests. A Connecticut population of bed bugs was assessed for sensitivity to pyrethroids and exposed to commonly-used commercial insecticides applied to various substrates on which the residues were allowed to age for 0-24 wk. Type I and type II pyrethroids differed in toxicity when applied at a high dosage (1 microg) per bed bug. Some type II pyrethroids (cyfluthrin, lambda-cyhalothrin, cis-cypermethrin, and deltamethrin) caused > 80% mortality, whereas exposure to type I pyrethroids caused < 5% mortality over 72 h (with one exception, pyrethrins caused 23% mortality). Dust products were not affected by residue aging; mortality response over time of exposure closely fit (R2 > 0.95) an exponential rise to a maximum model from which the survival half-life (S1/2) was calculated directly. Tempo Dust (Bayer Environmental Science, Montvale, NJ) killed bed bugs relatively quickly, as did Syloid 244 (Grace Davison, Columbia, MD) and Drione (Bayer Environmental Science, Montvale, NJ) on hardboard and mattress fabric substrates (S1/2 < 1 d); DeltaDust (Bayer Environmental Science, Montvale, NJ) provided a relatively slow kill (S1/2 approximately equal to 3.5 d). The sprayable pyrethroids, Cyonara 9.7 (Insecticide Control solutions, Pasadena, TX) and D-Force HPX Aerosol 0.06% (Waterbury Companies, Waterbury, CT), displayed reduced residual toxicity as they aged; the mortality was < 50% on some substrates after 4 d. Desiccant dusts, with their physical mode of action and long residual activity, appear to be superior to sprayable pyrethroid products for killing bed bugs.

  10. Measuring Eating Competence: Psychometric Properties and Validity of the ecSatter Inventory

    ERIC Educational Resources Information Center

    Lohse, Barbara; Satter, Ellyn; Horacek, Tanya; Gebreselassie, Tesfayi; Oakland, Mary Jane

    2007-01-01

    Objective: Assess validity of the ecSatter Inventory (ecSI) to measure eating competence (EC). Design: Concurrent administration of ecSI with validated measures of eating behaviors using on-line and paper-pencil formats. Setting: The on-line survey was completed by 370 participants; 462 completed the paper version. Participants: Participants…

  11. How to make evolution-proof insecticides for malaria control.

    PubMed

    Read, Andrew F; Lynch, Penelope A; Thomas, Matthew B

    2009-04-01

    Insecticides are one of the cheapest, most effective, and best proven methods of controlling malaria, but mosquitoes can rapidly evolve resistance. Such evolution, first seen in the 1950s in areas of widespread DDT use, is a major challenge because attempts to comprehensively control and even eliminate malaria rely heavily on indoor house spraying and insecticide-treated bed nets. Current strategies for dealing with resistance evolution are expensive and open ended, and their sustainability has yet to be demonstrated. Here we show that if insecticides targeted old mosquitoes, and ideally old malaria-infected mosquitoes, they could provide effective malaria control while only weakly selecting for resistance. This alone would greatly enhance the useful life span of an insecticide. However,such weak selection for resistance can easily be overwhelmed if resistance is associated with fitness costs. In that case, late-life-acting insecticides would never be undermined by mosquito evolution.We discuss a number of practical ways to achieve this, including different use of existing chemical insecticides,biopesticides, and novel chemistry. Done right, a one-off investment in a single insecticide would solve the problem of mosquito resistance forever.

  12. Simulating cholinesterase inhibition in birds caused by dietary insecticide exposure

    USGS Publications Warehouse

    Corson, M.S.; Mora, M.A.; Grant, W.E.

    1998-01-01

    We describe a stochastic simulation model that simulates avian foraging in an agricultural landscape to evaluate factors affecting dietary insecticide exposure and to predict post-exposure cholinesterase (ChE) inhibition. To evaluate the model, we simulated published field studies and found that model predictions of insecticide decay and ChE inhibition reasonably approximated most observed results. Sensitivity analysis suggested that foraging location usually influenced ChE inhibition more than diet preferences or daily intake rate. Although organophosphorus insecticides usually caused greater inhibition than carbamate insecticides, insecticide toxicity appeared only moderately important. When we simulated impact of heavy insecticide applications during breeding seasons of 15 wild bird species, mean maximum ChE inhibition in most species exceeded 20% at some point. At this level of inhibition, birds may experience nausea and/or may exhibit minor behavioral changes. Simulated risk peaked in April-May and August-September and was lowest in July. ChE inhibition increased with proportion of vegetation in the diet. This model, and ones like it, may help predict insecticide exposure of and sublethal ChE inhibition in grassland animals, thereby reducing dependence of ecological risk assessments on field studies alone.

  13. Insecticides induced biochemical changes in freshwater microalga Chlamydomonas mexicana.

    PubMed

    Kumar, Muthukannan Satheesh; Kabra, Akhil N; Min, Booki; El-Dalatony, Marwa M; Xiong, Jiuqiang; Thajuddin, Nooruddin; Lee, Dae Sung; Jeon, Byong-Hun

    2016-01-01

    The effect of insecticides (acephate and imidacloprid) on a freshwater microalga Chlamydomonas mexicana was investigated with respect to photosynthetic pigments, carbohydrate and protein contents, fatty acids composition and induction of stress indicators including proline, superoxide dismutase (SOD) and catalase (CAT). C. mexicana was cultivated with 1, 5, 10, 15, 20 and 25 mg L(-1) of acephate and imidacloprid. The microalga growth increased with increasing concentrations of both insecticides up to 15 mg L(-1), beyond which the growth declined compared to control condition (without insecticides). C. mexicana cultivated with 15 mg L(-1) of both insecticides for 12 days was used for further analysis. The accumulation of photosynthetic pigments (chlorophyll and carotenoids), carbohydrates and protein was decreased in the presence of both insecticides. Acephate and imidacloprid induced the activities of superoxide dismutase (SOD) and catalase (CAT) and increased the concentration of proline in the microalga, which play a defensive role against various environmental stresses. Fatty acid analysis revealed that the fraction of polyunsaturated fatty acids decreased on exposure to both insecticides. C. mexicana also promoted 25 and 21% removal of acephate and imidacloprid, respectively. The biochemical changes in C. mexicana on exposure to acephate and imidacloprid indicate that the microalga undergoes an adaptive change in response to the insecticide-induced oxidative stress.

  14. NARSTO EPA SS LOS ANGELES AETHALOMETER EC DATA

    Atmospheric Science Data Center

    2014-04-25

    NARSTO EPA SS LOS ANGELES AETHALOMETER EC DATA Project Title:  NARSTO Discipline:  ... Carbonaceous Aerosols Particulate Matter Order Data:  ASDC Order Tool:   Order Data Guide Documents:  ... Earth Related Data:  Environmental Protection Agency Supersites Los Angeles, California SCAR-B ...

  15. Award of EC Television Prize for Broadcasts on Vocational Training.

    ERIC Educational Resources Information Center

    European Centre for the Development of Vocational Training, Berlin (West Germany).

    The European Centre for the Development of Vocational Training (CEDEFOP) is endeavoring to encourage television to provide more and better information on vocational and continuing education in the European Community (EC). Therefore, it held its first competition to award prizes for broadcasts presenting information on vocational training,…

  16. EcSL: Teaching Economics as a Second Language.

    ERIC Educational Resources Information Center

    Crowe, Richard

    Hazard Community College, in Kentucky, has implemented a new instructional methodology for economics courses called Economics as a Second Language (EcSL). This teaching approach, based on the theory of Rendigs Fel that the best model for learning economics is the foreign language classroom, utilizes strategies similar to those employed in…

  17. Quantitative structure-activity relationship (QSAR) for insecticides: development of predictive in vivo insecticide activity models.

    PubMed

    Naik, P K; Singh, T; Singh, H

    2009-07-01

    Quantitative structure-activity relationship (QSAR) analyses were performed independently on data sets belonging to two groups of insecticides, namely the organophosphates and carbamates. Several types of descriptors including topological, spatial, thermodynamic, information content, lead likeness and E-state indices were used to derive quantitative relationships between insecticide activities and structural properties of chemicals. A systematic search approach based on missing value, zero value, simple correlation and multi-collinearity tests as well as the use of a genetic algorithm allowed the optimal selection of the descriptors used to generate the models. The QSAR models developed for both organophosphate and carbamate groups revealed good predictability with r(2) values of 0.949 and 0.838 as well as [image omitted] values of 0.890 and 0.765, respectively. In addition, a linear correlation was observed between the predicted and experimental LD(50) values for the test set data with r(2) of 0.871 and 0.788 for both the organophosphate and carbamate groups, indicating that the prediction accuracy of the QSAR models was acceptable. The models were also tested successfully from external validation criteria. QSAR models developed in this study should help further design of novel potent insecticides.

  18. Induced tolerance from a sublethal insecticide leads to cross-tolerance to other insecticides.

    PubMed

    Hua, Jessica; Jones, Devin K; Relyea, Rick A

    2014-04-01

    As global pesticide use increases, the ability to rapidly respond to pesticides by increasing tolerance has important implications for the persistence of nontarget organisms. A recent study of larval amphibians discovered that increased tolerance can be induced by an early exposure to low concentrations of a pesticide. Since natural systems are often exposed to a variety of pesticides that vary in mode of action, we need to know whether the induction of increased tolerance to one pesticide confers increased tolerance to other pesticides. Using larval wood frogs (Lithobates sylvaticus), we investigated whether induction of increased tolerance to the insecticide carbaryl (AChE-inhibitor) can induce increased tolerance to other insecticides that have the same mode of action (chlorpyrifos, malathion) or a different mode of action (Na(+)channel-interfering insecticides; permethrin, cypermethrin). We found that embryonic exposure to sublethal concentrations of carbaryl induced higher tolerance to carbaryl and increased cross-tolerance to malathion and cypermethrin but not to chlorpyrifos or permethrin. In one case, the embryonic exposure to carbaryl induced tolerance in a nonlinear pattern (hormesis). These results demonstrate that that the newly discovered phenomenon of induced tolerance also provides induced cross-tolerance that is not restricted to pesticides with the same mode of action.

  19. Resistance to insecticides in Heliothine Lepidoptera: a global view

    PubMed Central

    McCaffery, A. R.

    1998-01-01

    The status of resistance to organophosphate, carbamate, cyclodiene and pyrethroid insecticides in the heliothine Lepidoptera is reviewed. In particular, resistance in the tobacco budworm, Heliothis virescens, and the corn earworm, Helicoverpa zea, from the New World, and the cotton bollworm, Helicoverpa armigera, from the Old World, are considered in detail. Particular emphasis has been placed on resistance to the most widely used of these insecticide groups, the pyrethroids. In each case, the incidence and current status of resistance are considered before a detailed view of the mechanisms of resistance is given. Controversial issues regarding the nature of mechanisms of resistance to pyrethroid insecticides are discussed. The implications for resistance management are considered.

  20. A comprehensive interpretation of the NEEM basal ice build-up using a multi parametric approach

    NASA Astrophysics Data System (ADS)

    Goossens, T.; Sapart, C. J.; Dahl-Jensen, D.; Popp, T.; El Amri, S.; Tison, J. L.

    2015-10-01

    Basal ice is a common expression to describe debris-laden ice layers found close to the ice-bedrock interface under glaciers and ice sheets. The study of basal ice properties provides a unique opportunity to improve our understanding of subglacial environments and processes and to refine ice sheet behaviour modelling. Here, we present and discuss the results of water stable isotopes (δ18O and δD), ice fabrics, debris weight and gas content of the basal part of the NEEM (North Greenland Eemian Ice Drilling Project) ice core. Below a depth of 2533.85 m, almost 10 m of basal debris-rich material were retrieved from the borehole. The sequence is composed of an alternation of three visually contrasting types of ice: clear ice with specks of particulate inclusions, stratified debris-rich layers, and ice containing dispersed debris. The use of water stable isotope signatures (δ18O and δD) together with other parameters, allows to discriminate between the different types of ice and to unravel the processes involved in their formation and transformation. The basal debris-rich material presents δ18O values [-39.9 ‰; -34.4 ‰] within the range of the above last 300 m of unaltered meteoric ice [-44.9 ‰; -30.6 ‰] spanning a glacial-interglacial range of values. This rules out the hypothesis of a basal ice layer originating from pre-ice sheet ice overridden by the growing ice sheet (as previously suggested e.g. in the case of the GRIP ice core), since the latter would result in an heavier isotopic signature for ice formed at a much lower altitude. We show that clear basal ice with specks corresponds to altered meteoric glacial ice where a climatic signal is preserved. On the other hand, both stratified debris-rich layers and ice containing dispersed debris layers express an "open" or "closed" system melting/refreezing signature, somewhat blurred by mixing processes. Climatic reconstruction is therefore prohibited from these ice types. We propose a first

  1. Risk assessment of the exposure of insecticide operators to fenvalerate during treatment in apple orchards.

    PubMed

    Moon, Joon-Kwan; Park, Sewon; Kim, Eunhye; Lee, Hyeri; Kim, Jeong-Han

    2013-01-16

    Dermal and inhalation exposure of the applicator to the insecticide fenavalerate in an apple orchard was measured for risk assessment during treatment. Emulsifiable concentrate (EC) and wettable powder (WP) formulations were sprayed using a speed sprayer (SS) or power sprayer (PS). Dermal patches, gloves, socks, and masks were used to monitor potential dermal exposure to fenavalerate, while personal air samplers with XAD-2 resins were used to monitor potential inhalation exposure. Validation of analytical methods was performed for the instruments' limit of detection, limit of quantitation, reproducibility, linearity of calibration curve, and recovery of fenvelerate from various exposure matrices. The results were encouraging and reasonable for an exposure study. Applicability of XAD-2 resin was evaluated with a trapping efficiency and breakthrough test. During mixing/loading, the amount of dermal exposure ranged from 262.8 μg (EC/SS) to 1652.6 μg (WP/PS) of fenvalerate, corresponding to ~0.0011-0.0066% of the total prepared quantity. In the case of WP, the amount of dermal exposure was 2032.3 μg (0.0081% of the total applied amount) for SS and 1087.9 μg (0.0145%) for PS after application. In the case of EC, the amount of dermal exposure was 3804.6 μg (0.0152%) for SS and 4055.0 μg (0.0541%) for PS after application. The primary body parts subject to exposure were thigh and upper arm for SS, and thigh and hand for PS. The amount of inhalation exposure with WP was 2.2 μg (8.65 × 10⁻⁶% of the total applied amount) for SS and 1.3 g (1.67 × 10⁻⁵%) for PS. The amount of inhalation exposure with EC was 2.5 μg (9.81 × 10⁻⁶%) for SS and 3.7 μg (4.97 × 10⁻⁵%) for PS. The absorbable quantity of exposure and margin of safety (MOS) were calculated for risk assessment. The MOS for all 4 cases was much greater than 1, indicating a low possibility of risk.

  2. Present status of biochemical research on the insecticide resistance problem*

    PubMed Central

    Agosin, Moises

    1963-01-01

    In order to provide a rational basis for the development of new insecticides, a thorough understanding of resistance mechanisms is necessary and this presupposes a detailed knowledge of the normal biochemical pathways in insects. The author reviews recent progress in this field, particularly the work on enzymatic detoxication of insecticides which appears to be the most important single factor in the production of resistance. The mechanisms include dehydrochlorination and α-methylenic oxidation (DDT), hydrolysis by phosphatases or carboxyesterases (organophosphorus compounds), and oxidation by microsomal enzyme systems (various classes of insecticides). Much work still needs to be done on the enzyme systems involved, especially in relation to substrate specificity and the effect of enzyme inhibitors that might act as synergists of insecticides. PMID:20604178

  3. Insect P450 inhibitors and insecticides: challenges and opportunities.

    PubMed

    Feyereisen, René

    2015-06-01

    P450 enzymes are encoded by a large number of genes in insects, often over a hundred. They play important roles in insecticide metabolism and resistance, and growing numbers of P450 enzymes are now known to catalyse important physiological reactions, such as hormone metabolism or cuticular hydrocarbon synthesis. Ways to inhibit P450 enzymes specifically or less specifically are well understood, as P450 inhibitors are found as drugs, as fungicides, as plant growth regulators and as insecticide synergists. Yet there are no P450 inhibitors as insecticides on the market. As new modes of action are constantly needed to support insecticide resistance management, P450 inhibitors should be considered because of their high potential for insect selectivity, their well-known mechanisms of action and the increasing ease of rational design and testing.

  4. Accidental organophosphate insecticide intoxication in children: a reminder

    PubMed Central

    2011-01-01

    Misuse of organophosphate insecticides, even in case of domestic application, can be life threatening. We report the case of siblings admitted with respiratory distress, pinpoint pupils and slurred speech. The symptoms appear after spraying the skin by insecticides. Plasma pseudocholinesterase level appeared to be very low, consistent with acute intoxication with organophosphate insecticide. Management of organophosphate poisoning consists of airway management, administration of oxygen and fluid, as well as atropine in increasing doses and pralidoxime. Decontamination of the patient's skin and the removal of the patient's clothes are mandatory in order to avoid recontamination of the patient as well as the surrounding healthcare personnel. Plasma pseudocholinesterase analysis is a cheap and an easy indicator for organophosphate insecticides intoxications and could be used for diagnosis and treatment monitoring. PMID:21676238

  5. USING ARRAY TECHNOLOGY TO IDENTIFY POTENTIAL BIOMARKERS FOR PYRETHROID INSECTICIDES.

    EPA Science Inventory

    Pyrethroid insecticides affect nervous system function by disruption of sodium channels in nerve membranes. FQPA requirements for assessing cumulative risk have increased the need for rapid and sensitive biomarkers of effect. This project aims to develop biochemical markers of n...

  6. Recent changes in North West Greenland climate documented by NEEM shallow ice core data and simulations, and implications for past temperature reconstructions

    NASA Astrophysics Data System (ADS)

    Masson-Delmotte, V.; Steen-Larsen, H. C.

