Sample records for napiergrass pennisetum purpureum

  1. Impediments to hybridization between Napiergrass (Pennisetum purpureum Schum.) and other Pennisetum species

    USDA-ARS?s Scientific Manuscript database

    Napiergrass (Pennisetum purpureum Schum.) is a robust, perennial, warm-season grass that grows throughout the tropical and sub-tropical regions of the world. Some genotypes have sufficient winter hardiness to survive winters in the Gulf coast region of the United States. However, germplasm with in...

  2. Seeded-yet-sterile biomass feedstocks: Kinggrass and pearl millet-napiergrass

    USDA-ARS?s Scientific Manuscript database

    Kinggrass (Pennisetum purpureum Schumach. x P. glaucum [L.] R. Br.) and Pearl Millet-Napiergrass (PMN; P. glaucum x P. purpureum) are unique among energy grasses as 'Seeded-yet-Sterile' feedstocks, derived from fertile parents capable of producing significant quantities of hybrid seed while being st...

  3. Production of napiergrass as a bioenergy feedstock under organic versus inorganic fertilization in the Southeast USA

    USDA-ARS?s Scientific Manuscript database

    Napiergrass (Pennisetum purpureum Schum.) is a high-yielding perennial biomass crop that is well adapted to the Southeast USA where poultry litter is readily available. This research was conducted to compare biomass production and nutrient utilization of napiergrass fertilized with either poultry li...

  4. Herbicide Effect on Napiergrass (Pennisetum purpureum Schum.) Control

    USDA-ARS?s Scientific Manuscript database

    The interest in napiergrass as a renewable cellulosic bio-feedstock for energy production raises concerns with potential methods of control for escaped plants and volunteer plants in successive crops. In greenhouse experiments, hexazinone, glyphosate, and imazapic were applied POST, and CO2 assimila...

  5. Evaluation of control of napiergrass (Pennisetum purpureum) with tillage and herbicides

    USDA-ARS?s Scientific Manuscript database

    Napiergrass has potential as a cellulosic biofuel crop because of its rapid growth habit in the southern US. But it is also considered as a potential invasive species as listed by the Florida Exotic Pest Plant Council. In order for field renovation, information about napiergrass control in respons...

  6. Mechanical, thermal and morphological characterisation of 3D porous Pennisetum purpureum/PLA biocomposites scaffold.

    PubMed

    Revati, R; Abdul Majid, M S; Ridzuan, M J M; Normahira, M; Mohd Nasir, N F; Rahman Y, M N; Gibson, A G

    2017-06-01

    The mechanical, thermal, and morphological properties of a 3D porous Pennisetum purpureum (PP)/polylactic acid (PLA) based scaffold were investigated. In this study, a scaffold containing P. purpureum and PLA was produced using the solvent casting and particulate leaching method. P. purpureum fibre, also locally known as Napier grass, is composed of 46% cellulose, 34% hemicellulose, and 20% lignin. PLA composites with various P. purpureum contents (10%, 20%, and 30%) were prepared and subsequently characterised. The morphologies, structures and thermal behaviours of the prepared composite scaffolds were characterised using field-emission scanning electron microscopy (FESEM), Fourier transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA). The morphology was studied using FESEM; the scaffold possessed 70-200μm-sized pores with a high level of interconnectivity. The moisture content and mechanical properties of the developed porous scaffolds were further characterised. The P. purpureum/PLA scaffold had a greater porosity factor (99%) and compression modulus (5.25MPa) than those of the pure PLA scaffold (1.73MPa). From the results, it can be concluded that the properties of the highly porous P. purpureum/PLA scaffold developed in this study can be controlled and optimised. This can be used to facilitate the construction of implantable tissue-engineered cartilage. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. In vitro degradation of a 3D porous Pennisetum purpureum/PLA biocomposite scaffold.

    PubMed

    Revati, R; Majid, M S Abdul; Ridzuan, M J M; Basaruddin, K S; Rahman Y, M N; Cheng, E M; Gibson, A G

    2017-10-01

    The in vitro degradation and mechanical properties of a 3D porous Pennisetum purpureum (PP)/polylactic acid (PLA)-based scaffold were investigated. In this study, composite scaffolds with PP to PLA ratios of 0%, 10%, 20%, and 30% were immersed in a PBS solution at 37°C for 40 days. Compression tests were conducted to evaluate the compressive strength and modulus of the scaffolds, according to ASTM F451-95. The compression strength of the scaffolds was found to increase from 1.94 to 9.32MPa, while the compressive modulus increased from 1.73 to 5.25MPa as the fillers' content increased from 0wt% to 30wt%. Moreover, field emission scanning electron microscopy (FESEM) and X-ray diffraction were employed to observe and analyse the microstructure and fibre-matrix interface. Interestingly, the degradation rate was reduced for the PLA/PP 20 scaffold, though insignificantly, this could be attributed to the improved mechanical properties and stronger fibre-matrix interface. Microstructure changes after degradation were observed using FESEM. The FESEM results indicated that a strong fibre-matrix interface was formed in the PLA/PP 20 scaffold, which reflected the addition of P. purpureum into PLA decreasing the degradation rate compared to in pure PLA scaffolds. The results suggest that the P. purpureum/PLA scaffold degradation rate can be altered and controlled to meet requirements imposed by a given tissue engineering application. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Physiological and Morphological Effects of High Water Tables on Early Growth of Giant Reed (Arundo donax), Elephant Grass (Pennisetum purpureum), Energycane and Sugarcane (Saccharum spp.)

    USDA-ARS?s Scientific Manuscript database

    Increasing demand for renewable energy sources has led to interest in high-biomass crops. Species that have been proposed as well-suited for biofuel production in the Everglades Agricultural Area (EAA) of Florida include Giant Reed (Arundo donax), Elephant Grass (Pennisetum purpureum), Energycane (S...

  9. Cloning and sequence analysis of sucrose phosphate synthase gene from varieties of Pennisetum species.

    PubMed

    Li, H C; Lu, H B; Yang, F Y; Liu, S J; Bai, C J; Zhang, Y W

    2015-03-31

    Sucrose phosphate synthase (SPS) is an enzyme used by higher plants for sucrose synthesis. In this study, three primer sets were designed on the basis of known SPS sequences from maize (GenBank: NM_001112224.1) and sugarcane (GenBank: JN584485.1), and five novel SPS genes were identified by RT-PCR from the genomes of Pennisetum spp (the hybrid P. americanum x P. purpureum, P. purpureum Schum., P. purpureum Schum. cv. Red, P. purpureum Schum. cv. Taiwan, and P. purpureum Schum. cv. Mott). The cloned sequences showed 99.9% identity and 80-88% similarity to the SPS sequences of other plants. The SPS gene of hybrid Pennisetum had one nucleotide and four amino acid polymorphisms compared to the other four germplasms, and cluster analysis was performed to assess genetic diversity in this species. Additional characterization of the SPS gene product can potentially allow Pennisetum to be exploited as a biofuel source.

  10. Comparison of silage and hay of dwarf Napier grass (Pennisetum purpureum) fed to Thai native beef bulls.

    PubMed

    Mapato, Chaowarit; Wanapat, Metha

    2018-03-23

    Both quantity and quality of forages are important in dry season feeding. Eight Thai native beef bulls were arranged in a Completely randomized design to evaluate dwarf Napier namely Sweet grass (Pennisetum purpureum cv. Mahasarakham) preserved as silage or hay on feed intake, digestibility, and rumen fermentation. The animals were fed with forage ad libitum supplemented with concentrate mixture at 1.0% of BW for 21 days; data were collected during the last 7 days. The results showed that there were differences (P < 0.05) between treatments in dry matter (DM) intake, DM digestibility, and ruminal pH, in which hay feeding gave enhanced feed intake and more favorable ruminal pH. Nevertheless, mean ruminal ammonia nitrogen, total volatile fatty acids (TVFAs), proportion of VFAs, bacterial and protozoal population, and blood urea nitrogen were similar (P > 0.05) in animals fed silage and hay. Sweet grass is better preserved as hay rather than silage.

  11. Direct Solvothermal Liquefaction of Pennisetum purpureum Biomass to Produce Biocrude Using Ethanol Solvent

    NASA Astrophysics Data System (ADS)

    Adriane Ochiai, Mikael; Marrod Cruz, Salvador; Oporto, Louiellyn; de Leon, Rizalinda

    2018-03-01

    Direct solvothermal liquefaction was used in converting the lignocellulosic biomass, Pennisetum purpureum or Napier grass using ethanol as solvent. Liquefaction of Napier grass resulted in a dark and viscous bio-crude product and exhibited promising yields (34.6377% to 48.6267%). It was determined that the effects of temperature and residence time were statistically significant with the residence time having the greatest positive effect on yield. High yields of bio-crude from Napier grass seem to occur when solvothermal temperature, residence time increased and as solids ratio decreased. However, elemental analysis showed that the bio-crude produced needs to undergo deoxygenation (O: 14.25 - 49.42%) before mixing with petroleum. For the higher heating value (HHV), the parameters observed in the study were statistically insignificant, however, temperature was determined to have the greatest positive effect on HHV. It was observed that high HHV bio-crude were produced at high temperatures, low solids ratio, and low residence times. The acquired averages for the HHV (20.0333 MJ/kg to 29.7744 MJ/kg) were all higher than the HHV of the Napier grass sample used in the study (12.9394 MJ/kg). It was observed in the study, that even though solids ratio has the least effect on both responses, the choice of solids ratio is dependent on its interaction effects with the other parameters as its effects contribute to the observed responses.

  12. Assessment of bermudagrass and bunch grasses as feedstock for conversion to ethanol.

    PubMed

    Anderson, William F; Dien, Bruce S; Brandon, Sarah K; Peterson, Joy Doran

    2008-03-01

    Research is needed to allow more efficient processing of lignocellulose from abundant plant biomass resources for production to fuel ethanol at lower costs. Potential dedicated feedstock species vary in degrees of recalcitrance to ethanol processing. The standard dilute acid hydrolysis pretreatment followed by simultaneous sacharification and fermentation (SSF) was performed on leaf and stem material from three grasses: giant reed (Arundo donax L.), napiergrass (Pennisetum purpureum Schumach.), and bermudagrass (Cynodon spp). In a separate study, napiergrass, and bermudagrass whole samples were pretreated with esterase and cellulose before fermentation. Conversion via SSF was greatest with two bermudagrass cultivars (140 and 122 mg g(-1) of biomass) followed by leaves of two napiergrass genotypes (107 and 97 mg g(-1)) and two giant reed clones (109 and 85 mg g(-1)). Variability existed among bermudagrass cultivars for conversion to ethanol after esterase and cellulase treatments, with Tifton 85 (289 mg g) and Coastcross II (284 mg g(-1)) being superior to Coastal (247 mg g(-1)) and Tifton 44 (245 mg g(-1)). Results suggest that ethanol yields vary significantly for feedstocks by species and within species and that genetic breeding for improved feedstocks should be possible.

  13. Assessment of Bermudagrass and Bunch Grasses as Feedstock for Conversion to Ethanol

    NASA Astrophysics Data System (ADS)

    Anderson, William F.; Dien, Bruce S.; Brandon, Sarah K.; Peterson, Joy Doran

    Research is needed to allow more efficient processing of lignocellulose from abundant plant biomass resources for production to fuel ethanol at lower costs. Potential dedicated feedstock species vary in degrees of recalcitrance to ethanol processing. The standard dilute acid hydrolysis pretreatment followed by simultaneous sacharification and fermentation (SSF) was performed on leaf and stem material from three grasses: giant reed (Arundo donax L.), napiergrass (Pennisetum purpureum Schumach.), and bermudagrass (Cynodon spp). In a separate study, napiergrass, and bermudagrass whole samples were pretreated with esterase and cellulose before fermentation. Conversion via SSF was greatest with two bermudagrass cultivars (140 and 122 mg g-1 of biomass) followed by leaves of two napiergrass genotypes (107 and 97 mg g-1) and two giant reed clones (109 and 85 mg g-1). Variability existed among bermudagrass cultivars for conversion to ethanol after esterase and cellulase treatments, with Tifton 85 (289 mg g) and Coastcross II (284 mg g-1) being superior to Coastal (247 mg g-1) and Tifton 44 (245 mg g-1). Results suggest that ethanol yields vary significantly for feedstocks by species and within species and that genetic breeding for improved feedstocks should be possible.

  14. Bioremoval of lead using Pennisetum purpureum augmented with Enterobacter cloacae-VITPASJ1: A pot culture approach.

    PubMed

    Das, Anamika; Belgaonkar, Priyanka; Raman, Aditya S; Banu, Sofia; Osborne, Jabez W

    2017-06-01

    Lead is a toxic heavy metal discharged into the ecosystem from various industries. Biological remediation strategies have been effective in the bioremoval of lead. In our current study, a phytobacterial system using Pennisetum purpureum along with lead-resistant bacterium (LRB) was employed for the uptake of lead. The LRB was obtained from lead-contaminated sites. The isolate VITPASJ1 was found to be highly tolerant to lead and was identified as an effective plant growth-promoting bacterium. The 16S rRNA sequencing revealed VITPASJ1 to be the closest neighbour of Enterobacter cloacae. The lead-resistant gene pbrA in the plant and the bacterium were amplified using a specific primer. The uptake of lead was studied by phytoremediation and rhizoremediation set-ups where the soil was supplemented with various concentrations of lead (50, 100, 150 mg/kg). The plants were uprooted at regular intervals, and the translocation of lead into the plant was determined by atomic absorption spectroscopy. The root length, shoot height and chlorophyll content were found to be higher in the rhizoremediation set-up when compared to the phytoremediation set-up. The scanning electron microscopic micrographs gave a clear picture of increased tissue damage in the root and shoot of the phytoremediation set-up as compared to the rhizoremediation set-up with LRB.

  15. Ethanol production from sugars obtained during enzymatic hydrolysis of elephant grass (Pennisetum purpureum, Schum.) pretreated by steam explosion.

    PubMed

    Scholl, Angélica Luisi; Menegol, Daiane; Pitarelo, Ana Paula; Fontana, Roselei Claudete; Zandoná Filho, Arion; Ramos, Luiz Pereira; Dillon, Aldo José Pinheiro; Camassola, Marli

    2015-09-01

    In this work, steam explosion was used a pretreatment method to improve the conversion of elephant grass (Pennisetum purpureum) to cellulosic ethanol. This way, enzymatic hydrolysis of vaccum-drained and water-washed steam-treated substrates was carried out with Penicillium echinulatum enzymes while Saccharomyces cerevisiae CAT-1 was used for fermentation. After 48 h of hydrolysis, the highest yield of reducing sugars was obtained from vaccum-drained steam-treated substrates that were produced after 10 min at 200 °C (863.42 ± 62.52 mg/g). However, the highest glucose yield was derived from water-washed steam-treated substrates that were produced after 10 min at 190 °C (248.34 ± 6.27 mg/g) and 200 °C (246.00 ± 9.60 mg/g). Nevertheless, the highest ethanol production was obtained from water-washed steam-treated substrates that were produced after 6 min at 200 °C. These data revealed that water washing is a critical step for ethanol production from steam-treated elephant grass and that pretreatment generates a great deal of water soluble inhibitory compounds for hydrolysis and fermentation, which were partly characterized as part of this study. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Copper tolerance of the biomass crops Elephant grass (Pennisetum purpureum Schumach), Vetiver grass (Vetiveria zizanioides) and the upland reed (Phragmites australis) in soil culture.

    PubMed

    Liu, Xinghua; Shen, Yixing; Lou, Laiqing; Ding, Chenglong; Cai, Qingsheng

    2009-01-01

    Pot trials were conducted to study the influence of copper (Cu) on the growth and biomass of Elephant grass (EG, Pennisetum purpureum Schumach), Vetiver grass (VG, Vetiveria zizanioides) and the upland reed (UR, Phragmites australis). Cu toxicity in EG, VG and UR was positively correlated with the total and bioavailable Cu concentrations in the soil. Based on the EC50, dry weights, Cu contents, chlorophyll contents and photosynthesis rates, the Cu tolerance of the three species followed the trend EGNVGNUR. There were no significant differences in the unit calorific values among the different plants, though the total calorific values of EG were higher than those of VG and UR due to its higher biomass. The addition of KH2PO4 to the soil decreased the bioavailability of Cu and the Cu uptake by plants. EG could therefore be a good candidate for growth on Cu-contaminated soils, especially those improved by phosphate.

  17. Energy utilization, nitrogen balance and microbial protein supply in cattle fed Pennisetum purpureum and condensed tannins.

    PubMed

    Piñeiro-Vázquez, A T; Canul-Solis, J R; Alayón-Gamboa, J A; Chay-Canul, A J; Ayala-Burgos, A J; Solorio-Sánchez, F J; Aguilar-Pérez, C F; Ku-Vera, J C

    2017-02-01

    The aim of the experiment was to assess the effect of condensed tannins (CT) on feed intake, dry matter digestibility, nitrogen balance, supply of microbial protein to the small intestine and energy utilization in cattle fed a basal ration of Pennisetum purpureum grass. Five heifers (Bos taurus × Bos indicus) with an average live weight of 295 ± 19 kg were allotted to five treatments consisting of increasing levels of CT (0, 1, 2, 3 and 4% CT/kg DM) in a 5 × 5 Latin square design. Dry matter intake (DMI) was similar (p > 0.05) between treatments containing 0, 1, 2 and 3% of CT/kg DM and it was reduced (p < 0.05) to 4% CT (5.71 kg DM/day) with respect to that observed with 0% CT (6.65 kg DM/day). Nitrogen balance, purine derivatives excretion in urine, microbial protein synthesis and efficiency of synthesis of microbial nitrogen in the rumen were not affected (p ≥ 0.05) by the increase in the levels of condensed tannins in the ration. Energy loss as CH 4 was on average 2.7% of the gross energy consumed daily. Metabolizable energy intake was 49.06 MJ/day in cattle fed low-quality tropical grass with a DMI of 6.27 kg/day. It is concluded that concentrations of CT between 2 and 3% of DM of ration reduced energy loss as CH 4 by 31.3% and 47.6%, respectively, without affecting intakes of dry and organic matter; however, digestibilities of dry and organic matter are negatively affected. Journal of Animal Physiology and Animal Nutrition © 2016 Blackwell Verlag GmbH.

  18. New roughage source of Pennisetum purpureum cv. Mahasarakham utilization for ruminants feeding under global climate change.

    PubMed

    Wanapat, Metha; Mapato, Chaowarit

    2018-05-31

    As the climate changes, it influences ruminant's feed intake, nutrient digestibility, rumen methane production and emission. This experiment aimed to evaluate the effect of feeding Sweet grass (Pennisetum purpureum cv. Mahasarakham) as a new source of good quality forage to improve feed utilization efficiency and to mitigate rumen methane production and emission. Four, growing crossbred of Holstein Friesian heifers, 14 months old, were arranged in a 4 x 4 Latin square design to receive four dietary treatments. Treatment 1 (T1) was rice straw (RS) fed on ad libitum with 1.0 % BW of concentrate (C) supplementation (RS/1.0C). Treatment 2 (T2) and treatment 3 (T3) were Sweet grass (SG), fed on ad libitum with 1.0 and 0.5 %BW of concentrate supplementation, respectively (SG/1.0C and SG/0.5C, respectively). Treatment 4 (T4) was total Sweet grass fed on ad libitum basis with non-concentrate supplementation (TSG). The results revealed that roughage and total feed intake were increased with SG when compared to RS (P<0.01) while TSG was similar to RS/1.0C treatment. Digestibility of nutrients, nutrients intake, total VFAs, rumen microorganisms were the highest and CH4 was the lowest in the heifers received SG/1.0C (P<0.01). Total DM feed intake, digestibility and intake of nutrients, total VFAs, NH3-N, bacterial and fungal population of animals receiving SG/0.5C were higher than those fed on RS/1.0C. Reducing of concentrate supplementation with SG as a roughage source increased NH3-N, acetic acid, and fungal populations, but it decreased propionic acid and protozoal populations (P<0.05). However, ruminal pH and blood urea nitrogen were not affected by the dietary treatments (P>0.05). As the results, Sweet grass could be a good forage to improve rumen fermentation, decrease methane production and reduced the level of concentrate supplementation for growing ruminants in the tropics especially under global climate change.

  19. Combined different dehydration pretreatments and torrefaction to upgrade fuel properties of hybrid pennisetum (Pennisetum americanum ×P. purpureum).

    PubMed

    Yu, Yan; Wang, Guanghui; Bai, Xiaopeng; Liu, Jude; Wang, Decheng; Wang, Zhiqin

    2018-05-16

    Different dehydrating methods combined with torrefaction were investigated to find the underlying mechanism that how dehydration process influence the degree of hornification. Hybrid pennisetum was selected as the experiment material. Oven-dried sample (ODS), crushed dried sample (CDS), and sun-cured dried sample (SDS) were torrefied under the temperature of 275 °C and 300 °C with the duration time of 60 min. The results showed that, changes in elevated carbon content and higher heating value (HHV) and reduced oxygen content of SDS were the most obvious under identical torrefaction conditions. Fuel ratio of SDS was enhanced most under 300 °C. It also had the highest devolatilization index (D i ). The combination of sun-cured dried with torrefaction under 300 °C caused lowest degree of irreversible hornification happened during dehydrating process, and different hornification degrees caused by different dehydrating methods effect the enhancement of fuel properties of lignocellulosic biomass material. Copyright © 2018 Elsevier Ltd. All rights reserved.

  20. 7 CFR 319.41 - Notice of quarantine.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...), grain sorghums (Andropogon sorghum), Sudan grass (Andropogon sorghum sudanensis), Johnson grass... (Pennisetum glaucum), napier grass (Pennisetum purpureum), teosinte (Euchlaena luxurians), and jobs-tears...

  1. 7 CFR 319.41 - Notice of quarantine.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...), grain sorghums (Andropogon sorghum), Sudan grass (Andropogon sorghum sudanensis), Johnson grass... (Pennisetum glaucum), napier grass (Pennisetum purpureum), teosinte (Euchlaena luxurians), and jobs-tears...

  2. 40 CFR 721.10141 - Oils, ginger, zingiber purpureum.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Oils, ginger, zingiber purpureum. 721... Substances § 721.10141 Oils, ginger, zingiber purpureum. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as oils, ginger, zingiber purpureum (PMN P-06...

  3. 40 CFR 721.10141 - Oils, ginger, zingiber purpureum.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Oils, ginger, zingiber purpureum. 721... Substances § 721.10141 Oils, ginger, zingiber purpureum. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as oils, ginger, zingiber purpureum (PMN P-06...

  4. 40 CFR 721.10141 - Oils, ginger, zingiber purpureum.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Oils, ginger, zingiber purpureum. 721... Substances § 721.10141 Oils, ginger, zingiber purpureum. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as oils, ginger, zingiber purpureum (PMN P-06...

  5. 40 CFR 721.10141 - Oils, ginger, zingiber purpureum.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Oils, ginger, zingiber purpureum. 721... Substances § 721.10141 Oils, ginger, zingiber purpureum. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as oils, ginger, zingiber purpureum (PMN P-06...

  6. 40 CFR 721.10141 - Oils, ginger, zingiber purpureum.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Oils, ginger, zingiber purpureum. 721... Substances § 721.10141 Oils, ginger, zingiber purpureum. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as oils, ginger, zingiber purpureum (PMN P-06...

  7. Effects of delayed winter harvest on biomass yield and quality of napiergrass and energycane

    USDA-ARS?s Scientific Manuscript database

    Napiergrass (Cenchrus purpureus Schumach) and energycane (Saccharum hyb.) are high-yielding perennial grasses that are well-suited for biomass production in the southeast USA. The purpose of this study was to determine the effects of delayed winter harvest on biomass yield and quality of these two ...

  8. Optimization of delignification of two Pennisetum grass species by NaOH pretreatment using Taguchi and ANN statistical approach.

    PubMed

    Mohaptra, Sonali; Dash, Preeti Krishna; Behera, Sudhanshu Shekar; Thatoi, Hrudayanath

    2016-01-01

    In the bioconversion of lignocelluloses for bioethanol, pretreatment seems to be the most important step which improves the elimination of the lignin and hemicelluloses content, exposing cellulose to further hydrolysis. The present study discusses the application of dynamic statistical techniques like the Taguchi method and artificial neural network (ANN) in the optimization of pretreatment of lignocellulosic biomasses such as Hybrid Napier grass (HNG) (Pennisetum purpureum) and Denanath grass (DG) (Pennisetum pedicellatum), using alkali sodium hydroxide. This study analysed and determined a parameter combination with a low number of experiments by using the Taguchi method in which both the substrates can be efficiently pretreated. The optimized parameters obtained from the L16 orthogonal array are soaking time (18 and 26 h), temperature (60°C and 55°C), and alkali concentration (1%) for HNG and DG, respectively. High performance liquid chromatography analysis of the optimized pretreated grass varieties confirmed the presence of glucan (47.94% and 46.50%), xylan (9.35% and 7.95%), arabinan (2.15% and 2.2%), and galactan/mannan (1.44% and 1.52%) for HNG and DG, respectively. Physicochemical characterization studies of native and alkali-pretreated grasses were carried out by scanning electron microscopy and Fourier transformation Infrared spectroscopy which revealed some morphological differences between the native and optimized pretreated samples. Model validation by ANN showed a good agreement between experimental results and the predicted responses.

  9. Physiological and morphological effects of high water tables on early growth of giant reed ( Arundo donax), elephant grass ( Pennisetum purpureum), energycane and sugarcane ( Saccharum spp.)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jennewein, Stephen Peter

    Here, an increasing demand for renewable energy sources has spurred interest in high-biomass crops used for energy production. Species potentially well-suited for biofuel production in the seasonally wet organic Everglades Agricultural Area (EAA) of Florida include giant reed ( Arundo donax), elephant grass ( Pennisetum Purpureum), energycane ( Saccharum spp.), and sugarcane ( Saccharum spp.). The objectives in this study were to evaluate the role of fluctuating water tables on the morphology, physiology, and early season growth of these four genotypes. The candidate genotypes were grown in a greenhouse under three water table depths, defined by distance of the watermore » table from the soil surface: two constant water tables (-16 cm and -40 cm) along with a flood cycle (2 weeks of flood to the soil level followed by 2 weeks at -40 cm from the soil level). The genotypes included CP 89-2143 (sugarcane), L 79-1002 (energycane), Merkeron (elephant grass), and wild type (giant reed). The experiment was repeated for plant cane, first ratoon, and successive plant cane crop cycles. Reductions in dry matter yield were observed among genotypes subjected to the -40 cm drained, periodically flooded (40F) water table relative to the -40 cm constant (40C) or -16 cm constant (16C). Plant cane dry weights were reduced by 37% in giant reed, 52% in elephant grass, 42% in energycane, and 34% in sugarcane in the 40F compared to 40C water table treatments. Similarly, in the first ratoon crop dry weights were reduced by 29% in giant reed, 42% in elephant grass, 27% in energycane, and 62% in sugarcane. In plant cane and successive plant cane, average total dry weight was greatest for elephant grass whereas ratoon total dry weight was greatest for energycane. Genotype had more pronounced effects on physiological attributes than water table including the highest stomatal conductance and SPAD values in giant reed, and the highest stalk populations in elephant grass and energycane

  10. Suitability of multipurpose trees, shrubs and grasses to rehabilitate gullies in the sub-humid tropics

    NASA Astrophysics Data System (ADS)

    Talema, Ayalew; Muys, Bart; Poesen, Jean; Padro, Roc; Dibaba, Hirko; Diels, Jan

    2017-04-01

    Vegetation plays a vital role for sustainable rehabilitation of degraded lands. However, the selection of suitable and effective plant species remains a long-lasting challenge in most parts of the sub-humid tropics. To address this challenge 18 multipurpose plant species (6 trees, 3 shrubs and 9 grasses), preselected from the regional species pool in Southwest Ethiopia were planted in severely degraded gullies and monitored from July 2011 to June 2014. The experiment had a split-plot design with farmyard manure (FYM) application, as main plot and plant species as sub-plot factors repeated in three blocks. The study revealed that grasses were the most successful to rehabilitate the gully within the monitoring period, compared to trees and shrubs. The survival rate of the four most successful grass species, Chrysopogon zizanioides, Pennisetum macrourum, Pennisetum polystachion and Pennisetum purpureum ranged from 61 to 90% with FYM application and from 20 to 85% without FYM, while most of the well-known indigenous and exotic trees and shrubs failed to survive. For the grass Pennisetum purpureum, shoot height, shoot and root dry biomass increased by 300%, 342% and 578% respectively due to FYM application, with a remarkably higher response to FYM compared to all the other studied species. The overall results demonstrate that severely degraded lands can be effectively restored by using early successional species such as locally adapted and selected grasses before the plantation of trees and shrubs.