    2014-12-01

    Stack records of accumulation, d18O and deuterium excess were produced from up to 4 shallow ice cores at NEEM (North-West Greenland), spanning 1724-2007 and updated to 2011 using pit water stable isotope data. Signal-to-noise ratio is high for d18O (1.3) and accumulation (1.2) but is low for deuterium excess (0.4). No long-term trend is observed in the accumulation record. By contrast, NEEM d18O shows multi-decadal increasing trends in the late 19th century and since the 1980s. Decadal d18O and accumulation variability is in phase with Atlantic Multi-decadal Oscillation indices, and enhanced at the beginning of the 19th century. Large-scale spatial coherency is detected between NEEM and other Greenland ice core and temperature records, strongest for North-West Greenland d18O and summer South-West coastal temperature instrumental records. The strength of correlations with the North Atlantic Oscillation is smaller than in central or south Greenland. The strongest positive d18O values are recorded at NEEM in 2010, followed by 1928, while maximum accumulation occurs in 1933. The coldest/driest decades are depicted at NEEM in 1815-1825 and 1836-1836. The spatial structure of these warm/ wet years and cold/dry decades is investigated using all available Greenland ice cores. During the period 1958-2011, the NEEM accumulation and d18O records are highly correlated with simulated precipitation, temperature and d18O from simulations performed with MAR, LMDZiso and ECHAM5iso atmospheric models, nudged to atmospheric reanalyses. Model-data agreement is better using ERA reanalyses than NCEP/NCAR and 20CR ones. Model performance is poor for deuterium excess. Gridded temperature reconstructions, instrumental data and model outputs at NEEM are used to estimate the d18O-temperature relationship for the strong warming period in 1979-2007. The estimated slope of this relationship is 1.1±0.2‰ per °C, about twice larger than previously used to estimate last interglacial temperature

  7. Mechanism of Insect Resistance to the Microbial Insecticide Bacillus thuringiensis

    NASA Astrophysics Data System (ADS)

    van Rie, J.; McGaughey, W. H.; Johnson, D. E.; Barnett, B. D.; van Mellaert, H.

    1990-01-01

    Receptor binding studies show that resistance of a laboratory-selected Plodia interpunctella strain to a Bacillus thuringiensis insecticidal crystal protein (ICP) is correlated with a 50-fold reduction in affinity of the membrane receptor for this protein. The strain is sensitive to a second type of ICP that apparently recognizes a different receptor. Understanding the mechanism of resistance will provide strategies to prevent or delay resistance and hence prolong the usefulness of B. thuringiensis ICPs as environmentally safe insecticides.

  8. Comparative toxicities of organophosphate and pyrethroid insecticides to aquatic macroarthropods.

    PubMed

    Halstead, Neal T; Civitello, David J; Rohr, Jason R

    2015-09-01

    As agricultural expansion and intensification increase to meet the growing global food demand, so too will insecticide use and thus the risk of non-target effects. Insecticide pollution poses a particular threat to aquatic macroarthropods, which play important functional roles in freshwater ecosystems. Thus, understanding the relative toxicities of insecticides to non-target functional groups is critical for predicting effects on ecosystem functions. We exposed two common macroarthropod predators, the crayfish Procambarus alleni and the water bug Belostoma flumineum, to three insecticides in each of two insecticide classes (three organophosphates: chlorpyrifos, malathion, and terbufos; and three pyrethroids: esfenvalerate, λ-cyhalothrin, and permethrin) to assess their toxicities. We generated 150 simulated environmental exposures using the US EPA Surface Water Contamination Calculator to determine the proportion of estimated peak environmental concentrations (EECs) that exceeded the US EPA level of concern (0.5×LC50) for non-endangered aquatic invertebrates. Organophosphate insecticides generated consistently low-risk exposure scenarios (EECs<0.5×LC50) for both P. alleni and B. flumineum. Pyrethroid exposure scenarios presented consistently high risk (EECs>0.5×LC50) to P. alleni, but not to B. flumineum, where only λ-cyhalothrin produced consistently high-risk exposures. Survival analyses demonstrated that insecticide class accounted for 55.7% and 91.1% of explained variance in P. alleni and B. flumineum survival, respectively. Thus, risk to non-target organisms is well predicted by pesticide class. Identifying insecticides that pose low risk to aquatic macroarthropods might help meet increased demands for food while mitigating against potential negative effects on ecosystem functions.

  9. Comparative toxicities of organophosphate and pyrethroid insecticides to aquatic macroarthropods.

    PubMed

    Halstead, Neal T; Civitello, David J; Rohr, Jason R

    2015-09-01

    As agricultural expansion and intensification increase to meet the growing global food demand, so too will insecticide use and thus the risk of non-target effects. Insecticide pollution poses a particular threat to aquatic macroarthropods, which play important functional roles in freshwater ecosystems. Thus, understanding the relative toxicities of insecticides to non-target functional groups is critical for predicting effects on ecosystem functions. We exposed two common macroarthropod predators, the crayfish Procambarus alleni and the water bug Belostoma flumineum, to three insecticides in each of two insecticide classes (three organophosphates: chlorpyrifos, malathion, and terbufos; and three pyrethroids: esfenvalerate, λ-cyhalothrin, and permethrin) to assess their toxicities. We generated 150 simulated environmental exposures using the US EPA Surface Water Contamination Calculator to determine the proportion of estimated peak environmental concentrations (EECs) that exceeded the US EPA level of concern (0.5×LC50) for non-endangered aquatic invertebrates. Organophosphate insecticides generated consistently low-risk exposure scenarios (EECs<0.5×LC50) for both P. alleni and B. flumineum. Pyrethroid exposure scenarios presented consistently high risk (EECs>0.5×LC50) to P. alleni, but not to B. flumineum, where only λ-cyhalothrin produced consistently high-risk exposures. Survival analyses demonstrated that insecticide class accounted for 55.7% and 91.1% of explained variance in P. alleni and B. flumineum survival, respectively. Thus, risk to non-target organisms is well predicted by pesticide class. Identifying insecticides that pose low risk to aquatic macroarthropods might help meet increased demands for food while mitigating against potential negative effects on ecosystem functions. PMID:25966044

  10. Canadian Arctic sea ice reconstructed from bromine in the Greenland NEEM ice core.

    PubMed

    Spolaor, Andrea; Vallelonga, Paul; Turetta, Clara; Maffezzoli, Niccolò; Cozzi, Giulio; Gabrieli, Jacopo; Barbante, Carlo; Goto-Azuma, Kumiko; Saiz-Lopez, Alfonso; Cuevas, Carlos A; Dahl-Jensen, Dorthe

    2016-09-21

    Reconstructing the past variability of Arctic sea ice provides an essential context for recent multi-year sea ice decline, although few quantitative reconstructions cover the Holocene period prior to the earliest historical records 1,200 years ago. Photochemical recycling of bromine is observed over first-year, or seasonal, sea ice in so-called "bromine explosions" and we employ a 1-D chemistry transport model to quantify processes of bromine enrichment over first-year sea ice and depositional transport over multi-year sea ice and land ice. We report bromine enrichment in the Northwest Greenland Eemian NEEM ice core since the end of the Eemian interglacial 120,000 years ago, finding the maximum extension of first-year sea ice occurred approximately 9,000 years ago during the Holocene climate optimum, when Greenland temperatures were 2 to 3 °C above present values. First-year sea ice extent was lowest during the glacial stadials suggesting complete coverage of the Arctic Ocean by multi-year sea ice. These findings demonstrate a clear relationship between temperature and first-year sea ice extent in the Arctic and suggest multi-year sea ice will continue to decline as polar amplification drives Arctic temperatures beyond the 2 °C global average warming target of the recent COP21 Paris climate agreement.

  11. 10Be climate fingerprints during the Eemian in the NEEM ice core, Greenland

    NASA Astrophysics Data System (ADS)

    Sturevik-Storm, Anna; Aldahan, Ala; Possnert, Göran; Berggren, Ann-Marie; Muscheler, Raimund; Dahl-Jensen, Dorthe; Vinther, Bo M.; Usoskin, Ilya

    2014-09-01

    Several deep Greenland ice cores have been retrieved, however, capturing the Eemian period has been problematic due to stratigraphic disturbances in the ice. The new Greenland deep ice core from the NEEM site (77.45°N, 51.06°W, 2450 m.a.s.l) recovered a relatively complete Eemian record. Here we discuss the cosmogenic 10Be isotope record from this core. The results show Eemian average 10Be concentrations about 0.7 times lower than in the Holocene which suggests a warmer climate and approximately 65-90% higher precipitation in Northern Greenland compared to today. Effects of shorter solar variations on 10Be concentration are smoothed out due to coarse time resolution, but occurrence of a solar maximum at 115.26-115.36 kyr BP is proposed. Relatively high 10Be concentrations are found in the basal ice sections of the core which may originate from the glacial-interglacial transition and relate to a geomagnetic excursion about 200 kyr BP.

  12. Canadian Arctic sea ice reconstructed from bromine in the Greenland NEEM ice core

    PubMed Central

    Spolaor, Andrea; Vallelonga, Paul; Turetta, Clara; Maffezzoli, Niccolò; Cozzi, Giulio; Gabrieli, Jacopo; Barbante, Carlo; Goto-Azuma, Kumiko; Saiz-Lopez, Alfonso; Cuevas, Carlos A.; Dahl-Jensen, Dorthe

    2016-01-01

    Reconstructing the past variability of Arctic sea ice provides an essential context for recent multi-year sea ice decline, although few quantitative reconstructions cover the Holocene period prior to the earliest historical records 1,200 years ago. Photochemical recycling of bromine is observed over first-year, or seasonal, sea ice in so-called “bromine explosions” and we employ a 1-D chemistry transport model to quantify processes of bromine enrichment over first-year sea ice and depositional transport over multi-year sea ice and land ice. We report bromine enrichment in the Northwest Greenland Eemian NEEM ice core since the end of the Eemian interglacial 120,000 years ago, finding the maximum extension of first-year sea ice occurred approximately 9,000 years ago during the Holocene climate optimum, when Greenland temperatures were 2 to 3 °C above present values. First-year sea ice extent was lowest during the glacial stadials suggesting complete coverage of the Arctic Ocean by multi-year sea ice. These findings demonstrate a clear relationship between temperature and first-year sea ice extent in the Arctic and suggest multi-year sea ice will continue to decline as polar amplification drives Arctic temperatures beyond the 2 °C global average warming target of the recent COP21 Paris climate agreement. PMID:27650478

  13. Canadian Arctic sea ice reconstructed from bromine in the Greenland NEEM ice core

    NASA Astrophysics Data System (ADS)

    Spolaor, Andrea; Vallelonga, Paul; Turetta, Clara; Maffezzoli, Niccolò; Cozzi, Giulio; Gabrieli, Jacopo; Barbante, Carlo; Goto-Azuma, Kumiko; Saiz-Lopez, Alfonso; Cuevas, Carlos A.; Dahl-Jensen, Dorthe

    2016-09-01

    Reconstructing the past variability of Arctic sea ice provides an essential context for recent multi-year sea ice decline, although few quantitative reconstructions cover the Holocene period prior to the earliest historical records 1,200 years ago. Photochemical recycling of bromine is observed over first-year, or seasonal, sea ice in so-called “bromine explosions” and we employ a 1-D chemistry transport model to quantify processes of bromine enrichment over first-year sea ice and depositional transport over multi-year sea ice and land ice. We report bromine enrichment in the Northwest Greenland Eemian NEEM ice core since the end of the Eemian interglacial 120,000 years ago, finding the maximum extension of first-year sea ice occurred approximately 9,000 years ago during the Holocene climate optimum, when Greenland temperatures were 2 to 3 °C above present values. First-year sea ice extent was lowest during the glacial stadials suggesting complete coverage of the Arctic Ocean by multi-year sea ice. These findings demonstrate a clear relationship between temperature and first-year sea ice extent in the Arctic and suggest multi-year sea ice will continue to decline as polar amplification drives Arctic temperatures beyond the 2 °C global average warming target of the recent COP21 Paris climate agreement.

  14. Antimicrobial activity of a neem cake extract in a broth model meat system.

    PubMed

    Del Serrone, Paola; Nicoletti, Marcello

    2013-08-02

    This work reports on the antimicrobial activity of an ethyl acetate extract of neem (Azadirachta indica) cake (NCE) against bacteria affecting the quality of retail fresh meat in a broth model meat system. NCE (100 µg) was also tested by the agar disc diffusion method. It inhibited the growth of all tested microorganisms. The NCE growth inhibition zone (IZ) ranged 11.33-22.67 mm while the ciprofloxacin (10 µg) IZ ranged from 23.41-32.67 mm. There was no significant difference (p ≤ 0.05) between the antimicrobial activity of NCE and ciprofloxacin vs. C. jejuni and Leuconostoc spp. The NCE antibacterial activity was moreover determined at lower concentrations (1:10-1:100,000) in micro-assays. The percent growth reduction ranged from 61 ± 2.08-92 ± 3.21. The higher bacterial growth reduction was obtained at 10 µg concentration of NCE. Species-specific PCR and multiplex PCR with the DNA dye propidium monoazide were used to directly detect viable bacterial cells from experimentally contaminated meat samples. The numbers of bacterial cells never significantly (p ≤ 0.05) exceeded the inocula concentration used to experimentally contaminate the NCE treated meat. This report represents a screening methodology to evaluate the antimicrobial capability of a herbal extract to preserve meat.

  15. Neem (Azadirachta indica A. Juss) Oil to Tackle Enteropathogenic Escherichia coli

    PubMed Central

    Del Serrone, Paola; Nicoletti, Marcello

    2015-01-01

    Neem (Azadirachta indica A. Juss) oil (NO) was assayed against forty-eight isolates of Escherichia coli by standardised disc diffusion test and microdilution test. By molecular biology characterization, fourteen isolates resulted in diarrheagenic E. coli with sixteen primer pairs that specifically amplify unique sequences of virulence genes and of 16S rRNA. The NO showed biological activity against all isolates. The bacterial growth inhibition zone by disc diffusion method (100 µL NO) ranged between 9.50 ± 0.70 and 30.00 ± 1.00 mm. The antibacterial activity was furthermore determined at lower NO concentrations (1 : 10–1 : 10,000). The percent of growth reduction ranged between 23.71 ± 1.00 and 99.70 ± 1.53. The highest bacterial growth reduction was 1 : 10 NO concentration with 50 µL of bacterial suspension (ca. 1 × 106 CFU/mL). There is significant difference between the antibacterial activities against pathogenic and nonpathogenic E. coli, as well as NO and ciprofloxacin activities. Viable cells after the different NO concentration treatments were checked by molecular biology assay using PMA dye. On the basis of the obtained results, NO counteracts E. coli and also influences the virulence of E. coli viable cells after NO treatment. The NO metabolomic composition was obtained using fingerprint HPTLC. PMID:26064900

  16. Antimicrobial Activity of a Neem Cake Extract in a Broth Model Meat System

    PubMed Central

    Del Serrone, Paola; Nicoletti, Marcello

    2013-01-01

    This work reports on the antimicrobial activity of an ethyl acetate extract of neem (Azadirachta indica) cake (NCE) against bacteria affecting the quality of retail fresh meat in a broth model meat system. NCE (100 µg) was also tested by the agar disc diffusion method. It inhibited the growth of all tested microorganisms. The NCE growth inhibition zone (IZ) ranged 11.33–22.67 mm while the ciprofloxacin (10 µg) IZ ranged from 23.41–32.67 mm. There was no significant difference (p ≤ 0.05) between the antimicrobial activity of NCE and ciprofloxacin vs. C. jejuni and Leuconostoc spp. The NCE antibacterial activity was moreover determined at lower concentrations (1:10–1:100,000) in micro-assays. The percent growth reduction ranged from 61 ± 2.08–92 ± 3.21. The higher bacterial growth reduction was obtained at 10 µg concentration of NCE. Species-specific PCR and multiplex PCR with the DNA dye propidium monoazide were used to directly detect viable bacterial cells from experimentally contaminated meat samples. The numbers of bacterial cells never significantly (p ≤ 0.05) exceeded the inocula concentration used to experimentally contaminate the NCE treated meat. This report represents a screening methodology to evaluate the antimicrobial capability of a herbal extract to preserve meat. PMID:23917814

  17. 10Be climate fingerprints during the Eemian in the NEEM ice core, Greenland

    PubMed Central

    Sturevik-Storm, Anna; Aldahan, Ala; Possnert, Göran; Berggren, Ann-Marie; Muscheler, Raimund; Dahl-Jensen, Dorthe; Vinther, Bo M.; Usoskin, Ilya

    2014-01-01

    Several deep Greenland ice cores have been retrieved, however, capturing the Eemian period has been problematic due to stratigraphic disturbances in the ice. The new Greenland deep ice core from the NEEM site (77.45°N, 51.06°W, 2450 m.a.s.l) recovered a relatively complete Eemian record. Here we discuss the cosmogenic 10Be isotope record from this core. The results show Eemian average 10Be concentrations about 0.7 times lower than in the Holocene which suggests a warmer climate and approximately 65–90% higher precipitation in Northern Greenland compared to today. Effects of shorter solar variations on 10Be concentration are smoothed out due to coarse time resolution, but occurrence of a solar maximum at 115.26–115.36 kyr BP is proposed. Relatively high 10Be concentrations are found in the basal ice sections of the core which may originate from the glacial-interglacial transition and relate to a geomagnetic excursion about 200 kyr BP. PMID:25266953

  18. Neem (Azadirachta indica A. Juss) Oil to Tackle Enteropathogenic Escherichia coli.

    PubMed

    Del Serrone, Paola; Toniolo, Chiara; Nicoletti, Marcello

    2015-01-01

    Neem (Azadirachta indica A. Juss) oil (NO) was assayed against forty-eight isolates of Escherichia coli by standardised disc diffusion test and microdilution test. By molecular biology characterization, fourteen isolates resulted in diarrheagenic E. coli with sixteen primer pairs that specifically amplify unique sequences of virulence genes and of 16S rRNA. The NO showed biological activity against all isolates. The bacterial growth inhibition zone by disc diffusion method (100 µL NO) ranged between 9.50 ± 0.70 and 30.00 ± 1.00 mm. The antibacterial activity was furthermore determined at lower NO concentrations (1 : 10-1 : 10,000). The percent of growth reduction ranged between 23.71 ± 1.00 and 99.70 ± 1.53. The highest bacterial growth reduction was 1 : 10 NO concentration with 50 µL of bacterial suspension (ca. 1 × 10(6) CFU/mL). There is significant difference between the antibacterial activities against pathogenic and nonpathogenic E. coli, as well as NO and ciprofloxacin activities. Viable cells after the different NO concentration treatments were checked by molecular biology assay using PMA dye. On the basis of the obtained results, NO counteracts E. coli and also influences the virulence of E. coli viable cells after NO treatment. The NO metabolomic composition was obtained using fingerprint HPTLC. PMID:26064900

  19. Canadian Arctic sea ice reconstructed from bromine in the Greenland NEEM ice core.

    PubMed

    Spolaor, Andrea; Vallelonga, Paul; Turetta, Clara; Maffezzoli, Niccolò; Cozzi, Giulio; Gabrieli, Jacopo; Barbante, Carlo; Goto-Azuma, Kumiko; Saiz-Lopez, Alfonso; Cuevas, Carlos A; Dahl-Jensen, Dorthe

    2016-01-01

    Reconstructing the past variability of Arctic sea ice provides an essential context for recent multi-year sea ice decline, although few quantitative reconstructions cover the Holocene period prior to the earliest historical records 1,200 years ago. Photochemical recycling of bromine is observed over first-year, or seasonal, sea ice in so-called "bromine explosions" and we employ a 1-D chemistry transport model to quantify processes of bromine enrichment over first-year sea ice and depositional transport over multi-year sea ice and land ice. We report bromine enrichment in the Northwest Greenland Eemian NEEM ice core since the end of the Eemian interglacial 120,000 years ago, finding the maximum extension of first-year sea ice occurred approximately 9,000 years ago during the Holocene climate optimum, when Greenland temperatures were 2 to 3 °C above present values. First-year sea ice extent was lowest during the glacial stadials suggesting complete coverage of the Arctic Ocean by multi-year sea ice. These findings demonstrate a clear relationship between temperature and first-year sea ice extent in the Arctic and suggest multi-year sea ice will continue to decline as polar amplification drives Arctic temperatures beyond the 2 °C global average warming target of the recent COP21 Paris climate agreement. PMID:27650478

  20. Comparative toxicity of two azadirachtin-based neem pesticides to Daphnia pulex.

    PubMed

    Goktepe, Ipek; Plhak, Leslie C

    2002-01-01

    Azadirachtin (AZA)-based pesticides (Neemix and Bioneem) demonstrated toxicity in 48-h nonrenewal toxicity assays using Daphnia pulex at levels that were comparable with several organophosphate pesticides. The median lethal concentration (LC50) values for the two neem pesticides were found to be 0.028 and 0.033 microl/ml, respectively. The LC50 value for nonformulated (95% pure) AZA was determined to be 0.382 microg AZA/ml. Neemix and Bioneem were exposed to air and northern sky daylight in a light box at 24 and 37 degrees C for 1, 3, 6, and 9 d. Standard 48-h acute toxicity tests were used to determine the effect of aging in these dry environmental conditions. Neemix and Bioneem were also fractionated into volatile and nonvolatile fractions, and the toxicity of each was tested. Compared with Neemix, Bioneem remained toxic longer when exposed to light and air at 37 degrees C, indicating that this pesticide may be less prone to environmental degradation. When fractionated, the nonvolatile fractions for both pesticides exhibited significantly lower LC50 values than the full formulations. These results suggest that, depending on the application rate and environmental fate, AZA-based pesticides may have direct adverse effects on aquatic organisms and that the toxicity and stability of formulated pesticides depend on factors other than only the AZA concentration. PMID:11804058

  1. Extreme 13C depletion of CCl2F2 in firn air samples from NEEM, Greenland

    NASA Astrophysics Data System (ADS)

    Zuiderweg, A.; Holzinger, R.; Martinerie, P.; Schneider, R.; Kaiser, J.; Witrant, E.; Etheridge, D.; Rubino, M.; Petrenko, V.; Blunier, T.; Röckmann, T.

    2012-07-01

    A series of 12 high volume air samples collected from the S2 firn core during the North Greenland Eemian Ice Drilling (NEEM) 2009 campaign have been measured for mixing ratio and stable carbon isotope composition of the chlorofluorocarbon CFC-12 (CCl2F2). While the mixing ratio measurements compare favorably to other firn air studies, the isotope results show extreme 13C depletion at the deepest measurable depth (65 m), to values lower than δ13C = -80‰ vs. VPDB (the international stable carbon isotope scale), compared to present day surface tropospheric measurements near -40‰. Firn air modeling was used to interpret these measurements. Reconstructed atmospheric time series indicate even larger depletions (to -120‰) near 1950 AD, with subsequent rapid enrichment of the atmospheric reservoir of the compound to the present day value. Mass-balance calculations show that this change must have been caused by a large change in the isotopic composition of anthropogenic CFC-12 emissions, probably due to technological changes in the CFC production process over the last 80 yr. Propagating the mass-balance calculations into the future demonstrates that as emissions decrease to zero, isotopic fractionation by the stratospheric sinks will lead to continued 13C enrichment in atmospheric CFC-12.

  2. Extreme 13C depletion of CCl2F2 in firn air samples from NEEM, Greenland

    NASA Astrophysics Data System (ADS)

    Zuiderweg, A.; Holzinger, R.; Martinerie, P.; Schneider, R.; Kaiser, J.; Witrant, E.; Etheridge, D.; Petrenko, V.; Blunier, T.; Röckmann, T.

    2013-01-01

    A series of 12 high volume air samples collected from the S2 firn core during the North Greenland Eemian Ice Drilling (NEEM) 2009 campaign have been measured for mixing ratio and stable carbon isotope composition of the chlorofluorocarbon CFC-12 (CCl2F2). While the mixing ratio measurements compare favorably to other firn air studies, the isotope results show extreme 13C depletion at the deepest measurable depth (65 m), to values lower than δ13C = -80‰ vs. VPDB (the international stable carbon isotope scale), compared to present day surface tropospheric measurements near -40‰. Firn air modeling was used to interpret these measurements. Reconstructed atmospheric time series indicate even larger depletions (to -120‰) near 1950 AD, with subsequent rapid enrichment of the atmospheric reservoir of the compound to the present day value. Mass-balance calculations show that this change is likely to have been caused by a large change in the isotopic composition of anthropogenic CFC-12 emissions, probably due to technological advances in the CFC production process over the last 80 yr, though direct evidence is lacking.

  3. Neem (Azadirachta indica) kernel meal in the diet of White Leghorn layers.

    PubMed

    Gowda, S K; Verma, S V; Elangovan, A V; Singh, S D

    1998-12-01

    1. Neem kernel meal (NKM) was incorporated into a standard layer diet at 0, 100, 150 and 200 g/kg, replacing parts of the soyabean meal and deoiled rice bran. Each diet was offered to 18 White Leghorn layers (25 weeks, 50% egg production) in individual cages for a period of 12 weeks. 2. Results indicated significantly lower food intakes (P < 0.01), rates of egg production and egg weights in birds fed on the diets with NKM at 150 and 200 g/kg. Fertility and hatchability were also adversely affected by the higher inclusion rates of NKM. 3. Except for lower egg shell weight and shell thickness (P < 0.05) in hens fed NKM at 150 and 200 g/kg, the internal egg quality characteristics were comparable in all groups. 4. Feeding NKM beyond 100 g/kg to laying hens significantly (P < 0.01) reduced the content of haemoglobin, erythrocyte count, packed cell volume, serum calcium and uric acid concentrations. However, the leucocyte count, plasma glucose concentration and serum glutamate oxaloacetate transaminase activity were unaltered. Serum glutamate pyruvate transaminase activity was significantly (P < 0.05) reduced in birds fed NKM at 200 g/kg. 5. Thus NKM at 100 g/kg in a layer diet would appear to be safe and cost-effective. PMID:9925318

  4. Protective role of extracts of neem seeds in diabetes caused by streptozotocin in rats.

    PubMed

    Gupta, S; Kataria, M; Gupta, P K; Murganandan, S; Yashroy, R C

    2004-02-01

    Effect of petroleum ether extracts of kernel (NSK) and husk (NSH) of neem (Azadirachta indica A. Juss, Meliaceae) seeds on the prevention of oxidative stress caused by streptozotocin (STZ) was investigated. Diabetes mellitus was induced in adult male Wistar rats after administration of STZ (55 mg/kg b.wt., i.p., tail vein). The effect of NSK (2 gm/kg, b.wt.) and NSH (0.9 gm/kg, b.wt.) orally for 28 days was investigated in diabetic rats. Insulin-treated diabetic rats (6 U/kg, i.p., 28 days.) served as positive control. Diabetic rats given normal saline served as diabetic control. Rats that neither received STZ nor drugs served as normal control. Serum creatine phosphokinase (CPK) increased in diabetic rats was significantly decreased on insulin, NSK, and NSH treatments. The decrease in activities of superoxide dismutase (SOD) and catalase (CAT) and increase in lipid peroxidation (LPO) of erythrocytes as observed in diabetes was regained after insulin, NSH, and NSK treatments. However, there was insignificant improvement in SOD, CAT, and LPO of kidney on NSK and NSH treatment. In spite of increased CAT and SOD activities in liver and heart, LPO was also increased in diabetic rats. Insulin, NSH, and NSK treatments significantly protected animals from cardiac damage but not hepatic. Results suggest that NSH and NSK prevent oxidative stress caused by STZ in heart and erythrocytes. However, no such preventive effect was observed on renal and hepatic toxicity. PMID:15013179

  5. The effect of subacute administration of a neem pesticide on rat metabolic enzymes.

    PubMed

    Mahboob, M; Siddiqui, M K; Jamil, K

    1998-07-01

    Acute toxicity of a neem pesticide (Vepacide-Tech) was studied in male Wistar rats by oral (single) intubation for 7 days. Vepacide was found to be moderately toxic to rat based on LD50 value. Subacute toxicity of Vepacide-Tech was also studied in male rats by oral (multiple) intubation of low (80 mg Kg-1 day-1), medium (160 mg Kg-1 day-1) and high dose (320 mg Kg-1 day-1) for 90 days. High dose caused a significant decrease in Cytochrome P-450 (Cyt. P-450) concentration at 45 and 90 days and the medium dose caused same effect at 90th day in liver and lung. Kidney showed similar effect at 90 days by the three doses. Cytochrome b5 (Cyt. b5) concentration was significantly decreased in liver, lung and kidney at 45 and 90 days at medium and high doses. Brain Cyt.b5 concentration was decreased on 90th day at high dose. Cytochrome P-450 reductase (Cyt.P-450 reductase) concentration was decreased significantly in liver and brain at 45 and 90 days, respectively at medium and high doses. The withdrawal study (28 days) has shown significant recovery. These results demonstrate that low levels exposure of Vepacide may have significant effect on the xenobiotic detoxification mechanism of different tissues of rat. PMID:9674151

  6. Neem (Azadirachta indica A. Juss) Oil to Tackle Enteropathogenic Escherichia coli.

    PubMed

    Del Serrone, Paola; Toniolo, Chiara; Nicoletti, Marcello

    2015-01-01

    Neem (Azadirachta indica A. Juss) oil (NO) was assayed against forty-eight isolates of Escherichia coli by standardised disc diffusion test and microdilution test. By molecular biology characterization, fourteen isolates resulted in diarrheagenic E. coli with sixteen primer pairs that specifically amplify unique sequences of virulence genes and of 16S rRNA. The NO showed biological activity against all isolates. The bacterial growth inhibition zone by disc diffusion method (100 µL NO) ranged between 9.50 ± 0.70 and 30.00 ± 1.00 mm. The antibacterial activity was furthermore determined at lower NO concentrations (1 : 10-1 : 10,000). The percent of growth reduction ranged between 23.71 ± 1.00 and 99.70 ± 1.53. The highest bacterial growth reduction was 1 : 10 NO concentration with 50 µL of bacterial suspension (ca. 1 × 10(6) CFU/mL). There is significant difference between the antibacterial activities against pathogenic and nonpathogenic E. coli, as well as NO and ciprofloxacin activities. Viable cells after the different NO concentration treatments were checked by molecular biology assay using PMA dye. On the basis of the obtained results, NO counteracts E. coli and also influences the virulence of E. coli viable cells after NO treatment. The NO metabolomic composition was obtained using fingerprint HPTLC.

  7. Sustainable production of azadirachtin from differentiated in vitro cell lines of neem (Azadirachta indica)

    PubMed Central

    Singh, Mithilesh; Chaturvedi, Rakhi

    2013-01-01

    Azadirachtin has high industrial demand due to its immediate application as an ecofriendly, biodegradable biopesticide and also due to its various other significant bioactivities. To date, the only commercially feasible way to produce azadirachtin is extraction from seeds, but their availability is very limited as the tree flowers only once a year and only one-third of the fruits are collected due to operational problems. Further, due to the strict out-breeding nature of the plant, the seeds are highly heterozygous, resulting in inconsistent metabolite production. Therefore, in the present study, to achieve sustainable production of azadirachtin, dedifferentiated and redifferentiated calli derived from various explants of neem—zygotic embryo, leaf and ovary—were investigated for their potential to biosynthesize azadirachtin. High-performance liquid chromatography analysis of the in vitro cell lines showed the presence of azadirachtin in all the samples tested, the content of which in cultured cells varied with explant source and cell differentiation response. The presence of azadirachtin in samples was further confirmed by positive electrospray ionization mass spectroscopy. The zygotic embryo cultures of neem accumulated much higher amounts of azadirachtin than leaf and ovary cultures. Furthermore, organized in vitro callus cultures (redifferentiated) supported higher azadirachtin biosynthesis, while unorganized callus cultures (dedifferentiated) supported the least. The maximum azadirachtin content of 2.33 mg g−1 dry weight was obtained from redifferentiated immature zygotic embryo cultures.

  8. Extraction of Ice Sheet Layers from Two Intersected Radar Echograms Near Neem Ice Core in Greenland

    NASA Astrophysics Data System (ADS)

    Xiong, S.; Muller, J.-P.

    2016-06-01

    Accumulation of snow and ice over time result in ice sheet layers. These can be remotely sensed where there is a contrast in electromagnetic properties, which reflect variations of the ice density, acidity and fabric orientation. Internal ice layers are assumed to be isochronous, deep beneath the ice surface, and parallel to the direction of ice flow. The distribution of internal layers is related to ice sheet dynamics, such as the basal melt rate, basal elevation variation and changes in ice flow mode, which are important parameters to model the ice sheet. Radar echo sounder is an effective instrument used to study the sedimentology of the Earth and planets. Ice Penetrating Radar (IPR) is specific kind of radar echo sounder, which extends studies of ice sheets from surface to subsurface to deep internal ice sheets depending on the frequency utilised. In this study, we examine a study site where folded ice occurs in the internal ice sheet south of the North Greenland Eemian ice drilling (NEEM) station, where two intersected radar echograms acquired by the Multi-channel Coherent Radar Depth Sounder (MCoRDS) employed in the NASA's Operation IceBridge (OIB) mission imaged this folded ice. We propose a slice processing flow based on a Radon Transform to trace and extract these two sets of curved ice sheet layers, which can then be viewed in 3-D, demonstrating the 3-D structure of the ice folds.

  9. Nanoscale Bio-Molecular Control Using EC-OWLS

    SciTech Connect

    Bearinger, J P; Voros, J; Hubbell, J A; Textor, M

    2002-11-20

    A recently developed technique termed ''Electrochemical Optical Waveguide Lightmode Spectroscopy'' (EC-OWLS) [1] combines evanescent-field optical sensing with electrochemical control of surface adsorption processes. Initial EC-OWLS investigations efficiently monitored molecular surface adsorption and layer thickness changes of an adsorbed polymer layer examined in situ as a function of potential applied to a waveguide1. A layer of indium tin oxide (ITO) served as both a high refractive index waveguide for optical sensing, and a conductive electrode; an electrochemical flow-through fluid cell incorporated working, reference and counter electrodes. Poly(L-lysine)-grafted-poly(ethylene glycol) (PLL-g-PEG) served as a model, polycation adsorbate. Results indicate that adsorption and desorption of PLL-g-PEG from aqueous buffer are a function of applied potential, and that binding events subsequent to PLL-g-PEG functionalization are dependent on reorganization in the molecular adlayer.

  10. Assessing the fate and effects of an insecticidal formulation.

    PubMed

    de Perre, Chloé; Williard, Karl W J; Schoonover, Jon E; Young, Bryan G; Murphy, Tracye M; Lydy, Michael J

    2015-01-01

    A 3-yr study was conducted on a corn field in central Illinois, USA, to understand the fate and effects of an insecticidal formulation containing the active ingredients phostebupirim and cyfluthrin. The objectives were to determine the best tillage practice (conventional vs conservation tillage) in terms of grain yields and potential environmental risk, to assess insecticidal exposure using concentrations measured in soil and runoff water and sediments, to compare measured insecticidal concentrations with predicted concentrations from selected risk assessment exposure models, and to calculate toxicity benchmarks from laboratory bioassays performed on reference aquatic and terrestrial nontarget organisms, using individual active ingredients and the formulation. Corn grain yields were not significantly different based on tillage treatment. Similarly, field concentrations of insecticides were not significantly (p > 0.05) different in strip tillage versus conventional tillage, suggesting that neither of the tillage systems would enable greater environmental risk from the insecticidal formulation. Risk quotients were calculated from field concentrations and toxicity data to determine potential risk to nontarget species. The insecticidal formulation used at the recommended rate resulted in soil, sediment, and water concentrations that were potentially harmful to aquatic and terrestrial invertebrates, if exposure occurred, with risk quotients up to 34. PMID:25331413

  11. Impact of some selected insecticides application on soil microbial respiration.

    PubMed

    Latif, M A; Razzaque, M A; Rahman, M M

    2008-08-15

    The aim of present study was to investigate the impact of selected insecticides used for controlling brinjal shoot and fruit borer on soil microorganisms and to find out the insecticides or nontoxic to soil microorganism the impact of nine selected insecticides on soil microbial respiration was studied in the laboratory. After injection of different insecticides solutions, the soil was incubated in the laboratory at room temperature for 32 days. The amount of CO2 evolved due to soil microbial respiration was determined at 2, 4, 8, 16, 24 and 32 days of incubation. Flubendiamide, nimbicidine, lambda-cyhalothrin, abamectin and thiodicarb had stimulatory effect on microbial respiration during the initial period of incubation. Chlorpyriphos, cartap and carbosulfan had inhibitory effect on microbial respiration and cypermethrin had no remarkable effect during the early stage of incubation. The negative effect of chlorpyriphos, cartap and carbosulfan was temporary, which was disappeared after 4 days of insecticides application. No effect of the selected insecticides on soil microorganisms was observed after 24 or 32 days of incubation. PMID:19266909

  12. Australian funnel-web spiders: master insecticide chemists.

    PubMed

    Tedford, Hugo W; Sollod, Brianna L; Maggio, Francesco; King, Glenn F

    2004-04-01

    Arthropods are the most diverse animal group on the planet. Their ability to inhabit a vast array of ecological niches has inevitably brought them into conflict with humans. Although only a small minority are classified as pest species, they nevertheless destroy about a quarter of the world's annual crop production and transmit an impressive array of pathogens of human and veterinary public health importance. Arthropod pests have been controlled almost exclusively with chemical insecticides since the introduction of DDT in the 1940s. However, the evolution of resistance to many insecticides, coupled with increased awareness of the potential environmental and human and animal health impacts of these chemicals, has stimulated the search for new insecticidal compounds, novel molecular targets, and alternative control methods. Spider venoms are complex chemical cocktails that have evolved to kill or paralyze arthropod prey, and they represent a largely untapped reservoir of insecticidal compounds. This review focuses on several families of invertebrate-specific peptide neurotoxins that were isolated from the venom of Australian funnel-web spiders. These peptides are promising insecticide leads because of their selectivity for invertebrates and activity on previously unvalidated targets. These toxins should facilitate the development of novel target-based screens for new insecticide leads, while their mapped pharmacophores will provide templates for rational design of mimetics that act at these target sites. Furthermore, genes encoding these toxins can be used to improve the efficacy of insect-specific viruses.

  13. Computational Electromagnetic Modeling of SansEC(Trade Mark) Sensors

    NASA Technical Reports Server (NTRS)

    Smith, Laura J.; Dudley, Kenneth L.; Szatkowski, George N.