  11. Molecular markers shared by diverse apomictic Pennisetum species.

    PubMed

    Lubbers, E L; Arthur, L; Hanna, W W; Ozias-Akins, P

    1994-11-01

    Two molecular markers, a RAPD (randomly amplified polymorphic DNA) and a RFLP/STS (restriction fragment length polymorphism/sequence-tagged site), previously were found associated with apomictic reproductive behavior in a backcross population produced to transfer apomixis from Pennisetum squamulatum to pearl millet. The occurrence of these molecular markers in a range of 29 accessions of Pennisetum comprising 11 apomictic and 8 sexual species was investigated. Both markers were specific for apomictic species in Pennisetum. The RFLP/STS marker, UGT 197, was found to be associated with all taxa that displayed apomictic reproductive behavior except those in section Brevivalvula. Neither UGT197 nor the cloned RAPD fragment OPC-04600 hybridized with any sexually reproducing representatives of the genus. The cloned C04600 was associated with 3 of the 11 apomictic species, P. ciliare, P. massaicum, and P. squamulatum. UGT197 was more consistently associated with apomictic reproductive behavior than OPC04600 or cloned C04600, thus it could be inferred that UGT197 is more closely linked to the gene(s) for apomixis than the cloned C04600. The successful use of these probes to survey other Pennisetum species indicates that apomixis is a trait that can be followed across species by using molecular means. This technique of surveying species within a genus will be useful in determining the relative importance of newly isolated markers and may facilitate the identification of the apomixis gene(s).

  12. Development of innovative technique that may be used as models for the increase of biomass production with grasses and other species

    NASA Astrophysics Data System (ADS)

    Burton, G. W.; Hanna, W. W.

    1981-09-01

    Techniques for biomass increase are discussed: irradiation breeding of sterile triploid turf bermuda grasses; irradiation breeding of sterile Coastcross-1, a forage grass hybrid to increase winter hardiness; heterosis resulting from crossing specific irradiation induced mutants with their normal inbred parent; use of mitomycin and streptomycin to create cytoplasmic male sterile mutants in pearl millet; biomass of napiergrass; evaluation of mutagen induced lignin mutants to maximize metabolizable energy in sorghum; interspecific crosses in Pennisetum; production of homozygous translocation tester stocks; use of radiation to induce and transfer reproductive behavior in plants; and genetics of radiation induced mutations.

  13. Breeding Increases the Efficacy of Chondrostereum purpureum in the Sprout Control of Birch

    PubMed Central

    Hamberg, Leena; Vartiamäki, Henna; Hantula, Jarkko

    2015-01-01

    We tested whether the pairing of selected isolates could be used to increase the efficiency of a decay fungus Chondrostereum purpureum (Pers. Ex Fr.) Pouzar to control hardwood sprouting in Finland. We paired C. purpureum strains efficient in sprout control or highly active in laccase production, and tested the efficacy of their progeny in spout control experiments. This procedure resulted in a strain with an efficacy superior to that of the parental strains. The mortality of birch (Betula pendula Roth. and B. pubescens Ehrh.) 1 cm in stump diameter was 78%, 56% and 9% for the best progeny, the best parental strain and the control, respectively. Mortality was only slightly higher for B. pendula than for B. pubescens but no significant differences were found between the number or maximum height of stump sprouts. Our results showed that cross breeding of this decay fungus is a good alternative in attempts to produce efficient biocontrol agents against hardwood sprouting. PMID:25674794

  14. Breeding increases the efficacy of Chondrostereum purpureum in the sprout control of birch.

    PubMed

    Hamberg, Leena; Vartiamäki, Henna; Hantula, Jarkko

    2015-01-01

    We tested whether the pairing of selected isolates could be used to increase the efficiency of a decay fungus Chondrostereum purpureum (Pers. Ex Fr.) Pouzar to control hardwood sprouting in Finland. We paired C. purpureum strains efficient in sprout control or highly active in laccase production, and tested the efficacy of their progeny in spout control experiments. This procedure resulted in a strain with an efficacy superior to that of the parental strains. The mortality of birch (Betula pendula Roth. and B. pubescens Ehrh.) 1 cm in stump diameter was 78%, 56% and 9% for the best progeny, the best parental strain and the control, respectively. Mortality was only slightly higher for B. pendula than for B. pubescens but no significant differences were found between the number or maximum height of stump sprouts. Our results showed that cross breeding of this decay fungus is a good alternative in attempts to produce efficient biocontrol agents against hardwood sprouting.

  15. Improving methane production from anaerobic digestion of Pennisetum Hybrid by alkaline pretreatment.

    PubMed

    Kang, Xihui; Sun, Yongming; Li, Lianhua; Kong, Xiaoying; Yuan, Zhenhong

    2018-05-01

    Alkaline pretreatment with NaOH was used to improve methane yield from Pennisetum Hybrid. The pretreatments were carried out with different NaOH solutions (2-8% w/w) at three temperatures (35, 55 and 121 °C) for different periods of time (24, 24 and 1 h). All treated and untreated Pennisetum Hybrid were digested under mesophilic conditions (37 °C) to biogas, significant effects of the pretreatments on the yield of methane were observed. Results showed the modified Gompertz equation was reliable (determination coefficients (R 2 ) greater than 0.96) to describe the kinetic behavior of anaerobic digestion of Pennisetum Hybrid. The best result, obtained by the treatment at 35 °C 2% NaOH for 24 h, resulted in the methane yield of 301.7 mL/g VS, corresponding to 21.0% improvement in the methane yield. Compositional, SEM, XRD and FTIR analysis confirmed that lignin removal, structural modification and cellulose crystalline variation were responsible for the improvement. Copyright © 2018 Elsevier Ltd. All rights reserved.

  16. Evaluation of the efficacy of Hylotelephium purpureum gel in the treatment of experimental periodontitis

    PubMed Central

    Wang, Xiaofeng; Wang, Wei; Li, Wei; Niu, Zhiduo; Wang, Qing; Zhang, Dianwen; Li, Hui; Wang, Jincheng

    2018-01-01

    Local drug delivery systems have been proposed for the treatment of periodontitis, and Hylotelephium purpureum may be a suitable agent for use in such a system. The present study aimed to formulate a Hylotelephium purpureum gel (HPG) and evaluate the anti-inflammatory activity and antinociceptive effects of Hylotelephium purpureum and to assess the duration of action and efficacy of HPG in the treatment of experimental periodontitis in a KM mouse model. First, an acute toxicity study was performed, and secondly, xylene-induced mouse-ear edema, acetic acid-induced mouse peritoneal capillary permeability and carrageenan-induced hind-paw edema tests were used to investigate the anti-inflammatory activity of the gel. The acetic acid-induced writhing response and hot-plate tests were used to evaluate the antinociceptive activity. The therapeutic effects of HPG in experimental periodontitis were evaluated and minimum inhibitory concentration of the gel was determined. The results showed that intragastrically administration of 80 ml/kg of HPG produced no toxic effects. There were statistically significant changes in gingival indexes and sulcus bleeding indexes in the high-dose HPG-treated group. The serum levels of superoxide dismutase and glutathione peroxidase were significantly heightened, while the level of malondialdehyde was decreased. HPG exhibited 32.7% inhibition of edema, and altered the peritoneal capillary permeability in mice. The gel had relatively good bacteriostatic and bactericidal effects. It also exhibited antinociceptive activity, as demonstrated by the acetic acid-induced writhing response test and hot-plate test. In summary, the present study demonstrates that HPG is effective in the treatment of experimental periodontitis. PMID:29541459

  17. How will Mahanarva spectabilis (Hemiptera: Cercopidae) Respond to Global Warming?

    PubMed Central

    Auad, A. M.; Resende, T. T.; Hott, M. C.; Borges, C.A.V.

    2016-01-01

    The aim of this study was to determine the favorable constant temperature range for Mahanarva spectabilis (Distant) (Hemiptera: Cercopidae) development as well as to generate geographic distribution maps of this insect pest for future climate scenarios. M. spectabilis eggs were reared on two host plants (Brachiaria ruziziensis (Germain and Edvard) and Pennisetum purpureum (Schumach)), with individual plants kept at temperatures of 16, 20, 24, 28, and 32°C. Nymphal stage duration, nymphal survival, adult longevity, and egg production were recorded for each temperature*host plant combination. Using the favorable temperature ranges for M. spectabilis development, it was possible to generate geographic distribution. Nymphal survival was highest at 24.4°C, with estimates of 44 and 8% on Pennisetum and Brachiaria, respectively. Nymphal stage duration was greater on Brachiaria than on Pennisetum at 20 and 24°C but equal at 28°C. Egg production was higher on Pennisetum at 24 and 28°C than at 20°C, and adult longevity on Pennisetum was higher at 28°C than at 20°C, whereas adult longevity at 24°C did not differ from that at 20 and 28°C. With these results, it was possible to predict a reduction in M. spectabilis densities in most regions of Brazil in future climate scenarios. PMID:27012869

  18. How will Mahanarva spectabilis (Hemiptera: Cercopidae) Respond to Global Warming?

    PubMed

    Fonseca, M G; Auad, A M; Resende, T T; Hott, M C; Borges, C A V

    2016-01-01

    The aim of this study was to determine the favorable constant temperature range for Mahanarva spectabilis(Distant) (Hemiptera: Cercopidae) development as well as to generate geographic distribution maps of this insect pest for future climate scenarios. M. spectabilis eggs were reared on two host plants (Brachiaria ruziziensis(Germain and Edvard) and Pennisetum purpureum(Schumach)), with individual plants kept at temperatures of 16, 20, 24, 28, and 32 °C. Nymphal stage duration, nymphal survival, adult longevity, and egg production were recorded for each temperature*host plant combination. Using the favorable temperature ranges for M. spectabilis development, it was possible to generate geographic distribution. Nymphal survival was highest at 24.4 °C, with estimates of 44 and 8% on Pennisetum and Brachiaria, respectively. Nymphal stage duration was greater on Brachiaria than on Pennisetum at 20 and 24 °C but equal at 28 °C. Egg production was higher on Pennisetum at 24 and 28 °C than at 20 °C, and adult longevity on Pennisetum was higher at 28 °C than at 20 °C, whereas adult longevity at 24 °C did not differ from that at 20 and 28 °C. With these results, it was possible to predict a reduction in M. spectabilis densities in most regions of Brazil in future climate scenarios. © The Author 2016. Published by Oxford University Press on behalf of the Entomological Society of America.

  19. Phylogenetic studies favour the unification of Pennisetum, Cenchrus and Odontelytrum (Poaceae): a combined nuclear, plastid and morphological analysis, and nomenclatural combinations in Cenchrus.

    PubMed

    Chemisquy, M Amelia; Giussani, Liliana M; Scataglini, María A; Kellogg, Elizabeth A; Morrone, Osvaldo

    2010-07-01

    Twenty-five genera having sterile inflorescence branches were recognized as the bristle clade within the x = 9 Paniceae (Panicoideae). Within the bristle clade, taxonomic circumscription of Cenchrus (20-25 species), Pennisetum (80-140) and the monotypic Odontelytrum is still unclear. Several criteria have been applied to characterize Cenchrus and Pennisetum, but none of these has proved satisfactory as the diagnostic characters, such as fusion of bristles in the inflorescences, show continuous variation. A phylogenetic analysis based on morphological, plastid (trnL-F, ndhF) and nuclear (knotted) data is presented for a representative species sampling of the genera. All analyses were conducted under parsimony, using heuristic searches with TBR branch swapping. Branch support was assessed with parsimony jackknifing. Based on plastid and morphological data, Pennisetum, Cenchrus and Odontelytrum were supported as a monophyletic group: the PCO clade. Only one section of Pennisetum (Brevivalvula) was supported as monophyletic. The position of P. lanatum differed among data partitions, although the combined plastid and morphology and nuclear analyses showed this species to be a member of the PCO clade. The basic chromosome number x = 9 was found to be plesiomorphic, and x = 5, 7, 8, 10 and 17 were derived states. The nuclear phylogenetic analysis revealed a reticulate pattern of relationships among Pennisetum and Cenchrus, suggesting that there are at least three different genomes. Because apomixis can be transferred among species through hybridization, its history most likely reflects crossing relationships, rather than multiple independent appearances. Due to the consistency between the present results and different phylogenetic hypotheses (including morphological, developmental and multilocus approaches), and the high support found for the PCO clade, also including the type species of the three genera, we propose unification of Pennisetum, Cenchrus and Odontelytrum

  20. Phylogenetic studies favour the unification of Pennisetum, Cenchrus and Odontelytrum (Poaceae): a combined nuclear, plastid and morphological analysis, and nomenclatural combinations in Cenchrus

    PubMed Central

    Chemisquy, M. Amelia; Giussani, Liliana M.; Scataglini, María A.; Kellogg, Elizabeth A.; Morrone, Osvaldo

    2010-01-01

    Backgrounds and Aims Twenty-five genera having sterile inflorescence branches were recognized as the bristle clade within the x = 9 Paniceae (Panicoideae). Within the bristle clade, taxonomic circumscription of Cenchrus (20–25 species), Pennisetum (80–140) and the monotypic Odontelytrum is still unclear. Several criteria have been applied to characterize Cenchrus and Pennisetum, but none of these has proved satisfactory as the diagnostic characters, such as fusion of bristles in the inflorescences, show continuous variation. Methods A phylogenetic analysis based on morphological, plastid (trnL-F, ndhF) and nuclear (knotted) data is presented for a representative species sampling of the genera. All analyses were conducted under parsimony, using heuristic searches with TBR branch swapping. Branch support was assessed with parsimony jackknifing. Key Results Based on plastid and morphological data, Pennisetum, Cenchrus and Odontelytrum were supported as a monophyletic group: the PCO clade. Only one section of Pennisetum (Brevivalvula) was supported as monophyletic. The position of P. lanatum differed among data partitions, although the combined plastid and morphology and nuclear analyses showed this species to be a member of the PCO clade. The basic chromosome number x = 9 was found to be plesiomorphic, and x = 5, 7, 8, 10 and 17 were derived states. The nuclear phylogenetic analysis revealed a reticulate pattern of relationships among Pennisetum and Cenchrus, suggesting that there are at least three different genomes. Because apomixis can be transferred among species through hybridization, its history most likely reflects crossing relationships, rather than multiple independent appearances. Conclusions Due to the consistency between the present results and different phylogenetic hypotheses (including morphological, developmental and multilocus approaches), and the high support found for the PCO clade, also including the type species of the three genera, we propose

  1. Cultivation of the culinary-medicinal Lung Oyster mushroom, Pleurotus pulmonarius (Fr.) Quél. (Agaricomycetideae) on grass plants in Taiwan.

    PubMed

    Liang, Zeng-Chin; Wu, Kuan-Jzen; Wang, Jinn-Chyi; Lin, Chorng-Horng; Wu, Chiu-Yeh

    2011-01-01

    Cultivation of the culinary-medicinal Lung Oyster mushroom, Pleurotus pulmonarius, on the stalks of three grass plants, i.e., Panicum repens, Pennisetum purpureum, and Zea mays were investigated. The effects of various combinatorial substrates on mushroom mycelial growth and yield calculated as biological efficiency (BE) were determined. Among 9 experimental substrates, the most suitable substrate for mycelial growth was 45ZMS:45S, followed by 45PRS:45S; their mycelial growth rates were obviously quicker than that of the control substrate. The BEs of all the experimental substrates respectively containing P. repens stalk, P. purpureum stalk and Z. mays stalk were higher than that of the control (39.55%) during the 2.5 months of cultivation period. The best substrate in terms of BE was 60ZMS:30S (58.33%), followed by 45PRS:45S (57.16%), 45ZMS:45S (49.86%), and 30ZMS:60S (47.20%). Based on the BE of the tested substrates, Z mays stalk appeared to be the best alternative material for the production of P. pulmonarius.

  2. Phosphate limitation promotes unsaturated fatty acids and arachidonic acid biosynthesis by microalgae Porphyridium purpureum.

    PubMed

    Su, Gaomin; Jiao, Kailin; Li, Zheng; Guo, Xiaoyi; Chang, Jingyu; Ndikubwimana, Theoneste; Sun, Yong; Zeng, Xianhai; Lu, Yinghua; Lin, Lu

    2016-07-01

    Polyunsaturated fatty acids (PUFAs) are highly appreciated on their nutritive value for human health and aquaculture. P. purpureum, one of the red microalgae acknowledged as a promising accumulator of ARA, was chosen as the target algae in the present research. Effects of sodium bicarbonate (0.04-1.2 g/L), temperature (25, 30 and 33 °C) and phosphate (0.00-0.14 g/L) on biomass yield, total fatty acids (TFA) and arachidonic acid (ARA) accumulation were investigated systemically. NaHCO3 dose of 0.8 g/L and moderate temperature of 30 °C were preferred. In addition, TFA and ARA production were significantly enhanced by an appropriate concentration of phosphate, and the highest TFA yield of 666.38 mg/L and ARA yield of 159.74 mg/L were obtained at a phosphate concentration of 0.035 g/L. Interestingly, with phosphate concentration continuing to fall, UFA/TFA and ARA/EPA ratios were increased accordingly, suggesting that phosphate limitation promoted unsaturated fatty acids and arachidonic acid biosynthesis. Low concentration of phosphate may be favored to increase the enzymatic activities of ∆6-desaturase, which played a key role in catalyzing the conversion of C16:0 to C18:2, and thus the selectivity of UFA increased. Meanwhile, the increase of ARA selectivity could be attributed to ω6 pathway promotion and ∆17-desaturase activity inhibition with phosphate limitation. Phosphate limitation strategy enhanced unsaturated fatty acids and ARA biosynthesis in P. purpureum, and can be applied in commercial scale manufacturing and commercialization of ARA.

  3. Effects of plant growth-promoting bacteria isolated from copper tailings on plants in sterilized and non-sterilized tailings.

    PubMed

    Liu, Weiqiu; Yang, Chao; Shi, Si; Shu, Wensheng

    2014-02-01

    Ten strains of Cu-tolerant bacteria with potential plant growth-promoting ability were isolated by selecting strains with the ability to use 1-aminocyclopropane-1-carboxylate as a sole nitrogen source (designated ACC-B) or fix nitrogen (designated FLN-B) originating from the rhizosphere of plants growing on copper tailings. All 10 strains proved to have intrinsic ability to produce indole acetic acid and siderophores, and most of them could mobilize insoluble phosphate. In addition, a greenhouse study showed that ACC-B, FLN-B and a mixture of both had similar, potent ability to stimulate growth of Pennisetum purpureum, Medicago sativa and Oenothera erythrosepala plants grown on sterilized tailings. For instance, above-ground biomass of P. purpureum was 278-357% greater after 60d growth on sterilized tailings in their presence. They could also significantly promote the growth of the plants grown on non-sterilized tailings, though the growth-promoting effects were much weaker. So, strategies for using of the plant growth-promoting bacteria in the practice of phytoremediation deserve further studies to get higher growth-promoting efficiency. Copyright © 2013 Elsevier Ltd. All rights reserved.

  4. In Silico and Fluorescence In Situ Hybridization Mapping Reveals Collinearity between the Pennisetum squamulatum Apomixis Carrier-Chromosome and Chromosome 2 of Sorghum and Foxtail Millet.

    PubMed

    Sapkota, Sirjan; Conner, Joann A; Hanna, Wayne W; Simon, Bindu; Fengler, Kevin; Deschamps, Stéphane; Cigan, Mark; Ozias-Akins, Peggy

    2016-01-01

    Apomixis, or clonal propagation through seed, is a trait identified within multiple species of the grass family (Poaceae). The genetic locus controlling apomixis in Pennisetum squamulatum (syn Cenchrus squamulatus) and Cenchrus ciliaris (syn Pennisetum ciliare, buffelgrass) is the apospory-specific genomic region (ASGR). Previously, the ASGR was shown to be highly conserved but inverted in marker order between P. squamulatum and C. ciliaris based on fluorescence in situ hybridization (FISH) and varied in both karyotype and position of the ASGR on the ASGR-carrier chromosome among other apomictic Cenchrus/Pennisetum species. Using in silico transcript mapping and verification of physical positions of some of the transcripts via FISH, we discovered that the ASGR-carrier chromosome from P. squamulatum is collinear with chromosome 2 of foxtail millet and sorghum outside of the ASGR. The in silico ordering of the ASGR-carrier chromosome markers, previously unmapped in P. squamulatum, allowed for the identification of a backcross line with structural changes to the P. squamulatum ASGR-carrier chromosome derived from gamma irradiated pollen.

  5. In Silico and Fluorescence In Situ Hybridization Mapping Reveals Collinearity between the Pennisetum squamulatum Apomixis Carrier-Chromosome and Chromosome 2 of Sorghum and Foxtail Millet

    PubMed Central

    Sapkota, Sirjan; Conner, Joann A.; Hanna, Wayne W.; Simon, Bindu; Fengler, Kevin; Deschamps, Stéphane; Cigan, Mark; Ozias-Akins, Peggy

    2016-01-01

    Apomixis, or clonal propagation through seed, is a trait identified within multiple species of the grass family (Poaceae). The genetic locus controlling apomixis in Pennisetum squamulatum (syn Cenchrus squamulatus) and Cenchrus ciliaris (syn Pennisetum ciliare, buffelgrass) is the apospory-specific genomic region (ASGR). Previously, the ASGR was shown to be highly conserved but inverted in marker order between P. squamulatum and C. ciliaris based on fluorescence in situ hybridization (FISH) and varied in both karyotype and position of the ASGR on the ASGR-carrier chromosome among other apomictic Cenchrus/Pennisetum species. Using in silico transcript mapping and verification of physical positions of some of the transcripts via FISH, we discovered that the ASGR-carrier chromosome from P. squamulatum is collinear with chromosome 2 of foxtail millet and sorghum outside of the ASGR. The in silico ordering of the ASGR-carrier chromosome markers, previously unmapped in P. squamulatum, allowed for the identification of a backcross line with structural changes to the P. squamulatum ASGR-carrier chromosome derived from gamma irradiated pollen. PMID:27031857

  6. Implications of biomass pretreatment to cost and carbon emissions: case study of rice straw and Pennisetum in Taiwan.

    PubMed

    Chiueh, Pei-Te; Lee, Kun-Chou; Syu, Fu-Sians; Lo, Shang-Lien

    2012-03-01

    The purpose of this study was to explore the impact of feedstock collection and torrefaction pretreatment on the efficiency of a biomass co-firing system. Considering the transformation of existing municipal solid waste incinerators, several scenarios in which biomass supply chains depend on centralised pretreatment and transportation alternatives are presented. The cost, net energy output, and greenhouse gas effects of these scenarios were analysed using a spreadsheet model. Based on the Taoyuan County case in Taiwan, the mitigation costs of carbon emissions for rice straw and Pennisetum are 77.0 $/Mg CO(2) and 63.8 $/Mg CO(2), respectively. Results indicate that transporting feedstock from its source to the pretreatment and co-firing stations contributes the most to logistical costs for both straw and Pennisetum, regardless of whether torrefaction was adopted. Nonetheless, torrefaction requires more demonstrated cases at various scales to obtain the technical and economic data required for further analysis. Copyright © 2012 Elsevier Ltd. All rights reserved.

  7. Higher iron pearl millet (Pennisetum glaucum L.) provides more absorbable iron that is limited by increased polyphenolic content

    USDA-ARS?s Scientific Manuscript database

    Background: Our objective was to compare the capacity of iron (Fe) biofortified and standard pearl millet (Pennisetum glaucum L.) to deliver Fe for hemoglobin (Hb) synthesis. Pearl millet is the most widely grown type of millet. It is common primarily in West Africa and the Indian subcontinent, and ...

  8. Development of innovative techniques and principles that may be used as models to improve plant performance. Progress report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hanna, W.W.; Burton, G.W.

    1984-06-01

    Dominant immunity to rust (Puccinia) and Piricularia leaf spot, a new stable A/sub 1/ cytoplasm and yield genes have been discovered in a single accession of P. monodii, a subspecies of pearl millet Pennisetum americanum. The useful genes were transferred to the best pearl millet inbreds using a backcrossing and screening system enhanced by controlling daylength, temperature, and breaking seed dormancy. Genes for fertility restoration, plant morphology, head characteristics and grain yield were transferred from the A' genome of P. purpureum (secondary gene pool) to pearl millet. This was made possible by doubling the chromosome number of the sterile triploidmore » between pearl millet and P. purpureum to produce fertile hexaploids. A number of hexaploids were backcrossed to pearl millet to find hexaploids that produced A' gametes to produce AA' 2n = 14 pearl millet plants. The value of the genes on the A' genome were not recognized before the AA' plants were produced because the B genome masked the characteristics on the A' genome in P. purpureum. In the tertiary gene pool, male and female fertile apomictic BC/sub 1/ plants were produced between pearl millet and P. orientale or P. squamulatum by manipulating chromosome levels or by producing trispecific hybrids. The development of fertile backcross plants in this gene pool is encouraging for further germplasm transfer research with emphasis on apomixis. The cytoplasm of P. schweinfurthii has been transferred to pearl millet. Mutations for early maturity and daylength insensitivity induced with mutagens have resulted in the development and release of early maturing inbreds Tift 23A/sub 1/E/sub 1/ and Tift 23B/sub 1/E/sub 1/.« less

  9. Bioactivity of Essential Oil of Zingiber purpureum Rhizomes and Its Main Compounds against Two Stored Product Insects.

    PubMed

    Wang, Y; You, C X; Yang, K; Wu, Y; Chen, R; Zhang, W J; Liu, Z L; Du, S S; Deng, Z W; Geng, Z F; Han, J

    2015-06-01

    The insecticidal and repellent activities of the essential oil extracted from Zingiber purpureum Roscoe rhizomes were evaluated against Tribolium castaneum (Herbst) and Lasioderma serricorne (L.) adults. During our screening program for agrochemicals from Chinese medicinal herbs and wild plants, the essential oil of Z. purpureum rhizomes was found to possess strong contact toxicity against T. castaneum and L. serricorne adults, with LD50 values of 39.0 and 16.3 µg per adult, respectively, and also showed strong fumigant toxicity against the two grain storage insects with LC50 values of 13.6 and 9.3 mg/liter of air, respectively. The essential oil obtained by hydrodistillation was investigated by gas chromatography-mass spectrometry. The main components of the essential oil were identified to be sabinene (48.1%), terpinen-4-ol (25.1%), and γ-terpinene (6.7%), followed by α-terpinene (4.3%), β-thujene (3.4%), and α-phellandrene (2.7%). Sabinene, terpinen-4-ol, and γ-terpinene were separated and purified by silica gel column chromatography and preparative thin-layer chromatography. Terpinen-4-ol showed the strongest contact toxicity against T. castaneum and L. serricorne (LD50=19.7 and 5.4 µg per adult, respectively) and also the strongest fumigant toxicity against T. castaneum and L. serricorne (LC50=3.7 and 1.3 mg/liter of air, respectively). Otherwise, sabinene and terpinen-4-ol were strongly repellent against T. castaneum as well as the essential oil, while γ-terpinene exhibited weaker repellency against T. castaneum compared with the positive control, DEET (N, N-diethyl-3-methylbenzamide). Moreover, only the essential oil exhibited strong repellency against L. serricorne, the three compounds exhibited weaker repellency against L. serricorne relative to DEET. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  10. Short Communication: An apospory-specific genomic region is conserved between Buffelgrass (Cenchrus ciliaris L.) and Pennisetum squamulatum Fresen.

    PubMed

    Roche; Cong; Chen; Hanna; Gustine; Sherwood; Ozias-Akins

    1999-07-01

    Twelve molecular markers linked to pseudogamous apospory, a form of gametophytic apomixis, were previously isolated from Pennisetum squamulatum Fresen. No recombination between these markers was found in a segregating population of 397 individuals (Ozias-Akins et al. 1998, Proc. Natl Acad. Sci. USA, 95, 5127-5132). The objective of the present study was to test if these markers were also linked to the aposporous mode of reproduction in two small segregating populations of Cenchrus ciliaris (= Pennisetum ciliare (L.)Link), another apomictic grass species. Among 12 markers (sequence characterized amplified regions, SCARs), six were scored as dominant markers between aposporous and sexual C. ciliaris genotypes (presence/absence, respectively). Five were always linked to apospory and one showed a low level of recombination in 84 progenies. Restriction fragment length polymorphisms (RFLPs) were observed between sexual and apomictic phenotypes for three of the six remaining SCARs from P. squamulatum when used as probes. No recombination was observed in the F1 progenies. Preliminary data from megabase DNA analysis and sequencing in both species indicate that an apospory-specific genomic region (ASGR) is highly conserved between the two species. Although C. ciliaris has a smaller genome size to P. squamulatum, a higher copy number for markers linked to apospory found in the former may impair the progress of positional cloning of gene(s) for apomixis in this species.

  11. Biotechnological application of sustainable biogas production through dry anaerobic digestion of Napier grass.

    PubMed

    Dussadee, Natthawud; Ramaraj, Rameshprabu; Cheunbarn, Tapana

    2017-05-01

    Napier grass (Pennisetum purpureum), represents an interesting substrate for biogas production. The research project evaluated biogas potential production from dry anaerobic digestion of Napier grass using batch experiment. To enhance the biogas production from ensiled Napier grass, thermal and alkaline pre-treatments were performed in batch mode. Alkali hydrolysis of Napier grass was performed prior to batch dry anaerobic digestion at three different mild concentrations of sodium hydroxide (NaOH). The study results confirmed that NaOH pretreated sample produced high yield of biogas than untreated (raw) and hot water pretreated samples. Napier grass was used as the mono-substrate. The biogas composition of carbon dioxide (30.10%), methane (63.50%) and 5 ppm of H 2 S was estimated from the biogas. Therefore, fast-growing, high-yielding and organic matter-enriched of Napier grass was promising energy crop for biogas production.

  12. Tight clustering and hemizygosity of apomixis-linked molecular markers in Pennisetum squamulatum implies genetic control of apospory by a divergent locus that may have no allelic form in sexual genotypes

    PubMed Central

    Ozias-Akins, Peggy; Roche, Dominique; Hanna, Wayne W.