    2011-01-01

    This paper describes the preliminary effort to apply computational design tools to aid in the development of an electromagnetic SansEC resonant sensor composite materials damage detection system. The computational methods and models employed on this research problem will evolve in complexity over time and will lead to the development of new computational methods and experimental sensor systems that demonstrate the capability to detect, diagnose, and monitor the damage of composite materials and structures on aerospace vehicles.

  14. Summary of the experimental session EC-10 workshop

    SciTech Connect

    Lohr, J.

    1997-06-01

    This review summarizes a subset of the EC-10 presentations which had been assigned by the organizing committee identification tags beginning with EX. There were fourteen presentations in this group, seven oral and seven posters. Included among the oral presentations were two invited talks. With the exception of the review of plans for electron cyclotron waves in ITER, there were all reports of physics experiments or operational experience as opposed to accounts of hardware development.

  15. EC: an efficient error correction algorithm for short reads

    PubMed Central

    2015-01-01

    Background In highly parallel next-generation sequencing (NGS) techniques millions to billions of short reads are produced from a genomic sequence in a single run. Due to the limitation of the NGS technologies, there could be errors in the reads. The error rate of the reads can be reduced with trimming and by correcting the erroneous bases of the reads. It helps to achieve high quality data and the computational complexity of many biological applications will be greatly reduced if the reads are first corrected. We have developed a novel error correction algorithm called EC and compared it with four other state-of-the-art algorithms using both real and simulated sequencing reads. Results We have done extensive and rigorous experiments that reveal that EC is indeed an effective, scalable, and efficient error correction tool. Real reads that we have employed in our performance evaluation are Illumina-generated short reads of various lengths. Six experimental datasets we have utilized are taken from sequence and read archive (SRA) at NCBI. The simulated reads are obtained by picking substrings from random positions of reference genomes. To introduce errors, some of the bases of the simulated reads are changed to other bases with some probabilities. Conclusions Error correction is a vital problem in biology especially for NGS data. In this paper we present a novel algorithm, called Error Corrector (EC), for correcting substitution errors in biological sequencing reads. We plan to investigate the possibility of employing the techniques introduced in this research paper to handle insertion and deletion errors also. Software availability The implementation is freely available for non-commercial purposes. It can be downloaded from: http://engr.uconn.edu/~rajasek/EC.zip. PMID:26678663

  16. The last interglacial climate in EC-Earth - comparing the direct and indirect impacts of the insolation changes

    NASA Astrophysics Data System (ADS)

    Anker Pedersen, Rasmus; Langen, Peter Lang; Vinther, Bo

    2016-04-01

    The last interglacial warm climate state was influenced by substantial changes in the annual insolation cycle. The impact of the insolation changes has been investigated using a time-slice simulation with the EC-Earth earth system model. The model climate was forced with the insolation and atmospheric greenhouse gas concentrations from 125,000 years before present, and the resulting quasi-equilibrium state has been analyzed and compared to a pre-industrial climate state. The simulations indicate an annual mean global warming of approximately 1 K. The tropical region exhibits lower temperatures and stronger monsoonal systems, while the Arctic region shows a warming of about 3 K throughout the year. Arctic sea ice changes appear to be an important driver of warming, especially in relation to a northward shift of the ice edge in the North Atlantic region. Proxy data from ice and ocean sediment cores indicate substantial warming in parts of the North Atlantic region that could be related to similar sea ice changes. The relative importance of the sea ice and sea surface temperature changes and the direct contribution from the insolation is further investigated using a series of experiments in an atmosphere-only version of the model. Based on the results from the coupled model, we assess the relative contributions using hybrid simulations of the atmospheric response to a combination of last interglacial sea surface temperatures and sea ice conditions and pre-industrial insolation, and vice versa. Special attention is given to the simulated response over the Greenland ice sheet and the potential implications for proxy data from ice cores. Both temperature and precipitation changes could impact the ice core records, and the seasonal and spatial changes over Greenland are analyzed in detail. At the NEEM ice core location, a general warming tendency is accompanied by an increase of summer snowfall that contributes to a further increase of the precipitation

  17. Toxicity of the insecticide terbufos, its oxidation metabolites, and the herbicide atrazine in binary mixtures to Ceriodaphnia cf dubia.

    PubMed

    Choung, Catherine B; Hyne, Ross V; Stevens, Mark M; Hose, Grant C

    2011-04-01

    The acute toxicity of terbufos and its major metabolites, tested alone, in binary mixtures or in combination with atrazine were evaluated using neonates of the cladoceran Ceriodaphnia cf dubia. Terbufos, terbufos sulfoxide, and terbufos sulfone tested individually were highly toxic to C. cf dubia, with mean 96-h EC(50) values of 0.08, 0.36, and 0.19 μg/l, respectively. The addition of atrazine (10 μg/l) significantly increased the toxicity of terbufos. The toxicity of terbufos sulfone was unaffected by atrazine, whereas the results for terbufos sulfoxide were equivocal. Equitoxic mixtures of the metabolites showed additive toxicity to C. cf dubia. The high toxicities of terbufos and its environmentally persistent oxidative metabolites suggest that contamination of aquatic systems with this insecticide mixture and the coapplied herbicide atrazine might pose a greater hazard to some biota than their individual toxicities.

  18. Present status of developing petroleum-substituting energy (EC)

    NASA Astrophysics Data System (ADS)

    1993-03-01

    The EC has had approximately 50% of its total energy demand supplied by imports from the exterior of the Community. Hence, it is getting important to develop oil-substituting renewable energy as well as to curtail the emission of carbon dioxide. In consideration of these situations, the results of investigation on the energy policy of the European Community are described. The policy comprises three courses: European Energy Charter, formation of an open European Community energy market, and environmental conservation. Particularly, concerning the reduction of carbon dioxide emission, the EC Council has decided to introduce carbon dioxide taxation so as to suppress the carbon dioxide emission in the year 2000 to the 1990 level. The arrangement for its introduction, however, encountered with difficulties because of the opposition of various countries other than the European Community and the industrial world of the European Community. Legislation of the investment promotion law for energy saving and the construction of infrastructure footing and an information network are ineffective due to the sluggish fuel price and economic recession. A plurality of EC member countries are advancing a comprehensive activity within the framework of the joint programs of research, development, and demonstration set for the renewable energy policy ensuring energy supply and environmental harmonization.

  19. Unprecedented conformational flexibility revealed in the ligand-binding domains of the Bovicola ovis ecdysone receptor (EcR) and ultraspiracle (USP) subunits.

    PubMed

    Ren, Bin; Peat, Thomas S; Streltsov, Victor A; Pollard, Matthew; Fernley, Ross; Grusovin, Julian; Seabrook, Shane; Pilling, Pat; Phan, Tram; Lu, Louis; Lovrecz, George O; Graham, Lloyd D; Hill, Ronald J

    2014-07-01

    The heterodimeric ligand-binding region of the Bovicola ovis ecdysone receptor has been crystallized either in the presence of an ecdysteroid or a synthetic methylene lactam insecticide. Two X-ray crystallographic structures, determined at 2.7 Å resolution, show that the ligand-binding domains of both subunits of this receptor, like those of other nuclear receptors, can display significant conformational flexibility. Thermal melt experiments show that while ponasterone A stabilizes the higher order structure of the heterodimer in solution, the methylene lactam destabilizes it. The conformations of the EcR and USP subunits observed in the structure crystallized in the presence of the methylene lactam have not been seen previously in any ecdysone receptor structure and represent a new level of conformational flexibility for these important receptors. Interestingly, the new USP conformation presents an open, unoccupied ligand-binding pocket.

  20. Sublethal and transgenerational effects of insecticides in developing Trichogramma galloi (Hymenoptera: Trichogrammatidae) : toxicity of insecticides to Trichogramma galloi.

    PubMed

    Costa, Mariana Abreu; Moscardini, Valéria Fonseca; da Costa Gontijo, Pablo; Carvalho, Geraldo Andrade; de Oliveira, Rodrigo Lopes; de Oliveira, Harley Nonato

    2014-10-01

    This study assessed the transgenerational effects of insecticides in developing Trichogramma galloi (Hymenoptera: Trichogrammatidae). Laboratory bioassays were performed in which five insecticides were sprayed on egg-larval, pre-pupal and pupal stages of the parasitoid. The interaction between insecticides and development stages of the parasitoid was not significant for the rate of F0 emergence. All insecticides significantly reduced the emergence of wasps, with the lowest emergence observed when they were applied to the pupal stage. For the sex ratio, only spinosad applied to the pre-pupal stage and triflumuron applied on the egg-larval and pre-pupal stages did not differ from the controls. Triflumuron applied to pre-pupae did not lead to any difference in the parasitism rate of the treated generation (F0) when compared to the control. There were no significant differences among survival curves for females of F0 when all insecticides were sprayed on the egg-larval stage. Both concentrations of lambda-cyhalothrin + thiamethoxam reduced female pre-pupal survival, and all treatments reduced female pupal survival. In addition, we observed a transgenerational effect of the insecticides on emergence and sex ratio of next generation (F1). Lambda-cyhalothrin + thiamethoxam (Min) applied to the pre-pupae and pupae, the maximum rate of the same insecticides applied to the egg-larvae and pre-pupae, and spinosad applied to pre-pupae all significantly reduced the adults emergence of T. galloi F1 generation. Only triflumuron did not alter the F1 sex ratio. These bioassays provide a basis for better understanding the effects of insecticide use on beneficial parasitoids.

  1. Male Mosquitoes as Vehicles for Insecticide

    PubMed Central

    Mains, James W.; Brelsfoard, Corey L.; Dobson, Stephen L.

    2015-01-01

    Background The auto-dissemination approach has been shown effective at treating cryptic refugia that remain unaffected by existing mosquito control methods. This approach relies on adult mosquito behavior to spread larvicide to breeding sites at levels that are lethal to immature mosquitoes. Prior studies demonstrate that ‘dissemination stations,’ deployed in mosquito-infested areas, can contaminate adult mosquitoes, which subsequently deliver the larvicide to breeding sites. In some situations, however, preventative measures are needed, e.g., to mitigate seasonal population increases. Here we examine a novel approach that combines elements of autocidal and auto-dissemination strategies by releasing artificially reared, male mosquitoes that are contaminated with an insecticide. Methodology Laboratory and field experiments examine for model-predicted impacts of pyriproxyfen (PPF) directly applied to adult male Aedes albopictus, including (1) the ability of PPF-treated males to cross-contaminate females and to (2) deliver PPF to breeding sites. Principal Findings Similar survivorship was observed in comparisons of PPF-treated and untreated males. Males contaminated both female adults and oviposition containers in field cage tests, at levels that eliminated immature survivorship. Field trials demonstrate an ability of PPF-treated males to transmit lethal doses to introduced oviposition containers, both in the presence and absence of indigenous females. A decline in the Ae. albopictus population was observed following the introduction of PPF-treated males, which was not observed in two untreated field sites. Conclusions/Significance The results demonstrate that, in cage and open field trials, adult male Ae. albopictus can tolerate PPF and contaminate, either directly or indirectly, adult females and immature breeding sites. The results support additional development of the proposed approach, in which male mosquitoes act as vehicles for insecticide delivery

  2. The insecticidal activity and action mode of an imidacloprid analogue, 1-(3-pyridylmethyl)-2-nitroimino-imidazolidine.

    PubMed

    Zhuang, An-Xiang; Zhang, Yi-Xi; Zhang, Hui; Liu, Ze-Wen

    2016-10-01

    Neonicotinoids, such as imidacloprid, are key insecticides extensively used for control of Nilaparvata lugens. However, imidacloprid resistance has been reported in many Asian countries in recent years. To understand the roles of the chlorine atom of pyridyl group on insecticidal activity and resistance, the atom was removed to generate an imidacloprid analogue DC-Imi (DesChlorine Imidacloprid). DC-Imi showed significantly higher toxicity than imidacloprid in the susceptible strain of N. lugens, but had medium level cross-resistance in an imidacloprid-resistant strain. In Xenopus oocyte expressed nicotinic acetylcholine receptors (nAChRs) Nlα1/rβ2, the inward currents evoked by DC-Imi were detected and could be blocked by typical nAChRs antagonist dihydro-β-erythroidine (DHβE), which demonstrated that DC-Imi acted as an agonist on insect nAChRs. The efficacy of DC-Imi on Nlα1/rβ2 was 1.8-fold higher than that of imidacloprid. In addition, the influence of an imidacloprid resistance associated mutation (Y151S) on agonist potencies was evaluated. Compared with the wild-type receptor, the mutation reduced maximal inward current of DC-Imi to 55.6% and increased half maximal effective concentration (EC50 ) to 3.53-fold. Compared with imidacloprid (increasing EC50 to 2.38-fold of wild-type receptor), Y151S mutation decreased DC-Imi potency more significantly. The results indicated that the selective and possibly high toxicities could be achieved through the modification of 6-chloro-3-pyridyl group in imidacloprid and other neonicotinoids.

  3. Insecticide Mixtures Could Enhance the Toxicity of Insecticides in a Resistant Dairy Population of Musca domestica L

    PubMed Central

    Khan, Hafiz Azhar Ali; Akram, Waseem; Shad, Sarfraz Ali; Lee, Jong-Jin

    2013-01-01

    House flies, Musca domestica L., are important pests of dairy operations worldwide, with the ability to adapt wide range of environmental conditions. There are a number of insecticides used for their management, but development of resistance is a serious problem. Insecticide mixtures could enhance the toxicity of insecticides in resistant insect pests, thus resulting as a potential resistance management tool. The toxicity of bifenthrin, cypermethrin, deltamethrin, chlorpyrifos, profenofos, emamectin benzoate and fipronil were assessed separately, and in mixtures against house flies. A field-collected population was significantly resistant to all the insecticides under investigation when compared with a laboratory susceptible strain. Most of the insecticide mixtures like one pyrethroid with other compounds evaluated under two conditions (1∶1-“A” and LC50: LC50-“B”) significantly increased the toxicity of pyrethroids in the field population. Under both conditions, the combination indices of pyrethroids with other compounds, in most of the cases, were significantly below 1, suggesting synergism. The enzyme inhibitors, PBO and DEF, when used in combination with insecticides against the resistant population, toxicities of bifenthrin, cypermethrin, deltamethrin and emamectin were significantly increased, suggesting esterase and monooxygenase based resistance mechanism. The toxicities of bifenthrin, cypermethrin and deltamethrin in the resistant population of house flies could be enhanced by the combination with chlorpyrifos, profenofos, emamectin and fipronil. The findings of the present study might have practical significance for resistance management in house flies. PMID:23613758

  4. Predicted EC50 and EC95 of Remifentanil for Smooth Removal of a Laryngeal Mask Airway Under Propofol Anesthesia

    PubMed Central

    Yoo, Ji Young; Kwak, Hyun Jeong; Lee, Kyung Cheon; Kim, Go Wun

    2015-01-01

    Purpose The purpose of this study was to determine the effect-site concentration (Ce) of remifentanil in 50% of patients (EC50) and 95% of patients (EC95) for smooth laryngeal mask airway (LMA) removal in adults under propofol and remifentanil anesthesia. Materials and Methods Twenty-five patients of ASA physical status I-II and ages 18-60 years who were to undergo minor gynecological or orthopedic surgery were assessed in this study. Anesthesia was induced and maintained with propofol and remifentanil target-controlled infusion (TCI). Remifentanil was maintained at a predetermined Ce during the emergence period. The modified Dixon's up-and-down method was used to determine the remifentanil concentration, starting from 1.0 ng/mL (step size of 0.2 ng/mL). Successful removal of the LMA was regarded as absence of coughing/gagging, clenched teeth, gross purposeful movements, breath holding, laryngospasm, or desaturation to SpO2<90%. Results The mean±SD Ce of remifentanil for smooth LMA removal after propofol anesthesia was 0.83±0.16 ng/mL. Using isotonic regression with a bootstrapping approach, the estimated EC50 and EC95 of remifentanil Ce were 0.91 ng/mL [95% confidence interval (CI), 0.77-1.07 ng/mL] and 1.35 ng/mL (95% CI, 1.16-1.38 ng/mL), respectively. Conclusion Our results showed that remifentanil TCI at an established Ce is a reliable technique for achieving safe and smooth emergence without coughing, laryngospasm, or other airway reflexes. PMID:26069139

  5. Requirement of a relatively high threshold level of Mg(2+) for cell growth of a rhizoplane bacterium, Sphingomonas yanoikuyae EC-S001.

    PubMed

    Hoo, Henny; Hashidoko, Yasuyuki; Islam, Md Tofazzal; Tahara, Satoshi

    2004-09-01

    Mg(2+) is one of the essential elements for bacterial cell growth. The presence of the magnesium cation (Mg(2+)) in various concentrations often affects cell growth restoration in plant-associating bacteria. This study attempted to determine whether Mg(2+) levels in Sphingomonas yanoikuyae EC-S001 affected cell growth restoration in the host plant and what the threshold level is. S. yanoikuyae EC-S001, isolated from the rhizoplane of spinach seedlings grown from surface-sterilized seeds under aseptic conditions, displayed uniform dispersion and attachment throughout the rhizoplane and phylloplane of the host seedlings. S. yanoikuyae EC-S001 did not grow in potato-dextrose broth medium but grew well in an aqueous extract of spinach leaves. Chemical investigation of the growth factor in the spinach leaf extract led to identification of the active principle as the magnesium cation. A concentration of ca. 0.10 mM Mg(2+) or more allowed S. yanoikuyae EC-S001 to grow in potato-dextrose broth medium. Some saprophytic and/or diazotrophic bacteria used in our experiment were found to have diverse threshold levels for their Mg(2+) requirements. For example, Burkholderia cepacia EC-K014, originally isolated from the rhizoplane of a Melastoma sp., could grow even in Mg(2+)-free Hoagland's no. 2 medium with saccharose and glutamine (HSG medium) and requires a trace level of Mg(2+) for its growth. In contrast, S. yanoikuyae EC-S001, together with Bacillus subtilis IFO12113, showed the most drastic restoring responses to subsequent addition of 0.98 mM Mg(2+) to Mg(2+)-free HSG medium. Our studies concluded that Mg(2+) is more than just the essential trace element needed for cell growth restoration in S. yanoikuyae EC-S001 and that certain nonculturable bacteria may require a higher concentration of Mg(2+) or another specific essential element for their growth.

  6. Toxicity of natural insecticides on the larvae of wheat head armyworm, Dargida diffusa (Lepidoptera: Noctuidae).

    PubMed

    Reddy, Gadi V P; Antwi, Frank B

    2016-03-01

    The wheat head armyworm, Dargida (previously Faronta) diffusa (Walker) (Lepidoptera: Noctuidae), is widely distributed in North American grasslands and is most common on the Great Plains, where it is often a serious pest of corn and cereal crops. Six commercially available botanical or microbial insecticides used against D. diffusa were tested in the laboratory: Entrust(®) WP (spinosad 80%), Mycotrol(®) ESO (Beauveria bassiana GHA), Aza-Direct(®) (azadirachtin), Met52(®) EC (Metarhizium brunneum F52), Xpectro(®) OD (Beauveria bassiana GHA+pyrethrins), and Xpulse(®) OD (Beauveria bassiana GHA+azadirachtin). Concentrations of 0.1, 0.5, 1.0 and 2.0 fold the lowest labelled rates of formulated products were tested for all products, while for Entrust WP additional concentrations of 0.001 and 0.01 fold the label rates were also assessed. Survival rates were determined from larval mortality at 1-9 days post treatment application. We found that among the tested chemicals, Entrust(®) (spinosad) was the most effective, causing 83-100% mortality (0-17% survival rate) at day 3 across all concentrations. The others, in order of efficacy from most to least, were Xpectro(®) (B. bassiana GHA+pyrethrins), Xpulse(®)OD (B. bassiana GHA+azadirachtin), Aza-Direct(®) (azadirachtin), Met52(®) EC (M. brunneum F52), and Mycotrol(®) ESO (B. bassiana GHA). These products and entomopathogenic fungi caused 70-100% mortality (0-30% survivability) from days 7 to 9. The tested products and entomopathogenic fungi can be used in management of D. diffusa. PMID:26855414

  7. Tolerance to the carbamate insecticide propoxur.

    PubMed

    Costa, L G; Hand, H; Schwab, B W; Murphy, S D

    1981-01-01

    Male mice were given the carbamate insecticide propoxur (2-isopropoxy phenyl methylcarbamate; Baygon) in the drinking water at weekly increasing concentrations (from 50 to 2000 ppm), for a period of 6 weeks. At the end of the treatment the LD50 for propoxur was significantly higher in the treated animals as compared with controls. Propoxur-treated animals were also resistant to the hypothermic effect of an acute administration of the same compound. Groups of mice were challenged with the cholinergic agonist carbachol at intervals during the drinking water dosing and at its end. No differences in sensitivity to carbachol acute toxicity were found between control and treated animals. Propoxur-tolerant animals were also not resistant to the hypothermic effect of oxotremorine, another cholinergic agonist. [3H]Quinuclidinyl benzilate ([3H]QNB) binding (a measure of muscarinic receptor density and affinity) in forebrain, hindbrain and ileum never differed in control and treated mice. The possibility that repeated administrations of propoxur induced increased metabolic inactivation was tested by measuring hexobarbital sleeping time and carboxylesterase activity in treated and control mice. No changes in tissue carboxylesterase activities occurred but hexobarbital sleeping time was significantly reduced in propoxur treated animals suggesting an induction of hepatic microsomal enzymes. These results suggest that tolerance to propoxur is not mediated by a decrease of cholinergic receptors, as reported for other acetylcholinesterase inhibitors, but possibly by an enhancement of its metabolism.

  8. Federal chemist reports on insecticide dangers

    USGS Publications Warehouse

    DeWitt, J.B.

    1957-01-01

    There's been much discussion, and considerable argument, in recent years regarding the effects of crop dusting on game populations. In an attempt to get some of the answers, the U. S. Fish and Wildlife Service has been conducting a series of experiments, using captive quail? and pheasants.....By. feeding. specified amounts??of various insecticides, they found how 'much it would take to kill outright all test birds, how much to produce partIal kill, and how much would have relatively little effect. An interesting result? of the experiments was the proof that even non-fatal doses would stunt growth and reduce egg fertility, and that birds were unable to reproduce at all after two generations of exposure to these poisons....Of the cheriricals tested, aldrin and endrin were the most poisonous to the birds. If aldrin were applied at the rate of one pound per acre, each square? foot of ground would have enough poison? to kill two adult quail or 20 two-week-old birds.

  9. Insecticidal crystal proteins of Bacillus thuringiensis.

    PubMed Central

    Höfte, H; Whiteley, H R

    1989-01-01

    A classification for crystal protein genes of Bacillus thuringiensis is presented. Criteria used are the insecticidal spectra and the amino acid sequences of the encoded proteins. Fourteen genes are distinguished, encoding proteins active against either Lepidoptera (cryI), Lepidoptera and Diptera (cryII), Coleoptera (cryIII), or Diptera (cryIV). One gene, cytA, encodes a general cytolytic protein and shows no structural similarities with the other genes. Toxicity studies with single purified proteins demonstrated that every described crystal protein is characterized by a highly specific, and sometimes very restricted, insect host spectrum. Comparison of the deduced amino acid sequences reveals sequence elements which are conserved for Cry proteins. The expression of crystal protein genes is affected by a number of factors. Recently, two distinct sigma subunits regulating transcription during different stages of sporulation have been identified, as well as a protein regulating the expression of a crystal protein at a posttranslational level. Studies on the biochemical mechanisms of toxicity suggest that B. thuringiensis crystal proteins induce the formation of pores in membranes of susceptible cells. In vitro binding studies with radiolabeled toxins demonstrated a strong correlation between the specificity of B. thuringiensis toxins and the interaction with specific binding sites on the insect midgut epithelium. The expression of B. thuringiensis crystal proteins in plant-associated microorganisms and in transgenic plants has been reported. These approaches are potentially powerful strategies for the protection of agriculturally important crops against insect damage. Images PMID:2666844

  10. Intensive care management of organophosphate insecticide poisoning

    PubMed Central

    Sungur, Murat; Güven, Muhammed

    2001-01-01

    Introduction Organophosphate (OP) insecticides inhibit both cholinesterase and pseudo-cholinesterase activities. The inhibition of acetylcholinesterase causes accumulation of acetylcholine at synapses, and overstimulation of neurotransmission occurs as a result of this accumulation. The mortality rate of OP poisoning is high. Early diagnosis and appropriate treatment is often life saving. Treatment of OP poisoning consists of intravenous atropine and oximes. The clinical course of OP poisoning may be quite severe and may need intensive care management. We report our experience with the intensive care management of serious OP insecticide poisonings. Methods A retrospective study was performed on the patients with OP poisoning followed at our medical intensive care unit. Forty-seven patients were included. Diagnosis was performed from the history taken either from the patient or from the patient's relatives about the agent involved in the exposure. Diagnosis could not be confirmed with serum and red blood cell anticholinesterase levels because these are not performed at our institution. Intravenous atropine and pralidoxime was administered as soon as possible. Pralidoxime could not be given to 16 patients: 2 patients did not receive pralidoxime because they were late admissions and 14 did not receive pralidoxime because the Ministry of Health office was out of stock. Other measures for the treatment were gastric lavage and administration of activated charcoal via nasogastric tube, and cleansing the patient's body with soap and water. The patients were intubated and mechanically ventilated if the patients had respiratory failure, a depressed level of consciousness, which causes an inability to protect the airway, and hemodynamic instability. Mechanical ventilation was performed as synchronized intermittent mandatory ventilation + pressure support mode, either as volume or pressure control. Positive end expiratory pressure was titrated to keep SaO2 above 94% with 40

  11. Azobenzene Modified Imidacloprid Derivatives as Photoswitchable Insecticides: Steering Molecular Activity in a Controllable Manner

    NASA Astrophysics Data System (ADS)

    Xu, Zhiping; Shi, Lina; Jiang, Danping; Cheng, Jiagao; Shao, Xusheng; Li, Zhong

    2015-10-01

    Incorporating the photoisomerizable azobenzene into imidacloprid produced a photoswitchable insecticidal molecule as the first neonicotinoid example of remote control insecticide performance with spatiotemporal resolution. The designed photoswitchable insecticides showed distinguishable activity against Musca both in vivo and in vitro upon irradiation. Molecular docking study further suggested the binding difference of the two photoisomers. The generation of these photomediated insecticides provides novel insight into the insecticidal activity facilitating further investigation on the functions of insect nicotinic acetylcholine receptors and opens a novel way to control and study insect behavior on insecticide poisoning using light.

  12. Soil microorganisms in cotton fields sequentially treated with insecticides.

    PubMed

    Vig, K; Singh, D K; Agarwal, H C; Dhawan, A K; Dureja, P

    2008-02-01

    A crop protection system consisting of sequential treatments by six insecticides--dimethoate, monocrotophos, deltamethrin, endosulfan, cypermethrin, and triazophos--at recommended dosages in cotton fields in Punjab, India was investigated for its effects on nontarget soil microorganisms and their activities. Successive applications of the insecticides caused only short-lived adverse effects on the soil microorganisms. None of the insecticides used had any adverse effects on soil fungi as reflected by their total numbers. Significant change in Azotobacter numbers were observed after dimethoate, triazophos, and endosulfan treatment in 1998 soil. An increase of up to 71% in actinomycetes numbers was observed after deltamethrin treatment in the treated fields in 1995. Few short-term changes in iron-reduction capacity were observed after endosulfan and cypermethrin treatments. No adverse effect was observed on the soil respiration during all the experimental periods. The amount of residues detected in soil ranged from 8.5 to 42.0 ng g(-1)dry wt. soil for organophosphorus insecticides and from nondetectable to 5.55 ng g (-1)dry wt. soil for synthetic pyrethroids. It ranged between 7.3 and 35.6 ng g(-1)dry wt. soil for endosulfan. On many occasions two or three insecticide residues were detected together; therefore, the effect observed on soil microorganisms and their activities was a multiresidue effect. In 1998, crop soil amounts of insecticide residues were generally more than those in 1995 and 1996. Persistence and dissipation patterns in soils with a history of exposure to the insecticides compared to the non-history soils were similar.

  13. ANTIBACTERIAL ACTIVITY OF GUAVA (PSIDIUM GUAJAVA L.) AND NEEM (AZADIRACHTA INDICA A. JUSS.)EXTRACTS AGAINST FOOD BORNE PATHOGENS AND SPOILAGE BACTERIA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this study was to investigate the antibacterial properties of guava (Psidium guajava) and neem (Azadirachta indica) extracts against a number of common food borne pathogens and spoilage bacteria. Screening for antibacterial activity was determined by disc diffusion assay against 21...

  14. Laboratory and field evaluation of neem (Azadirachta indica A. Juss) and Chinaberry (Melia azedarach L.) oils as repellents against Phlebotomus orientalis and P. bergeroti (Diptera: Psychodidae) in Ethiopia.

    PubMed

    Kebede, Yosef; Gebre-Michael, Teshome; Balkew, Meshesha

    2010-02-01

    The study evaluated the efficacy of neem (Azadirachta indica A. Juss.) and Chinaberry (Melia azedarach L.) seed oils as repellents against laboratory and field populations of some sandflies in Ethiopia. In the laboratory, concentrations of 2% and 5% neem oil in coconut oil tested against Phlebotomus orientalis (vector of visceral leishmaniasis) provided 96.28% (95% CI=95.60-96.97) protection up to a mean time of 7h and 20 min and 98.26% (95% CI=93.46-104. 07) protection up to 9h, respectively. Similarly, M. azedarach oil at 2% concentration produced 95.13% (95% CI=90.74-99.52) protection for the same duration (7h and 20 min), while the 5% oil gave 96.20 (95% CI=86.98-105.41) protection for 8h and 20 min against the same species with no significant difference in percentage protection between the two oils at 2% and 5% concentrations. In the field tests with only neem oil (A. indica) against field populations of P. orientalis and P. bergeroti, similar high level of repellencies were recorded with about the same duration of protection. Application of both neem and Chinaberry oils can be safe and low-cost means of personal protection against sandfly bites in endemic areas of Ethiopia, if the community is advised and encouraged to grow the plants abundantly. PMID:19854142

  15. Effect of neem seed extract on feeding, growth, survival, and reproduction of Diaprepes abbreviatus (Coleoptera: Curculionidae).

    PubMed

    Weathersbee, A A; Tang, Y Q

    2002-08-01

    A commercially available neem seed extract, Neemix 4.5, containing 4.5% azadirachtin (AZA), was assessed for biological activity against the root weevil Diaprepes abbreviatus (L.), an important exotic insect pest of Florida citrus. Laboratory bioassays against neonatal and 3-wk-old larvae fed sliced carrot treated with Neemix produced dose-dependent larval mortality and reduced fresh weights among survivors of treatments. The weight response was greater than the mortality response for both larval age groups. Neonates treated with 45 mg/liter AZA weighed 60% less than those in the control after 4 wk. Three-week-old larvae treated with 45 mg/ liter AZA weighed 30% less than those in the control after 5 wk. When neonates were exposed to insect diet incorporated with Neemix, reductions in larval survival and weight were observed at concentrations as low as 4.8 mg/liter AZA after 6 wk. Larval growth was inhibited by >97% with 42.9 mg/liter AZA in the diet. A soil drench containing 30 mg/liter AZA reduced the survival and weight gain of neonates added to potted citrus and provided protection to the roots in a greenhouse experiment. A concentration of 90 mg/liter AZA was required to provide protection of citrus roots against 4-wk-old larvae. Reproductive effects were observed when adult weevils were fed foliage treated with Neemix. The numbers of larvae hatching per egg mass were reduced by 27% and 68% at 30 and 90 mg/liter AZA, respectively. These results suggest that Neemix should be further evaluated for use in integrated pest management (IPM) programs of citrus. PMID:12216804

  16. Research on Intellectual Property Conflicts Identification in Knowledge Transferring among EC Enterprises

    NASA Astrophysics Data System (ADS)

    Su, Shibin

    As the lacks of existing research about intellectual property conflicts management of EC enterprise, the paper analysis the intellectual property conflicts in knowledge transferring among EC enterprises by intellectual property types, then, the paper makes research on intellectual property conflicts identification in knowledge transferring among EC enterprises, and gives relative assumption, meanwhile, the paper makes quantities identification of intellectual property conflicts in knowledge transferring among EC enterprises by evidential theory, finally, the paper gives the further research orientations.

  17. Insecticide resistance in the bed bug comes with a cost.

    PubMed

    Gordon, Jennifer R; Potter, Michael F; Haynes, Kenneth F

    2015-01-01

    Adaptation to new environmental stress is often associated with an alteration of one or more life history parameters. Insecticide resistant populations of insects often have reduced fitness relative to susceptible populations in insecticide free environments. Our previous work showed that three populations of bed bugs, Cimex lectularius L., evolved significantly increased levels of resistance to one product containing both β-cyfluthrin and imidacloprid insecticides with only one generation of selection, which gave us an opportunity to explore potential tradeoffs between life history parameters and resistance using susceptible and resistant strains of the same populations. Life history tables were compiled by collecting weekly data on mortality and fecundity of bugs from each strain and treatment throughout their lives. Selection led to a male-biased sex ratio, shortened oviposition period, and decreased life-time reproductive rate. Generation time was shortened by selection, a change that represents a benefit rather than a cost. Using these life history characteristics we calculated that there would be a 90% return to pre-selection levels of susceptibility within 2- 6.5 generations depending on strain. The significant fitness costs associated with resistance suggest that insecticide rotation or utilization of non-insecticidal control tactics could be part of an effective resistance management strategy. PMID:26039510

  18. Insecticide resistance in the bed bug comes with a cost

    PubMed Central

    Gordon, Jennifer R.; Potter, Michael F.; Haynes, Kenneth F.

    2015-01-01

    Adaptation to new environmental stress is often associated with an alteration of one or more life history parameters. Insecticide resistant populations of insects often have reduced fitness relative to susceptible populations in insecticide free environments. Our previous work showed that three populations of bed bugs, Cimex lectularius L., evolved significantly increased levels of resistance to one product containing both β-cyfluthrin and imidacloprid insecticides with only one generation of selection, which gave us an opportunity to explore potential tradeoffs between life history parameters and resistance using susceptible and resistant strains of the same populations. Life history tables were compiled by collecting weekly data on mortality and fecundity of bugs from each strain and treatment throughout their lives. Selection led to a male-biased sex ratio, shortened oviposition period, and decreased life-time reproductive rate. Generation time was shortened by selection, a change that represents a benefit rather than a cost. Using these life history characteristics we calculated that there would be a 90% return to pre-selection levels of susceptibility within 2- 6.5 generations depending on strain. The significant fitness costs associated with resistance suggest that insecticide rotation or utilization of non-insecticidal control tactics could be part of an effective resistance management strategy. PMID:26039510

  19. Insecticide cytotoxicology in China: Current status and challenges.

    PubMed

    Zhong, Guohua; Cui, Gaofeng; Yi, Xin; Sun, Ranran; Zhang, Jingjing

    2016-09-01

    The insecticide cytotoxicology, as a new branch of toxicology, has rapidly developed in China. During the past twenty years, thousands of investigations have sprung up to evaluate the damages and clarify the mechanisms of insecticidal chemical substances to insect cells in vivo or in vitro. The mechanisms of necrosis, apoptosis or autophagy induced by synthetic or biogenic pesticides and virus infections have been systematically illuminated in many important models, including S2, BmN, SL-1, Sf21 and Sf9 cell lines. In addition, a variety of methods have also been applied to examine the effects of insecticides and elaborate the modes of action. As a result, many vital factors and pathways, such as cytochrome c, the Bcl-2 family and caspases, in mitochondrial signaling pathways, intracellular free calcium and lysosome signal pathways have been illuminated and drawn much attention. Benefiting from the application of insecticide cytotoxicology, natural products purifications, biological activities assessments of synthetic compounds and high throughput screening models have been accelerated in China. However, many questions remained, and there exist great challenges, especially in theory system, evaluation criterion, evaluation model, relationship between activity in vitro and effectiveness in vivo, and the toxicological mechanism. Fortunately, the generation of "omics" could bring opportunities for the development of insecticide cytotoxicology. PMID:27521907

  20. Insecticide susceptibility in mosquitoes (Diptera: Culicidae) from French Polynesia.

    PubMed

    Failloux, A B; Ung, A; Raymond, M; Pasteur, N

    1994-09-01

    Susceptibility to six organophosphate (OP), two pyrethroid (PY), and one carbamate (C) insecticides was investigated in Culex pipiens quinquefasciatus Say, Aedes aegypti (L.), and Aedes polynesiensis Marks larvae from the island of Tahiti. Cx. p. quinquefasciatus and Ae. aegypti were compared with susceptible reference strains treated simultaneously. A low, but significant, resistance to bromophos (4.6x), chlorpyrifos (5.7x), fenthion (2.4x), fenitrothion (5.0x), temephos (4.3x) and permethrin (2.1x) was found in Cx. p. quinquefasciatus, and to malathion (1.5x), temephos (2.3x), permethrin (1.8x) and propoxur (1.7x) in Ae. aegypti. Cx. p. quinquefasciatus was shown to possess over-produced esterases A2 and B2, which are known to be involved in resistance to OPs in other countries. Ae. polynesiensis was less resistant than the Ae. aegypti reference strain to all insecticides except temephos (1.8x) and permethrin (6.7x). To determine whether Ae. polynesiensis had developed resistance to these insecticides in Tahiti, a geographical survey covering 12 islands of the Society, Tuamotu, Tubuai, Marquesas, and Gambier archipelagoes was undertaken with three insecticides (temephos, deltamethrin, and permethrin). Two- to threefold variations in LC50S were observed among collections. Results are discussed in relationship to the level of insecticide exposure on the different islands. PMID:7966164

  1. Broken promise? Taxes and tariffs on insecticide treated mosquito nets.

    PubMed

    Alilio, Martin; Mwenesi, Halima; Barat, Lawrence M; Payes, Roshelle M; Prysor-Jones, Suzanne; Diara, Malick; McGuire, David; Shaw, Willard

    2007-12-01

    Seven years ago, the removal of taxes and tariffs on insecticide treated nets (ITNs) was considered one of the easiest resolutions for most countries to implement among the targets agreed upon at the African Summit on Roll Back Malaria in Abuja, Nigeria, on April 25, 2000. However, seven years later, 24 of the 39 Abuja signatories continue to impose taxes and tariffs on this life-saving tool. Taxes and tariffs significantly increase the price of an insecticide treated net, reduce affordability, and discourage the commercial sector from importing insecticide treated net products. Consequently, Roll Back Malaria partners are engaged in advocacy efforts to remove taxes and tariffs on insecticide treated nets in malaria-endemic countries of Africa. This viewpoint summarizes key obstacles to the removal of taxes and tariffs that have been identified through a review of country situations. To achieve the goal of producing and supplying more than 160 million insecticide treated nets needed to reach the revised Roll Back Malaria Partnership targets by 2010, tax and tariff reforms are urgently needed. Such reforms must be accompanied by country-specific systems to protect the poor (e.g., through voucher systems for vulnerable groups and other forms of targeted subsidies).