    1998-01-01

    Apomixis is a naturally occurring mode of reproduction that results in embryo formation without the involvement of meiosis or fertilization of the egg. Seed-derived progeny of an apomictic plant are genetically identical to the maternal parent. We are studying a form of apomixis called apospory that occurs in the genus Pennisetum, a taxon in the grass family. A cultivated member of this genus, pearl millet (Pennisetum glaucum), reproduces sexually. A wild relative of pearl millet, Pennisetum squamulatum, that is an obligate aposporous species, is cross-compatible with pearl millet when used as a pollen donor in the interspecific cross. We present herein the genetic mapping of 13 molecular markers in an interspecific hybrid population of 397 individuals that segregates for apomixis and sexuality. Surprisingly, 12 of the 13 markers strictly cosegregated with aposporous embryo sac development, clearly defining a contiguous apospory-specific genomic region in which no genetic recombination was detected. Lack of or suppression of recombination may be coincidentally associated with the chromosomal context of the apomixis locus or it may be a consequence of its evolution that is essential for preservation of gene function as has been previously shown in studies of complex loci in both plant and animal species. PMID:9560240

  13. The impact of an invasive African bunchgrass (Pennisetum setaceum) on water availability and productivity of canopy trees within a tropical dry forest in Hawaii

    Treesearch

    Susan Cordell; D. R. Sandquist

    2008-01-01

    Tropical dry forests are among the Earth's most threatened ecosystems. On the Island of Hawaii the African bunchgrass Pennisetum setaceum (fountain grass) dominates the understorey of the few remaining fragments of native dry forests and is contributing to the degradation of this once diverse ecosystem. In this study, we...

  14. Biogas production from anaerobic codigestion of cowdung and elephant grass (Pennisetum Purpureum) using batch digester

    NASA Astrophysics Data System (ADS)

    Haryanto, Agus; Hasanudin, Udin; Afrian, Chandra; Zulkarnaen, Iskandar

    2018-03-01

    This study aimed at determining biogas production from codigestion of Elephant grass and cowdung using batch digester. Fresh grass was manually chopped with a maximum length of 3 cm. Chopped grass (25 kg) was perfectly mixed with fresh cowdung (25 kg). The mixture was introduced into a 220-liter batch drum digester. The substrate was diluted with water at different rates (P1 = 50 L, P2 = 75 L, and P3 = 100 L) and was stirred thoroughly. Six digesters were prepared as duplicate for each treatment. Two other digesters containing only 25 kg cowdung diluted with 25 L water were also provided as control treatment (P0). The digesters were air tightly sealed for 70 days. Observation was conducted on daily temperature, substrate pH (initial and final), TS and VS content, biogas yield and biogas composition. Results showed that final pH of grass containing substrate was in the acidic range, namely 4.50, 4.62, 6.82, whereas that of control (P0) was normal with pH of 7.30. Digester with substrate composition 25:25:100 (cowdung:grass:water) produced the highest biogas total (524.3 L). Biogas yield of codigestion, however, was much lower as compared to that of control, namely 7.35, 16.75, and 111.72 L/kg VS r respectively for treatment P1, P2, P3. with dilution rate of 50, 75, and 100 L. Biogas produced from control digester had methane content of 53.88%. In contrast, biogas resulted from all treatments contained low methane (the highest was 31.37%). Methane yield of 39.3 L/kg TS removal was achieved from digester with dilution 100 L (P3). Mechanical pretreatment is suggested to break Elephant grass down into smaller particles prior to introducing it into the digestion process.

  15. Capacity and mechanisms of ammonium and cadmium sorption on different wetland-plant derived biochars.

    PubMed

    Cui, Xiaoqiang; Hao, Hulin; Zhang, Changkuan; He, Zhenli; Yang, Xiaoe

    2016-01-01

    The objective of this study was to investigate the relationship between Cd(2+)/NH4(+) sorption and physicochemical properties of biochars produced from different wetland plants. Biochars from six species of wetland plants (i.e., Canna indica, Pennisetum purpureum Schum, Thalia dealbata, Zizania caduciflora, Phragmites australis and Vetiveria zizanioides) were obtained at 500°C and characterized, and their sorption for ammonium and cadmium was determined. There were significant differences in elemental composition, functional groups and specific surface area among the biochars derived from different wetland plant species. Sorption of ammonium and cadmium on the biochars could be described by a pseudo second order kinetic model, and the simple Langmuir model fits the isotherm data better than the Freundlich or Temkin model. The C. indica derived biochar had the largest sorption capacity for NH4(+) and Cd(2+), with a maximum sorption of 13.35 and 125.8mgg(-1), respectively. P. purpureum Schum derived biochar had a similar maximum sorption (119.3mgg(-1)) for Cd(2+). Ammonium sorption was mainly controlled by cation exchange, surface complexation with oxygen-containing functional groups and the formation of magnesium ammonium phosphate compounds, whereas for Cd(2+) sorption, the formation of cadmium phosphate precipitates, cation exchange and binding to oxygen-containing groups were the major possible mechanisms. In addition, the sorption of ammonium and cadmium was not affected by surface area and microporosity of the biochars. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. Exogenous calcium induces tolerance to atrazine stress in Pennisetum seedlings and promotes photosynthetic activity, antioxidant enzymes and psbA gene transcripts.

    PubMed

    Erinle, Kehinde Olajide; Jiang, Zhao; Ma, Bingbing; Li, Jinmei; Chen, Yukun; Ur-Rehman, Khalil; Shahla, Andleeb; Zhang, Ying

    2016-10-01

    Calcium (Ca) has been reported to lessen oxidative damages in plants by upregulating the activities of antioxidant enzymes. However, atrazine mediated reactive oxygen species (ROS) reduction by Ca is limited. This study therefore investigated the effect of exogenously applied Ca on ROS, antioxidants activity and gene transcripts, the D1 protein (psbA gene), and chlorophyll contents in Pennisetum seedlings pre-treated with atrazine. Atrazine toxicity increased ROS production and enzyme activities (ascorbate peroxidase APX, peroxidase POD, Superoxide dismutase SOD, glutathione-S-transferase GST); but decreased antioxidants (APX, POD, and Cu/Zn SOD) and psbA gene transcripts. Atrazine also decreased the chlorophyll contents, but increased chlorophyll (a/b) ratio. Contrarily, Ca application to atrazine pre-treated seedlings lowered the harmful effects of atrazine by reducing ROS levels, but enhancing the accumulation of total chlorophyll contents. Ca-protected seedlings in the presence of atrazine manifested reduced APX and POD activity, whereas SOD and GST activity was further increased with Ca application. Antioxidant gene transcripts that were down-regulated by atrazine toxicity were up-regulated with the application of Ca. Calcium application also resulted in up-regulation of the D1 protein. In conclusion, ability of calcium to reverse atrazine-induced oxidative damage and calcium regulatory role on GST in Pennisetum was presented. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Isolation of candidate genes for apomictic development in buffelgrass (Pennisetum ciliare).

    PubMed

    Singh, Manjit; Burson, Byron L; Finlayson, Scott A

    2007-08-01

    Asexual reproduction through seeds, or apomixis, is a process that holds much promise for agricultural advances. However, the molecular mechanisms underlying apomixis are currently poorly understood. To identify genes related to female gametophyte development in apomictic ovaries of buffelgrass (Pennisetum ciliare (L.) Link), Suppression Subtractive Hybridization of ovary cDNA with leaf cDNA was performed. Through macroarray screening of subtracted cDNAs two genes were identified, Pca21 and Pca24, that showed differential expression between apomictic and sexual ovaries. Sequence analysis showed that both Pca21 and Pca24 are novel genes not previously characterized in plants. Pca21 shows homology to two wheat genes that are also expressed during reproductive development. Pca24 has similarity to coiled-coil-helix-coiled-coil-helix (CHCH) domain containing proteins from maize and sugarcane. Northern blot analysis revealed that both of these genes are expressed throughout female gametophyte development in apomictic ovaries. In situ hybridizations localized the transcript of these two genes to the developing embryo sacs in the apomictic ovaries. Based on the expression patterns it was concluded that Pca21 and Pca24 likely play a role during apomictic development in buffelgrass.

  18. Second-generation ethanol production from elephant grass at high total solids.

    PubMed

    Menegol, Daiane; Fontana, Roselei Claudete; Dillon, Aldo José Pinheiro; Camassola, Marli

    2016-07-01

    The enzymatic hydrolysis of Pennisetum purpureum (elephant grass) was evaluated at high total solid levels (from 4% to 20% (w/v)) in a concomitant ball milling treatment in a rotating hydrolysis reactor (RHR). The greatest glucose yield was 20.17% when 4% (w/v) untreated biomass was employed. When sugars obtained from enzymatic hydrolysis were submitted to fermentation with Saccharomyces cerevisiae, the greatest ethanol yield was 22.61% when 4% (w/v) untreated biomass was employed; however, the highest glucose concentration (12.47g/L) was obtaining using 20% (w/v) solids and highest ethanol concentration (6.1g/L) was obtained using 16% (w/v) solids. When elephant grass was hydrolyzed in the rotating hydrolysis reactor, ethanol production was about double that was produced when the biomass was hydrolyzed in a static reactor (SR). These data indicate that it is possible to produce ethanol from elephant grass when milling treatment and enzymatic hydrolysis are performed at the same time. Copyright © 2016. Published by Elsevier Ltd.

  19. Invitro Study on the Fluid From Banana Stem Bioprocess as Direct Fed Microbial

    NASA Astrophysics Data System (ADS)

    Mutaqin, B. K.; Tanuwiria, U. H.; Hernawan, E.

    2018-02-01

    The purpose of this research was to study the liquid produced by the bioprocess of banana stem as a Direct Fed Microbial (DFM) in order to enhance local sheep productivity invitro. Studying was the use of DFM in two invitro feeds. The object observed in this research was fermentability and digestibility value. The method was experimental with the experimental design, i.e. factorial experimental design with two factors. The first factor was DFM, the levels of which were 0, 0,2, 0,4 and 0,6%, while the second factor was two feed types (complete feed and Pennisetum purpureum only) with the treatment of threefold repetition. This research showed that fermentability and digestibility value were influenced by the DFM in the invitro complete feed. The research result analyzed using MANOVA with further testing using Duncan Test. The conclusion of the research result were shows the interaction DFM in the complete feed improve fermentability and digestibility values and DFM 0,6% shows the highest value.

  20. Manninotriose is a major carbohydrate in red deadnettle (Lamium purpureum, Lamiaceae)

    PubMed Central

    dos Santos, Raquel; Vergauwen, Rudy; Pacolet, Pieter; Lescrinier, Eveline; Van den Ende, Wim

    2013-01-01

    Background and Aims There is a great need to search for natural compounds with superior prebiotic, antioxidant and immunostimulatory properties for use in (food) applications. Raffinose family oligosaccharides (RFOs) show such properties. Moreover, they contribute to stress tolerance in plants, acting as putative membrane stabilizers, antioxidants and signalling agents. Methods A large-scale soluble carbohydrate screening was performed within the plant kingdom. An unknown compound accumulated to a high extent in early-spring red deadnettle (Lamium purpureum) but not in other RFO plants. The compound was purified and its structure was unravelled with NMR. Organs and organ parts of red deadnettle were carefully dissected and analysed for soluble sugars. Phloem sap content was analysed by a common EDTA-based method. Key Results Early-spring red deadnettle stems and roots accumulate high concentrations of the reducing trisaccharide manninotriose (Galα1,6Galα1,6Glc), a derivative of the non-reducing RFO stachyose (Galα1,6Galα1,6Glcα1,2βFru). Detailed soluble carbohydrate analyses on dissected stem and leaf sections, together with phloem sap analyses, strongly suggest that stachyose is the main transport compound, but extensive hydrolysis of stachyose to manninotriose seems to occur along the transport path. Based on the specificities of the observed carbohydrate dynamics, the putative physiological roles of manninotriose in red deadnettle are discussed. Conclusions It is demonstrated for the first time that manninotriose is a novel and important player in the RFO metabolism of red dead deadnettle. It is proposed that manninotriose represents a temporary storage carbohydrate in early-spring deadnettle, at the same time perhaps functioning as a membrane protector and/or as an antioxidant in the vicinity of membranes, as recently suggested for other RFOs and fructans. This novel finding urges further research on this peculiar carbohydrate on a broader array of RFO

  1. Isolation, purification and characterization of antioxidative peptide of pearl millet (Pennisetum glaucum) protein hydrolysate.

    PubMed

    Agrawal, Himani; Joshi, Robin; Gupta, Mahesh

    2016-08-01

    Pearl millet (Pennisetum glaucum) is a rich source of protein, used for present study to hydrolyze protein, peptide separation and its functional activity. Antioxidative bioactive peptide was successfully identified from pearl millet using trypsin enzyme. Different antioxidative potential of isolated peptide were assessed based on activity of DPPH radical, ABTS radical, hydroxyl radical, Fe(2+) chelating ability and reducing power. Bioactive peptide separated by gel-filtration chromatography, showed the higher antioxidant activity as tested by different free radicals. The activity of pearl millet protein hydrolysate fraction was found for DPPH assay (67.66%), ABTS assay (78.81%), Fe(2+) chelating ability (51.20%), hydroxyl assay (60.95%) and reducing power (0.375nm) was further purified using reversed-phase UFLC and subjected to matrix assisted laser desorption/ionization time-of-flight/time-of-flight mass spectrometry (MALDI-TOF/TOF-MS) for sequential identification of the peptide. The sequence SDRDLLGPNNQYLPK was identified as antioxidant peptide. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Electrochemical behavior of the 316L steel type in a marine culture of microalgae (Porphyridium purpureum) under the 12/12 h photoperiod and effect of different working electrode exposure conditions on the biofilm-metal interface.

    PubMed

    Djemai-Zoghlache, Yamina; Isambert, Arsène; Belhaneche-Bensemra, Naima

    2011-12-01

    The industrial crops of microalgae use processes calling upon the presence of parts of metal nature such as steel 316L type. The goal of this study is to test the electrochemical behavior of this material in a marine culture of microalgae. Porphyridium purpureum was used under a photoperiod of alternation darkness/light 12/12 h, in order to apprehend the problems of biocorrosion involved in the biofouling. The evolution of the free potential of corrosion, according to the position of the samples and for different surface roughness, observations of the surface quality under the electron microscope with sweeping were carried out. The results showed that, overall, the strain P. purpureum does not have a corrosive effect on the 316L. The free potential of corrosion lies between -0.307 and -0.005 V(SCE). The adhesion of the cells seems stronger on the interface air/solid of the half-plunged sample with surface grit polished 1,000, confirmed by the presence of biofilm on the air part. The photoperiod acts on the evolution of the generated free potential of corrosion of the one 24-h period oscillation. Furthermore, the samples plunged horizontally lead to a stabilizing effect on the potential of free corrosion.

  3. Physicochemical characterization, modelling and optimization of ultrasono-assisted acid pretreatment of two Pennisetum sp. using Taguchi and artificial neural networking for enhanced delignification.

    PubMed

    Mohapatra, Sonali; Dandapat, Snigdha Jyotsna; Thatoi, Hrudayanath

    2017-02-01

    Acid as well as ultrasono-assisted acid pretreatment of lignocellulosic biomass of two Pennisetum sp.; Denanath grass (DG) and Hybrid Napier grass (HNG) have been investigated for enhanced delignification and maximum exposure of cellulose for production of bioethanol. Screening of pretreatment with different acids such as H 2 SO 4 , HCl, H 3 PO 4 and H 2 NO 3 were optimized for different temperature, soaking time and acid concentrations using Taguchi orthogonal array and the data obtained were statistically validated using artificial neural networking. HCl was found to be the most effective acid for pretreatment of both the Pennisetum sp. The optimized conditions of HCl pretreatment were acid concentration of 1% and 1.5%, soaking time 130 and 50 min and temperature 121 °C and 110 °C which yielded maximum delignification of 33.0% and 33.8% for DG and HNG respectively. Further ultrosono-assisted HCl pretreatment with a power supply of 100 W, temperature of 353 K, and duty cycle of 70% has resulted in significantly higher delignification of 80.4% and 82.1% for both DG and HNG respectively than that of acid pretreatment. Investigation using SEM, FTIR and autofloresence microscopy for both acid and ultrasono-assisted acid pretreatment lignocellulosic biomass revealed conformational changes of pretreated lignocellulosic biomass with decreased lignin content and increased exposure of cellulose, with greater effectiveness in case of ultrasono assisted acid pretreatment condition. Copyright © 2016. Published by Elsevier Ltd.

  4. Impact of bio-nanogold on seed germination and seedling growth in Pennisetum glaucum.

    PubMed

    Parveen, Asra; Mazhari, Bi Bi Zainab; Rao, Srinath

    2016-12-01

    Nanotechnology is leading towards the development of low cost applications to improve the cultivation and growth of plants. The use of nanotechnology in agriculture will leads to a significant effect on food industry along with opening a new area of research in agroecosystem. In this paper gold nanoparticles were biosynthesized with Cassia auriculata leaf extract at room temperature and characterized by UV-vis spectroscopy, X-ray diffraction and transmission electron microscopy. The objective of this study was to investigate effect of synthesized bio-nanogold on an important food and biofuel producing plant Pennisetum glaucum. Positive effects were observed on percentage of seed germination and growth of seedlings. Improved germination and increased plant biomass have high economic importance in production of biofuel or raw materials, agriculture and horticulture. Although the impact of nanoparticles on plants depends on concentration, size and shape. The biological synthesized AuNPs can replace the chemically synthesized AuNPs used in gene transfer method. The study gives brief insight on nanoparticles effects on plants, brings attention on both positive and negative side of nanomaterial which can resolve phytopathological infections by stimulating nutrition and growth. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. Prediction of genetic gains by selection indices using mixed models in elephant grass for energy purposes.

    PubMed

    Silva, V B; Daher, R F; Araújo, M S B; Souza, Y P; Cassaro, S; Menezes, B R S; Gravina, L M; Novo, A A C; Tardin, F D; Júnior, A T Amaral

    2017-09-27

    Genetically improved cultivars of elephant grass need to be adapted to different ecosystems with a faster growth speed and lower seasonality of biomass production over the year. This study aimed to use selection indices using mixed models (REML/BLUP) for selecting families and progenies within full-sib families of elephant grass (Pennisetum purpureum) for biomass production. One hundred and twenty full-sib progenies were assessed from 2014 to 2015 in a randomized block design with three replications. During this period, the traits dry matter production, the number of tillers, plant height, stem diameter, and neutral detergent fiber were assessed. Families 3 and 1 were the best classified, being the most indicated for selection effect. Progenies 40, 45, 46, and 49 got the first positions in the three indices assessed in the first cut. The gain for individual 40 was 161.76% using Mulamba and Mock index. The use of selection indices using mixed models is advantageous in elephant grass since they provide high gains with the selection, which are distributed among all the assessed traits in the most appropriate situation to breeding programs.

  6. Herbage intake, methane emissions and animal performance of steers grazing dwarf elephant grass v. dwarf elephant grass and peanut pastures.

    PubMed

    Andrade, E A; Almeida, E X; Raupp, G T; Miguel, M F; de Liz, D M; Carvalho, P C F; Bayer, C; Ribeiro-Filho, H M N

    2016-10-01

    Management strategies for increasing ruminant legume consumption and mitigating methane emissions from tropical livestock production systems require further study. The aim of this work was to evaluate the herbage intake, animal performance and enteric methane emissions of cattle grazing dwarf elephant grass (DEG) (Pennisetum purpureum cv. BRS Kurumi) alone or DEG with peanut (Arachis pintoi cv. Amarillo). The experimental treatments were the following: DEG pastures receiving nitrogen fertilization (150 kg N/ha as ammonium nitrate) and DEG intercropped with peanut plus an adjacent area of peanut that was accessible to grazing animals for 5 h/day (from 0700 to 1200 h). The animals grazing legume pastures showed greater average daily gain and herbage intake, and shorter morning and total grazing times. Daily methane emissions were greater from the animals grazing legume pastures, whereas methane emissions per unit of herbage intake did not differ between treatments. Allowing animals access to an exclusive area of legumes in a tropical grass-pasture-based system can improve animal performance without increasing methane production per kg of dry matter intake.

  7. Feeding of tropical trees and shrub foliages as a strategy to reduce ruminal methanogenesis: studies conducted in Cuba.

    PubMed

    Delgado, Denia Caridad; Galindo, Juana; González, Rogelio; González, Niurca; Scull, Idania; Dihigo, Luís; Cairo, Juan; Aldama, Ana Irma; Moreira, Onidia

    2012-06-01

    The aim of this paper was to present the main results obtained in Cuba on the effects of feeding tropical trees and shrubs on rumen methanogenesis in animals fed with low quality fibrous diets. More than 20 tree and shrub foliages were screened for phytochemicals and analyzed for chemical constituents. From these samples, seven promising plants (Samanea saman, Albizia lebbeck, Tithonia diversifolia, Leucaena leucocephala, Trichantera gigantea, Sapindus saponaria, and Morus alba) were evaluated for methane reduction using an in vitro rumen fermentation system. Results indicated that the inclusion levels of 25% of Sapindo, Morus, or Trichantera foliages in the foliages/grass mixtures (grass being Pennisetum purpureum) reduced (P < 0.01) methane production in vitro when compared to Pennisetum alone (17.0, 19.1, and 18.0 versus 26.2 mL CH(4)/g fermented dry matter, respectively). It was demonstrated that S. saman, A. lebbeck, or T. diversifolia accession 23 foliages when mixed at the rate of 30% in Cynodon nlemfuensis grass produced lower methane compared to the grass alone. Inclusion levels of 15% and 25% of a ruminal activator supplement containing 29% of L. leucocehala foliage meal reduced methane by 37% and 42% when compared to the treatment without supplementation. In vivo experiment with sheep showed that inclusion of 27% of L. leucocephala in the diet increased the DM intake but did not show significant difference in methane production compared to control diet without this foliage. The results of these experiments suggest that the feeding of tropical tree and shrub foliages could be an attractive strategy for reduction of ruminal methanogenesis from animals fed with low-quality forage diets and for improving their productivity.

  8. Comparative gene expression in sexual and apomictic ovaries of Pennisetum ciliare (L.) Link.

    PubMed

    Vielle-Calzada, J P; Nuccio, M L; Budiman, M A; Thomas, T L; Burson, B L; Hussey, M A; Wing, R A

    1996-12-01

    Limited emphasis has been given to the molecular study of apomixis, an asexual method of reproduction where seeds are produced without fertilization. Most buffelgrass (Pennisetum ciliare (L.) Link syn = Cenchrus ciliaris L.) genotypes reproduce by obligate apomixis (apospory); however, rare sexual plants have been recovered. A modified differential display procedure was used to compare gene expression in unpollinated ovaries containing ovules with either sexual or apomictic female gametophytes. The modification incorporated end-labeled poly(A)+ anchored primers as the only isotopic source, and was a reliable and consistent approach for detecting differentially displayed transcripts. Using 20 different decamers and two anchor primers, 2268 cDNA fragments between 200 and 600 bp were displayed. From these, eight reproducible differentially displayed cDNAs were identified and cloned. Based on northern analysis, one cDNA was detected in only the sexual ovaries, two cDNAs in only apomictic ovaries and one cDNA was present in both types of ovaries. Three fragments could not be detected and one fragment was detected in ovaries, stems, and leaves. Comparison of gene expression during sexual and apomictic development in buffelgrass represents a new model system and a strategy for investigating female reproductive development in the angiosperms.

  9. Exploring surface characterization and electrostatic property of Hybrid Pennisetum during alkaline sulfite pretreatment for enhanced enzymatic hydrolysability.

    PubMed

    Yang, Ming; Wang, Jingfeng; Hou, Xincun; Wu, Juying; Fan, Xifeng; Jiang, Fan; Tao, Pan; Wang, Fan; Peng, Pai; Yang, Fangxia; Zhang, Junhua

    2017-11-01

    The surface characterization and electrostatic property of Hybrid Pennisetum (HP) after alkaline sulfite pretreatment were explored for enhanced enzymatic hydrolysability. The O/C ratio in HP increased from 0.34 to 0.60, and C1 concentration decreased from 62.5% to 31.6%, indicating that alkaline sulfite pretreatment caused poorer lignin but richer carbohydrate on HP surface. Zeta potential and sulfur element analysis indicated that more enzymes would preferably adsorb on the carbohydrate surface of alkaline sulfite pretreated HP because the lignin was sulfonated, which facilitated the decrease of non-productive adsorption. Glucose yield of alkaline sulfite pretreated HP reached to 100% by synergistic action of cellulase and xylanase in the hydrolysis, which was significantly higher than that of NaOH pretreated, and the concentration of glucose released was 1.52times higher. The results suggested that alkaline sulfite pretreatment had potential for improving the HP hydrolysability, and the surface characterization and electrostatic property facilitated the enzymatic digestibility. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. UPLC-MSE Profiling of Phytoplankton Metabolites: Application to the Identification of Pigments and Structural Analysis of Metabolites in Porphyridium purpureum

    PubMed Central

    Juin, Camille; Bonnet, Antoine; Nicolau, Elodie; Bérard, Jean-Baptiste; Devillers, Romain; Thiéry, Valérie; Cadoret, Jean-Paul; Picot, Laurent

    2015-01-01

    A fast and high-resolution UPLC-MSE analysis was used to identify phytoplankton pigments in an ethanol extract of Porphyridium purpureum (Pp) devoid of phycobiliproteins. In a first step, 22 standard pigments were analyzed by UPLC-MSE to build a database including retention time and accurate masses of parent and fragment ions. Using this database, seven pigments or derivatives previously reported in Pp were unequivocally identified: β,β-carotene, chlorophyll a, zeaxanthin, chlorophyllide a, pheophorbide a, pheophytin a, and cryptoxanthin. Minor amounts of Divinyl chlorophyll a, a chemotaxonomic pigment marker for prochlorophytes, were also unequivocally identified using the database. Additional analysis of ionization and fragmentation patterns indicated the presence of ions that could correspond to hydroxylated derivatives of chlorophyll a and pheophytin a, produced during the ethanolic extraction, as well as previously described galactosyldiacylglycerols, the thylakoid coenzyme plastoquinone, and gracilamide B, a molecule previously reported in the red seaweed Gracillaria asiatica. These data point to UPLC-MSE as an efficient technique to identify phytoplankton pigments for which standards are available, and demonstrate its major interest as a complementary method for the structural elucidation of ionizable marine molecules. PMID:25913708

  11. Prospection and Evaluation of (Hemi) Cellulolytic Enzymes Using Untreated and Pretreated Biomasses in Two Argentinean Native Termites

    PubMed Central

    Ben Guerrero, Emiliano; Arneodo, Joel; Bombarda Campanha, Raquel; Abrão de Oliveira, Patrícia; Veneziano Labate, Mônica T.; Regiani Cataldi, Thaís; Campos, Eleonora; Cataldi, Angel; Labate, Carlos A.; Martins Rodrigues, Clenilson; Talia, Paola

    2015-01-01

    Saccharum officinarum bagasse (common name: sugarcane bagasse) and Pennisetum purpureum (also known as Napier grass) are among the most promising feedstocks for bioethanol production in Argentina and Brazil. In this study, both biomasses were assessed before and after acid pretreatment and following hydrolysis with Nasutitermes aquilinus and Cortaritermes fulviceps termite gut digestome. The chemical composition analysis of the biomasses after diluted acid pretreatment showed that the hemicellulose fraction was partially removed. The (hemi) cellulolytic activities were evaluated in bacterial culture supernatants of termite gut homogenates grown in treated and untreated biomasses. In all cases, we detected significantly higher endoglucanase and xylanase activities using pretreated biomasses compared to untreated biomasses, carboxymethylcellulose and xylan. Several protein bands with (hemi) cellulolytic activity were detected in zymograms and two-dimensional gel electrophoresis. Some proteins of these bands or spots were identified as xylanolytic peptides by mass spectrometry. Finally, the diversity of cultured cellulolytic bacterial endosymbionts associated to both Argentinean native termite species was analyzed. This study describes, for the first time, bacterial endosymbionts and endogenous (hemi) cellulases of two Argentinean native termites as well as their potential application in degradation of lignocellulosic biomass for bioethanol production. PMID:26313257

  12. Capability of Thai Mission grass (Pennisetum polystachyon) as a new weedy lignocellulosic feedstock for production of monomeric sugar.

    PubMed

    Tatijarern, Patomwat; Prasertwasu, Sirirat; Komalwanich, Tidarat; Chaisuwan, Thanyalak; Luengnaruemitchai, Apanee; Wongkasemjit, Sujitra

    2013-09-01

    Mission grass (Pennisetum polystachyon) grown in Pakchong District, Nakornratchasima Province, Thailand, with high cellulose and hemicellulose contents were harvested to determine the fermentable monomeric sugars for bioethanol production by two-stage microwave/chemical pretreatment process. Microwave-assisted NaOH pretreatment effectively removed approximately 85% lignin content in Mission grass, using 3% (w/v) NaOH, 15:1 liquid-to-solid ratio (LSR) at 120 °C temperatures for 10 min. As a result, in the second stage, microwave-assisted H2SO4 pretreatment of an alkaline-pretreated Mission grass solid releasedan impressively high fermentable sugar content (34.3±1.3 g per 100 g of dried biomass), consisting mainly of 31.1±0.8 g of glucose per 100 g of dried biomass, using 1% (w/v) H2SO4, 15:1 LSR at 200 °C temperature for a very short pretreatment time (5 min). The total monomeric sugar yield obtained via two-stage microwave/chemical process was 40.9 g per 100 g of dried biomass. Copyright © 2013 Elsevier Ltd. All rights reserved.

  13. Seedling growth of a native (Ampelodesmos mauritanicus) and an exotic (Pennisetum setaceum) grass

    NASA Astrophysics Data System (ADS)

    Badalamenti, Emilio; Militello, Marcello; La Mantia, Tommaso; Gugliuzza, Giovanni

    2016-11-01

    Scarce information is available on the biological reasons why a small subset of introduced species can effectively establish within novel ecosystems. A comparison of early growth traits can help to explain the better performance of alien invasive species versus native co-occurring species. In one year-long experiment, we compared the early life stages of Ampelodesmos mauritanicus (Poir.) Dur. & Schinz (Amp), a native perennial Mediterranean grass, and Pennisetum setaceum (Forssk.) Chiov (Penn), an emerging invader grass in sub-arid and Mediterranean-climate areas. The Penn seedlings grew significantly faster and were approximately 2.5 times taller than the Amp seedlings, reaching a final average height of 90 cm. The shoot and root dry masses of the Penn seedlings were, respectively, more than 14 times and 4 times higher than those of the Amp seedlings. As a consequence, the shoot:root ratio was significantly higher in Penn, which resulted in a greater allocation of resources to the photosynthetic organs. Penn showed a more rapid life cycle compared with Amp. Penn produced seeds 9 months after sowing while no spikelet was produced by Amp until the end of the experiment. As a consequence, Penn may gain a reproductive advantage due to rapid seed dissemination. Ultimately, a suite of peculiar early growth traits makes Penn an aggressive competitor against Amp, which is an important floristic element of native Mediterranean grasslands. Penn seems better suited than Amp in colonizing frequently disturbed sites with fluctuating resource availability or irregular rainfall distribution and Penn is gradually replacing Amp.

  14. Constancy of local spread rates for buffelgrass (Pennisetum ciliare L.) in the Arizona Upland of the Sonoran Desert

    USGS Publications Warehouse

    Olsson, Aaryn D.; Betancourt, Julio L.; Crimmins, Michael A.; Marsh, Stuart E.

    2012-01-01

    In North American deserts, grass invasions threaten native vegetation via competition and altered fire regimes. Accurate prediction and successful mitigation of these invasions hinge on estimation of spread rates and their degree of constancy in time and space. We used high-resolution aerial photographs from 11 sites in the Santa Catalina Mountains, southern Arizona to reconstruct the spread of buffelgrass (Pennisetum ciliare), a C4 perennial bunchgrass, since 1980. The total area infested was fit to a logistic model and residuals of the model were compared to climatic factors of the corresponding and lagged time periods. Infestations grew from small colonizing patches in the 1980s to 66 ha in 2008, doubling every 2.26–7.04 years since 1988. Although buffelgrass germination, establishment and distribution are favored by wet summers and warm winters, climate variables did not predict spread rates. Buffelgrass has grown at a constant rate, at least since 1988, when much of its expansion took place. In the study area, minimum requirements are met almost every year for germination and reproduction, establishing a consistent baseline for spread that manifests as a constant spread rate.

  15. Abattoir Wastewater Irrigation Increases the Availability of Nutrients and Influences on Plant Growth and Development.

    PubMed

    Matheyarasu, Raghupathi; Bolan, Nanthi S; Naidu, Ravi

    This study evaluated the effects of abattoir wastewater irrigation on plant growth and development. The soils used in this study were collected from Primo Smallgoods Abattoir (Port Wakefield, South Australia) at different sites such as currently irrigated (CI), currently not irrigated (CNI) and soil outside the irrigation area as control (CTRL). A completely randomised block design was employed for the plant growth experiment, where four crops (Pennisetum purpureum , Medicago sativa , Sinapis alba and Helianthus annuus ) were grown separately on three different soils (CI, CNI and CTRL) in plastic pots. Two types of water (tap water and wastewater) and two loadings were applied throughout the planting period based on the field capacity (FC 100 and 150 %). The overall dry matter yield was compared between the soils and treatments. Under wastewater irrigation, among the four species grown in the CI soil, P. purpureum (171 g) and H. annuus (151 g) showed high biomass yields, followed by S. alba (115 g) and M. sativa (31 g). The plants grown under tap water showed about 70 % lower yields compared to the abattoir wastewater irrigation (AWW). Similar trends in the biomass yields were observed for CNI and CTRL soils under the two water treatments, with the biomass yields in the following order CI > CNI > CTRL soils. The results confirm the beneficial effects of AWW at the greenhouse level. However, a proper cropping pattern and wastewater irrigation management plan is essential to utilise the nutrients available in the wastewater-irrigated land treatment sites. The increase in fertility is evident from the effects of wastewater on biomass growth and also the abundance of nutrients accumulated in plants. A mass balance calculation on the applied, residual and the plant-accumulated nutrients over a few cropping periods will help us in understanding the nutrient cycling processes involved in the abattoir-irrigated land treatment sites, which will serve as an effective

  16. Reproductive Response of Ewes Fed with Taiwan Grass Hay (Pennisetum purpureum Schum.) Supplemented with Duckweed (Lemna sp. and Spirodela sp.)

    PubMed Central

    Zetina-Córdoba, P.; Ortega-Cerrilla, M. E.; Sánchez Torres-Esqueda, M. T.; Herrera-Haro, J. G.; Ortega-Jiménez, E.; Reta-Mendiola, J. L.; Vilaboa-Arroniz, J.

    2012-01-01

    The effect of duckweed (DW) supplementation was evaluated on dry matter intake (DMI), presence and duration of estrus, percentage of ewes repeating estrus and pregnancy rate, as well as the concentration of progesterone (P4) in multiparous crossbred ewes from Pelibuey, Dorper, and Katahdin breeds, fed with Taiwan grass hay (TWH). Eighteen ewes with 39.7±4 kg mean body weight, kept in individual pens, were randomly assigned to one of the following treatments: T1: TWH, T2: TWH plus 200 g DW, T3: TWH plus 300 g DW. The ewes were synchronized with 40 mg fluorogestone acetate (FGA) and 400 UI equine chorionic gonadotropin (eCG). Data were analyzed as a completely randomized design using the GLM procedure. DW supplementation had no effect on dry matter intake (p>0.05); however, a slight decrease of TWH intake was observed as DW supplementation increased. No differences (p>0.05) were found in the beginning of estrus, percentage of ewes presenting it, its duration, or pregnancy rate. There were no differences (p>0.05) on P4 concentration among treatments, or treatmentxperiod interaction (p>0.05). However the period was significant (p<0.01), since the P4 levels increased as time increased after the removal of the FGA device and eCG application. PMID:25049670

  17. Effect of domestic processing on the polyphenol content and bioaccessibility in finger millet (Eleusine coracana) and pearl millet (Pennisetum glaucum).

    PubMed

    Hithamani, Gavirangappa; Srinivasan, Krishnapura

    2014-12-01

    Finger millet (Eleusine coracana) and pearl millet (Pennisetum glaucum) were evaluated for polyphenolic content and their bioaccessibility. Total polyphenols of native finger millet was 10.2mg/g which reduced by 50% after sprouting or pressure-cooking, while 12-19% reduction was seen after open-pan boiling. Total flavonoids of the grain reduced drastically on sprouting, pressure-cooking or open-pan boiling. Concentration of phenolic acids generally increased during sprouting and roasting of finger millet. Pressure cooking, open-pan boiling and microwave-heating reduced the bioaccessible polyphenols by 30-35%, while the same was increased by 67% by sprouting. Significant reduction of total polyphenols was observed in pressure-cooked, open-pan boiled and microwave-heated pearl millet. Concentration of sinapic and salicylic acids were highest phenolic acids of pearl millet. Total polyphenols reduced during sprouting and pressure-cooking. There was a 20% increase in the bioaccessible polyphenols after sprouting of pearl millet. Thus, sprouting and roasting provided more bioaccessible phenolics from these two common millets studied. Copyright © 2014. Published by Elsevier Ltd.

  18. Steers performance in dwarf elephant grass pastures alone or mixed with Arachis pintoi.

    PubMed

    Crestani, Steben; Ribeiro Filho, Henrique Mendonça Nunes; Miguel, Marcolino Frederico; de Almeida, Edison Xavier; Santos, Flávio Augusto Portela

    2013-08-01

    The inclusion of legumes in pasture reduces the need for mineral nitrogen applications and the pollution of groundwater; however, the agronomic and animal husbandry advantages with tropical legumes are still little known. The objective of this study was to quantify the effect of the use of forage peanut (Arachis pintoi cv. Amarillo) in dwarf elephant grass pastures (Pennisetum purpureum cv. BRS Kurumi) on forage intake and animal performance. The experimental treatments were dwarf elephant grass fertilized with 200 kg N/ha, and dwarf elephant grass mixed with forage peanut without mineral fertilizers. The animals used for the experiment were 12 Charolais steers (body weight (BW) = 288 ± 5.2 kg) divided into four lots (two per treatment). Pastures were managed under intermittent stocking with an herbage allowance of 5.4 kg dry matter of green leaves/100 kg BW. Dry matter intake (mean = 2.44% BW), the average daily gain (mean = 0.76 kg), and the stocking rate (mean = 3.8 AU/ha) were similar between the studied pastures, but decreased drastically in last grazing cycle with the same herbage allowance. The presence of peanut in dwarf elephant grass pastures was enough to sustain the stocking rate, but did not allow increasing forage intake and animal performance.

  19. Fatty acid profile in vertical strata of elephant grass subjected to intermittent stocking.

    PubMed

    Dias, Kamila M; Schmitt, Daniel; Rodolfo, Giselle R; Deschamps, Francisco C; Camargo, Guilherme N; Pereira, Raphael S; Sbrissia, André F

    2017-01-01

    The milk and meat from animals with a pasture-based diet have higher proportions of CLA and C18:3 and lower omega-6:omega-3 ratios than products from animals with diets based on corn silage and concentrate. However, most of the published studies have evaluated fatty acid profiles in temperate climate grasses and the literature with tropical grasses is scarce. Thus, the aim of this study was to evaluate the morphological and fatty acid compositions in the vertical strata of elephant grass (Pennisetum purpureum Schum.) swards subjected to grazing heights (90 or 120 cm pre-grazing heights) and levels of defoliation (50% or 70% removal of the initial pre-grazing height). There were no interactions among pre-grazing height, the level of defoliation and grazing stratum. However, higher proportion of C18:3 (58% and 63%) was found in the 90-cm swards and in the half upper stratum. A higher proportion of C18:3 was associated with a higher leaf proportion and crude protein content. Thus, the upper stratum of sward or a grazing management scheme (e.g. first-last stocking) resulting in a higher proportion of leaves and crude protein both provide higher proportions of C18:3 to animals grazing in elephant grass swards.

  20. Genetic Diversity of Namibian Pennisetum glaucum (L.) R. BR. (Pearl Millet) Landraces Analyzed by SSR and Morphological Markers.

    PubMed

    McBenedict, Billy; Chimwamurombe, Percy; Kwembeya, Ezekeil; Maggs-Kölling, Gillian

    2016-01-01

    Current Pennisetum glaucum (L.) R. BR. cultivars in Namibia have overall poor performance posing a threat to the nation's food security because this crop is staple for over 70% of the Namibian population. The crop suffers from undesirable production traits such as susceptibility to diseases, low yield, and prolonged reproductive cycle. This study aimed to understand the genetic diversity of the crop in Namibia by simple sequence repeats (SSRs) and morphology analysis. A total of 1441 genotypes were collected from the National Gene Bank representing all the Namibian landraces. A sample of 96 genotypes was further analyzed by SSR using Shannon-Wiener diversity index and revealed a value of 0.45 indicating low genetic diversity. Ordination using Principal Coordinate Analysis (PCoA) on SSR data confirmed clusters generated by UPGMA for the 96 P. glaucum accessions. UPGMA phenograms of 29 morphological characterized genotypes were generated for SSR and morphology data and the two trees revealed 78% resemblance. Lodging susceptibility, tillering attitude, spike density, fodder yield potential, early vigour, and spike shape were the phenotypic characters upon which some clusters were based in both datasets. It is recommended that efforts should be made to widen the current gene pool in Namibia.

  1. Genetic Diversity of Namibian Pennisetum glaucum (L.) R. BR. (Pearl Millet) Landraces Analyzed by SSR and Morphological Markers

    PubMed Central

    McBenedict, Billy; Chimwamurombe, Percy; Kwembeya, Ezekeil; Maggs-Kölling, Gillian

    2016-01-01

    Current Pennisetum glaucum (L.) R. BR. cultivars in Namibia have overall poor performance posing a threat to the nation's food security because this crop is staple for over 70% of the Namibian population. The crop suffers from undesirable production traits such as susceptibility to diseases, low yield, and prolonged reproductive cycle. This study aimed to understand the genetic diversity of the crop in Namibia by simple sequence repeats (SSRs) and morphology analysis. A total of 1441 genotypes were collected from the National Gene Bank representing all the Namibian landraces. A sample of 96 genotypes was further analyzed by SSR using Shannon-Wiener diversity index and revealed a value of 0.45 indicating low genetic diversity. Ordination using Principal Coordinate Analysis (PCoA) on SSR data confirmed clusters generated by UPGMA for the 96 P. glaucum accessions. UPGMA phenograms of 29 morphological characterized genotypes were generated for SSR and morphology data and the two trees revealed 78% resemblance. Lodging susceptibility, tillering attitude, spike density, fodder yield potential, early vigour, and spike shape were the phenotypic characters upon which some clusters were based in both datasets. It is recommended that efforts should be made to widen the current gene pool in Namibia. PMID:27433479

  2. Changes in soil bacterial communities induced by the invasive plant Pennisetum setaceum in a semiarid environment

    NASA Astrophysics Data System (ADS)

    Rodriguez-Caballero, Gema; Caravaca, Fuensanta; del Mar Alguacil, María; Fernández-López, Manuel; José Fernández-González, Antonio; García-Orenes, Fuensanta; Roldán, Antonio

    2016-04-01

    Invasive alien species are considered as a global threat being among the main causes of biodiversity loss. Plant invasions have been extensively studied from different disciplines with the purpose of identifying predictor traits of invasiveness and finding solutions. However, less is known about the implication of the rhizosphere microbiota in these processes, even when it is well known the importance of the interaction between plant rhizosphere and microbial communities. The objective of this study was to determine whether native and invasive plants support different bacterial communities in their rhizospheres and whether there are bacterial indicator species that might be contributing to the invasion process of these ecosystems. We carried out a study in five independent locations under Mediterranean semiarid conditions, where the native Hyparrhenia hirta is being displaced by Pennisetum setaceum, an aggressive invasive Poaceae and soil bacterial communities were amplified and 454-pyrosequenced. Changes in the composition and structure of the bacterial communities, owing to the invasive status of the plant, were detected when the richness and alpha-diversity estimators were calculated as well as when we analyzed the PCoA axes scores. The Indicator Species Analysis results showed a higher number of indicators for invaded communities at all studied taxonomic levels. In conclusion, the effect of the invasiveness and its interaction with the soil location has promoted shifts in the rhizosphere bacterial communities which might be facilitating the invader success in these ecosystems.

  3. Supplementation with Ca salts of soybean oil interacts with concentrate level in grazing dairy cows: intake, ingestive behavior, and ruminal parameters.

    PubMed

    Macedo, Fernanda Lopes; Batistel, Fernanda; de Souza, Jonas; Chagas, Lucas Jado; Santos, Flávio Augusto Portela

    2016-12-01

    In this study, we investigated the associative effects of concentrate levels and Ca salts of soybean oil (CSSO) supplementation on performance and ruminal parameters of mid-lactation dairy cows grazing on tropical pasture. Twenty-four Jersey × Holstein cows were used in a randomized block design and assigned to four treatments arranged in a 2 × 2 factorial design. Factors evaluated were concentrate levels (low, 3 kg/day vs. high, 7 kg/day of concentrate) and CSSO supplementation (without CSSO vs. with 250 g CSSO cow/day). All cows grazed on elephant grass (Pennisetum purpureum cv. Cameroon) and received the supplemental treatments for a 90-day period. The high concentrate level decreased forage intake and grazing time. In addition, the high concentrate level increased rumen propionate concentration and microbial synthesis and tended to decrease ammonia-N compared with low concentrate level. The addition of CSSO tended to decrease valerate, isobutyrate, isovalerate, and microbial synthesis. In conclusion, feeding CSSO for mid lactating cows grazing on tropical pasture had negative effects on rumen function. In contrast, CSSO supplementation tended to interact with concentrate level and increased energy intake when fed at low concentrate level. Feeding the high level of concentrate was an effective strategy to increase energy intake and microbial synthesis and improve N utilization.

  4. A novel approach for monitoring genetically engineered microorganisms by using artificial, stable RNAs

    NASA Technical Reports Server (NTRS)

    Pitulle, C.; Hedenstierna, K. O.; Fox, G. E.

    1995-01-01

    Further improvements in technology for efficient monitoring of genetically engineered microorganisms (GEMs) in the environment are needed. Technology for monitoring rRNA is well established but has not generally been applicable to GEMs because of the lack of unique rRNA target sequences. In the work described herein, it is demonstrated that a deletion mutant of a plasmid-borne Vibrio proteolyticus 5S rRNA gene continues to accumulate to high levels in Escherichia coli although it is no longer incorporated into 70S ribosomes. This deletion construct was subsequently modified by mutagenesis to create a unique recognition site for the restriction endonuclease BstEII, into which new sequences could be readily inserted. Finally, a novel 17-nucleotide identifier sequence from Pennisetum purpureum was embedded into the construct to create an RNA identification cassette. The artificial identifier RNA, expressed from this cassette in vivo, accumulated in E. coli to levels comparable to those of wild-type 5S rRNA without being seriously detrimental to cell survival in laboratory experiments and without entering the ribosomes. These results demonstrate that artificial, stable RNAs containing sequence segments remarkably different from those present in any known rRNA can be designed and that neither the deleted sequence segment nor ribosome incorporation is essential for accumulation of an RNA product.

  5. Segmental allotetraploidy and allelic interactions in buffelgrass (Pennisetum ciliare (L.) Link syn. Cenchrus ciliaris L.) as revealed by genome mapping.

    PubMed

    Jessup, R W; Burson, B L; Burow, O; Wang, Y W; Chang, C; Li, Z; Paterson, A H; Hussey, M A

    2003-04-01

    Linkage analyses increasingly complement cytological and traditional plant breeding techniques by providing valuable information regarding genome organization and transmission genetics of complex polyploid species. This study reports a genome map of buffelgrass (Pennisetum ciliare (L.) Link syn. Cenchrus ciliaris L.). Maternal and paternal maps were constructed with restriction fragment length polymorphisms (RFLPs) segregating in 87 F1 progeny from an intraspecific cross between two heterozygous genotypes. A survey of 862 heterologous cDNAs and gDNAs from across the Poaceae, as well as 443 buffelgrass cDNAs, yielded 100 and 360 polymorphic probes, respectively. The maternal map included 322 RFLPs, 47 linkage groups, and 3464 cM, whereas the paternal map contained 245 RFLPs, 42 linkage groups, and 2757 cM. Approximately 70 to 80% of the buffelgrass genome was covered, and the average marker spacing was 10.8 and 11.3 cM on the respective maps. Preferential pairing was indicated between many linkage groups, which supports cytological reports that buffelgrass is a segmental allotetraploid. More preferential pairing (disomy) was found in the maternal than paternal parent across linkage groups (55 vs. 38%) and loci (48 vs. 15%). Comparison of interval lengths in 15 allelic bridges indicated significantly less meiotic recombination in paternal gametes. Allelic interactions were detected in four regions of the maternal map and were absent in the paternal map.

  6. Preferential recruitment of the maternal centromere-specific histone H3 (CENH3) in oat (Avena sativa L.) × pearl millet (Pennisetum glaucum L.) hybrid embryos.

    PubMed

    Ishii, Takayoshi; Sunamura, Naohiro; Matsumoto, Ayaka; Eltayeb, Amin Elsadig; Tsujimoto, Hisashi

    2015-12-01

    Chromosome elimination occurs frequently in interspecific hybrids between distantly related species in Poaceae. However, chromosomes from both parents behave stably in a hybrid of female oat (Avena sativa L.) pollinated by pearl millet (Pennisetum glaucum L.). To analyze the chromosome behavior in this hybrid, we cloned the centromere-specific histone H3 (CENH3) genes of oat and pearl millet and produced a pearl millet-specific anti-CENH3 antibody. Application of this antibody together with a grass species common anti-CENH3 antibody revealed the dynamic CENH3 composition of the hybrid cells before and after fertilization. Despite co-expression of CENH3 genes encoded by oat and pearl millet, only an oat-type CENH3 was incorporated into the centromeres of both species in the hybrid embryo. Oat CENH3 enables a functional centromere in pearl millet chromosomes in an oat genetic background. Comparison of CENH3 genes among Poaceae species that show chromosome elimination in interspecific hybrids revealed that the loop 1 regions of oat and pearl millet CENH3 exhibit exceptionally high similarity.

  7. Soil, vegetation, and seed bank of a Sonoran Desert ecosystem along an exotic plant (Pennisetum ciliare) treatment gradient.

    PubMed

    Abella, Scott R; Chiquoine, Lindsay P; Backer, Dana M

    2013-10-01

    Ecological conditions following removal of exotic plants are a key part of comprehensive environmental management strategies to combat exotic plant invasions. We examined ecological conditions following removal of the management-priority buffelgrass (Pennisetum ciliare) in Saguaro National Park of the North American Sonoran Desert. We assessed soil, vegetation, and soil seed banks on seven buffelgrass site types: five different frequencies of buffelgrass herbicide plus hand removal treatments (ranging from 5 years of annual treatment to a single year of treatment), untreated sites, and non-invaded sites, with three replicates for each of the seven site types. The 22 measured soil properties (e.g., pH) differed little among sites. Regarding vegetation, buffelgrass cover was low (≤1% median cover), or absent, across all treated sites but was high (10-70%) in untreated sites. Native vegetation cover, diversity, and composition were indistinguishable across site types. Species composition was dominated by native species (>93% relative cover) across all sites except untreated buffelgrass sites. Most (38 species, 93%) of the 41 species detected in soil seed banks were native, and native seed density did not differ significantly across sites. Results suggest that: (1) buffelgrass cover was minimal across treated sites; (2) aside from high buffelgrass cover in untreated sites, ecological conditions were largely indistinguishable across sites; (3) soil seed banks harbored ≥12 species that were frequent in the aboveground vegetation; and (4) native species dominated post-treatment vegetation composition, and removing buffelgrass did not result in replacement by other exotic species.

  8. Comparative Physical Mapping of the Apospory-Specific Genomic Region in Two Apomictic Grasses: Pennisetum squamulatum and Cenchrus ciliaris

    PubMed Central

    Goel, Shailendra; Chen, Zhenbang; Akiyama, Yukio; Conner, Joann A.; Basu, Manojit; Gualtieri, Gustavo; Hanna, Wayne W.; Ozias-Akins, Peggy

    2006-01-01

    In gametophytic apomicts of the aposporous type, each cell of the embryo sac is genetically identical to somatic cells of the ovule because they are products of mitosis, not of meiosis. The egg of the aposporous embryo sac follows parthenogenetic development into an embryo; therefore, uniform progeny result even from heterozygous plants, a trait that would be valuable for many crop species. Attempts to introgress apomixis from wild relatives into major crops through traditional breeding have been hindered by low or no recombination within the chromosomal region governing this trait (the apospory-specific genomic region or ASGR). The lack of recombination also has been a major obstacle to positional cloning of key genes. To further delineate and characterize the nonrecombinant ASGR, we have identified eight new ASGR-linked, AFLP-based molecular markers, only one of which showed recombination with the trait for aposporous embryo sac development. Bacterial artificial chromosome (BAC) clones identified with the ASGR-linked AFLPs or previously mapped markers, when mapped by fluorescence in situ hybridization in Pennisetum squamulatum and Cenchrus ciliaris, showed almost complete macrosynteny between the two apomictic grasses throughout the ASGR, although with an inverted order. A BAC identified with the recombinant AFLP marker mapped most proximal to the centromere of the ASGR-carrier chromosome in P. squamulatum but was not located on the ASGR-carrier chromosome in C. ciliaris. Exceptional regions where synteny was disrupted probably are nonessential for expression of the aposporous trait. The ASGR appears to be maintained as a haplotype even though its position in the genome can be variable. PMID:16547108

  9. Soil, Vegetation, and Seed Bank of a Sonoran Desert Ecosystem Along an Exotic Plant ( Pennisetum ciliare) Treatment Gradient

    NASA Astrophysics Data System (ADS)

    Abella, Scott R.; Chiquoine, Lindsay P.; Backer, Dana M.

    2013-10-01

    Ecological conditions following removal of exotic plants are a key part of comprehensive environmental management strategies to combat exotic plant invasions. We examined ecological conditions following removal of the management-priority buffelgrass ( Pennisetum ciliare) in Saguaro National Park of the North American Sonoran Desert. We assessed soil, vegetation, and soil seed banks on seven buffelgrass site types: five different frequencies of buffelgrass herbicide plus hand removal treatments (ranging from 5 years of annual treatment to a single year of treatment), untreated sites, and non-invaded sites, with three replicates for each of the seven site types. The 22 measured soil properties (e.g., pH) differed little among sites. Regarding vegetation, buffelgrass cover was low (≤1 % median cover), or absent, across all treated sites but was high (10-70 %) in untreated sites. Native vegetation cover, diversity, and composition were indistinguishable across site types. Species composition was dominated by native species (>93 % relative cover) across all sites except untreated buffelgrass sites. Most (38 species, 93 %) of the 41 species detected in soil seed banks were native, and native seed density did not differ significantly across sites. Results suggest that: (1) buffelgrass cover was minimal across treated sites; (2) aside from high buffelgrass cover in untreated sites, ecological conditions were largely indistinguishable across sites; (3) soil seed banks harbored ≥12 species that were frequent in the aboveground vegetation; and (4) native species dominated post-treatment vegetation composition, and removing buffelgrass did not result in replacement by other exotic species.

  10. Field-Based Estimates of Global Warming Potential in Bioenergy Systems of Hawaii: Crop Choice and Deficit Irrigation.

    PubMed

    Pawlowski, Meghan N; Crow, Susan E; Meki, Manyowa N; Kiniry, James R; Taylor, Andrew D; Ogoshi, Richard; Youkhana, Adel; Nakahata, Mae

    2017-01-01

    Replacing fossil fuel with biofuel is environmentally viable from a climate change perspective only if the net greenhouse gas (GHG) footprint of the system is reduced. The effects of replacing annual arable crops with perennial bioenergy feedstocks on net GHG production and soil carbon (C) stock are critical to the system-level balance. Here, we compared GHG flux, crop yield, root biomass, and soil C stock under two potential tropical, perennial grass biofuel feedstocks: conventional sugarcane and ratoon-harvested, zero-tillage napiergrass. Evaluations were conducted at two irrigation levels, 100% of plantation application and at a 50% deficit. Peaks and troughs of GHG emission followed agronomic events such as ratoon harvest of napiergrass and fertilization. Yet, net GHG flux was dominated by carbon dioxide (CO2), as methane was oxidized and nitrous oxide (N2O) emission was very low even following fertilization. High N2O fluxes that frequently negate other greenhouse gas benefits that come from replacing fossil fuels with agronomic forms of bioenergy were mitigated by efficient water and fertilizer management, including direct injection of fertilizer into buried irrigation lines. From soil intensively cultivated for a century in sugarcane, soil C stock and root biomass increased rapidly following cultivation in grasses selected for robust root systems and drought tolerance. The net soil C increase over the two-year crop cycle was three-fold greater than the annualized soil surface CO2 flux. Deficit irrigation reduced yield, but increased soil C accumulation as proportionately more photosynthetic resources were allocated belowground. In the first two years of cultivation napiergrass did not increase net greenhouse warming potential (GWP) compared to sugarcane, and has the advantage of multiple ratoon harvests per year and less negative effects of deficit irrigation to yield.