  2. The global status of insect resistance to neonicotinoid insecticides.

    PubMed

    Bass, Chris; Denholm, Ian; Williamson, Martin S; Nauen, Ralf

    2015-06-01

    The first neonicotinoid insecticide, imidacloprid, was launched in 1991. Today this class of insecticides comprises at least seven major compounds with a market share of more than 25% of total global insecticide sales. Neonicotinoid insecticides are highly selective agonists of insect nicotinic acetylcholine receptors and provide farmers with invaluable, highly effective tools against some of the world's most destructive crop pests. These include sucking pests such as aphids, whiteflies, and planthoppers, and also some coleopteran, dipteran and lepidopteran species. Although many insect species are still successfully controlled by neonicotinoids, their popularity has imposed a mounting selection pressure for resistance, and in several species resistance has now reached levels that compromise the efficacy of these insecticides. Research to understand the molecular basis of neonicotinoid resistance has revealed both target-site and metabolic mechanisms conferring resistance. For target-site resistance, field-evolved mutations have only been characterized in two aphid species. Metabolic resistance appears much more common, with the enhanced expression of one or more cytochrome P450s frequently reported in resistant strains. Despite the current scale of resistance, neonicotinoids remain a major component of many pest control programmes, and resistance management strategies, based on mode of action rotation, are of crucial importance in preventing resistance becoming more widespread. In this review we summarize the current status of neonicotinoid resistance, the biochemical and molecular mechanisms involved, and the implications for resistance management.

  3. IRAC: Mode of action classification and insecticide resistance management.

    PubMed

    Sparks, Thomas C; Nauen, Ralf

    2015-06-01

    Insecticide resistance is a long standing and expanding problem for pest arthropod control. Effective insecticide resistance management (IRM) is essential if the utility of current and future insecticides is to be preserved. Established in 1984, the Insecticide Resistance Action Committee (IRAC) is an international association of crop protection companies. IRAC serves as the Specialist Technical Group within CropLife International focused on ensuring the long term efficacy of insect, mite and tick control products through effective resistance management for sustainable agriculture and improved public health. A key function of IRAC is the continued development of the Mode of Action (MoA) classification scheme, which provides up-to-date information on the modes of action of new and established insecticides and acaricides and which serves as the basis for developing appropriate IRM strategies for crop protection and vector control. The IRAC MoA classification scheme covers more than 25 different modes of action and at least 55 different chemical classes. Diversity is the spice of resistance management by chemical means and thus it provides an approach to IRM providing a straightforward means to identify potential rotation/alternation options.

  4. Insecticide susceptibility in mosquitoes (Diptera: Culicidae) from French Polynesia.

    PubMed

    Failloux, A B; Ung, A; Raymond, M; Pasteur, N

    1994-09-01

    Susceptibility to six organophosphate (OP), two pyrethroid (PY), and one carbamate (C) insecticides was investigated in Culex pipiens quinquefasciatus Say, Aedes aegypti (L.), and Aedes polynesiensis Marks larvae from the island of Tahiti. Cx. p. quinquefasciatus and Ae. aegypti were compared with susceptible reference strains treated simultaneously. A low, but significant, resistance to bromophos (4.6x), chlorpyrifos (5.7x), fenthion (2.4x), fenitrothion (5.0x), temephos (4.3x) and permethrin (2.1x) was found in Cx. p. quinquefasciatus, and to malathion (1.5x), temephos (2.3x), permethrin (1.8x) and propoxur (1.7x) in Ae. aegypti. Cx. p. quinquefasciatus was shown to possess over-produced esterases A2 and B2, which are known to be involved in resistance to OPs in other countries. Ae. polynesiensis was less resistant than the Ae. aegypti reference strain to all insecticides except temephos (1.8x) and permethrin (6.7x). To determine whether Ae. polynesiensis had developed resistance to these insecticides in Tahiti, a geographical survey covering 12 islands of the Society, Tuamotu, Tubuai, Marquesas, and Gambier archipelagoes was undertaken with three insecticides (temephos, deltamethrin, and permethrin). Two- to threefold variations in LC50S were observed among collections. Results are discussed in relationship to the level of insecticide exposure on the different islands.

  5. Mass Spectrometric Analyses of Organophosphate Insecticide Oxon Protein Adducts

    PubMed Central

    Thompson, Charles M.; Prins, John M.; George, Kathleen M.

    2010-01-01

    Objective Organophosphate (OP) insecticides continue to be used to control insect pests. Acute and chronic exposures to OP insecticides have been documented to cause adverse health effects, but few OP-adducted proteins have been correlated with these illnesses at the molecular level. Our aim was to review the literature covering the current state of the art in mass spectrometry (MS) used to identify OP protein biomarkers. Data sources and extraction We identified general and specific research reports related to OP insecticides, OP toxicity, OP structure, and protein MS by searching PubMed and Chemical Abstracts for articles published before December 2008. Data synthesis A number of OP-based insecticides share common structural elements that result in predictable OP–protein adducts. The resultant OP–protein adducts show an increase in molecular mass that can be identified by MS and correlated with the OP agent. Customized OP-containing probes have also been used to tag and identify protein targets that can be identified by MS. Conclusions MS is a useful and emerging tool for the identification of proteins that are modified by activated organophosphate insecticides. MS can characterize the structure of the OP adduct and also the specific amino acid residue that forms the key bond with the OP. Each protein that is modified in a unique way by an OP represents a unique molecular biomarker that with further research can lead to new correlations with exposure. PMID:20056576

  6. Insecticides promote viral outbreaks by altering herbivore competition.

    PubMed

    Pan, Huipeng; Preisser, Evan L; Chu, Dong; Wang, Shaoli; Wu, Qingjun; Carriére, Yves; Zhou, Xuguo; Zhang, Youjun

    2015-09-01

    While the management of biological invasions is often characterized by a series of single-specieg decisions, invasive species exist within larger food webs. These biotic interactions can alter the impact of control/eradication programs and may cause suppression efforts to inadvertently facilitate invasion spread and impact. We document the rapid replacement of the invasive Bemisia Middle East-Asia Minor I (MEAM1) cryptic biotype by the cryptic Mediterranean (MED) biotype throughout China and demonstrate that MED is more tolerant of insecticides and a better vector of tomato yellow leaf curl virus (TYLCV) than MEAMJ. While MEAM1 usually excludes MED under natural conditions, insecticide application reverses the MEAM1-MED competitive hierarchy and allows MED to exclude MEAMI. The insecticide-mediated success of MED has led to TYLCV outbreaks throughout China. Our work strongly supports the hypothesis that insecticide use in China reverses the MEAMl-MED competitive hierarchy and allows MED to displace MEAM1 in managed landscapes. By promoting the dominance of a Bemisia species that is a competent viral vector, insecticides thus increase the spread and impact of TYLCV in heterogeneous agroecosystems. PMID:26552266

  7. Performance and carcass characteristics of guinea fowl fed on dietary Neem (Azadirachta indica) leaf powder as a growth promoter

    PubMed Central

    Singh, M. K.; Singh, S. K.; Sharma, R. K.; Singh, B.; Kumar, Sh.; Joshi, S. K.; Kumar, S.; Sathapathy, S.

    2015-01-01

    The present work aimed at studying growth pattern and carcass traits in pearl grey guinea fowl fed on dietary Neem (Azadirachta indica) leaf powder (NLP) over a period of 12 weeks. Day old guinea fowl keets (n=120) were randomly assigned to four treatment groups, each with 3 replicates. The first treatment was designated as control (T0) in which no supplement was added to the feed, while in treatments T1, T2 and T3, NLP was provided as 1, 2 and 3 g per kg of feed, respectively. The results revealed a significant increase in body weight at 12 weeks; 1229.7 for T1, 1249.8 for T2, and 1266.2 g T3 compared to 1220.0 g for the control group (P<0.05). The results also showed that the supplementation of NLP significantly increased feed intake (P≤0.05) which might be due to the hypoglycaemic activity of Neem. A significant increase was also found in the feed conversion ratio (FCR) of the treated groups over the control, showing that feeding NLP to the treated groups has lowered their residual feed efficiency. The results of the study demonstrate the beneficial effects of supplementing NLP on body weight gain and dressed yield in the treated groups in guinea fowl. NLP is, therefore, suggested to be used as a feed supplement in guinea fowl for higher profitability. PMID:27175156

  8. Improvement of sperm density in neem-oil induced infertile male albino rats by Ipomoea digitata Linn

    PubMed Central

    Mahajan, Ghanashyam Keshav; Mahajan, Raghunath Totaram; Mahajan, Arun Y.

    2015-01-01

    Aim: Investigation has been carried out to validate folkloric claim of the potential of Ipomoea digitata (ID) based on reproductive health status in experimentally induced male albino rats. Materials and Methods: Emulsified neem oil fed albino rats were orally administered root powder of ID suspended in water for the doses of 250 and 500 mg/kg body weight for 40 days. Change in organ weight, sperm density and motility, serum hormonal levels and histomorphological changes were evaluated. Results: Significant increase in the sperm density and the sperm motility (P < 0.01) along with increase in the testis, and epididymes weight in neem-oil induced infertile rats treated with ID at both dose levels. This effect is vis-à-vis to serum hormonal levels. Presence of β-sitosterol in the root of ID likely to enhance the process of spermatogenesis as it is evident from histomorphological studies. Conclusion: Results of the present investigation reveal that ID is a good candidate for the management of male infertility. PMID:26401398

  9. Performance and carcass characteristics of guinea fowl fed on dietary Neem (Azadirachta indica) leaf powder as a growth promoter.

    PubMed

    Singh, M K; Singh, S K; Sharma, R K; Singh, B; Kumar, Sh; Joshi, S K; Kumar, S; Sathapathy, S

    2015-01-01

    The present work aimed at studying growth pattern and carcass traits in pearl grey guinea fowl fed on dietary Neem (Azadirachta indica) leaf powder (NLP) over a period of 12 weeks. Day old guinea fowl keets (n=120) were randomly assigned to four treatment groups, each with 3 replicates. The first treatment was designated as control (T0) in which no supplement was added to the feed, while in treatments T1, T2 and T3, NLP was provided as 1, 2 and 3 g per kg of feed, respectively. The results revealed a significant increase in body weight at 12 weeks; 1229.7 for T1, 1249.8 for T2, and 1266.2 g T3 compared to 1220.0 g for the control group (P<0.05). The results also showed that the supplementation of NLP significantly increased feed intake (P≤0.05) which might be due to the hypoglycaemic activity of Neem. A significant increase was also found in the feed conversion ratio (FCR) of the treated groups over the control, showing that feeding NLP to the treated groups has lowered their residual feed efficiency. The results of the study demonstrate the beneficial effects of supplementing NLP on body weight gain and dressed yield in the treated groups in guinea fowl. NLP is, therefore, suggested to be used as a feed supplement in guinea fowl for higher profitability.

  10. Process optimization and kinetics of biodiesel production from neem oil using copper doped zinc oxide heterogeneous nanocatalyst.

    PubMed

    Gurunathan, Baskar; Ravi, Aiswarya

    2015-08-01

    Heterogeneous nanocatalyst has become the choice of researchers for better transesterification of vegetable oils to biodiesel. In the present study, transesterification reaction was optimized and kinetics was studied for biodiesel production from neem oil using CZO nanocatalyst. The highly porous and non-uniform surface of the CZO nanocatalyst was confirmed by AFM analysis, which leads to the aggregation of CZO nanoparticles in the form of multi layered nanostructures. The 97.18% biodiesel yield was obtained in 60min reaction time at 55°C using 10% (w/w) CZO nanocatalyst and 1:10 (v:v) oil:methanol ratio. Biodiesel yield of 73.95% was obtained using recycled nanocatalyst in sixth cycle. The obtained biodiesel was confirmed using GC-MS and (1)H NMR analysis. Reaction kinetic models were tested on biodiesel production, first order kinetic model was found fit with experimental data (R(2)=0.9452). The activation energy of 233.88kJ/mol was required for transesterification of neem oil into biodiesel using CZO nanocatalyst.

  11. Process optimization and kinetics of biodiesel production from neem oil using copper doped zinc oxide heterogeneous nanocatalyst.

    PubMed

    Gurunathan, Baskar; Ravi, Aiswarya

    2015-08-01

    Heterogeneous nanocatalyst has become the choice of researchers for better transesterification of vegetable oils to biodiesel. In the present study, transesterification reaction was optimized and kinetics was studied for biodiesel production from neem oil using CZO nanocatalyst. The highly porous and non-uniform surface of the CZO nanocatalyst was confirmed by AFM analysis, which leads to the aggregation of CZO nanoparticles in the form of multi layered nanostructures. The 97.18% biodiesel yield was obtained in 60min reaction time at 55°C using 10% (w/w) CZO nanocatalyst and 1:10 (v:v) oil:methanol ratio. Biodiesel yield of 73.95% was obtained using recycled nanocatalyst in sixth cycle. The obtained biodiesel was confirmed using GC-MS and (1)H NMR analysis. Reaction kinetic models were tested on biodiesel production, first order kinetic model was found fit with experimental data (R(2)=0.9452). The activation energy of 233.88kJ/mol was required for transesterification of neem oil into biodiesel using CZO nanocatalyst. PMID:25958133

  12. Comparative evaluation of the indigenous microbial diversity vs. drilling fluid contaminants in the NEEM Greenland ice core.

    PubMed

    Miteva, Vanya; Burlingame, Caroline; Sowers, Todd; Brenchley, Jean

    2014-08-01

    Demonstrating that the detected microbial diversity in nonaseptically drilled deep ice cores is truly indigenous is challenging because of potential contamination with exogenous microbial cells. The NEEM Greenland ice core project provided a first-time opportunity to determine the origin and extent of contamination throughout drilling. We performed multiple parallel cultivation and culture-independent analyses of five decontaminated ice core samples from different depths (100-2051 m), the drilling fluid and its components Estisol and Coasol, and the drilling chips collected during drilling. We created a collection of diverse bacterial and fungal isolates (84 from the drilling fluid and its components, 45 from decontaminated ice, and 66 from drilling chips). Their categorization as contaminants or intrinsic glacial ice microorganisms was based on several criteria, including phylogenetic analyses, genomic fingerprinting, phenotypic characteristics, and presence in drilling fluid, chips, and/or ice. Firmicutes and fungi comprised the dominant group of contaminants among isolates and cloned rRNA genes. Conversely, most Proteobacteria and Actinobacteria originating from the ice were identified as intrinsic. This study provides a database of potential contaminants useful for future studies of NEEM cores and can contribute toward developing standardized protocols for contamination detection and ensuring the authenticity of the microbial diversity in deep glacial ice.

  13. Performance and carcass characteristics of guinea fowl fed on dietary Neem (Azadirachta indica) leaf powder as a growth promoter.

    PubMed

    Singh, M K; Singh, S K; Sharma, R K; Singh, B; Kumar, Sh; Joshi, S K; Kumar, S; Sathapathy, S

    2015-01-01

    The present work aimed at studying growth pattern and carcass traits in pearl grey guinea fowl fed on dietary Neem (Azadirachta indica) leaf powder (NLP) over a period of 12 weeks. Day old guinea fowl keets (n=120) were randomly assigned to four treatment groups, each with 3 replicates. The first treatment was designated as control (T0) in which no supplement was added to the feed, while in treatments T1, T2 and T3, NLP was provided as 1, 2 and 3 g per kg of feed, respectively. The results revealed a significant increase in body weight at 12 weeks; 1229.7 for T1, 1249.8 for T2, and 1266.2 g T3 compared to 1220.0 g for the control group (P<0.05). The results also showed that the supplementation of NLP significantly increased feed intake (P≤0.05) which might be due to the hypoglycaemic activity of Neem. A significant increase was also found in the feed conversion ratio (FCR) of the treated groups over the control, showing that feeding NLP to the treated groups has lowered their residual feed efficiency. The results of the study demonstrate the beneficial effects of supplementing NLP on body weight gain and dressed yield in the treated groups in guinea fowl. NLP is, therefore, suggested to be used as a feed supplement in guinea fowl for higher profitability. PMID:27175156

  14. Effect of carbaryl (carbamate insecticide) on acetylcholinesterase activity of two strains of Daphnia magna (Crustacea, Cladocera).

    PubMed

    Toumi, Hela; Bejaoui, Mustapha; Touaylia, Samir; Burga Perez, Karen F; Ferard, Jean François

    2016-11-01

    The present study was designed to investigate the effect of carbaryl (carbamate insecticide) on the acetylcholinesterase activity in two strains (same clone A) of the crustacean cladoceran Daphnia magna. Four carbaryl concentrations (0.4, 0.9, 1.8 and 3.7 µg L(-1)) were compared against control AChE activity. Our results showed that after 48 h of carbaryl exposure, all treatments induced a significant decrease of AChE activities whatever the two considered strains. However, different responses were registered in terms of lowest observed effect concentrations (LOEC: 0.4 µg L(-1) for strain 1 and 0.9 µg L(-1) for strains 2) revealing differences in sensitivity among the two tested strains of D. magna. These results suggest that after carbaryl exposure, the AChE activity responses can be also used as a biomarker of susceptibility. Moreover, our results show that strain1 is less sensitive than strain 2 in terms of IC50-48 h of AChE activity. Comparing the EC50-48 h of standard ecotoxicity test and IC50-48 h of AChE inhibition, there is the same order of sensitivity with both strains.