  11. Field-Based Estimates of Global Warming Potential in Bioenergy Systems of Hawaii: Crop Choice and Deficit Irrigation

    PubMed Central

    Meki, Manyowa N.; Kiniry, James R.; Taylor, Andrew D.; Ogoshi, Richard; Youkhana, Adel; Nakahata, Mae

    2017-01-01

    Replacing fossil fuel with biofuel is environmentally viable from a climate change perspective only if the net greenhouse gas (GHG) footprint of the system is reduced. The effects of replacing annual arable crops with perennial bioenergy feedstocks on net GHG production and soil carbon (C) stock are critical to the system-level balance. Here, we compared GHG flux, crop yield, root biomass, and soil C stock under two potential tropical, perennial grass biofuel feedstocks: conventional sugarcane and ratoon-harvested, zero-tillage napiergrass. Evaluations were conducted at two irrigation levels, 100% of plantation application and at a 50% deficit. Peaks and troughs of GHG emission followed agronomic events such as ratoon harvest of napiergrass and fertilization. Yet, net GHG flux was dominated by carbon dioxide (CO2), as methane was oxidized and nitrous oxide (N2O) emission was very low even following fertilization. High N2O fluxes that frequently negate other greenhouse gas benefits that come from replacing fossil fuels with agronomic forms of bioenergy were mitigated by efficient water and fertilizer management, including direct injection of fertilizer into buried irrigation lines. From soil intensively cultivated for a century in sugarcane, soil C stock and root biomass increased rapidly following cultivation in grasses selected for robust root systems and drought tolerance. The net soil C increase over the two-year crop cycle was three-fold greater than the annualized soil surface CO2 flux. Deficit irrigation reduced yield, but increased soil C accumulation as proportionately more photosynthetic resources were allocated belowground. In the first two years of cultivation napiergrass did not increase net greenhouse warming potential (GWP) compared to sugarcane, and has the advantage of multiple ratoon harvests per year and less negative effects of deficit irrigation to yield. PMID:28052075

  12. Dasytricha dominance in Surti buffalo rumen revealed by 18S rRNA sequences and real-time PCR assay.

    PubMed

    Singh, K M; Tripathi, A K; Pandya, P R; Rank, D N; Kothari, R K; Joshi, C G

    2011-09-01

    The genetic diversity of protozoa in Surti buffalo rumen was studied by amplified ribosomal DNA restriction analysis, 18S rDNA sequence homology and phylogenetic and Real-time PCR analysis methods. Three animals were fed diet comprised green fodder Napier bajra 21 (Pennisetum purpureum), mature pasture grass (Dicanthium annulatum) and concentrate mixture (20% crude protein, 65% total digestible nutrients). A protozoa-specific primer (P-SSU-342f) and a eukarya-specific primer (Medlin B) were used to amplify a 1,360 bp fragment of DNA encoding protozoal small subunit (SSU) ribosomal RNA from rumen fluid. A total of 91 clones were examined and identified 14 different 18S RNA sequences based on PCR-RFLP pattern. These 14 phylotypes were distributed into four genera-based 18S rDNA database sequences and identified as Dasytricha (57 clones), Isotricha (14 clones), Ostracodinium (11 clones) and Polyplastron (9 clones). Phylogenetic analyses were also used to infer the makeup of protozoa communities in the rumen of Surti buffalo. Out of 14 sequences, 8 sequences (69 clones) clustered with the Dasytricha ruminantium-like clone and 4 sequences (13 clones) were also phylogenetically placed with the Isotricha prostoma-like clone. Moreover, 2 phylotypes (9 clones) were related to Polyplastron multivesiculatum-like clone. In addition, the number of 18S rDNA gene copies of Dasytricha ruminantium (0.05% to ciliate protozoa) was higher than Entodinium sp. (2.0 × 10(5) vs. 1.3 × 10(4)) in per ml ruminal fluid.

  13. Grass mulching effect on infiltration, surface runoff and soil loss of three agricultural soils in Nigeria.

    PubMed

    Adekalu, K O; Olorunfemi, I A; Osunbitan, J A

    2007-03-01

    Mulching the soil surface with a layer of plant residue is an effective method of conserving water and soil because it reduces surface runoff, increases infiltration of water into the soil and retard soil erosion. The effectiveness of using elephant grass (Pennisetum purpureum) as mulching material was evaluated in the laboratory using a rainfall simulator set at rainfall intensities typical of the tropics. Six soil samples, two from each of the three major soil series representing the main agricultural soils in South Western Nigeria were collected, placed on three different slopes, and mulched with different rates of the grass. The surface runoff, soil loss, and apparent cumulative infiltration were then measured under each condition. The results with elephant grass compared favorably with results from previous experiments using rice straw. Runoff and soil loss decreased with the amount of mulch used and increased with slope. Surface runoff, infiltration and soil loss had high correlations (R = 0.90, 0.89, and 0.86, respectively) with slope and mulch cover using surface response analysis. The mean surface runoff was correlated negatively with sand content, while mean soil loss was correlated positively with colloidal content (clay and organic matter) of the soil. Infiltration was increased and soil loss was reduced greatly with the highest cover. Mulching the soils with elephant grass residue may benefit late cropping (second cropping) by increasing stored soil water for use during dry weather and help to reduce erosion on sloping land.

  14. Herbaceous energy crops in humid lower South USA

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Prine, G.M.; Woodard, K.R.

    1993-12-31

    The humid lower South has the long warm growing season and high rainfall conditions needed for producing high-yielding perennial herbaceous grasses and shrubs. Many potential biomass plants were evaluated during a ten-year period. Perennial tall grasses such as elephantgrass (Pennisetum purpureum), sugarcane and energycane (Saccharum spp.) and the leguminous shrub Leucaena leucocephala were the highest in biomass production. These perennial crops often have top growth killed by winter freezes and regenerate from underground parts. The tall grasses have high yields because of linear crop growth rates of 18 to 27 g m{sup 2} d{sup {minus}1} for long periods (140 tomore » 196 d) each season. Tall grasses must be planted vegetatively, which is more costly than seed propagation, however, once established, they may persist for many seasons. Oven dry biomass yields have varied from 20 to 45 Mg ha{sup {minus}1} yr{sup {minus}1} in colder subtropical to mild temperate locations to over 60 Mg ha{sup {minus}1} yr{sup {minus}1} in the lower portion of the Florida peninsular. Highest biomass yields have been produced when irrigated with sewage effluent or when grown on phosphatic clay and muck soils in south Florida. The energy content of 1 Mg of oven dry tall grass and leucaena is equivalent to that of about 112 and 123 gallons of number 2 diesel fuel, respectively.« less

  15. N-P-K balance in a milk production system on a C. nlemfuensis grassland and a biomass bank of P. purpureum CT-115 clone

    NASA Astrophysics Data System (ADS)

    Crespo, G.; Rodriguez, I.; Martinez, O.

    2009-04-01

    In very intensive milk production systems in Europe and America with the use of high amounts of chemical fertilizers, the nutrient recycling models consider the losses by leaching and N volatilization, as well as the hydro physical characteristics of the soil affecting the performance of this element (10; 6). However, in more extensive milk production systems, low input agriculture forming the natural cycle occurring within each farm, is of vital importance to potentate nutrient recycling for a stable animal production. The objective is the determination of the values of N, P and K inputs and outputs in a dairy farm with a sward composed by 60% of C. nlemfuensis and 40% of P. purpureum CT-115, associated with legumes in 28% of the area and the balance of these nutrients in the system using the "Recycling" software proposed by Crespo et al (2007). The grassland covered an area of 53.4 ha, composed by C. nlemfuensis (60%), P. purpureum CT-115 (40%) and L. leucocephala and C. cajan legumes intercropped in 28% of the area. The dairy herd consisted of 114 cows, 35 replacement heifers and 24 calves. There was a milk yield of 100 000 litters and the animals consumed 825 t DM from pastures and 75.1 t DM from other supplementary feeds. Nutrients extracted by pastures, nutrients intake by animals from pastures, symbiotically N fixation by legumes and N, P and K determinations outside the system due to animal production were determined (3-11). Volatilized ammonia, nutrient input and litter accumulated in the paddocks were measured once each season of the year. In the whole system the balance indicates negative values of N, P and K. Out of the total amount of nutrients consumed, animals used only 16 kg N, 5 Kg P and 4 Kg K for milk production, LW gain and calf production, the remainder returned to the system through excretions. Hence, more than 90% of the N and K, and approximately 81% of the P consumed by the animals were recycled to the system through the excretions. These

  16. The Challenges and Opportunities Associated with Biofortification of Pearl Millet (Pennisetum glaucum) with Elevated Levels of Grain Iron and Zinc

    PubMed Central

    Manwaring, Hanna R.; Bligh, H. F. J.; Yadav, Rattan

    2016-01-01

    Deficiencies of essential micronutrients such as iron and zinc are the cause of extensive health problems in developing countries. They adversely affect performance, productivity and are a major hindrance to economic development. Since many people who suffer from micronutrient deficiencies are dependent on staple crops to meet their dietary requirements, the development of crop cultivars with increased levels of micronutrients in their edible parts is becoming increasingly recognized as a sustainable solution. This is largely facilitated by genetics and genomic platforms. The cereal crop pearl millet (Pennisetum glaucum), is an excellent candidate for genetic improvement due to its ability to thrive in dry, semi-arid regions, where farming conditions are often unfavorable. Not only does pearl millet grow in areas where other crops such as maize and wheat do not survive, it contains naturally high levels of micronutrients, proteins and a myriad of other health benefitting characteristics. This review discusses the current status of iron and zinc deficiencies and reasons why interventions such as fortification, supplementation, and soil management are neither practicable nor affordable in poverty stricken areas. We argue that the most cost effective, sustainable intervention strategy is to biofortify pearl millet with enhanced levels of bioavailable iron and zinc. We discuss how naturally occurring genetic variations present in germplasm collections can be incorporated into elite, micronutrient rich varieties and what platforms are available to drive this research. We also consider the logistics of transgenic methods that could facilitate the improvement of the pearl millet gene pool. PMID:28066495

  17. Assessing Military Use of Training Areas Using a Geographic Information System

    DTIC Science & Technology

    2010-05-01

    potential impacts to sensitive cultural and natural resources with training activities. Purple amole – Fed. Threatened Arroyo Toad – Fed. Endangered Rock...purple amole o One incident (Nov. 2000) of Engineers driving off-road during wet season and outside dig-zone results in more stringent...Environmental Review process for the TA. Purple Amole (Chlorogalum purpureum var. purpureum) Fed. Threatened, CNPS 1B.1 Photo by Laura Ann Eliassen 6360

  18. Supplementation with Ca salts of soybean oil interacts with concentrate level in grazing dairy cows: milk production and milk composition.

    PubMed

    Macedo, Fernanda Lopes; de Souza, Jonas; Batistel, Fernanda; Chagas, Lucas Jado; Santos, Flávio Augusto Portela

    2016-12-01

    In this study, we investigated the associative effects of concentrate levels and Ca salts of soybean oil (CSSO) supplementation on milk production, milk composition, and milk fatty acids of mid-lactation dairy cows grazing on tropical pasture. Twenty-four Jersey × Holstein cows were used in a randomized block design and assigned to four treatments arranged in a 2 × 2 factorial design. Factors evaluated were concentrate levels (low, 3 kg/day vs. high, 7 kg/day of concentrate) and CSSO supplementation (without CSSO vs. with 250 g CSSO cow/day). All cows grazed on elephant grass (Pennisetum purpureum cv. Cameroon) and received the supplemental treatments for a 90-day period. Interactions between concentrate level and CSSO were detected for milk yield, milk yield components, energy-corrected milk (ECM) and 3.5 % fat-corrected milk (FCM). Milk yield increased when CSSO was fed in a low concentrate level, while it decreased milk production in a high concentrate level. Yields of fat, protein, lactose, 3.5 % FCM, and ECM were not affected with CSSO in the low concentrate, but reduced in the high concentrate level. CSSO increased proportions of monounsaturated milk FA, C18:2 trans-10 cis-12, and polyunsaturated FA, and reduced proportions of saturated milk FA in milk. In conclusion, feeding the high level of concentrate was an effective strategy to improve milk yield and solid production. CSSO supplementation increased milk production when fed at low concentrate level but did not affect yield of solids.

  19. Effects of quebracho tannin extract on intake, digestibility, rumen fermentation, and methane production in crossbred heifers fed low-quality tropical grass.

    PubMed

    Piñeiro-Vázquez, A T; Jiménez-Ferrer, G; Alayon-Gamboa, J A; Chay-Canul, A J; Ayala-Burgos, A J; Aguilar-Pérez, C F; Ku-Vera, J C

    2018-01-01

    The aim of this work was to evaluate the effect of quebracho tannins extract (QTE) on feed intake, dry matter (DM) digestibility, and methane (CH 4 ) emissions in cattle fed low-quality Pennisetum purpureum grass. Five heifers (Bos taurus × Bos indicus) with an average live weight (LW) of 295 ± 19 kg were allotted to five treatments (0, 1, 2, 3, and 4% QTE/kg DM) in a 5 × 5 Latin square design. Intake, digestibility, and total methane emissions (L/day) were recorded for periods of 23 h when cattle were housed in open-circuit respiration chambers. Dry matter intake (DMI), organic matter intake (OMI), dry matter digestibility (DMD), and organic matter digestibility (OMD) were different between treatments with 0 and 4% of QTE/kg DM (P < 0.05). Total volatile fatty acid and the molar proportion of acetate in the rumen was not affected (P < 0.05); however, the molar proportion of propionate increased linearly (P < 0.01) for treatments with 3 and 4% QTE. Total CH 4 production decreased linearly (P < 0.01) as QTE increased in the diet, particularly with 3 and 4% concentration. When expressed as DMI and OMI by CH 4 , production (L/kg) was different between treatments with 0 vs 3 and 4% QTE (P < 0.05). It is concluded that the addition of QTE at 2 or 3% of dry matter ration can decrease methane production up to 29 and 41%, respectively, without significantly compromising feed intake and nutrients digestibility.

  20. Treatment of petroleum drill cuttings using bioaugmentation and biostimulation supplemented with phytoremediation.

    PubMed

    Kogbara, Reginald B; Ogar, Innocent; Okparanma, Reuben N; Ayotamuno, Josiah M

    2016-07-28

    This study sought to compare the effectiveness of bioaugmentation and biostimulation, as well as the combination of both techniques, supplemented with phytoremediation, in the decontamination of petroleum drill cuttings. Drill cuttings with relatively low concentration of total petroleum hydrocarbons (TPH) and metals were mixed with soil in the ratio 5:1 and treated with three different combinations of the bioremediation options. Option A entailed bioaugmentation supplemented with phytoremediation. Option B had the combination of biostimulation and bioaugmentation supplemented with phytoremediation. While biostimulation supplemented with phytoremediation was deployed in option C. Option O containing the drill cuttings-soil mixture without treatment served as untreated control. Fertilizer application, tillage and watering were used for biostimulation treatment, while spent mushroom substrate (Pleurotus ostreatus) and elephant grass (Pennisetum purpureum) were employed for bioaugmentation and phytoremediation treatment, respectively. The drill cuttings-soil mixtures were monitored for TPH, organic carbon, total nitrogen, pH, metal concentrations, and fungal counts, over time. After 56 days of treatment, there was a decline in the initial TPH concentration of 4,114 mg kg(-1) by 5.5%, 68.3%, 75.6% and 48% in options O, A, B and C, respectively. Generally, higher TPH loss resulted from the phytoremediation treatment stage. The treated options also showed slight reductions in metal concentrations ranging from 0% to 16% of the initial low concentrations. The results highlight the effectiveness of bioaugmentation supplemented with phytoremediation. The combination of bioaugmentation and biostimulation supplemented with phytoremediation, however, may prove better in decontaminating petroleum drill cuttings to environmentally benign levels.

  1. Evaluation of the metabolizable energy value for growing lambs of the Mucuna pruriens seed and the whole pod.

    PubMed

    García-Galván, Adan; Belmar-Casso, Roberto; Sarmiento-Franco, Luis; Sandoval-Castro, Carlos Alfredo

    2012-04-01

    Whole pod and seeds of velvet bean (Mucuna pruriens) were included in diets for growing sheep used to validate previously estimated ME values of 9.7 MJ and 12.6 MJ for whole pod and seed respectively. Twenty-four lambs, 15 females and nine males of 18.7 ± 2.4 kg average weight, were allocated in three treatments using a completely randomized block design with eight replicates per treatment. Each group was given a diet with a ratio of 60% of Napier grass (Pennisetum purpureum) and 40% of a supplement with the addition of 0%, 50% whole pod or 66% of M. pruriens seeds, for TI, TII and TIII respectively. Diets were formulated to meet the requirements for 100-g daily live weight gain (LWG). The total dry matter intake (836 g a(-1) d(-1), forage + supplement), LWG (90 g a(-1) d(-1)) and feed conversion (9.66 kg DM/kg LWG) of lambs from TIII were lower (P < 0.05) compared to 941 g, 121 g, and 7.78 kg DM/kg LWG from TII and 976 g, 132 g and 7.50 kg DM/kg LWG from TI respectively. No difference was found (P > 0.05) between TI and TII in the three evaluated variables. The ME values of whole pod and seeds of M. pruriens used in this work were validated. It was concluded that M. pruriens can be included as a component in diets for growing sheep, as a partial replacement of conventional feedstuffs.

  2. Estimation of air-to-grass mass interception factors for iodine.

    PubMed

    Karunakara, N; Ujwal, P; Yashodhara, I; Sudeep Kumara, K; Mohan, M P; Bhaskar Shenoy, K; Geetha, P V; Dileep, B N; James, Joshi P; Ravi, P M

    2018-06-01

    Air-to-grass mass interception factors for radionuclide are important basic input parameter for the estimation of radiation dose to the public around a nuclear power plant. In this paper, we present the determination of air-to- grass mass interception factors for iodine using a 2 m × 2 m × 2 m (l × b × h) size environmental chamber. The temperature, humidity, and rainfall inside the environmental chamber was controlled to required values to simulate different environmental conditions. Grass (Pennisetum purpureum, Schum), grown in pots, was kept inside the environmental chamber and stable iodine in elemental form was sublimed quickly inside the chamber to simulate an accidental release of iodine to the environment. The concentration of iodine in the air was measured periodically by drawing air through a bubbling setup, containing 1% sodium carbonate solution. The mass interception factor for dry deposition varied in the range of 0.25-7.7 m 2  kg -1 with mean value of 2.2 m 2  kg -1 with respect to fresh weight of grass, and that due to wet deposition varied in the range of 0.6-4.8 m 2  kg -1 with mean value of 2.3 m 2  kg -1 . The mass interception factor was inversely correlated with the total iodine deposited through dry deposition as well as with the rainfall. Copyright © 2017. Published by Elsevier Ltd.

  3. Delineation by fluorescence in situ hybridization of a single hemizygous chromosomal region associated with aposporous embryo sac formation in Pennisetum squamulatum and Cenchrus ciliaris.

    PubMed Central

    Goel, Shailendra; Chen, Zhenbang; Conner, Joann A; Akiyama, Yukio; Hanna, Wayne W; Ozias-Akins, Peggy

    2003-01-01

    Apomixis is a means of asexual reproduction by which plants produce embryos without meiosis and fertilization; thus the embryo is of clonal, maternal origin. We previously reported molecular markers showing no recombination with the trait for aposporous embryo sac development in Pennisetum squamulatum and Cenchrus ciliaris, and the collective single-dose alleles defined an apospory-specific genomic region (ASGR). Fluorescence in situ hybridization (FISH) was used to confirm that the ASGR is a hemizygous genomic region and to determine its chromosomal position with respect to rDNA loci and centromere repeats. We also documented chromosome transmission from P. squamulatum in several backcrosses (BCs) with P. glaucum using genomic in situ hybridization (GISH). One to three complete P. squamulatum chromosomes were detected in BC(6), but only one of the three hybridized with the ASGR-linked markers. In P. squamulatum and in all BCs examined, the apospory-linked markers were located in the distal region of the short arm of a single chromosome. All alien chromosomes behaved as univalents during meiosis and segregated randomly in BC(3) and later BC generations, but presence of the ASGR-carrier chromosome alone was sufficient to confer apospory. FISH results support our hypotheses that hemizygosity, proximity to centromeric sequences, and chromosome structure may all play a role in low recombination in the ASGR. PMID:12663545

  4. 7 CFR 201.46 - Weight of working sample.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Mustard: Black 2 20 1,255 India 5 50 625 White 15 150 160 Napiergrass 5 50 Needlegrass, green 7 70 370 Oat... 75 500 40 Dandelion 2 35 1,240 Dill 3 50 800 Eggplant 10 50 230 Endive 3 50 940 Gherkin, West India... 395 Lettuce 3 50 890 Melon 50 500 45 Mustard, India 5 50 625 Mustard, spinach 5 50 535 Okra 100 500 19...

  5. 7 CFR 201.46 - Weight of working sample.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Mustard: Black 2 20 1,255 India 5 50 625 White 15 150 160 Napiergrass 5 50 Needlegrass, green 7 70 370 Oat... 75 500 40 Dandelion 2 35 1,240 Dill 3 50 800 Eggplant 10 50 230 Endive 3 50 940 Gherkin, West India... 395 Lettuce 3 50 890 Melon 50 500 45 Mustard, India 5 50 625 Mustard, spinach 5 50 535 Okra 100 500 19...

  6. 7 CFR 201.46 - Weight of working sample.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Mustard: Black 2 20 1,255 India 5 50 625 White 15 150 160 Napiergrass 5 50 Needlegrass, green 7 70 370 Oat... 75 500 40 Dandelion 2 35 1,240 Dill 3 50 800 Eggplant 10 50 230 Endive 3 50 940 Gherkin, West India... 395 Lettuce 3 50 890 Melon 50 500 45 Mustard, India 5 50 625 Mustard, spinach 5 50 535 Okra 100 500 19...

  7. 7 CFR 201.46 - Weight of working sample.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Mustard: Black 2 20 1,255 India 5 50 625 White 15 150 160 Napiergrass 5 50 Needlegrass, green 7 70 370 Oat... 75 500 40 Dandelion 2 35 1,240 Dill 3 50 800 Eggplant 10 50 230 Endive 3 50 940 Gherkin, West India... 395 Lettuce 3 50 890 Melon 50 500 45 Mustard, India 5 50 625 Mustard, spinach 5 50 535 Okra 100 500 19...

  8. 7 CFR 201.46 - Weight of working sample.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 500 7 Yellow 300 500 9 Manilagrass 2 20 Medic, black 5 50 585 Milkvetch 9 90 270 Millet: Browntop 8 80... Mustard: Black 2 20 1,255 India 5 50 625 White 15 150 160 Napiergrass 5 50 Needlegrass, green 7 70 370 Oat... 535 Winter 10 100 230 Redtop 0.25 2.5 10,695 Rescuegrass 20 200 115 Rhodesgrass 1 10 4,725 Rice 50 500...

  9. In situ phytoextraction of copper and cadmium and its biological impacts in acidic soil.

    PubMed

    Cui, Hongbiao; Fan, Yuchao; Yang, John; Xu, Lei; Zhou, Jing; Zhu, Zhenqiu

    2016-10-01

    Phytoremediation is a potential cost-effective technology for remediating heavy metal-contaminated soils. In this study, we evaluated the biomass and accumulation of copper (Cu) and cadmium (Cd) of plant species grown in a contaminated acidic soil treated with limestone. Five species produced biomass in the order: Pennisetum sinese > Elsholtzia splendens > Vetiveria zizanioides > Setaria pumila > Sedum plumbizincicola. Over one growing season, the best accumulators for Cu and Cd were Pennisetum sinese and Sedum plumbizincicola, respectively. Overall, Pennisetum sinese was the best species for Cu and Cd removal when biomass was considered. However, Elsholtzia splendens soil had the highest enzyme activities and microbial populations, while the biological properties in Pennisetum sinese soil were moderately enhanced. Results would provide valuable insights for phytoremediation of metal-contaminated soils. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Structure, agency, and the transformation of the Sonoran Desert by buffelgrass (Pennisetum ciliare): An application of land change science

    NASA Astrophysics Data System (ADS)

    Brenner, Jacob C.

    A regional land transformation is underway in the Sonoran Desert of southwestern North America as a result of the conversion of native rangeland to exotic pasture. In northwestern Sonora, Mexico the process involves clearing native vegetation for cultivation of buffelgrass (Pennisetum ciliare). Southern African buffelgrass was introduced to Sonora through the United States in the 1950s with generous support from the Mexican federal and Sonoran state governments. The ascendance of buffelgrass as a range management tool in Sonora has been conditioned by an international political economy of beef production. However, land use decisions regarding buffelgrass are also conditioned by factors internal to the ranch household. This research examines the expansion of buffelgrass in the Sonoran Desert, addressing its extent and drivers. Through the use of systematic interviews with ranchers, key informant interviews with government officials, and an examination of northern Mexico's cattle ranching history and policy, the dissertation documents why buffelgrass has spread as a policy program and management choice. This part of the work addresses a "structure-agency debate" in human-environment geography. Next the research turns to landscape impacts of buffelgrass cultivation, through vegetation plot and transect sampling. The extent, cover, and density of buffelgrass inside and outside fenced pastures are examined, confirming the hypothesis that disturbance facilitates invasion from pastures onto surrounding lands. Finally, the research employs novel methods of remote sensing and geographic information science using a 1973-2006 time series of Landsat imagery to characterize the patterns and temporal trajectories of land change by buffelgrass across the site. Object-based image processing techniques are combined with traditional maximum likelihood techniques and classification tree analysis to address the difficult task of distinguishing buffelgrass from other prevalent land

  11. Recycling stabilised/solidified drill cuttings for forage production in acidic soils.

    PubMed

    Kogbara, Reginald B; Dumkhana, Bernard B; Ayotamuno, Josiah M; Okparanma, Reuben N

    2017-10-01

    Stabilisation/solidification (S/S), which involves fixation and immobilisation of contaminants using cementitious materials, is one method of treating drill cuttings before final fate. This work considers reuse of stabilised/solidified drill cuttings for forage production in acidic soils. It sought to improve the sustainability of S/S technique through supplementation with the phytoremediation potential of plants, eliminate the need for landfill disposal and reduce soil acidity for better plant growth. Drill cuttings with an initial total petroleum hydrocarbon (TPH) concentration of 17,125 mg kg -1 and low concentrations of metals were treated with 5%, 10%, and 20% cement dosages. The treated drill cuttings were reused in granular form for growing a forage, elephant grass (Pennisetum purpureum), after mixing with uncontaminated soil. The grasses were also grown in uncontaminated soil. The phytoremediation and growth potential of the plants was assessed over a 12-week period. A mix ratio of one part drill cuttings to three parts uncontaminated soil was required for active plant growth. The phytoremediation ability of elephant grass (alongside abiotic losses) reduced the TPH level (up to 8795 mg kg -1 ) in the soil-treated-drill cuttings mixtures below regulatory (1000 mg kg -1 ) levels. There were also decreased concentrations of metals. The grass showed better heights and leaf lengths in soil containing drill cuttings treated with 5% cement dosage than in uncontaminated soil. The results suggest that recycling S/S treated drill cuttings for forage production may be a potential end use of the treated waste. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Intake and digestion of wethers fed with dwarf elephant grass hay with or without the inclusion of peanut hay.

    PubMed

    Schnaider, Maria Alice; Ribeiro-Filho, Henrique Mendonça Nunes; Vilmar Kozloski, Gilberto; Reiter, Tatiana; Dall Orsoletta, Aline Cristina; Dallabrida, Ademar Luiz

    2014-08-01

    The aim of this study was to evaluate the effect of the inclusion of peanut (Arachis pintoi cv. Amarillo) hay in diets based on dwarf elephant grass (DEG, Pennisetum purpureum Schum cv. Kurumi) hay of different regrowth ages on forage intake and digestibility in wether lambs. The experimental treatments consisted of DEG hay with an interval of regrowth of 30 or 45 days offered as the only feed or in mixture with peanut hay (300 g/kg of total dry matter (DM)), which were tested in eight Texel × Suffolk crossbred wethers in a replicated 4 × 4 Latin square experiment. Both organic matter (OM) and digestible OM intakes were higher (P < 0.05) in animals receiving the legume forage. Total apparent OM digestibility was higher (P < 0.05) at an increased grass regrowth age. Ruminal OM digestibility increased (P < 0.05) with legume inclusion and at a higher grass regrowth age. The nitrogen (N) intake was higher (P < 0.05) in legume treatments and lower (P < 0.05) as the grass regrowth age increased, but retention of N was not affected by treatments. Duodenal flow of both, non-ammonia N and microbial N, were not affected by legume inclusion and were lower (P < 0.05) as grass regrowth age increased. The efficiency of rumen microbial protein synthesis (ERMPS) was negatively affected (P < 0.05) by legume inclusion and was lower (P < 0.05) as the grass regrowth age increased. Supplementation of dwarf elephant grass hay cut at the vegetative stage with peanut legume hay improves nutritional supply to wethers due to an increase in the forage intake.

  13. Recilia banda Kramer (Hemiptera: Cicadellidae), a vector of Napier stunt phytoplasma in Kenya

    NASA Astrophysics Data System (ADS)

    Obura, Evans; Midega, Charles A. O.; Masiga, Daniel; Pickett, John A.; Hassan, Mohamed; Koji, Shinsaku; Khan, Zeyaur R.

    2009-10-01

    Napier grass ( Pennisetum purpureum) is the most important fodder crop in smallholder dairy production systems in East Africa, characterized by small zero-grazing units. It is also an important trap crop used in the management of cereal stemborers in maize in the region. However, production of Napier grass in the region is severely constrained by Napier stunt disease. The etiology of the disease is known to be a phytoplasma, 16SrXI strain. However, the putative insect vector was yet unknown. We sampled and identified five leafhopper and three planthopper species associated with Napier grass and used them as candidates in pathogen transmission experiments. Polymerase chain reaction (PCR), based on the highly conserved 16S gene, primed by P1/P6-R16F2n/R16R2 nested primer sets was used to diagnose phytoplasma on test plants and insects, before and after transmission experiments. Healthy plants were exposed for 60 days to insects that had fed on diseased plants and acquired phytoplasma. The plants were then incubated for another 30 days. Nested PCR analyses showed that 58.3% of plants exposed to Recilia banda Kramer (Hemiptera: Cicadellidae) were positive for phytoplasma and developed characteristic stunt disease symptoms while 60% of R. banda insect samples were similarly phytoplasma positive. We compared the nucleotide sequences of the phytoplasma isolated from R. banda, Napier grass on which these insects were fed, and Napier grass infected by R. banda, and found them to be virtually identical. The results confirm that R. banda transmits Napier stunt phytoplasma in western Kenya, and may be the key vector of Napier stunt disease in this region.

  14. Methane Production of Different Forages in In vitro Ruminal Fermentation

    PubMed Central

    Meale, S. J.; Chaves, A. V.; Baah, J.; McAllister, T. A.

    2012-01-01

    An in vitro rumen batch culture study was completed to compare effects of common grasses, leguminous shrubs and non-leguminous shrubs used for livestock grazing in Australia and Ghana on CH4 production and fermentation characteristics. Grass species included Andropodon gayanus, Brachiaria ruziziensis and Pennisetum purpureum. Leguminous shrub species included Cajanus cajan, Cratylia argentea, Gliricidia sepium, Leucaena leucocephala and Stylosanthes guianensis and non-leguminous shrub species included Annona senegalensis, Moringa oleifera, Securinega virosa and Vitellaria paradoxa. Leaves were harvested, dried at 55°C and ground through a 1 mm screen. Serum bottles containing 500 mg of forage, modified McDougall’s buffer and rumen fluid were incubated under anaerobic conditions at 39°C for 24 h. Samples of each forage type were removed after 0, 2, 6, 12 and 24 h of incubation for determination of cumulative gas production. Methane production, ammonia concentration and proportions of VFA were measured at 24 h. Concentration of aNDF (g/kg DM) ranged from 671 to 713 (grasses), 377 to 590 (leguminous shrubs) and 288 to 517 (non-leguminous shrubs). After 24 h of in vitro incubation, cumulative gas, CH4 production, ammonia concentration, proportion of propionate in VFA and IVDMD differed (p<0.05) within each forage type. B. ruziziensis and G. sepium produced the highest cumulative gas, IVDMD, total VFA, proportion of propionate in VFA and the lowest A:P ratios within their forage types. Consequently, these two species produced moderate CH4 emissions without compromising digestion. Grazing of these two species may be a strategy to reduce CH4 emissions however further assessment in in vivo trials and at different stages of maturity is recommended. PMID:25049482

  15. Development of field-applicable tests for rapid and sensitive detection of Candidatus Phytoplasma oryzae.

    PubMed

    Wambua, Lillian; Schneider, Bernd; Okwaro, Allan; Wanga, Joseph Odhiambo; Imali, Olive; Wambua, Peninah Nduku; Agutu, Lavender; Olds, Cassandra; Jones, Chris Stephen; Masiga, Daniel; Midega, Charles; Khan, Zeyaur; Jores, Joerg; Fischer, Anne

    2017-10-01

    Napier grass Stunt Disease (NSD) is a severe disease of Napier grass (Pennisetum purpureum) in Eastern Africa, caused by the leafhopper-transmitted bacterium Candidatus Phytoplasma oryzae. The pathogen severely impairs the growth of Napier grass, the major fodder for dairy cattle in Eastern Africa. NSD is associated with biomass losses of up to 70% of infected plants. Diagnosis of NSD is done by nested PCR targeting the phytoplasma DNA, which is difficult to perform in developing countries with little infrastructure. We report the development of an easy to use, rapid, sensitive and specific molecular assay for field diagnosis of NSD. The procedure is based on recombinase polymerase amplification and targets the imp gene encoding a pathogen-specific immunodominant membrane protein. Therefore we followed a two-step process. First we developed an isothermal DNA amplification method for real time fluorescence application and then transferred this assay to a lateral flow format. The limit of detection for both procedures was estimated to be 10 organisms. We simplified the template preparation procedure by using freshly squeezed phloem sap from Napier grass. Additionally, we developed a laboratory serological assay with the potential to be converted to a lateral flow assay. Two murine monoclonal antibodies with high affinity and specificity to the immunodominant membrane protein IMP of Candidatus Phytoplasma oryzae were generated. Both antibodies specifically reacted with the denatured or native 17 kDa IMP protein. In dot blot experiments of extracts from infected plant, phytoplasmas were detected in as little as 12,5 μg of fresh plant material. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  16. Development of High Yield Feedstocks and Biomass Conversion Technology for Renewable Energy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hashimoto, Andrew G.; Crow, Susan; DeBeryshe, Barbara

    2015-04-09

    This project had two main goals. The first goal was to evaluate several high yielding tropical perennial grasses as feedstock for biofuel production, and to characterize the feedstock for compatible biofuel production systems. The second goal was to assess the integration of renewable energy systems for Hawaii. The project focused on high-yield grasses (napiergrass, energycane, sweet sorghum, and sugarcane). Field plots were established to evaluate the effects of elevation (30, 300 and 900 meters above sea level) and irrigation (50%, 75% and 100% of sugarcane plantation practice) on energy crop yields and input. The test plots were extensive monitored including:more » hydrologic studies to measure crop water use and losses through seepage and evapotranspiration; changes in soil carbon stock; greenhouse gas flux (CO 2, CH 4, and N 2O) from the soil surface; and root morphology, biomass, and turnover. Results showed significant effects of environment on crop yields. In general, crop yields decrease as the elevation increased, being more pronounced for sweet sorghum and energycane than napiergrass. Also energy crop yields were higher with increased irrigation levels, being most pronounced with energycane and less so with sweet sorghum. Daylight length greatly affected sweet sorghum growth and yields. One of the energy crops (napiergrass) was harvested at different ages (2, 4, 6, and 8 months) to assess the changes in feedstock characteristics with age and potential to generate co-products. Although there was greater potential for co-products from younger feedstock, the increased production was not sufficient to offset the additional cost of harvesting multiple times per year. The feedstocks were also characterized to assess their compatibility with biochemical and thermochemical conversion processes. The project objectives are being continued through additional support from the Office of Naval Research, and the Biomass Research and Development Initiative. Renewable

  17. Cereal domestication and evolution of branching: evidence for soft selection in the Tb1 orthologue of pearl millet (Pennisetum glaucum [L.] R. Br.).

    PubMed

    Remigereau, Marie-Stanislas; Lakis, Ghayas; Rekima, Samah; Leveugle, Magalie; Fontaine, Michaël C; Langin, Thierry; Sarr, Aboubakry; Robert, Thierry

    2011-01-01

    During the Neolithic revolution, early farmers altered plant development to domesticate crops. Similar traits were often selected independently in different wild species; yet the genetic basis of this parallel phenotypic evolution remains elusive. Plant architecture ranks among these target traits composing the domestication syndrome. We focused on the reduction of branching which occurred in several cereals, an adaptation known to rely on the major gene Teosinte-branched1 (Tb1) in maize. We investigate the role of the Tb1 orthologue (Pgtb1) in the domestication of pearl millet (Pennisetum glaucum), an African outcrossing cereal. Gene cloning, expression profiling, QTL mapping and molecular evolution analysis were combined in a comparative approach between pearl millet and maize. Our results in pearl millet support a role for PgTb1 in domestication despite important differences in the genetic basis of branching adaptation in that species compared to maize (e.g. weaker effects of PgTb1). Genetic maps suggest this pattern to be consistent in other cereals with reduced branching (e.g. sorghum, foxtail millet). Moreover, although the adaptive sites underlying domestication were not formerly identified, signatures of selection pointed to putative regulatory regions upstream of both Tb1 orthologues in maize and pearl millet. However, the signature of human selection in the pearl millet Tb1 is much weaker in pearl millet than in maize. Our results suggest that some level of parallel evolution involved at least regions directly upstream of Tb1 for the domestication of pearl millet and maize. This was unanticipated given the multigenic basis of domestication traits and the divergence of wild progenitor species for over 30 million years prior to human selection. We also hypothesized that regular introgression of domestic pearl millet phenotypes by genes from the wild gene pool could explain why the selective sweep in pearl millet is softer than in maize.

  18. Selecting elephant grass families and progenies to produce bioenergy through mixed models (REML/BLUP).

    PubMed

    Rodrigues, E V; Daher, R F; Dos Santos, A; Vivas, M; Machado, J C; Gravina, G do A; de Souza, Y P; Vidal, A K; Rocha, A Dos S; Freitas, R S

    2017-05-18

    Brazil has great potential to produce bioenergy since it is located in a tropical region that receives high incidence of solar energy and presents favorable climatic conditions for such purpose. However, the use of bioenergy in the country is below its productivity potential. The aim of the current study was to select full-sib progenies and families of elephant grass (Pennisetum purpureum S.) to optimize phenotypes relevant to bioenergy production through mixed models (REML/BLUP). The circulating diallel-based crossing of ten elephant grass genotypes was performed. An experimental design using the randomized block methodology, with three repetitions, was set to assess both the hybrids and the parents. Each plot comprised 14-m rows, 1.40 m spacing between rows, and 1.40 m spacing between plants. The number of tillers, plant height, culm diameter, fresh biomass production, dry biomass rate, and the dry biomass production were assessed. Genetic-statistical analyses were performed through mixed models (REML/BLUP). The genetic variance in the assessed families was explained through additive genetic effects and dominance genetic effects; the dominance variance was prevalent. Families such as Capim Cana D'África x Guaçu/I.Z.2, Cameroon x Cuba-115, CPAC x Cuba-115, Cameroon x Guaçu/I.Z.2, and IAC-Campinas x CPAC showed the highest dry biomass production. The family derived from the crossing between Cana D'África and Guaçu/I.Z.2 showed the largest number of potential individuals for traits such as plant height, culm diameter, fresh biomass production, dry biomass production, and dry biomass rate. The individual 5 in the family Cana D'África x Guaçu/I.Z.2, planted in blocks 1 and 2, showed the highest dry biomass production.

  19. Strategic grazing management towards sustainable intensification at tropical pasture-based dairy systems.

    PubMed

    Congio, Guilhermo F S; Batalha, Camila D A; Chiavegato, Marília B; Berndt, Alexandre; Oliveira, Patrícia P A; Frighetto, Rosa T S; Maxwell, Thomas M R; Gregorini, Pablo; Da Silva, Sila C

    2018-05-01

    Agricultural systems are responsible for environmental impacts that can be mitigated through the adoption of more sustainable principles. Our objective was to investigate the influence of two pre-grazing targets (95% and maximum canopy light interception during pasture regrowth; LI 95% and LI Max , respectively) on sward structure and herbage nutritive value of elephant grass cv. Cameroon, and dry matter intake (DMI), milk yield, stocking rate, enteric methane (CH 4 ) emissions by Holstein × Jersey dairy cows. We hypothesized that grazing strategies modifying the sward structure of elephant grass (Pennisetum purpureum Schum.) improves nutritive value of herbage, increasing DMI and reducing intensity of enteric CH 4 emissions, providing environmental and productivity benefits to tropical pasture-based dairy systems. Results indicated that pre-sward surface height was greater for LI Max (≈135 cm) than LI 95% (≈100 cm) and can be used as a reliable field guide for monitoring sward structure. Grazing management based on LI 95% criteria improved herbage nutritive value and grazing efficiency, allowing greater DMI, milk yield and stocking rate by dairy cows. Daily enteric CH 4 emission was not affected; however, cows grazing elephant grass at LI 95% were more efficient and emitted 21% less CH 4 /kg of milk yield and 18% less CH 4 /kg of DMI. The 51% increase in milk yield per hectare overcame the 29% increase in enteric CH 4 emissions per hectare in LI 95% grazing management. Thereby the same resource allocation resulted in a 16% mitigation of the main greenhouse gas from pasture-based dairy systems. Overall, strategic grazing management is an environmental friendly practice that improves use efficiency of allocated resources through optimization of processes evolving plant, ruminant and their interface, and enhances milk production efficiency of tropical pasture-based systems. Copyright © 2018 Elsevier B.V. All rights reserved.

  20. Characteristics of lactic acid bacteria isolates and their effect on the fermentation quality of Napier grass silage at three high temperatures.

    PubMed

    Gulfam, Ali; Guo, Gang; Tajebe, Seare; Chen, Lei; Liu, Qinhua; Yuan, Xianjun; Bai, Yunfeng; Saho, Tao

    2017-04-01

    The poor fermentation quality of silage is an important issue for silage production during the high temperatures of summer. Pediococcus acidilactici GG13 (GG13) and Lactobacillus rhamnosus GG26 (GG26) isolated from Italian ryegrass (Lolium multiflorum Lam.) silage were characterised by morphological and physiological tests and 16S rRNA sequencing analysis, and their effects, along with those of a commercial lactic acid bacteria (LAB) inoculant (CB), on the fermentation quality of facultative halophyte Napier grass (Pennisetum purpureum Schumach) ensiled at 30 °C, 40 °C and 50 °C were studied, respectively. The strains GG13 and GG26 grew well at 50 °C and pH 3.5, and were tolerant to 6.5% NaCl. After ensiling for 50 days, the strains GG13 and GG26 and the CB decreased (P < 0.001) the pH and acetic acid and ammonia-N contents and increased (P < 0.001) the lactic acid contents at 30 °C, and decreased (P < 0.001) the ammonia-N contents at 40 °C in Napier grass. CB did not affect the fermentation quality at 50 °C, whereas both isolated strains improved the fermentation quality of Napier grass silage as indicated by the lower (P < 0.001) pH, butyric acid and ammonia-N contents and higher (P < 0.001) lactic acid contents. The strain GG13 is better than GG26 with regard to improvement in fermentation quality of Napier grass silage. The results of this study suggested that strain GG13 is a good LAB inoculant for producing well-fermented silages during the high temperatures of summer times. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  1. The adsorption kinetics of metal ions onto different microalgae and siliceous earth.

    PubMed

    Schmitt, D; Müller, A; Csögör, Z; Frimmel, F H; Posten, C

    2001-03-01

    In the present work the adsorption kinetics of the six metal ions aluminum, zinc, mercury, lead, copper, and cadmium onto living microalgae were measured. The freshwater green microalga Scenedesmus subspicatus, the brackish water diatom Cyclotella cryptica, the seawater diatom Phaeodactylum tricornutum, and the seawater red alga Porphyridium purpureum were the subject of investigation. In most cases the adsorption rate of the metals could be well described by using the equation of the Langmuir adsorption rate expression. Inverse parameter estimation allowed the determination of the rate constants of the adsorption process and the maximum metal content of the algae. The highest values for the rate constant were obtained for Porphyridium purpureum followed by Phaeodactylum tricornutum. High values for the maximum content were obtained for Cyclotella cryptica and Scenedesmus subspicatus. The maximum rate constant was 24.21 h-1 for the adsorption of Hg to Porphyridium purpureum whereas the maximum metal content (0.243 g g-1) was obtained for Zn on Cyclotella cryptica. A comparison of these values with those obtained for the mineral siliceous earth exhibiting low maximum content and high adsorption rates reveals that the mechanism of adsorption onto the algae is a mixture of adsorption and accumulation.

  2. Evaluation of the grass mixture (Faestuca Rubra, Cynodon Dactylon, Lolium Multiflorum and Pennisetum sp.) as Sb phyto-stabilizer in tailings and Sb-rich soils.

    NASA Astrophysics Data System (ADS)

    Aurora Armienta, M.; Beltrán-Villavicencio, Margarita; Ruiz-Villalobos, Carlos E.; Labastida, Israel; Ceniceros, Nora; Cruz, Olivia; Aguayo, Alejandra

    2017-04-01

    Green house experiments were carried out to evaluate the growth and Sb assimilation of a grass assemblage: Faestuca Rubra, Cynodon Dactylon, Lolium Multiflorum and Pennisetum sp, in tailings and Sb-rich soils. Tailings and soil samples were obtained at the Mexican historical mining zone of Zimapán, Central México. More than 6 tailings impoundments are located at the town outskirts and constitute a contamination source from windblown and waterborne deposit on soils, besides acid mine drainage. Four substrates were used in the experiments: 100% tailings, 20% tailings + 80% soil, 50% tailings + 50% soil , and a soil sample far from tailings as a background. Concentrations of Sb ranged from 310 mg/kg to 413 mg/kg in tailings. A pH of 7.43, 1.27% organic matter, and high concentrations of N, K and P indicated adequate conditions for plant growth. The grass assemblage was raised during 21 days as indicated by OECD (Organisation for Economic Co-operation and Development) Guideline 208 Terrestrial Plant Test: Seedling Emergence and Seedling Growth Test. The highest Sb concentrations were measured in plants grown on tailings with 139 mg/kg in the aerial part and 883 mg/kg in roots. Concentrations of Sb decreased as the proportion of tailings diminished with 22.1 mg/kg in the aerial part and 10 mg/kg in roots corresponding to the plants grown in the 20 % tailings + 80% soil . Bioaccumulation (BAC) and bioconcentration factors (BF) of plants grown on tailings (BAC= 0.42, BCF=3.93) indicated their suitability as a phyto-stabilization option. The grass mixture may be thus applied to control windblown particulate tailings taking advantage to their tolerance to high Sb levels.

  3. Cereal Domestication and Evolution of Branching: Evidence for Soft Selection in the Tb1 Orthologue of Pearl Millet (Pennisetum glaucum [L.] R. Br.)

    PubMed Central

    Remigereau, Marie-Stanislas; Lakis, Ghayas; Rekima, Samah; Leveugle, Magalie; Fontaine, Michaël C.; Langin, Thierry; Sarr, Aboubakry; Robert, Thierry

    2011-01-01

    Background During the Neolithic revolution, early farmers altered plant development to domesticate crops. Similar traits were often selected independently in different wild species; yet the genetic basis of this parallel phenotypic evolution remains elusive. Plant architecture ranks among these target traits composing the domestication syndrome. We focused on the reduction of branching which occurred in several cereals, an adaptation known to rely on the major gene Teosinte-branched1 (Tb1) in maize. We investigate the role of the Tb1 orthologue (Pgtb1) in the domestication of pearl millet (Pennisetum glaucum), an African outcrossing cereal. Methodology/Principal Findings Gene cloning, expression profiling, QTL mapping and molecular evolution analysis were combined in a comparative approach between pearl millet and maize. Our results in pearl millet support a role for PgTb1 in domestication despite important differences in the genetic basis of branching adaptation in that species compared to maize (e.g. weaker effects of PgTb1). Genetic maps suggest this pattern to be consistent in other cereals with reduced branching (e.g. sorghum, foxtail millet). Moreover, although the adaptive sites underlying domestication were not formerly identified, signatures of selection pointed to putative regulatory regions upstream of both Tb1 orthologues in maize and pearl millet. However, the signature of human selection in the pearl millet Tb1 is much weaker in pearl millet than in maize. Conclusions/Significance Our results suggest that some level of parallel evolution involved at least regions directly upstream of Tb1 for the domestication of pearl millet and maize. This was unanticipated given the multigenic basis of domestication traits and the divergence of wild progenitor species for over 30 million years prior to human selection. We also hypothesized that regular introgression of domestic pearl millet phenotypes by genes from the wild gene pool could explain why the selective

  4. Recent mobility of plastid encoded group II introns and twintrons in five strains of the unicellular red alga Porphyridium

    PubMed Central

    Perrineau, Marie-Mathilde; Price, Dana C.; Mohr, Georg

    2015-01-01

    Group II introns are closely linked to eukaryote evolution because nuclear spliceosomal introns and the small RNAs associated with the spliceosome are thought to trace their ancient origins to these mobile elements. Therefore, elucidating how group II introns move, and how they lose mobility can potentially shed light on fundamental aspects of eukaryote biology. To this end, we studied five strains of the unicellular red alga Porphyridium purpureum that surprisingly contain 42 group II introns in their plastid genomes. We focused on a subset of these introns that encode mobility-conferring intron-encoded proteins (IEPs) and found them to be distributed among the strains in a lineage-specific manner. The reverse transcriptase and maturase domains were present in all lineages but the DNA endonuclease domain was deleted in vertically inherited introns, demonstrating a key step in the loss of mobility. P. purpureum plastid intron RNAs had a classic group IIB secondary structure despite variability in the DIII and DVI domains. We report for the first time the presence of twintrons (introns-within-introns, derived from the same mobile element) in Rhodophyta. The P. purpureum IEPs and their mobile introns provide a valuable model for the study of mobile retroelements in eukaryotes and offer promise for biotechnological applications. PMID:26157604

  5. Pearl millet [Pennisetum glaucum (L.) R. Br.] consensus linkage map constructed using four RIL mapping populations and newly developed EST-SSRs.

    PubMed

    Rajaram, Vengaldas; Nepolean, Thirunavukkarasu; Senthilvel, Senapathy; Varshney, Rajeev K; Vadez, Vincent; Srivastava, Rakesh K; Shah, Trushar M; Supriya, Ambawat; Kumar, Sushil; Ramana Kumari, Basava; Bhanuprakash, Amindala; Narasu, Mangamoori Lakshmi; Riera-Lizarazu, Oscar; Hash, Charles Thomas

    2013-03-09

    Pearl millet [Pennisetum glaucum (L.) R. Br.] is a widely cultivated drought- and high-temperature tolerant C4 cereal grown under dryland, rainfed and irrigated conditions in drought-prone regions of the tropics and sub-tropics of Africa, South Asia and the Americas. It is considered an orphan crop with relatively few genomic and genetic resources. This study was undertaken to increase the EST-based microsatellite marker and genetic resources for this crop to facilitate marker-assisted breeding. Newly developed EST-SSR markers (99), along with previously mapped EST-SSR (17), genomic SSR (53) and STS (2) markers, were used to construct linkage maps of four F7 recombinant inbred populations (RIP) based on crosses ICMB 841-P3 × 863B-P2 (RIP A), H 77/833-2 × PRLT 2/89-33 (RIP B), 81B-P6 × ICMP 451-P8 (RIP C) and PT 732B-P2 × P1449-2-P1 (RIP D). Mapped loci numbers were greatest for RIP A (104), followed by RIP B (78), RIP C (64) and RIP D (59). Total map lengths (Haldane) were 615 cM, 690 cM, 428 cM and 276 cM, respectively. A total of 176 loci detected by 171 primer pairs were mapped among the four crosses. A consensus map of 174 loci (899 cM) detected by 169 primer pairs was constructed using MergeMap to integrate the individual linkage maps. Locus order in the consensus map was well conserved for nearly all linkage groups. Eighty-nine EST-SSR marker loci from this consensus map had significant BLAST hits (top hits with e-value ≤ 1E-10) on the genome sequences of rice, foxtail millet, sorghum, maize and Brachypodium with 35, 88, 58, 48 and 38 loci, respectively. The consensus map developed in the present study contains the largest set of mapped SSRs reported to date for pearl millet, and represents a major consolidation of existing pearl millet genetic mapping information. This study increased numbers of mapped pearl millet SSR markers by >50%, filling important gaps in previously published SSR-based linkage maps for this species and will greatly

  6. Effectiveness of narrow grass hedges in reducing atrazine runoff under different slope gradient conditions.

    PubMed

    Wang, Qinghai; Li, Cui; Chen, Chao; Chen, Jie; Zheng, Ruilun; Que, Xiaoe

    2018-03-01

    Atrazine is frequently detected in surface runoff and poses a potential threat to the environment. Grass hedges may minimize runoff loss of atrazine from crop fields. Therefore, the effectiveness of two grass hedges (Melilotus albus and Pennisetum alopecuroides) in controlling atrazine runoff was investigated using simulated rainfall on lands at different slope gradients (15 and 20%) in northern China. Results showed that a storm (40 mm in 1 h), occurring 4 h after atrazine application, caused a loss of 3% of the applied amount. Atrazine loss under 20% slope was significantly greater than that under 15% slope in control plots. Atrazine exports associated with the water fraction accounted for the majority of total loss. Pennisetum hedges were more efficient in controlling atrazine loss with runoff compared to Melilotus hedges. No significant difference in the capacity of grass hedges to reduce atrazine exports was observed between 15 and 20% slopes. These findings suggest grass hedges are effective in minimizing atrazine runoff in northern China, and Pennisetum hedges should be preferentially used on sloping croplands in similar climatic regions.

  7. Multi-scale measurements show limited soil greenhouse gas emissions in Kenyan smallholder coffee-dairy systems.

    PubMed

    Ortiz-Gonzalo, Daniel; de Neergaard, Andreas; Vaast, Philippe; Suárez-Villanueva, Víctor; Oelofse, Myles; Rosenstock, Todd S

    2018-06-01

    Efforts have been made in recent years to improve knowledge about soil greenhouse gas (GHG) fluxes from sub-Saharan Africa. However, data on soil GHG emissions from smallholder coffee-dairy systems have not hitherto been measured experimentally. This study aimed to quantify soil GHG emissions at different spatial and temporal scales in smallholder coffee-dairy farms in Murang'a County, Central Kenya. GHG measurements were carried out for one year, comprising two cropping seasons, using vented static chambers and gas chromatography. Sixty rectangular frames were installed on two farms comprising the three main cropping systems found in the area: 1) coffee (Coffea arabica L.); 2) Napier grass (Pennisetum purpureum); and 3) maize intercropped with beans (Zea mays and Phaseolus vulgaris). Within these fields, chambers were allocated on fertilised and unfertilised locations to capture spatial variability. Cumulative annual fluxes in coffee plots ranged from 1 to 1.9kgN 2 O-Nha -1 , 6.5 to 7.6MgCO 2 -Cha -1 and - 3.4 to -2.2kgCH 4 -Cha -1 , with 66% to 94% of annual GHG fluxes occurring during rainy seasons. Across the farm plots, coffee received most of the N inputs and had 56% to 89% higher emissions of N 2 O than Napier grass, maize and beans. Within farm plots, two to six times higher emissions were found in fertilised hotspots - around the perimeter of coffee trees or within planted maize rows - than in unfertilised locations between trees, rows and planting holes. Background and induced soil N 2 O emissions from fertiliser and manure applications in the three cropping systems were lower than hypothesized from previous studies and empirical models. This study supplements methods and underlying data for the quantification of GHG emissions at multiple spatial and temporal scales in tropical, smallholder farming systems. Advances towards overcoming the dearth of data will facilitate the understanding of synergies and tradeoffs of climate-smart approaches for low

  8. A segment of the apospory-specific genomic region is highly microsyntenic not only between the apomicts Pennisetum squamulatum and buffelgrass, but also with a rice chromosome 11 centromeric-proximal genomic region.

    PubMed

    Gualtieri, Gustavo; Conner, Joann A; Morishige, Daryl T; Moore, L David; Mullet, John E; Ozias-Akins, Peggy

    2006-03-01

    Bacterial artificial chromosome (BAC) clones from apomicts Pennisetum squamulatum and buffelgrass (Cenchrus ciliaris), isolated with the apospory-specific genomic region (ASGR) marker ugt197, were assembled into contigs that were extended by chromosome walking. Gene-like sequences from contigs were identified by shotgun sequencing and BLAST searches, and used to isolate orthologous rice contigs. Additional gene-like sequences in the apomicts' contigs were identified by bioinformatics using fully sequenced BACs from orthologous rice contigs as templates, as well as by interspecies, whole-contig cross-hybridizations. Hierarchical contig orthology was rapidly assessed by constructing detailed long-range contig molecular maps showing the distribution of gene-like sequences and markers, and searching for microsyntenic patterns of sequence identity and spatial distribution within and across species contigs. We found microsynteny between P. squamulatum and buffelgrass contigs. Importantly, this approach also enabled us to isolate from within the rice (Oryza sativa) genome contig Rice A, which shows the highest microsynteny and is most orthologous to the ugt197-containing C1C buffelgrass contig. Contig Rice A belongs to the rice genome database contig 77 (according to the current September 12, 2003, rice fingerprint contig build) that maps proximal to the chromosome 11 centromere, a feature that interestingly correlates with the mapping of ASGR-linked BACs proximal to the centromere or centromere-like sequences. Thus, relatedness between these two orthologous contigs is supported both by their molecular microstructure and by their centromeric-proximal location. Our discoveries promote the use of a microsynteny-based positional-cloning approach using the rice genome as a template to aid in constructing the ASGR toward the isolation of genes underlying apospory.

  9. Field-based estimates of global warming potential in bioenergy systems of Hawaii: Crop choice and deficit irrigation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Pawlowski, Meghan N.; Crow, Susan E.; Meki, Manyowa N.

    Replacing fossil fuel with biofuel is environmentally viable from a climate change perspective only if the net greenhouse gas (GHG) footprint of the system is reduced. The effects of replacing annual arable crops with perennial bioenergy feedstocks on net GHG production and soil carbon (C) stock are critical to the system-level balance. Here, we compared GHG flux, crop yield, root biomass, and soil C stock under two potential tropical, perennial grass biofuel feedstocks: conventional sugarcane and ratoon-harvested, zero-tillage napiergrass. Evaluations were conducted at two irrigation levels, 100% of plantation application and at a 50% deficit. Peaks and troughs of GHGmore » emission followed agronomic events such as ratoon harvest of napiergrass and fertilization. Yet, net GHG flux was dominated by carbon dioxide (CO 2), as methane was oxidized and nitrous oxide (N 2O) emission was very low even following fertilization. High N 2O fluxes that frequently negate other greenhouse gas benefits that come from replacing fossil fuels with agronomic forms of bioenergy were mitigated by efficient water and fertilizer management, including direct injection of fertilizer into buried irrigation lines. From soil intensively cultivated for a century in sugarcane, soil C stock and root biomass increased rapidly following cultivation in grasses selected for robust root systems and drought tolerance. The net soil C increase over the two-year crop cycle was three-fold greater than the annualized soil surface CO 2 flux. Furthermore, deficit irrigation reduced yield, but increased soil C accumulation as proportionately more photosynthetic resources were allocated below ground. In the first two years of cultivation napier grass did not increase net greenhouse warming potential (GWP) compared to sugarcane, and has the advantage of multiple ratoon harvests per year and less negative effects of deficit irrigation to yield.« less

  10. Field-based estimates of global warming potential in bioenergy systems of Hawaii: Crop choice and deficit irrigation

    DOE PAGES

    Pawlowski, Meghan N.; Crow, Susan E.; Meki, Manyowa N.; ...