  15. Enantioselective toxicity and degradation of the chiral insecticide fipronil in Scenedesmus obliguus suspension system.

    PubMed

    Qu, Han; Ma, Rui-Xue; Liu, Dong-Hui; Wang, Peng; Huang, Le-Dan; Qiu, Xing-Xu; Zhou, Zhi-Qiang

    2014-11-01

    Fipronil is an effective insecticide, but it presents highly toxic effects in nontarget aquatic organisms. The present study examined the enantioselective toxicity and degradation of fipronil enantiomers in a freshwater algae Scenedesmus obliguus suspension. There was a substantial difference in the acute toxicity of the enantiomers to S. obliguus, with 72-h median effective concentrations (EC50s) of 0.29 mg L(-1) and 1.50 mg L(-1) for the R-fipronil and S-fipronil, respectively. The influences on the concentration of chlorophyll a, chlorophyll b, and carotenoids were determined, and the effects of fipronil on the concentration of chlorophyll a and chlorophyll b were also enantioselective. The degradation of fipronil in algae suspension was enantioselective, with half-lives for R-fipronil and S-fipronil of 2.9 d and 3.2 d, respectively, and the enantiomer fraction reaching 0.65 at the day 17. The enantiomeric differences should be taken into consideration for fipronil risk assessment. PMID:25077813

  16. Effect of carbaryl (carbamate insecticide) on acetylcholinesterase activity of two strains of Daphnia magna (Crustacea, Cladocera).

    PubMed

    Toumi, Hela; Bejaoui, Mustapha; Touaylia, Samir; Burga Perez, Karen F; Ferard, Jean François

    2016-11-01

    The present study was designed to investigate the effect of carbaryl (carbamate insecticide) on the acetylcholinesterase activity in two strains (same clone A) of the crustacean cladoceran Daphnia magna. Four carbaryl concentrations (0.4, 0.9, 1.8 and 3.7 µg L(-1)) were compared against control AChE activity. Our results showed that after 48 h of carbaryl exposure, all treatments induced a significant decrease of AChE activities whatever the two considered strains. However, different responses were registered in terms of lowest observed effect concentrations (LOEC: 0.4 µg L(-1) for strain 1 and 0.9 µg L(-1) for strains 2) revealing differences in sensitivity among the two tested strains of D. magna. These results suggest that after carbaryl exposure, the AChE activity responses can be also used as a biomarker of susceptibility. Moreover, our results show that strain1 is less sensitive than strain 2 in terms of IC50-48 h of AChE activity. Comparing the EC50-48 h of standard ecotoxicity test and IC50-48 h of AChE inhibition, there is the same order of sensitivity with both strains. PMID:27428655

  17. Characterization and mosquitocidal potential of neem cake-synthesized silver nanoparticles: genotoxicity and impact on predation efficiency of mosquito natural enemies.

    PubMed

    Chandramohan, Balamurugan; Murugan, Kadarkarai; Panneerselvam, Chellasamy; Madhiyazhagan, Pari; Chandirasekar, Ramachandran; Dinesh, Devakumar; Kumar, Palanisamy Mahesh; Kovendan, Kalimuthu; Suresh, Udaiyan; Subramaniam, Jayapal; Rajaganesh, Rajapandian; Aziz, Al Thabiani; Syuhei, Ban; Alsalhi, Mohamad Saleh; Devanesan, Sandhanasamy; Nicoletti, Marcello; Wei, Hui; Benelli, Giovanni

    2016-03-01

    Mosquitoes (Diptera: Culicidae) serve as important vectors for a wide number of parasites and pathogens of huge medical and veterinary importance. Aedes aegypti is a primary dengue vector in tropical and subtropical urban areas. There is an urgent need to develop eco-friendly mosquitocides. In this study, silver nanoparticles (AgNP) were biosynthesized using neem cake, a by-product of the neem oil extraction from the seed kernels of Azadirachta indica. AgNP were characterized using a variety of biophysical methods, including UV-vis spectrophotometry, FTIR, SEM, EDX, and XRD analyses. Furthermore, the neem cake extract and the biosynthesized AgNP were tested for acute toxicity against larvae and pupae of the dengue vector Ae. aegypti. LC50 values achieved by the neem cake extract ranged from 106.53 (larva I) to 235.36 ppm (pupa), while AgNP LC50 ranged from 3.969 (larva I) to 8.308 ppm (pupa). In standard laboratory conditions, the predation efficiency of a Carassius auratus per day was 7.9 (larva II) and 5.5 individuals (larva III). Post-treatment with sub-lethal doses of AgNP, the predation efficiency was boosted to 9.2 (larva II) and 8.1 individuals (larva III). The genotoxic effect of AgNP was studied on C. auratus using the comet assay and micronucleus frequency test. DNA damage was evaluated on peripheral erythrocytes sampled at different time intervals from the treatment; experiments showed no significant damages at doses below 12 ppm. Overall, this research pointed out that neem cake-fabricated AgNP are easy to produce, stable over time, and can be employed at low dosages to reduce populations of dengue vectors, with moderate detrimental effects on non-target mosquito natural enemies. PMID:26573518

  18. Toxicity and physiological effects of neem pesticides applied to rice on the Nilaparvata lugens Stål, the brown planthopper.

    PubMed

    Senthil-Nathan, Sengottayan; Choi, Man-Young; Paik, Chae-Hoon; Seo, Hong-Yul; Kalaivani, Kandaswamy

    2009-09-01

    The effects of two different neem products (Parker Oil and Neema) on mortality, food consumption and survival of the brown planthopper, Nilaparvata lugens Stål (BPH) (Homoptera: Delphacidae) were investigated. The LC(50) (3.45 ml/L for nymph and 4.42 ml/L for adult in Parker Oil treatment; 4.18 ml/L for nymph and 5.63 ml/L for adult in Neema treatment) and LC(90) (8.72 ml/L for nymph and 11.1 ml/L for adult in Parker Oil treatment; 9.84 ml/L for nymph and 13.07 ml/L for adult in Neema treatment) were identified by probit analysis. The LC(90) (equal to recommended dose) was applied in the rice field. The effective concentration of both Parker Oil and Neema took more than 48 h to kill 80% of the N. lugens. Fourth instar nymph and adult female N. lugens were caged on rice plants and exposed to a series (both LC(50) and LC(90)) of neem concentrations. Nymph and adult female N. lugens that were chronically exposed to neem pesticides showed immediate mortality after application in laboratory experiment. The quantity of food ingested and assimilated by N. lugens on neem-treated rice plants was significantly less than on control rice plants. The results clearly indicate the neem-based pesticide (Parker Oil and Neema), containing low lethal concentration, can be used effectively to inhibit the growth and survival of N. lugens. PMID:19500844

  19. Characterization and mosquitocidal potential of neem cake-synthesized silver nanoparticles: genotoxicity and impact on predation efficiency of mosquito natural enemies.

    PubMed

    Chandramohan, Balamurugan; Murugan, Kadarkarai; Panneerselvam, Chellasamy; Madhiyazhagan, Pari; Chandirasekar, Ramachandran; Dinesh, Devakumar; Kumar, Palanisamy Mahesh; Kovendan, Kalimuthu; Suresh, Udaiyan; Subramaniam, Jayapal; Rajaganesh, Rajapandian; Aziz, Al Thabiani; Syuhei, Ban; Alsalhi, Mohamad Saleh; Devanesan, Sandhanasamy; Nicoletti, Marcello; Wei, Hui; Benelli, Giovanni

    2016-03-01

    Mosquitoes (Diptera: Culicidae) serve as important vectors for a wide number of parasites and pathogens of huge medical and veterinary importance. Aedes aegypti is a primary dengue vector in tropical and subtropical urban areas. There is an urgent need to develop eco-friendly mosquitocides. In this study, silver nanoparticles (AgNP) were biosynthesized using neem cake, a by-product of the neem oil extraction from the seed kernels of Azadirachta indica. AgNP were characterized using a variety of biophysical methods, including UV-vis spectrophotometry, FTIR, SEM, EDX, and XRD analyses. Furthermore, the neem cake extract and the biosynthesized AgNP were tested for acute toxicity against larvae and pupae of the dengue vector Ae. aegypti. LC50 values achieved by the neem cake extract ranged from 106.53 (larva I) to 235.36 ppm (pupa), while AgNP LC50 ranged from 3.969 (larva I) to 8.308 ppm (pupa). In standard laboratory conditions, the predation efficiency of a Carassius auratus per day was 7.9 (larva II) and 5.5 individuals (larva III). Post-treatment with sub-lethal doses of AgNP, the predation efficiency was boosted to 9.2 (larva II) and 8.1 individuals (larva III). The genotoxic effect of AgNP was studied on C. auratus using the comet assay and micronucleus frequency test. DNA damage was evaluated on peripheral erythrocytes sampled at different time intervals from the treatment; experiments showed no significant damages at doses below 12 ppm. Overall, this research pointed out that neem cake-fabricated AgNP are easy to produce, stable over time, and can be employed at low dosages to reduce populations of dengue vectors, with moderate detrimental effects on non-target mosquito natural enemies.

  20. Resistance to bio-insecticides or how to enhance their sustainability: a review

    PubMed Central

    Siegwart, Myriam; Graillot, Benoit; Blachere Lopez, Christine; Besse, Samantha; Bardin, Marc; Nicot, Philippe C.; Lopez-Ferber, Miguel

    2015-01-01

    After more than 70 years of chemical pesticide use, modern agriculture is increasingly using biological control products. Resistances to conventional insecticides are wide spread, while those to bio-insecticides have raised less attention, and resistance management is frequently neglected. However, a good knowledge of the limitations of a new technique often provides greater sustainability. In this review, we compile cases of resistance to widely used bio-insecticides and describe the associated resistance mechanisms. This overview shows that all widely used bio-insecticides ultimately select resistant individuals. For example, at least 27 species of insects have been described as resistant to Bacillus thuringiensis toxins. The resistance mechanisms are at least as diverse as those that are involved in resistance to chemical insecticides, some of them being common to bio-insecticides and chemical insecticides. This analysis highlights the specific properties of bio-insecticides that the scientific community should use to provide a better sustainability of these products. PMID:26150820

  1. Resistance to bio-insecticides or how to enhance their sustainability: a review.

    PubMed

    Siegwart, Myriam; Graillot, Benoit; Blachere Lopez, Christine; Besse, Samantha; Bardin, Marc; Nicot, Philippe C; Lopez-Ferber, Miguel

    2015-01-01

    After more than 70 years of chemical pesticide use, modern agriculture is increasingly using biological control products. Resistances to conventional insecticides are wide spread, while those to bio-insecticides have raised less attention, and resistance management is frequently neglected. However, a good knowledge of the limitations of a new technique often provides greater sustainability. In this review, we compile cases of resistance to widely used bio-insecticides and describe the associated resistance mechanisms. This overview shows that all widely used bio-insecticides ultimately select resistant individuals. For example, at least 27 species of insects have been described as resistant to Bacillus thuringiensis toxins. The resistance mechanisms are at least as diverse as those that are involved in resistance to chemical insecticides, some of them being common to bio-insecticides and chemical insecticides. This analysis highlights the specific properties of bio-insecticides that the scientific community should use to provide a better sustainability of these products. PMID:26150820

  2. Influence of Pyrethroid Insecticides on Sodium and Calcium Influx in Neocortical Neurons

    EPA Science Inventory

    Pyrethroid insecticides bind to voltage-gated sodium channels and modify their gating kinetics, thereby disrupting neuronal function. Using murine neocortical neurons in primary culture, we have compared the ability of 11 structurally diverse pyrethroid insecticides to evoke Na+ ...

  3. Deposition of CdSe by EC-ALE

    NASA Astrophysics Data System (ADS)

    Mathe, Mkhulu K.; Cox, Stephen M.; Flowers, Billy H.; Vaidyanathan, R.; Pham, Long; Srisook, Nattapong; Happek, Uwe; Stickney, John L.

    2004-10-01

    The optimization of a program for CdSe thin film deposition using electrochemical atomic layer epitaxy (EC-ALE) is reported. EC-ALE uses surface limited reactions, underpotential deposition, to form compound thin film deposits one atomic layer at a time on Au substrates. Cyclic voltammograms showing deposition of Cd and Se on the Au substrate were first performed to identify cycle potentials. CdSe thin films were formed using an automated flow deposition system, by alternately depositing Se and Cd atomic layers, forming a compound monolayer each cycle. In total, 200 cycle deposits were formed using a series of different potentials, to better optimize the deposition conditions. Electron probe microanalysis of the deposits showed Cd/Se ratio between 1.01 and 1.13. X-ray diffraction indicated the deposits were zinc blende, with a (1 1 1) preferred orientation. The thickness of the deposits were determined using ellipsometry, and found to be around 70 nm. AFM studies of the morphology of substrates and deposits indicated that conformal films were formed. The band gaps of the deposits was determined using UV-VIS absorption measurements, photoconductivity and reflection adsorption FTIR, and all suggested a value of 1.74 eV, consistent with literature values.

  4. Exfoliative cheilitis (EC) in AIDS: association with Candida infection.

    PubMed

    Reichart, P A; Weigel, D; Schmidt-Westhausen, A; Pohle, H D

    1997-07-01

    Forty-seven of 165 patients with AIDS (28.5%) showed exfoliative cheilitis (EC), predominantly of the lower lip (n = 37). Histologically, hyphae were revealed in 23 of 47 cases (49%). In 14 of 23 specimens the histological and microbiological findings were in accordance. Smears of the vermilion border revealed Candida albicans in half of the cases (51%); however, combinations with C. krusei, C. tropicalis and C. glabrata were also seen. Twenty of 35 patients given fluconazole either prophylactically or therapeutically showed clinical signs of oral candidiasis. Frequent moistening of the lips may result in infection of the vermilion border with Candida species; consequent desiccation of the lips will lead to scale formation and exfoliation. Smears of the vermilion border of the lower lip of 20 controls with AIDS were positive in four cases. Twenty HIV-negative controls without EC showed negative microbiological results for Candida species. Exfoliative cheilitis may be associated with Candida infection in some cases and may be considered another variant of candidiasis in AIDS patients. PMID:9234190

  5. Modeling the integration of parasitoid, insecticide, and transgenic insecticidal crop for the long-term control of an insect pest.

    PubMed

    Onstad, David W; Liu, Xiaoxia; Chen, Mao; Roush, Rick; Shelton, Anthony M

    2013-06-01

    The tools of insect pest management include host plant resistance, biological control, and insecticides and how they are integrated will influence the durability of each. We created a detailed model of the population dynamics and population genetics of the diamondback moth, Plutella xylostella L., and its parasitoid, Diadegma insulare (Cresson), to study long-term pest management in broccoli Brassica oleracea L. Given this pest's history of evolving resistance to various toxins, we also evaluated the evolution of resistance to transgenic insecticidal Bt broccoli (expressing Cry1Ac) and two types of insecticides. Simulations demonstrated that parasitism provided the most reliable, long-term control of P. xylostella populations. Use of Bt broccoli with a 10% insecticide-free refuge did not reduce the long-term contribution of parasitism to pest control. Small refuges within Bt broccoli fields can delay evolution of resistance > 30 generations if resistance alleles are rare in the pest population. However, the effectiveness of these refuges can be compromised by insecticide use. Rainfall mortality during the pest's egg and neonate stages significantly influences pest control but especially resistance management. Our model results support the idea that Bt crops and biological control can be integrated in integrated pest management and actually synergistically support each other. However, the planting and maintenance of toxin-free refuges are critical to this integration.

  6. Synthesis, insecticidal activities, and SAR studies of novel pyridylpyrazole acid derivatives based on amide bridge modification of anthranilic diamide insecticides.

    PubMed

    Wang, Bao-Lei; Zhu, Hong-Wei; Ma, Yi; Xiong, Li-Xia; Li, Yong-Qiang; Zhao, Yu; Zhang, Ji-Feng; Chen, You-Wei; Zhou, Sha; Li, Zheng-Ming

    2013-06-12

    Anthranilic diamides are one of the most important classes of modern agricultural insecticides. To discover new structure-modified compounds with high activity, series of novel carbonyl thioureas, carbonyl ureas, oxadiazoles, carbonyl thiophosphorylureas, oxadiazole-containing amides, and thiazoline-containing amides were designed through the modification of the amide bridge based on the structure of chlorantraniliprole and were synthesized, and bioassays were carried out. The compounds were characterized and confirmed by melting point, IR, (1)H NMR, and elemental analyses or HRMS. Preliminary bioassays indicated that some compounds exhibited significant insecticidal activities against oriental armyworm, diamondback moth, beet armyworm, corn borer, and mosquito. Among them, trifluoroethoxyl-containing carbonyl thiourea 20a showed best larvicidal activity against oriental armyworm, with LC50 and LC95 values of 0.1812 and 0.7767 mg/L, respectively. Meanwhile, 20c and 20e showed 86 and 57% death rates against diamondback moth at 0.005 mg/L, and the LC50 values of the two compounds were 0.0017 and 0.0023 mg/L, respectively, which were lower than that of the control chlorantraniliprole. The relationship between structure and insecticidal activity was discussed, and the HF calculation results indicated that the carbonyl thiourea moiety plays an important role in the insecticidal activity. The present work demonstrated that the trifluoroethoxyl-containing carbonyl thioureas can be used as lead compounds for further development of novel insecticides.

  7. Evaluation of the size segregation of elemental carbon (EC) emission in Europe: influence on the simulation of EC long-range transportation

    NASA Astrophysics Data System (ADS)

    Chen, Ying; Cheng, Ya-Fang; Nordmann, Stephan; Birmili, Wolfram; Denier van der Gon, Hugo A. C.; Ma, Nan; Wolke, Ralf; Wehner, Birgit; Sun, Jia; Spindler, Gerald; Mu, Qing; Pöschl, Ulrich; Su, Hang; Wiedensohler, Alfred

    2016-02-01

    Elemental Carbon (EC) has a significant impact on human health and climate change. In order to evaluate the size segregation of EC emission in the EUCAARI inventory and investigate its influence on the simulation of EC long-range transportation in Europe, we used the fully coupled online Weather Research and Forecasting/Chemistry model (WRF-Chem) at a resolution of 2 km focusing on a region in Germany, in conjunction with a high-resolution EC emission inventory. The ground meteorology conditions, vertical structure and wind pattern were well reproduced by the model. The simulations of particle number and/or mass size distributions were evaluated with observations at the central European background site Melpitz. The fine mode particle concentration was reasonably well simulated, but the coarse mode was substantially overestimated by the model mainly due to the plume with high EC concentration in coarse mode emitted by a nearby point source. The comparisons between simulated EC and Multi-angle Absorption Photometers (MAAP) measurements at Melpitz, Leipzig-TROPOS and Bösel indicated that the coarse mode EC (ECc) emitted from the nearby point sources might be overestimated by a factor of 2-10. The fraction of ECc was overestimated in the emission inventory by about 10-30 % for Russia and 5-10 % for Eastern Europe (e.g., Poland and Belarus). This incorrect size-dependent EC emission results in a shorter atmospheric life time of EC particles and inhibits the long-range transport of EC. A case study showed that this effect caused an underestimation of 20-40 % in the EC mass concentration in Germany under eastern wind pattern.