    2017-01-04

    Replacing fossil fuel with biofuel is environmentally viable from a climate change perspective only if the net greenhouse gas (GHG) footprint of the system is reduced. The effects of replacing annual arable crops with perennial bioenergy feedstocks on net GHG production and soil carbon (C) stock are critical to the system-level balance. Here, we compared GHG flux, crop yield, root biomass, and soil C stock under two potential tropical, perennial grass biofuel feedstocks: conventional sugarcane and ratoon-harvested, zero-tillage napiergrass. Evaluations were conducted at two irrigation levels, 100% of plantation application and at a 50% deficit. Peaks and troughs of GHGmore » emission followed agronomic events such as ratoon harvest of napiergrass and fertilization. Yet, net GHG flux was dominated by carbon dioxide (CO 2), as methane was oxidized and nitrous oxide (N 2O) emission was very low even following fertilization. High N 2O fluxes that frequently negate other greenhouse gas benefits that come from replacing fossil fuels with agronomic forms of bioenergy were mitigated by efficient water and fertilizer management, including direct injection of fertilizer into buried irrigation lines. From soil intensively cultivated for a century in sugarcane, soil C stock and root biomass increased rapidly following cultivation in grasses selected for robust root systems and drought tolerance. The net soil C increase over the two-year crop cycle was three-fold greater than the annualized soil surface CO 2 flux. Furthermore, deficit irrigation reduced yield, but increased soil C accumulation as proportionately more photosynthetic resources were allocated below ground. In the first two years of cultivation napier grass did not increase net greenhouse warming potential (GWP) compared to sugarcane, and has the advantage of multiple ratoon harvests per year and less negative effects of deficit irrigation to yield.« less

  11. A Segment of the Apospory-Specific Genomic Region Is Highly Microsyntenic Not Only between the Apomicts Pennisetum squamulatum and Buffelgrass, But Also with a Rice Chromosome 11 Centromeric-Proximal Genomic Region1[W

    PubMed Central

    Gualtieri, Gustavo; Conner, Joann A.; Morishige, Daryl T.; Moore, L. David; Mullet, John E.; Ozias-Akins, Peggy

    2006-01-01

    Bacterial artificial chromosome (BAC) clones from apomicts Pennisetum squamulatum and buffelgrass (Cenchrus ciliaris), isolated with the apospory-specific genomic region (ASGR) marker ugt197, were assembled into contigs that were extended by chromosome walking. Gene-like sequences from contigs were identified by shotgun sequencing and BLAST searches, and used to isolate orthologous rice contigs. Additional gene-like sequences in the apomicts' contigs were identified by bioinformatics using fully sequenced BACs from orthologous rice contigs as templates, as well as by interspecies, whole-contig cross-hybridizations. Hierarchical contig orthology was rapidly assessed by constructing detailed long-range contig molecular maps showing the distribution of gene-like sequences and markers, and searching for microsyntenic patterns of sequence identity and spatial distribution within and across species contigs. We found microsynteny between P. squamulatum and buffelgrass contigs. Importantly, this approach also enabled us to isolate from within the rice (Oryza sativa) genome contig Rice A, which shows the highest microsynteny and is most orthologous to the ugt197-containing C1C buffelgrass contig. Contig Rice A belongs to the rice genome database contig 77 (according to the current September 12, 2003, rice fingerprint contig build) that maps proximal to the chromosome 11 centromere, a feature that interestingly correlates with the mapping of ASGR-linked BACs proximal to the centromere or centromere-like sequences. Thus, relatedness between these two orthologous contigs is supported both by their molecular microstructure and by their centromeric-proximal location. Our discoveries promote the use of a microsynteny-based positional-cloning approach using the rice genome as a template to aid in constructing the ASGR toward the isolation of genes underlying apospory. PMID:16415213

  12. Effect of sources of calcium salts of fatty acids on production, nutrient digestibility, energy balance, and carryover effects of early lactation grazing dairy cows.

    PubMed

    de Souza, Jonas; Batistel, Fernanda; Santos, Flávio Augusto Portela

    2017-02-01

    The objective of our study was to investigate the effects of sources of calcium salts of fatty acids (FA) on production, nutrient digestibility, energy balance, and carryover effects of early lactation grazing dairy cows. Treatment diets were offered from 3 to 16 wk postpartum (the treatment period), in which all cows grazed elephantgrass (Pennisetum purpureum 'Cameroon') and treatments were added to a concentrate supplement. The treatments were (1) control (concentrate without supplemental fat); (2) concentrate with calcium salts of soybean FA (CSSO); and (3) concentrate with calcium salts of palm FA (CSPO). From 17 to 42 wk postpartum (the carryover period), all cows received a common diet fed as a total mixed ration. During the treatment period, CSPO increased milk yield, milk fat yield, 3.5% fat-corrected milk, energy-corrected milk, and cumulative milk yield compared with control and CSSO. Treatment CSSO increased the yield of milk but did not affect 3.5% fat-corrected milk or energy-corrected compared with control. Also, CSSO decreased milk fat yield, dry matter intake, neutral detergent fiber digestibility, and body weight and body condition loss. Compared with control, both CSSO and CSPO increased feed efficiency (3.5% fat-corrected milk:dry matter intake), and CSPO increased feed efficiency compared with CSSO. When considering energy partitioning (as % energy intake), CSPO increased energy partitioning toward milk and increased energy mobilized from body reserves compared with control and CSSO. Furthermore, CSSO tended to reduce the mobilization of energy from body reserves compared with control. In the carryover period, no differences in milk composition were observed among treatments. A treatment by time interaction was observed during the carryover period for milk yield because cows on CSPO maintained higher production compared with control and CSSO cows until 30 wk postpartum; CSSO had a lower carryover effect sustaining higher milk yield compared with

  13. Reversing land degradation through grasses: a systematic meta-analysis in the Indian tropics

    NASA Astrophysics Data System (ADS)

    Mandal, Debashis; Srivastava, Pankaj; Giri, Nishita; Kaushal, Rajesh; Cerda, Artemi; Meherul Alam, Nurnabi

    2017-02-01

    Although intensive agriculture is necessary to sustain the world's growing population, accelerated soil erosion contributes to a decrease in the environmental health of ecosystems at local, regional and global scales. Reversing the process of land degradation using vegetative measures is of utmost importance in such ecosystems. The present study critically analyzes the effect of grasses in reversing the process of land degradation using a systematic review. The collected information was segregated under three different land use and land management situations. Meta-analysis was applied to test the hypothesis that the use of grasses reduces runoff and soil erosion. The effect of grasses was deduced for grass strip and in combination with physical structures. Similarly, the effects of grasses were analyzed in degraded pasture lands. The overall result of the meta-analysis showed that infiltration capacity increased approximately 2-fold after planting grasses across the slopes in agricultural fields. Grazing land management through a cut-and-carry system increased conservation efficiencies by 42 and 63 % with respect to reduction in runoff and erosion, respectively. Considering the comprehensive performance index (CPI), it has been observed that hybrid Napier (Pennisetum purpureum) and sambuta (Saccharum munja) grass seem to posses the most desirable attributes as an effective grass barrier for the western Himalayas and Eastern Ghats, while natural grass (Dichanthium annulatum) and broom grass (Thysanolaena maxima) are found to be most promising grass species for the Konkan region of the Western Ghats and the northeastern Himalayan region, respectively. In addition to these benefits, it was also observed that soil carbon loss can be reduced by 83 % with the use of grasses. Overall, efficacy for erosion control of various grasses was more than 60 %; hence, their selection should be based on the production potential of these grasses under given edaphic and agro

  14. Evaluating the composition and processing potential of novel sources of Brazilian biomass for sustainable biorenewables production

    PubMed Central

    2014-01-01

    Background The search for promising and renewable sources of carbohydrates for the production of biofuels and other biorenewables has been stimulated by an increase in global energy demand in the face of growing concern over greenhouse gas emissions and fuel security. In particular, interest has focused on non-food lignocellulosic biomass as a potential source of abundant and sustainable feedstock for biorefineries. Here we investigate the potential of three Brazilian grasses (Panicum maximum, Pennisetum purpureum and Brachiaria brizantha), as well as bark residues from the harvesting of two commercial Eucalyptus clones (E. grandis and E. grandis x urophylla) for biofuel production, and compare these to sugarcane bagasse. The effects of hot water, acid, alkaline and sulfite pretreatments (at increasing temperatures) on the chemical composition, morphology and saccharification yields of these different biomass types were evaluated. Results The average yield (per hectare), availability and general composition of all five biomasses were compared. Compositional analyses indicate a high level of hemicellulose and lignin removal in all grass varieties (including sugarcane bagasse) after acid and alkaline pretreatment with increasing temperatures, whilst the biomasses pretreated with hot water or sulfite showed little variation from the control. For all biomasses, higher cellulose enrichment resulted from treatment with sodium hydroxide at 130°C. At 180°C, a decrease in cellulose content was observed, which is associated with high amorphous cellulose removal and 5-hydroxymethyl-furaldehyde production. Morphological analysis showed the effects of different pretreatments on the biomass surface, revealing a high production of microfibrillated cellulose on grass surfaces, after treatment with 1% sodium hydroxide at 130°C for 30 minutes. This may explain the higher hydrolysis yields resulting from these pretreatments, since these cellulosic nanoparticles can be easily

  15. Allometric Models for Predicting Aboveground Biomass and Carbon Stock of Tropical Perennial C 4 Grasses in Hawaii

    DOE PAGES

    Youkhana, Adel H.; Ogoshi, Richard M.; Kiniry, James R.; ...

    2017-05-02

    Biomass is a promising renewable energy option that provides a more environmentally sustainable alternative to fossil resources by reducing the net flux of greenhouse gasses to the atmosphere. Yet, allometric models that allow the prediction of aboveground biomass (AGB), biomass carbon (C) stock non-destructively have not yet been developed for tropical perennial C 4 grasses currently under consideration as potential bioenergy feedstock in Hawaii and other subtropical and tropical locations. The objectives of this study were to develop optimal allometric relationships and site-specific models to predict AGB, biomass C stock of napiergrass, energycane, and sugarcane under cultivation practices for renewablemore » energy and validate these site-specific models against independent data sets generated from sites with widely different environments. Several allometric models were developed for each species from data at a low elevation field on the island of Maui, Hawaii. A simple power model with stalk diameter (D) was best related to AGB and biomass C stock for napiergrass, energycane, and sugarcane, (R 2 = 0.98, 0.96, and 0.97, respectively). The models were then tested against data collected from independent fields across an environmental gradient. For all crops, the models over-predicted AGB in plants with lower stalk D, but AGB was under-predicted in plants with higher stalk D. The models using stalk D were better for biomass prediction compared to dewlap H (Height from the base cut to most recently exposed leaf dewlap) models, which showed weak validation performance. Although stalk D model performed better, however, the mean square error (MSE)-systematic was ranged from 23 to 43 % of MSE for all crops. A strong relationship between model coefficient and rainfall was existed, although these were irrigated systems; suggesting a simple site-specific coefficient modulator for rainfall to reduce systematic errors in water-limited areas. These allometric equations

  16. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Youkhana, Adel H.; Ogoshi, Richard M.; Kiniry, James R.

    Biomass is a promising renewable energy option that provides a more environmentally sustainable alternative to fossil resources by reducing the net flux of greenhouse gasses to the atmosphere. Yet, allometric models that allow the prediction of aboveground biomass (AGB), biomass carbon (C) stock non-destructively have not yet been developed for tropical perennial C 4 grasses currently under consideration as potential bioenergy feedstock in Hawaii and other subtropical and tropical locations. The objectives of this study were to develop optimal allometric relationships and site-specific models to predict AGB, biomass C stock of napiergrass, energycane, and sugarcane under cultivation practices for renewablemore » energy and validate these site-specific models against independent data sets generated from sites with widely different environments. Several allometric models were developed for each species from data at a low elevation field on the island of Maui, Hawaii. A simple power model with stalk diameter (D) was best related to AGB and biomass C stock for napiergrass, energycane, and sugarcane, (R 2 = 0.98, 0.96, and 0.97, respectively). The models were then tested against data collected from independent fields across an environmental gradient. For all crops, the models over-predicted AGB in plants with lower stalk D, but AGB was under-predicted in plants with higher stalk D. The models using stalk D were better for biomass prediction compared to dewlap H (Height from the base cut to most recently exposed leaf dewlap) models, which showed weak validation performance. Although stalk D model performed better, however, the mean square error (MSE)-systematic was ranged from 23 to 43 % of MSE for all crops. A strong relationship between model coefficient and rainfall was existed, although these were irrigated systems; suggesting a simple site-specific coefficient modulator for rainfall to reduce systematic errors in water-limited areas. These allometric equations

  17. MEIOTIC BEHAVIOR OF PLATINUM-INDUCED ANEUPLOIDS IN PEARL MILLET

    EPA Science Inventory

    Cytotoxicity, measured by seed germination and seedling survival, and the clastogenic potential of platinum diaminodinitrodichloride were evaluated in pear millet (Pennisetum americanum (k) Schum). The study was conducted under controlled climatic conditions. Presoaked seed of pe...

  18. Novel application of ALMANAC: Modelling a functional group, exotic warm-season perennial grasses

    USDA-ARS?s Scientific Manuscript database

    Introduced perennial C4 grasses such buffelgrass (Pennisetum ciliare [(L.) Link]) and old world bluestems (OWB), including genera such as Bothriochloa Kuntze, Capillipedium Stapf, and Dichanthium Willemet have the potential to dominate landscapes. A process-based model that realistically simulates ...

  19. A Regional Guidebook for Applying the Hydrogeomorphic Approach to Assessing Wetland Functions of Prairie Potholes

    DTIC Science & Technology

    2006-05-01

    glyptosperma ribseed sandmat 0 Euphorbia maculata Spotted Spurge 0 Euthamia graminifolia Flat-top Goldentop 6 Fragaria virginiana Wild Strawberry 4...Foxtail UK Setaria viridis Pennisetum viridis Green Foxtail 0 Silene sp. Catchfly UK Sisyrinchium campestre White-eyed Grass 10 Sium suave

  20. INDUCTION OF TRISOMICS BY PLATINUM DIAMINODINITRODICHLORIDE

    EPA Science Inventory

    Trisomics were produced in the pollen mother cells of Pennisetum americanum (L) K. Schum plants resulting from seeds treated with M to the minus 6th power platinum diaminodinitrodichloride. On the basis of the preliminary study the relative potency of cis-Platinum diaminodinitrod...

  1. Genetic diversity among pentaploid buffelgrass accessions

    USDA-ARS?s Scientific Manuscript database

    Buffelgrass (Pennisetum ciliare) is an important range and pasture grass that grows in the arid tropics and semi-tropics. It has excellent drought tolerance but lacks winter hardiness. Even though the grass reproduces primarily by apomixis, it is highly polymorphic. A range of chromosome numbers ...

  2. Functional diversity in summer annual grass and legume intercrops in the Northeastern United States

    USDA-ARS?s Scientific Manuscript database

    A warm-season annual intercropping experiment was conducted across the Northeastern United States with four trials in 2013 and five trials in 2014 with four crop species selected based on differences in stature and nitrogen acquisition traits: 1) pearl millet (Pennisetum glaucum L.); 2) sorghum suda...

  3. Soil greenhouse gas (GHG) emissions from smallholder crop-livestock systems in Central Kenya

    NASA Astrophysics Data System (ADS)

    Ortiz Gonzalo, Daniel; Vaast, Philippe; de Neergaard, Andreas; Oelofse, Myles; Albrecht, Alain; Rosenstock, Todd S.

    2017-04-01

    Few studies measured empirically greenhouse gas (GHG) emissions in sub-Saharan Africa. More specifically, there is no experimental data on GHG emissions from coffee systems in East Africa and estimations with GHG calculators have shown some limitations. The objectives of our study are to: 1) Quantify soil GHG fluxes in smallholder coffee-dairy farms in Central Kenya and; 2) Compare results with the GHG emissions estimated with GHG calculators. The study area is situated in Murang'a County at 1700 m.a.s.l. on the Eastern slopes of the Aberdares Range, where coffee (Coffee arabica) is cultivated within integrated crop-livestock-agroforestry systems. We carried out GHG measurements along two cropping seasons using non-flow through non-steady static chambers. Sixty rectangular frames (0.355m x 0.255m) were installed at two representative farms, including the three main cropping systems found in the area: 1) Coffee (Coffee arabica); 2) Napier grass (Pennisetum purpureum); 3) Maize intercropped with beans (Zea mays and Phaseolus vulgaris). We used the gas pooling technique to overcome spatial variability and obtain a composite sample from the two treatment chambers: fertilized and non-fertilized. The sampling was performed twice per week during the rainy season and once per week during the dry season. Fertilizer and manure applications were followed by daily measurements during seven days after application. Annual fluxes (cumulative) in coffee plots ranged from 0.8 to 2.1 kg N2O-N ha-1, 6.3 to 8.2 Mg CO2-C ha-1 and -1.3 to -0.8 kg CH4-C ha-1, with higher fluxes during the rainy seasons. Emissions of N2O and CO2 from coffee plots were 20 to 80% higher than those in maize and napier grass. We found significant higher emissions in fertilized hot-spots (45 -190 % higher around coffee bushes perimeter, within maize rows and in napier holes) than in non-fertilized locations (between trees, between rows and between holes). Though this aspect is crucial for upscaling the

  4. Searching for microbial biological control candidates for invasive grasses: coupling expanded field research with strides in biotechnology and grassland restoration

    USDA-ARS?s Scientific Manuscript database

    Highly invasive grasses (e.g. Bromus spp., Pennisetum ciliare, Taeniatherum caput-medusae) are largely unabated in much of the arid Western U.S., despite more than 70 years of control attempts with a wide array of tools and management practices. The development and sustained integration of new appro...

  5. Ploidy determination of buffel grass accessions in the USDA National Plant Germplasm System collection by flow cytometry

    USDA-ARS?s Scientific Manuscript database

    Buffelgrass [Pennisetum ciliare (L.) Link syn. Cenchrus ciliaris L.] is an important forage and range grass in many of the semi-arid tropical and subtropical regions of the world. The species reproduces primarily by apomixis but it is highly diverse because a wide array of different apomictic ecoty...

  6. Cochliotoxin, a Dihydropyranopyran-4,5-dione, and its analogues produced by Cochliobolus australiensis display phytotoxic activity against buffelgrass (Cenchrus ciliaris)

    Treesearch

    Marco Masi; Susan Meyer; Suzette Clement; Alessio Cimmino; Massimo Cristofaro; Antonio Evidente

    2017-01-01

    Buffelgrass (Pennisetum ciliare or Cenchrus ciliaris) is a perennial grass that has become highly invasive in the Sonoran Desert of southern Arizona. In the search for novel control strategies against this weed, strains of the foliar fungal pathogen Cochliobolus australiensis from buffelgrass have been screened for their ability to produce phytotoxic metabolites that...

  7. Lipid metabolism and potentials of biofuel and high added-value oil production in red algae.

    PubMed

    Sato, Naoki; Moriyama, Takashi; Mori, Natsumi; Toyoshima, Masakazu

    2017-04-01

    Biomass production is currently explored in microalgae, macroalgae and land plants. Microalgal biofuel development has been performed mostly in green algae. In the Japanese tradition, macrophytic red algae such as Pyropia yezoensis and Gelidium crinale have been utilized as food and industrial materials. Researches on the utilization of unicellular red microalgae such as Cyanidioschyzon merolae and Porphyridium purpureum started only quite recently. Red algae have relatively large plastid genomes harboring more than 200 protein-coding genes that support the biosynthetic capacity of the plastid. Engineering the plastid genome is a unique potential of red microalgae. In addition, large-scale growth facilities of P. purpureum have been developed for industrial production of biofuels. C. merolae has been studied as a model alga for cell and molecular biological analyses with its completely determined genomes and transformation techniques. Its acidic and warm habitat makes it easy to grow this alga axenically in large scales. Its potential as a biofuel producer is recently documented under nitrogen-limited conditions. Metabolic pathways of the accumulation of starch and triacylglycerol and the enzymes involved therein are being elucidated. Engineering these regulatory mechanisms will open a possibility of exploiting the full capability of production of biofuel and high added-value oil. In the present review, we will describe the characteristics and potential of these algae as biotechnological seeds.

  8. Pearl millet genome sequence provides a resource to improve agronomic traits in arid environments

    USDA-ARS?s Scientific Manuscript database

    Pearl millet [Pennisetum glaucum (L.) R. Br., syn. Cenchrus americanus (L.) Morrone], is a staple food for over 90 million poor farmers in arid and semi-arid regions of sub-Saharan Africa and South Asia. We report the ~1.79 Gb genome sequence of reference genotype Tift 23D2B1-P1-P5, which contains a...

  9. Effects of cattle grazing, glyphosate, and prescribed burning on fountaingrass fuel loading in Hawai`i

    Treesearch

    J.M. Castillo; G. Enriques; M. Nakahara; D. Weise; L. Ford; R. Moraga; R. Vihnanek

    2007-01-01

    Crimson fountaingrass (Pennisetum setaceum) is a nonnative invasive grass that has occupied a significant portion of the western side of the island of Hawai`i. As a result, several fires in excess of 4,049 ha have occurred in the area over the past 20 y. We are studying the effectiveness of cattle grazing, aerial application of glyphosate herbicide, and prescribed...

  10. Evaluation of the mechanisms of intron loss and gain in the social amoebae Dictyostelium.

    PubMed

    Ma, Ming-Yue; Che, Xun-Ru; Porceddu, Andrea; Niu, Deng-Ke

    2015-12-18

    Spliceosomal introns are a common feature of eukaryotic genomes. To approach a comprehensive understanding of intron evolution on Earth, studies should look beyond repeatedly studied groups such as animals, plants, and fungi. The slime mold Dictyostelium belongs to a supergroup of eukaryotes not covered in previous studies. We found 441 precise intron losses in Dictyostelium discoideum and 202 precise intron losses in Dictyostelium purpureum. Consistent with these observations, Dictyostelium discoideum was found to have significantly more copies of reverse transcriptase genes than Dictyostelium purpureum. We also found that the lost introns are significantly further from the 5' end of genes than the conserved introns. Adjacent introns were prone to be lost simultaneously in Dictyostelium discoideum. In both Dictyostelium species, the exonic sequences flanking lost introns were found to have a significantly higher GC content than those flanking conserved introns. Together, these observations support a reverse-transcription model of intron loss in which intron losses were caused by gene conversion between genomic DNA and cDNA reverse transcribed from mature mRNA. We also identified two imprecise intron losses in Dictyostelium discoideum that may have resulted from genomic deletions. Ninety-eight putative intron gains were also observed. Consistent with previous studies of other lineages, the source sequences were found in only a small number of cases, with only two instances of intron gain identified in Dictyostelium discoideum. Although they diverged very early from animals and fungi, Dictyostelium species have similar mechanisms of intron loss.

  11. Seasonal variations in the availability of fodder resources and practices of dairy cattle feeding among the smallholder farmers in Western Usambara Highlands, Tanzania.

    PubMed

    Maleko, David; Ng, Wai-Tim; Msalya, George; Mwilawa, Angello; Pasape, Liliane; Mtei, Kelvin

    2018-05-08

    The aim of this study was to assess the seasonal effects on quantity and quality of fodder resources and associated utilization practices among smallholder dairy farmers in Western Usambara Highlands (WUHs) in Tanzania. The WUHs are among the major milk producing areas under smallholder dairy farming systems (SDFS) in Tanzania. Dry season fodder scarcity is a widespread problem affecting the East African SDFS and has been shown to contribute to over 40% reduction in milk yield. There is limited information with regard to seasonal fodder fluctuation and its effects on productivity of dairy cows in different landscape levels of Tanzania. Field and household surveys were conducted in 150 dairy cattle farming households from five villages in three wards located in WUHs. Survey data were analyzed using IBM SPSS version 21. In addition, remote sensing techniques were employed on gap-filled and smoothed Landsat data to generate land cover maps and bimonthly normalized difference vegetation index-time series for the 2009-2016. SDFS landscape was highly heterogeneous typified by crops, bushes, and forests. On average, the household landholding was 1.3 ha, while herd size was three cattle. About 87% of household land was devoted to crop growing with limited pasture along the farm margins and contour strips. Fodder scarcity was the major challenge during the dry season (July to October) as indicated by 87% of the respondents. On-farm fodder resources contributed most of the cattle diet (73%) while rangeland, forest, and purchased feed provided small amount. Natural pasture and napier grass (Pennisetum purpureum) were the most important feeds in wet season while maize stover was most significant during the dry season. Maize stover was profusely stored for dry season feeding and neither silage nor hay making was practiced. The nutritional values of the fibrous feeds declined during the dry season, whereby the metabolizable energy and crude protein contents were 6.0 MJ/kg and

  12. Chemical composition and some biological activities of the essential oils from basil Ocimum different cultivars.

    PubMed

    Avetisyan, Arpi; Markosian, Anahit; Petrosyan, Margarit; Sahakyan, Naira; Babayan, Anush; Aloyan, Samvel; Trchounian, Armen

    2017-01-19

    The plants belonging to the Ocimum genus of the Lamiaceae family are considered to be a rich source of essential oils which have expressed biological activity and use in different area of human activity. There is a great variety of chemotypes within the same basil species. Essential oils from three different cultivars of basil, O. basilicum var. purpureum, O. basilicum var. thyrsiflora, and O. citriodorum Vis. were the subjects of our investigations. The oils were obtained by steam distillation in a Clevenger-type apparatus. The gas chromatography mass selective analysis was used to determine their chemical composition. The antioxidant activities of these essential oils were measured using 1,1-diphenyl-2-picrylhydrazyl assays; the tyrosinase inhibition abilities of the given group of oils were also assessed spectophotometrically, and the antimicrobial activity of the essential oils was determined by the agar diffusion method, minimal inhibitory concentrations were expressed. According to the results, the qualitative and quantitative composition of essential oils was quite different: O. basilicum var. purpureum essential oil contained 57.3% methyl-chavicol (estragol); O. basilicum var. thyrsiflora oil had 68.0% linalool. The main constituents of O. citriodorum oil were nerol (23.0%) and citral (20.7%). The highest antioxidant activity was demonstrated by O. basilicum var. thyrsiflora essential oil. This oil has also exhibited the highest tyrosinase inhibition level, whereas the oil from O. citriodorum cultivar demonstrated the highest antimicrobial activity. The results obtained indicate that these essential oils have antioxidant, antibacterial and antifungal activity and can be used as natural antioxidant and antimicrobial agents in medicine, food industry and cosmetics.

  13. Glyphosate and dicamba herbicide tank mixture effects on native plant and non-genetically engineered soybean seedlings.

    PubMed

    Olszyk, David; Pfleeger, Thomas; Lee, E Henry; Plocher, Milton

    2015-07-01

    Crops engineered to contain genes for tolerance to multiple herbicides may be treated with several herbicides to manage weeds resistant to each herbicide. Thus, nearby non-target plants may be subjected to increased exposure to several herbicides used in combination. Of particular concern are native plants, as well as adjacent crops which have not been genetically engineered for tolerance to herbicides. We evaluated responses of seven species of native plants grown in a greenhouse and treated less than field application rates of glyphosate and/or dicamba: Andropogon gerardii, Asclepias syriaca, Eutrochium purpureum, Oenothera biennis, Polyganum lapathifolium, Solidago canadensis and Tridens flavus, and non-herbicide resistant soybean (Glycine max, Oregon line M4). Herbicide concentrations were 0.03 or 0.1 × field application rates of 1122 g ha(-1) active ingredient (a.i) (831 g ha(-1) acid glyphosate) for glyphosate and 562 g ha(-1) a.i. for dicamba. In general, plant growth responses to combinations of glyphosate and dicamba were less than the sum of growth responses to the individual herbicides (i.e., antagonistic effect), primarily when one or both herbicides alone caused a large reduction in growth. E. purpureum, P. lapathifolium and S. canadensis were the most sensitive species to both herbicides, while A. gerardii was the most tolerant, with no response to either herbicide. The combinations of herbicides resulted in responses most similar to that from dicamba alone for G. max and from glyphosate alone for T. flavus. The results of this study indicated the need for more data such as effects on native plants in the field to assess risks to non-target plants from combinations of herbicides.

  14. Structure determination and total synthesis of a novel antibacterial substance, AB0022A, produced by a cellular slime mold.

    PubMed

    Sawada, T; Aono, M; Asakawa, S; Ito, A; Awano, K

    2000-09-01

    A novel antibacterial substance, AB0022A, was isolated from the cellular slime mold Dictyostelium purpureum K1001. It inhibited the growth of Gram-positive bacteria, and its MICs ranged from 0.39 to 50 microg/ml. Because AB0022A was a highly substituted aromatic compound, we could not determine its structure based on only its physico-chemical and spectral data. We therefore used a dehalogenated derivative from AB0022A and deduced that its structure was 1,9-dihydroxy-3,7-dimethoxy-2-hexanoyl-4,6,8-trichlorodibenzofuran . To confirm this structure, we synthesized the compound having the deduced structure. The synthetic compound was identical to naturally occurring AB0022A.