  8. Insects, Insecticides and Hormesis: Evidence and Considerations for Study

    PubMed Central

    Cutler, G. Christopher

    2013-01-01

    Insects are ubiquitous, crucial components of almost all terrestrial and fresh water ecosystems. In agricultural settings they are subjected to, intentionally or unintentionally, an array of synthetic pesticides and other chemical stressors. These ecological underpinnings, the amenability of insects to laboratory and field experiments, and our strong knowledgebase in insecticide toxicology, make the insect-insecticide model an excellent one to study many questions surrounding hormesis. Moreover, there is practical importance for agriculture with evidence of pest population growth being accelerated by insecticide hormesis. Nevertheless, insects have been underutilized in studies of hormesis. Where hormesis hypotheses have been tested, results clearly demonstrate stimulatory effects on multiple taxa as measured through several biological endpoints, both at individual and population levels. However, many basic questions are outstanding given the myriad of chemicals, responses, and ecological interactions that are likely to occur. PMID:23930099

  9. Validation of the Target Protein of Insecticidal Dihydroagarofuran Sesquiterpene Polyesters

    PubMed Central

    Lu, Lina; Qi, Zhijun; Li, Qiuli; Wu, Wenjun

    2016-01-01

    A series of insecticidal dihydroagarofuran sesquiterpene polyesters were isolated from the root bark of Chinese bittersweet (Celastrus angulatus Max). A previous study indicated that these compounds affect the digestive system of insects, and aminopeptidase N3 and V-ATPase have been identified as the most putative target proteins by affinity chromatography. In this study, the correlation between the affinity of the compounds to subunit H and the insecticidal activity or inhibitory effect on the activity of V-ATPase was analyzed to validate the target protein. Results indicated that the subunit H of V-ATPase was the target protein of the insecticidal compounds. In addition, the possible mechanism of action of the compounds was discussed. The results provide new ideas for developing pesticides acting on V-ATPase of insects. PMID:26999207

  10. Environmental fate of the insecticide cypermethrin applied as microgranular and emulsifiable concentrate formulations in sunflower cultivated field plots.

    PubMed

    Mantzos, N; Karakitsou, A; Hela, D; Konstantinou, I

    2016-01-15

    A field dissipation and transport study of the insecticide cypermethrin applied as microgranular (MG) and emulsifiable concentrate (EC) formulations has been conducted in field sunflower cultivations and bare soil plots with two different slopes (1% and 5%). The dissipation of insecticide in soil (on planting rows) was monitored for a period of 193 days. Cypermethrin residual concentrations in the upper soil layer (0-10 cm), 2 days after soil application (DASA), ranged from 0.53 to 0.73 μg g(- 1) when the maximum values were observed 7 DASA, ranged from 1.06 to 1.23 μg g(-1). The dissipation rate was better described by first-order kinetics. The average half-life in cultivated (tilled and planted) plots was 23.07 and 24.24 days for soil slopes 5% and 1%, respectively. In uncultivated (tilled but not planted) plots the respective values were 22.01 and 22.37 days. The insecticide was found below the 10 cm soil layer occasionally in few samples at low concentrations (< 0.02 μg g(- 1)). In runoff water it was detected once (7 days after foliar application, at levels below LOQ), when in sediment it was detectable for seven samplings. The maximum values were observed 7 days after foliar application, when they reached 0.097 and 0.143 μg g(-1) in cultivated plots with soil slopes 1% and 5%; and 0.394 and 0.500 μg g(-1) in uncultivated plots, respectively. The amount of cypermethrin which was transferred by the sediment remained at low levels (less than 0.01% of the totally applied active ingredient), even in plots with 5% inclination. The insecticide was detected in leaves and stems of the sunflower plants after the foliar application up to the day of harvest. On the contrary, in roots it was detectable during the whole cultivation period. No residues were detected in flowers or seeds. PMID:26439647

  11. Environmental fate of the insecticide cypermethrin applied as microgranular and emulsifiable concentrate formulations in sunflower cultivated field plots.

    PubMed

    Mantzos, N; Karakitsou, A; Hela, D; Konstantinou, I

    2016-01-15

    A field dissipation and transport study of the insecticide cypermethrin applied as microgranular (MG) and emulsifiable concentrate (EC) formulations has been conducted in field sunflower cultivations and bare soil plots with two different slopes (1% and 5%). The dissipation of insecticide in soil (on planting rows) was monitored for a period of 193 days. Cypermethrin residual concentrations in the upper soil layer (0-10 cm), 2 days after soil application (DASA), ranged from 0.53 to 0.73 μg g(- 1) when the maximum values were observed 7 DASA, ranged from 1.06 to 1.23 μg g(-1). The dissipation rate was better described by first-order kinetics. The average half-life in cultivated (tilled and planted) plots was 23.07 and 24.24 days for soil slopes 5% and 1%, respectively. In uncultivated (tilled but not planted) plots the respective values were 22.01 and 22.37 days. The insecticide was found below the 10 cm soil layer occasionally in few samples at low concentrations (< 0.02 μg g(- 1)). In runoff water it was detected once (7 days after foliar application, at levels below LOQ), when in sediment it was detectable for seven samplings. The maximum values were observed 7 days after foliar application, when they reached 0.097 and 0.143 μg g(-1) in cultivated plots with soil slopes 1% and 5%; and 0.394 and 0.500 μg g(-1) in uncultivated plots, respectively. The amount of cypermethrin which was transferred by the sediment remained at low levels (less than 0.01% of the totally applied active ingredient), even in plots with 5% inclination. The insecticide was detected in leaves and stems of the sunflower plants after the foliar application up to the day of harvest. On the contrary, in roots it was detectable during the whole cultivation period. No residues were detected in flowers or seeds.

  12. Effect of pest controlling neem (Azadirachta indica A. Juss) and mata-raton (Gliricidia sepium Jacquin) leaf extracts on emission of green house gases and inorganic-N content in urea-amended soil.

    PubMed

    Méndez-Bautista, Joaquín; Fernández-Luqueño, Fabián; López-Valdez, Fernando; Mendoza-Cristino, Reyna; Montes-Molina, Joaquín A; Gutierrez-Miceli, F A; Dendooven, L

    2009-07-01

    Extracts of neem (Azadirachta indica A. Juss.) and Gliricidia sepium Jacquin, locally known as 'mata-raton', are used to control pests of maize. Their application, however, is known to affect soil microorganisms. We investigated if these extracts affected emissions of methane (CH4), carbon dioxide (CO2) and nitrous oxide (N2O), important greenhouse gases, and dynamics of soil inorganic N. Soil was treated with extracts of neem, mata-raton or lambda-cyhalothrin, used as chemical control. The soil was amended with or without urea and incubated at 40% and 100% water holding capacity (WHC). Concentrations of ammonium (NH4+), nitrite (NO2(-)) and nitrate (NO3(-)) and emissions of CH4, CO2 and N2O were monitored for 7d. Treating urea-amended soil with extracts of neem, mata-raton or lambda-cyhalothrin reduced the emission of CO2 significantly compared to the untreated soil with the largest decrease found in the latter. Oxidation of CH4 was inhibited by extracts of neem in the unamended soil, and by neem, mata-raton and lambda-cyhalothrin in the urea-amended soil compared to the untreated soil. Neem, mata-raton and lambda-cyhalothrin reduced the N2O emission from the unamended soil incubated at 40%WHC compared to the untreated soil. Extracts of neem, mata-raton and lambda-cyhalothrin had no significant effect on dynamics of NH4(+), NO2(-) and NO(3)(-). It was found that emission of CO2 and oxidation of CH4 was inhibited in the urea-amended soil treated with extracts of neem, mata-raton and lambda-cyhalothrin, but ammonification, N2O emission and nitrification were not affected.

  13. Insecticide resistance in vector Chagas disease: evolution, mechanisms and management.

    PubMed

    Mougabure-Cueto, Gastón; Picollo, María Inés

    2015-09-01

    Chagas disease is a chronic parasitic infection restricted to America. The disease is caused by the protozoa Trypanosoma cruzi, which is transmitted to human through the feces of infected triatomine insects. Because no treatment is available for the chronic forms of the disease, vector chemical control represents the best way to reduce the incidence of the disease. Chemical control has been based principally on spraying dwellings with insecticide formulations and led to the reduction of triatomine distribution and consequent interruption of disease transmission in several areas from endemic region. However, in the last decade it has been repeatedly reported the presence triatomnes, mainly Triatoma infestans, after spraying with pyrethroid insecticides, which was associated to evolution to insecticide resistance. In this paper the evolution of insecticide resistance in triatomines is reviewed. The insecticide resistance was detected in 1970s in Rhodnius prolixus and 1990s in R. prolixus and T. infestans, but not until the 2000s resistance to pyrthroids in T. infestans associated to control failures was described in Argentina and Bolivia. The main resistance mechanisms (i.e. enhanced metabolism, altered site of action and reduced penetration) were described in the T. infestans resistant to pyrethrods. Different resistant profiles were demonstrated suggesting independent origin of the different resistant foci of Argentina and Bolivia. The deltamethrin resistance in T. infestans was showed to be controlled by semi-dominant, autosomally inherited factors. Reproductive and developmental costs were also demonstrated for the resistant T. infestans. A discussion about resistance and tolerance concepts and the persistence of T. infestans in Gran Chaco region are presented. In addition, theoretical concepts related to toxicological, evolutionary and ecological aspects of insecticide resistance are discussed in order to understand the particular scenario of pyrethroid

  14. Insecticide resistance in vector Chagas disease: evolution, mechanisms and management.

    PubMed

    Mougabure-Cueto, Gastón; Picollo, María Inés

    2015-09-01

    Chagas disease is a chronic parasitic infection restricted to America. The disease is caused by the protozoa Trypanosoma cruzi, which is transmitted to human through the feces of infected triatomine insects. Because no treatment is available for the chronic forms of the disease, vector chemical control represents the best way to reduce the incidence of the disease. Chemical control has been based principally on spraying dwellings with insecticide formulations and led to the reduction of triatomine distribution and consequent interruption of disease transmission in several areas from endemic region. However, in the last decade it has been repeatedly reported the presence triatomnes, mainly Triatoma infestans, after spraying with pyrethroid insecticides, which was associated to evolution to insecticide resistance. In this paper the evolution of insecticide resistance in triatomines is reviewed. The insecticide resistance was detected in 1970s in Rhodnius prolixus and 1990s in R. prolixus and T. infestans, but not until the 2000s resistance to pyrthroids in T. infestans associated to control failures was described in Argentina and Bolivia. The main resistance mechanisms (i.e. enhanced metabolism, altered site of action and reduced penetration) were described in the T. infestans resistant to pyrethrods. Different resistant profiles were demonstrated suggesting independent origin of the different resistant foci of Argentina and Bolivia. The deltamethrin resistance in T. infestans was showed to be controlled by semi-dominant, autosomally inherited factors. Reproductive and developmental costs were also demonstrated for the resistant T. infestans. A discussion about resistance and tolerance concepts and the persistence of T. infestans in Gran Chaco region are presented. In addition, theoretical concepts related to toxicological, evolutionary and ecological aspects of insecticide resistance are discussed in order to understand the particular scenario of pyrethroid

  15. Optimal Cotton Insecticide Application Termination Timing: A Meta-Analysis.

    PubMed

    Griffin, T W; Zapata, S D

    2016-08-01

    The concept of insecticide termination timing is generally accepted among cotton (Gossypium hirsutum) researchers; however, exact timings are often disputed. Specifically, there is uncertainty regarding the last economic insecticide application to control fruit-feeding pests including tarnished plant bug (Lygus lineolaris (Palisot de Beauvois)), boll weevil (Anthonomus grandis), bollworm (Helicoverpa zea), tobacco budworm (Heliothis virescens), and cotton fleahopper (Pseudatomoscelis seriatus). A systematic review of prior studies was conducted within a meta-analytic framework. Nine publicly available articles were amalgamated to develop an optimal timing principle. These prior studies reported 53 independent multiple means comparison field experiments for a total of 247 trial observations. Stochastic plateau theory integrated with econometric meta-analysis methodology was applied to the meta-database to determine the shape of the functional form of both the agronomic optimal insecticide termination timing and corresponding yield potential. Results indicated that current university insecticide termination timing recommendations are later than overall estimated timing suggested. The estimated 159 heat units (HU) after the fifth position above white flower (NAWF5) was found to be statistically different than the 194 HU termination used as the status quo recommended termination timing. Insecticides applied after 159 HU may have been applied in excess, resulting in unnecessary economic and environmental costs. Empirical results also suggested that extending the insecticide termination time by one unit resulted in a cotton lint yield increase of 0.27 kilograms per hectare up to the timing where the plateau began. Based on economic analyses, profit-maximizing producers may cease application as soon as 124 HU after NAWF5. These results provided insights useful to improve production systems by applying inputs only when benefits were expected to be in excess of the

  16. Optimal Cotton Insecticide Application Termination Timing: A Meta-Analysis.

    PubMed

    Griffin, T W; Zapata, S D

    2016-08-01

    The concept of insecticide termination timing is generally accepted among cotton (Gossypium hirsutum) researchers; however, exact timings are often disputed. Specifically, there is uncertainty regarding the last economic insecticide application to control fruit-feeding pests including tarnished plant bug (Lygus lineolaris (Palisot de Beauvois)), boll weevil (Anthonomus grandis), bollworm (Helicoverpa zea), tobacco budworm (Heliothis virescens), and cotton fleahopper (Pseudatomoscelis seriatus). A systematic review of prior studies was conducted within a meta-analytic framework. Nine publicly available articles were amalgamated to develop an optimal timing principle. These prior studies reported 53 independent multiple means comparison field experiments for a total of 247 trial observations. Stochastic plateau theory integrated with econometric meta-analysis methodology was applied to the meta-database to determine the shape of the functional form of both the agronomic optimal insecticide termination timing and corresponding yield potential. Results indicated that current university insecticide termination timing recommendations are later than overall estimated timing suggested. The estimated 159 heat units (HU) after the fifth position above white flower (NAWF5) was found to be statistically different than the 194 HU termination used as the status quo recommended termination timing. Insecticides applied after 159 HU may have been applied in excess, resulting in unnecessary economic and environmental costs. Empirical results also suggested that extending the insecticide termination time by one unit resulted in a cotton lint yield increase of 0.27 kilograms per hectare up to the timing where the plateau began. Based on economic analyses, profit-maximizing producers may cease application as soon as 124 HU after NAWF5. These results provided insights useful to improve production systems by applying inputs only when benefits were expected to be in excess of the

  17. First results on the insecticidal action of saponins.

    PubMed

    De Geyter, Ellen; Geelen, Danny; Smagghe, Guy

    2007-01-01

    In the search for new, natural insecticides, numerous scientists are currently trying to obtain useful compound from plants. A possibly interesting class of molecules are the saponins, a group of steroidal or triterpenoidal secondary plant metabolites with divergent biological activities. In this study, we investigated the activity of saponins against living caterpillars Spodoptera littoralis) and aphids (Acyrthosiphon pisum) via treatment on artificial diets containing different concentrations of saponins. We conclude that saponins have insecticidal activity, causing mortality and/or growth inhibition in the tested insects, although from our experiments the mode of action could not be identified. PMID:18399498

  18. Haematological parameters as bioindicators of insecticide exposure in teleosts.

    PubMed

    Singh, Narendra Nath; Srivastava, Anil Kumar

    2010-06-01

    Haematological parameters, such as erythrocyte and leucocyte count, erythrocyte indices and thrombocyte number vis-a-vis coagulation of blood has been considered bioindicators of toxicosis in fish following exposure to organochlorine, organophosphate, carbamate and pyrethroid insecticides. This review deals with the effects of insecticides on the morphology of red blood cells, total erythrocyte count, haemoglobin content, haematocrit, mean corpuscular volume, mean corpuscular haemoglobin, mean corpuscular haemoglobin concentration, erythrocyte sedimentation rate, total and differential leucocyte counts, thrombocyte count and clotting time in the peripheral blood of a number of teleosts. The review also takes stock of knowledge of the subject and explores prospects of additional research in the related area. PMID:20177774

  19. Adult vial bioassays of insecticidal toxicity against cotton fleahopper, Pseudatomoscelis seriatus (Reuter) (Hemiptera: Miridae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Glass vials coated with several technical insecticides were used to determine the contact toxicity of insecticides on adult laboratory-reared and field-collected cotton fleahopper, Pseudatomoscelis seriatus (Reuter). For the 17 insecticides evaluated for laboratory-reared cotton fleahoppers, bifent...

  20. Insecticide applications to soil contribute to the development of Burkholderia mediating insecticide resistance in stinkbugs.

    PubMed

    Tago, Kanako; Kikuchi, Yoshitomo; Nakaoka, Sinji; Katsuyama, Chie; Hayatsu, Masahito

    2015-07-01

    Some soil Burkholderia strains are capable of degrading the organophosphorus insecticide, fenitrothion, and establish symbiosis with stinkbugs, making the host insects fenitrothion-resistant. However, the ecology of the symbiotic degrading Burkholderia adapting to fenitrothion in the free-living environment is unknown. We hypothesized that fenitrothion applications affect the dynamics of fenitrothion-degrading Burkholderia, thereby controlling the transmission of symbiotic degrading Burkholderia from the soil to stinkbugs. We investigated changes in the density and diversity of culturable Burkholderia (i.e. symbiotic and nonsymbiotic fenitrothion degraders and nondegraders) in fenitrothion-treated soil using microcosms. During the incubation with five applications of pesticide, the density of the degraders increased from less than the detection limit to around 10(6)/g of soil. The number of dominant species among the degraders declined with the increasing density of degraders; eventually, one species predominated. This process can be explained according to the competitive exclusion principle using V(max) and K(m) values for fenitrothion metabolism by the degraders. We performed a phylogenetic analysis of representative strains isolated from the microcosms and evaluated their ability to establish symbiosis with the stinkbug Riptortus pedestris. The strains that established symbiosis with R. pedestris were assigned to a cluster including symbionts commonly isolated from stinkbugs. The strains outside the cluster could not necessarily associate with the host. The degraders in the cluster predominated during the initial phase of degrader dynamics in the soil. Therefore, only a few applications of fenitrothion could allow symbiotic degraders to associate with their hosts and may cause the emergence of symbiont-mediated insecticide resistance.