  15. Polyploidy and interspecific hybridization in Cynodon, Paspalum, Pennisetum, and Zoysia

    USDA-ARS?s Scientific Manuscript database

    There are many examples of agronomically or economically important characteristics in wild species, such as disease tolerance or quality, that are difficult to incorporate into related cultivated species due to differences in ploidy levels. Sterility, or at least reduced fertility, is common when w...

  16. The utility of covariance of combining ability in plant breeding.

    PubMed

    Arunachalam, V

    1976-11-01

    The definition of covariances of half- and full sibs, and hence that of variances of general and specific combining ability with regard to a quantitative character, is extended to take into account the respective covariances between a pair of characters. The interpretation of the dispersion and correlation matrices of general and specific combining ability is discussed by considering a set of single, three- and four-way crosses, made using diallel and line × tester mating systems in Pennisetum typhoides. The general implications of the concept of covariance of combining ability in plant breeding are discussed.

  17. Dominant gene for rust resistance in pearl millet

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hanna, W.W.; Wells, H.D.; Burton, G.W.

    1985-01-01

    Rust (Puccinia substriata var. indica) resistance was discovered in three Pennisetum americanum (L.) Leeke subspecies monodii (Maire) Brunken accessions from Senegal. Resistant plant were free of rust, although the bottom one or two leaves of some plants did develop a brown discoloration without pustules. Resistance was controlled by a dominant gene assigned the gene symbol Rr1. Backcrossing has been effective in transferring resistance from the wild grassy, monodii to cultivated pearl millet. The Rr1 gene should be useful in the production of rust resistant pearl millet hybrids and cultivars. 6 references, 1 table.

  18. Biological control of tanoak and bay laurel resprouts using the fungus, Chondrostereum purpureum

    Treesearch

    Marianne Elliott; Gary Chastagner; Simon Shamoun; Grace Sumampong; Ellen Goheen; Alan Kanaskie

    2013-01-01

    In southwest Oregon, an aggressive program of cutting and burning host plants in an effort toeradicate Phytophthora ramorum was initiated. It was soon apparent that tanoak (Notholithocarpus densiflorus (Hook.& Arn.) Manos, Cannon& S.H. Oh) resprouts were highly susceptible to P. ramorum and...

  19. A comparative genomics strategy for targeted discovery of single-nucleotide polymorphisms and conserved-noncoding sequences in orphan crops.

    PubMed

    Feltus, F A; Singh, H P; Lohithaswa, H C; Schulze, S R; Silva, T D; Paterson, A H

    2006-04-01

    Completed genome sequences provide templates for the design of genome analysis tools in orphan species lacking sequence information. To demonstrate this principle, we designed 384 PCR primer pairs to conserved exonic regions flanking introns, using Sorghum/Pennisetum expressed sequence tag alignments to the Oryza genome. Conserved-intron scanning primers (CISPs) amplified single-copy loci at 37% to 80% success rates in taxa that sample much of the approximately 50-million years of Poaceae divergence. While the conserved nature of exons fostered cross-taxon amplification, the lesser evolutionary constraints on introns enhanced single-nucleotide polymorphism detection. For example, in eight rice (Oryza sativa) genotypes, polymorphism averaged 12.1 per kb in introns but only 3.6 per kb in exons. Curiously, among 124 CISPs evaluated across Oryza, Sorghum, Pennisetum, Cynodon, Eragrostis, Zea, Triticum, and Hordeum, 23 (18.5%) seemed to be subject to rigid intron size constraints that were independent of per-nucleotide DNA sequence variation. Furthermore, we identified 487 conserved-noncoding sequence motifs in 129 CISP loci. A large CISP set (6,062 primer pairs, amplifying introns from 1,676 genes) designed using an automated pipeline showed generally higher abundance in recombinogenic than in nonrecombinogenic regions of the rice genome, thus providing relatively even distribution along genetic maps. CISPs are an effective means to explore poorly characterized genomes for both DNA polymorphism and noncoding sequence conservation on a genome-wide or candidate gene basis, and also provide anchor points for comparative genomics across a diverse range of species.

  20. A Comparative Genomics Strategy for Targeted Discovery of Single-Nucleotide Polymorphisms and Conserved-Noncoding Sequences in Orphan Crops1[W

    PubMed Central

    Feltus, F.A.; Singh, H.P.; Lohithaswa, H.C.; Schulze, S.R.; Silva, T.D.; Paterson, A.H.

    2006-01-01

    Completed genome sequences provide templates for the design of genome analysis tools in orphan species lacking sequence information. To demonstrate this principle, we designed 384 PCR primer pairs to conserved exonic regions flanking introns, using Sorghum/Pennisetum expressed sequence tag alignments to the Oryza genome. Conserved-intron scanning primers (CISPs) amplified single-copy loci at 37% to 80% success rates in taxa that sample much of the approximately 50-million years of Poaceae divergence. While the conserved nature of exons fostered cross-taxon amplification, the lesser evolutionary constraints on introns enhanced single-nucleotide polymorphism detection. For example, in eight rice (Oryza sativa) genotypes, polymorphism averaged 12.1 per kb in introns but only 3.6 per kb in exons. Curiously, among 124 CISPs evaluated across Oryza, Sorghum, Pennisetum, Cynodon, Eragrostis, Zea, Triticum, and Hordeum, 23 (18.5%) seemed to be subject to rigid intron size constraints that were independent of per-nucleotide DNA sequence variation. Furthermore, we identified 487 conserved-noncoding sequence motifs in 129 CISP loci. A large CISP set (6,062 primer pairs, amplifying introns from 1,676 genes) designed using an automated pipeline showed generally higher abundance in recombinogenic than in nonrecombinogenic regions of the rice genome, thus providing relatively even distribution along genetic maps. CISPs are an effective means to explore poorly characterized genomes for both DNA polymorphism and noncoding sequence conservation on a genome-wide or candidate gene basis, and also provide anchor points for comparative genomics across a diverse range of species. PMID:16607031

  1. A parthenogenesis gene of apomict origin elicits embryo formation from unfertilized eggs in a sexual plant

    PubMed Central

    Conner, Joann A.; Mookkan, Muruganantham; Huo, Heqiang; Chae, Keun; Ozias-Akins, Peggy

    2015-01-01

    Apomixis is a naturally occurring mode of asexual reproduction in flowering plants that results in seed formation without the involvement of meiosis or fertilization of the egg. Seeds formed on an apomictic plant contain offspring genetically identical to the maternal plant. Apomixis has significant potential for preserving hybrid vigor from one generation to the next in highly productive crop plant genotypes. Apomictic Pennisetum/Cenchrus species, members of the Poaceae (grass) family, reproduce by apospory. Apospory is characterized by apomeiosis, the formation of unreduced embryo sacs derived from nucellar cells of the ovary and, by parthenogenesis, the development of the unreduced egg into an embryo without fertilization. In Pennisetum squamulatum (L.) R.Br., apospory segregates as a single dominant locus, the apospory-specific genomic region (ASGR). In this study, we demonstrate that the PsASGR-BABY BOOM-like (PsASGR-BBML) gene is expressed in egg cells before fertilization and can induce parthenogenesis and the production of haploid offspring in transgenic sexual pearl millet. A reduction of PsASGR-BBML expression in apomictic F1 RNAi transgenic plants results in fewer visible parthenogenetic embryos and a reduction of embryo cell number compared with controls. Our results endorse a key role for PsASGR-BBML in parthenogenesis and a newly discovered role for a member of the BBM-like clade of APETALA 2 transcription factors. Induction of parthenogenesis by PsASGR-BBML will be valuable for installing parthenogenesis to synthesize apomixis in crops and will have further application for haploid induction to rapidly obtain homozygous lines for breeding. PMID:26305939

  2. A parthenogenesis gene of apomict origin elicits embryo formation from unfertilized eggs in a sexual plant.

    PubMed

    Conner, Joann A; Mookkan, Muruganantham; Huo, Heqiang; Chae, Keun; Ozias-Akins, Peggy

    2015-09-08

    Apomixis is a naturally occurring mode of asexual reproduction in flowering plants that results in seed formation without the involvement of meiosis or fertilization of the egg. Seeds formed on an apomictic plant contain offspring genetically identical to the maternal plant. Apomixis has significant potential for preserving hybrid vigor from one generation to the next in highly productive crop plant genotypes. Apomictic Pennisetum/Cenchrus species, members of the Poaceae (grass) family, reproduce by apospory. Apospory is characterized by apomeiosis, the formation of unreduced embryo sacs derived from nucellar cells of the ovary and, by parthenogenesis, the development of the unreduced egg into an embryo without fertilization. In Pennisetum squamulatum (L.) R.Br., apospory segregates as a single dominant locus, the apospory-specific genomic region (ASGR). In this study, we demonstrate that the PsASGR-BABY BOOM-like (PsASGR-BBML) gene is expressed in egg cells before fertilization and can induce parthenogenesis and the production of haploid offspring in transgenic sexual pearl millet. A reduction of PsASGR-BBML expression in apomictic F1 RNAi transgenic plants results in fewer visible parthenogenetic embryos and a reduction of embryo cell number compared with controls. Our results endorse a key role for PsASGR-BBML in parthenogenesis and a newly discovered role for a member of the BBM-like clade of APETALA 2 transcription factors. Induction of parthenogenesis by PsASGR-BBML will be valuable for installing parthenogenesis to synthesize apomixis in crops and will have further application for haploid induction to rapidly obtain homozygous lines for breeding.

  3. WITHDRAWN: Bioaugmentation strategies to improve cellulolytic and hydrogen-producing characteristics of CSTR intermittent fed with vegetable kitchen waste and napiergrass.

    PubMed

    Kuo, Wen-Chien; Chao, Yu-Chieh; Wang, Ying-Chi; Hsieh, Ping-Heng; Cheng, Sheng-Shung

    2012-11-15

    This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at http://www.elsevier.com/locate/withdrawalpolicy. Copyright © 2012. Published by Elsevier Ltd.. All rights reserved.

  4. Genetic heterogeneity in wild isolates of cellular slime mold social groups.

    PubMed

    Sathe, Santosh; Kaushik, Sonia; Lalremruata, Albert; Aggarwal, Ramesh K; Cavender, James C; Nanjundiah, Vidyanand

    2010-07-01

    This study addresses the issues of spatial distribution, dispersal, and genetic heterogeneity in social groups of the cellular slime molds (CSMs). The CSMs are soil amoebae with an unusual life cycle that consists of alternating solitary and social phases. Because the social phase involves division of labor with what appears to be an extreme form of "altruism", the CSMs raise interesting evolutionary questions regarding the origin and maintenance of sociality. Knowledge of the genetic structure of social groups in the wild is necessary for answering these questions. We confirm that CSMs are widespread in undisturbed forest soil from South India. They are dispersed over long distances via the dung of a variety of large mammals. Consistent with this mode of dispersal, most social groups in the two species examined for detailed study, Dictyostelium giganteum and Dictyostelium purpureum, are multi-clonal.

  5. [A comparative study on seed germination of 15 grass species in Keeqin Sandyland].

    PubMed

    Liu, Zhimin; Li, Xuehua; Li, Rongping; Jiang, Deming; Cao, Chengyou

    2003-09-01

    A laboratory study was made on the germination characteristics of freshly-collected seeds of grass species at the Wulanaodu area of Keeqin Sandyland in Eastern Inner-Mongolia. Of the 15 species examined, 8 species including Clinelymus dahuricus, Cleistogenes squarrosa, Pappophorum boreale, Spodiopogon sibiricus, Phragmites communis, Chloris virgata, Arundinella hirta, Pennisetum alopecuroides had a germination rate of over 80%, but 4 species including Echinochloa hispidula, Hemarthria compressa, Tragus berteronianus and Setaria viridis had a value of less than 10%. Spodiopogon sibiricus, Eragrostis pilosa, Phragmites communis, Chloris virgata, Clinelymus dahuricus, Pappophorum boreale, Digitaria cilliaris and Cleistogenes squrrosa began to germinate within 1-3 days after the test began, while Setaria viridis, Tragus berteronianus and Hemarthria compressa failed to germinate in a period of more than 10 days. For the species such as Digitaria cilliaris, Echinochloa hispidula, Phragmites communis, Eragrostis pilosa and Spodiopogon sibiricus, their germination period was less than 10 days, while Clinelymus dahuricus and Pappophorum boreale had a germination period of more than 20 days. The days required for half the final germination rate to be reached were: 2 days for Chloris virgata, 3 days for Phragmites communis, 4 days for Spodiopogon sibiricus, 5 days for Clinelymus dahuricus and Cleistogenes squarrosa, 7 days for Arundinella hirta and Pappophorum boreale, and 10 days for Pennisetum alopecuriodes. Compared with the Sheffield region in Britain, the Wulanaodu area of Kerqin Sandyland had a higher proportion of annul grasses with a low germination rate and a longer germination period, and the perennial grasses at the Wulanaodu area had an approximately same germination rate, but a longer germination period. During germination, ruderals showed the potential for risk-sharring, and thus, they had a relatively higher disturbance-resistance capacity.

  6. Distribution of larval and pupal stages of Simulium (Diptera: Simuliidae) flies in the Nilgiris hills of Tamil Nadu.

    PubMed

    Soundararajan, C; Nagarajan, K; Arul Prakash, M

    2017-09-01

    Endemicity of onchocerciasis (river blindness) in humans is linked to the location of Simulium spp. (black fly). The distribution of immature stages of Simulium in Sholur, Pykara, Gudalur, Coonoor and Kotagiri streams of the Nilgiris hills of Tamil Nadu was investigated during the months of May and July 2012. Out of these five streams, only Sholur was infested with larval and pupal stages of Simulium spp. Out of six plants collected from various water bodies, larval and pupal stages were found on the leaves and stems of an aquatic plant Nasturtium officinale and on the roots and leaves of Pennisetum glandulosum. The stages of Simulium were observed only during the summer month of May.

  7. Buffelgrass-Integrated modeling of an invasive plant

    USGS Publications Warehouse

    Holcombe, Tracy R.

    2011-01-01

    Buffelgrass (Pennisetum ciliare) poses a problem in the deserts of the United States, growing in dense stands and introducing a wildfire risk in an ecosystem not adapted to fire. The Invasive Species Science Branch of the Fort Collins Science Center has worked with many partners to develop a decision support model and a data management system to address the problem. The decision support model evaluates potential strategies for resource use and allocation. The data management system is a portal where users can submit, view, and download buffelgrass data. These tools provide a case study showcasing how the FORT is working to address the urgent issue of invasive species in the United States.

  8. Biological evaluation of pearl millet protein: effect of different treatments and storage.

    PubMed

    Kapoor, R; Kapoor, A C

    1990-07-01

    Whole grain flour of one variety (HC-4) of pearl millet (Pennisetum americanum L. Leeke) after giving different treatments (defatting, butylated hydroxyanisole, ascorbic acid and thermal) was stored in earthen pots at prevailing room temperature (28-34 degrees C) and relative humidity (70-80%) for 30 days. The flour samples were evaluated for protein quality using rats. Storage of flour for 30 days markedly reduced the protein quality. The values of protein efficiency ratio, true digestibility, biological value, net protein retention and net protein utilisation were significantly (P less than 0.05) higher in fresh and treated flour than untreated flour. Among treated flours, defatted flour showed best growth followed by butylated hydroxyanisole, thermal and ascorbic acid treated flour.

  9. Phylogeny and photosynthesis of the grass tribe Paniceae.

    PubMed

    Washburn, Jacob D; Schnable, James C; Davidse, Gerrit; Pires, J Chris

    2015-09-01

    The grass tribe Paniceae includes important food, forage, and bioenergy crops such as switchgrass, napiergrass, various millet species, and economically important weeds. Paniceae are also valuable for answering scientific and evolutionary questions about C4 photosynthetic evolution, drought tolerance, and spikelet variation. However, the phylogeny of the tribe remains incompletely resolved. Forty-five taxa were selected from across the tribe Paniceae and outgroups for genome survey sequencing (GSS). These data were used to build a phylogenetic tree of the Paniceae based on 102 markers (78 chloroplast, 22 mitochondrial, 2 nrDNA). Ancestral state reconstruction analyses were also performed within the Paniceae using both the traditional and two subtype classification systems to test hypotheses of C4 subtype evolution. The phylogenetic tree resolves many areas of the Paniceae with high support and provides insight into the origin and number of C4 evolution events within the tribe. The recovered phylogeny and ancestral state reconstructions support between four and seven independent origins of C4 photosynthesis within the tribe and indicate which species are potentially the closest C3 sister taxa of each of these events. Although the sequence of evolutionary events that produced multiple C4 subtypes within the Paniceae remains undetermined, the results presented here are consistent with only a subset of currently proposed models. The species used in this study constitute a panel of C3 and C4 grasses that are suitable for further studies on C4 photosynthesis, bioenergy, food and forage crops, and various developmental features of the Paniceae. © 2015 Botanical Society of America.

  10. Chemical, green and organic manure effects on chemical properties on a savannah oxisol and on corn under conventional tillage and no-tillage

    NASA Astrophysics Data System (ADS)

    Mannigel, Anny R.; Alves, Marlene C.; Valério Filho, Walter V.

    2015-04-01

    Modern agriculture, in general, has always been based on the concept that natural resources are endless; however, this concept is changing. Concern for the environment is increasingly becoming part of farming practices, either by the awareness of society, or because the high cost of fertilizers or even the exhaustion of soils. The objective of this research was to evaluate the effects of the green manure and mineral fertilizer and/or organic manure and, on the chemical properties of an Oxisol, on "Savannah" (cerrado) area in Mato Grosso do Sul-Brazil, cultivated with corn (Zea mays L.) on the following management conditions: no-tillage and conventional tillage, on area previously under pasture (Brachiaria decumbens). The experimental design was a randomized blocks and the tested treatments were: control (without organic manure or chemical fertilizer); chemical fertilizer, as recommended for the culture and based on the chemical soil analysis; organic manure (cow manure); organic manure + half of the mineral fertilizer recommended rate; and the green manure Crotalaria juncea and Pennisetum americanum. The chemical analyses were the soil chemical analysis to the intent of soil fertility. Corn yield was evaluated. The collect of soil samples were realized in depths of 0.00-0.05 m and 0.05-0.10 m and 0.10-0.20 m. The organic manure and the organic manure + half of the mineral recommended rate increased P, Ca, Mg, K and Organic Matter in the first depth (0.00 - 0.05 m). These treatments also increased K and Mg at the second depth analyzed (0.05 - 0.10 m) and K in the depth from 0.10 - 0.20 m. Under conventional tillage management presents better crop results with an average grain yield of 3649 kg ha-1 versus 2374 kg ha-1 obtained under no-tillage. The use of chemical fertilizer, organic manure + half of the mineral recommended rate, Crotalaria juncea, organic manure and Pennisetum americanum increased corn yield by 84, 79, 58, 44 and 41 %, respectively.

  11. Synergistic effects of Arbuscular mycorrhizal fungi and plant growth promoting rhizobacteria in bioremediation of iron contaminated soils.

    PubMed

    Mishra, Vartika; Gupta, Antriksh; Kaur, Parvinder; Singh, Simranjeet; Singh, Nasib; Gehlot, Praveen; Singh, Joginder

    2016-01-01

    Three Arbuscular mycorrhizal fungi (AMF) from Glomus, Acaulospora and Scutellospora, and four plant growth promoting rhizobacteria (PGPR) isolates related to genera Streptomyces, Azotobacter, Pseudomonas and Paenibacillus were found to be effective in phytoremediation of Fe(3+) contaminated soil where Pennisetum glaucum and Sorghum bicolor were growing as host plants. Co-inoculation of AMF and PGPR showed better results in comparison to either, AMF and PGPR under pot conditions. Both AMF and PGPR were able to produce siderophores. AMF and PGPR associated to P. glaucum and S. bicolor plants increased the extent of iron absorption. AMF and PGPR combination exhibited superior (p < 0.01) phytoremediation efficiency with P. glaucum compared to S. bicolor. These findings warrant further investigations of these synergistic interactions and large-scale in situ studies for bioremediation of iron-contaminated soils.

  12. A new source of cytoplasmic male sterility in pearl millet: RFLP analysis of mitochondrial DNA.

    PubMed

    Sujata, V; Sivaramakrishnan, S; Rai, K N; Seetha, K

    1994-06-01

    A new source of cytoplasmic male sterility (cms) in pearl millet (Pennisetum glaucum (L.) R.Br.) derived from a half-sib progeny of the Early Gene Pool (EGP 261) and used in a male-sterile line, ICMA 90111, was compared with other known cms sources for RFLP of mitochondrial (mt) DNA. Southern blot hybridization of mtDNA from ICMA 90111 digested with several restriction enzymes and probed with homologous mtDNA clones from pearl millet and heterologous gene clones from maize and wheat revealed the RFLP patterns of ICMA 90111 distinct from others studied so far. The dendrogram of male-sterile lines constructed from the Southern blot hybridization patterns indicated that ICMA 90111 represents a separate group. Our results suggest that this source of cms is unique in several respects.

  13. New combinations for Pacific endemic species: Marquesan Poaceae, and Micronesian Myrtaceae

    PubMed Central

    Tornabene, Michael W.; Wagner, Warren L.

    2013-01-01

    Abstract As part of the preparation for a comprehensive online flora of Pacific oceanic islands, numerous taxonomic changes have been necessary, primarily due to a new wealth of global molecular phylogenetic studies on genera that include Pacific islands species. In order to compile an accurate checklist of the Pacific island flora with up-to-date taxonomies, we are moving several species to their currently accepted genera. Two Marquesan Pennisetum Rich. are transferred to Cenchrus L. with the new combinations Cenchrus articularis (Trin.) M. Tornabene & W.L. Wagner, and Cenchrus henryanus (F. Br.) M. Tornabene & W.L. Wagner. A key to Marquesas Cenchrus is also provided to differentiate the two species. Additionally, one species of Eugenia L. is transferred to Syzygium Gaertn. with the new combination Syzygium stelechanthoides (Kaneh.) M. Tornabene & W.L. Wagner in accord with the aforementioned studies. PMID:24399889

  14. New combinations for Pacific endemic species: Marquesan Poaceae, and Micronesian Myrtaceae.

    PubMed

    Tornabene, Michael W; Wagner, Warren L

    2013-01-01

    As part of the preparation for a comprehensive online flora of Pacific oceanic islands, numerous taxonomic changes have been necessary, primarily due to a new wealth of global molecular phylogenetic studies on genera that include Pacific islands species. In order to compile an accurate checklist of the Pacific island flora with up-to-date taxonomies, we are moving several species to their currently accepted genera. Two Marquesan Pennisetum Rich. are transferred to Cenchrus L. with the new combinations Cenchrus articularis (Trin.) M. Tornabene & W.L. Wagner, and Cenchrus henryanus (F. Br.) M. Tornabene & W.L. Wagner. A key to Marquesas Cenchrus is also provided to differentiate the two species. Additionally, one species of Eugenia L. is transferred to Syzygium Gaertn. with the new combination Syzygium stelechanthoides (Kaneh.) M. Tornabene & W.L. Wagner in accord with the aforementioned studies.

  15. Analysis of horizontal genetic transfer in red algae in the post-genomics age

    PubMed Central

    Chan, Cheong Xin; Bhattacharya, Debashish

    2013-01-01

    The recently published genome of the unicellular red alga Porphyridium purpureum revealed a gene-rich, intron-poor species, which is surprising for a free-living mesophile. Of the 8,355 predicted protein-coding regions, up to 773 (9.3%) were implicated in horizontal genetic transfer (HGT) events involving other prokaryote and eukaryote lineages. A much smaller number, up to 174 (2.1%) showed unambiguous evidence of vertical inheritance. Together with other red algal genomes, nearly all published in 2013, these data provide an excellent platform for studying diverse aspects of algal biology and evolution. This novel information will help investigators test existing hypotheses about the impact of endosymbiosis and HGT on algal evolution and enable comparative analysis within a more-refined, hypothesis-driven framework that extends beyond HGT. Here we explore the impacts of this infusion of red algal genome data on addressing questions regarding the complex nature of algal evolution and highlight the need for scalable phylogenomic approaches to handle the forthcoming deluge of sequence information. PMID:24475368

  16. Impact of mine waste dumps on growth and biomass of economically important crops.

    PubMed

    Mathiyazhagan, Narayanan; Natarajan, Devarajan

    2012-11-01

    The present study aimed to investigate the effect of magnesite and bauxite waste dumps on growth and biochemical parameters of some edible and economically important plants such as Vigna radiata, V. mungo, V. unguiculata, Eleusine coracana, Cajanus cajan, Pennisetum glaucum, Macrotyloma uniflorum, Oryza sativa, Sorghum bicolour, Sesamum indicum, Ricinus communis, Brassica juncea, Gossypium hirsutum and Jatropha curcas. The growth rate of all the crops was observed in the range of 75 to 100% in magnesite and 15 to 100% in bauxite mine soil. The moisture content of roots and shoots of all the crops were in the range of 24 to 77, 20 to 88% and 42 to 87, 59 to 88% respectively. The height of the crops was in the range of 2.6 to 48 cm in magnesite soil and 3 to 33 cm in bauxite soil. Thus the study shows that both mine soils reflects some physical and biomolecule impact on selected crops.

  17. Winery wastewater inhibits seed germination and vegetative growth of common crop species.

    PubMed

    Mosse, Kim P M; Patti, Antonio F; Christen, Evan W; Cavagnaro, Timothy R

    2010-08-15

    The ability to reuse winery wastewater would be of significant benefit to the wine industry, as it could potentially be a cost-effective method of wastewater management, whilst at the same time providing a valuable water resource. This study investigated the effects of different dilutions of a semi-synthetic winery wastewater on the growth and germination of four common crop species in a glasshouse study; barley (Hordeum vulgare), millet (Pennisetum glaucum), lucerne (Medicago sativa) and phalaris (Phalaris aquatica). The wastewater caused a significant delay in the germination of lucerne, millet and phalaris, although overall germination percentage of all species was not affected. Vegetative growth was significantly reduced in all species, with millet being the most severely affected. The germination index of barley correlated very highly (r(2)=0.99) with barley biomass, indicating that barley seed germination bioassays are highly relevant to plant growth, and therefore may be of use as a bioassay for winery wastewater toxicity. Copyright 2010 Elsevier B.V. All rights reserved.

  18. A new species of Peltidium Philippi, 1839 (Crustacea, Copepoda, Harpacticoida) from the Pacific coast of Mexico

    PubMed Central

    Suárez-Morales, Eduardo; Jarquín-González, Jani

    2013-01-01

    Abstract During the analysis of phytal meiobenthic samples collected from a rocky-sandy beach in the state of Nayarit, in the Mexican Pacific, several specimens of harpacticoid copepods were obtained and taxonomically examined. These specimens were found to represent an undescribed species of the peltidiid genus Peltidium Philippi, 1839. The new species, Peltidium nayarit sp. n. is described herein. It resembles Peltidium nichollsi Geddes and Peltidium lerneri Geddes from Bahamas but also the widespread Peltidium speciosum Thompson & Scott and Peltidium purpureum Philippi. The new species from the Mexican Pacific differs from its known congeners by its possession of a unique combination of characters, including a modified pectinate seta on the antennary exopod, three terminal setae on the second endopodal segment of leg 1, third exopodal segment of leg 1 with three elements, inner terminal claw twice as long as outer claw, female fifth leg with 5 exopodal setae, exopodal setae I-III stout, spinulose and seta IV being as long as seta V. This is the second species of the family known to be distributed in the Eastern Tropical Pacific and in Mexico. Pending additional data, the distribution of this species appears to be restricted to this area of the Mexican Pacific. PMID:24003319

  19. Leveraging the rice genome sequence for monocot comparative and translational genomics.

    PubMed

    Lohithaswa, H C; Feltus, F A; Singh, H P; Bacon, C D; Bailey, C D; Paterson, A H

    2007-07-01

    Common genome anchor points across many taxa greatly facilitate translational and comparative genomics and will improve our understanding of the Tree of Life. To add to the repertoire of genomic tools applicable to the study of monocotyledonous plants in general, we aligned Allium and Musa ESTs to Oryza BAC sequences and identified candidate Allium-Oryza and Musa-Oryza conserved intron-scanning primers (CISPs). A random sampling of 96 CISP primer pairs, representing loci from 11 of the 12 chromosomes in rice, were tested on seven members of the order Poales and on representatives of the Arecales, Asparagales, and Zingiberales monocot orders. The single-copy amplification success rates of Allium (31.3%), Cynodon (31.4%), Hordeum (30.2%), Musa (37.5%), Oryza (61.5%), Pennisetum (33.3%), Sorghum (47.9%), Zea (33.3%), Triticum (30.2%), and representatives of the palm family (32.3%) suggest that subsets of these primers will provide DNA markers suitable for comparative and translational genomics in orphan crops, as well as for applications in conservation biology, ecology, invasion biology, population biology, systematic biology, and related fields.

  20. The correlation between cellulose allomorphs (I and II) and conversion after removal of hemicellulose and lignin of lignocellulose.

    PubMed

    Song, Yanliang; Zhang, Jingzhi; Zhang, Xu; Tan, Tianwei

    2015-10-01

    H2SO4, NaOH and H3PO4 were applied to decompose lignocellulose samples (giant reeds, pennisetum and cotton stalks) to investigate the correlation between cellulose allomorphs (cellulose I and II) and conversion of cellulose. The effect of removal of hemicellulose and lignin on the surface morphology, crystallinity index (CrI), cellulose allomorphs (cellulose I and II), and enzymatic hydrolysis under different pretreatments was also studied. CrI caused by H3PO4 pretreatment reached 11.19%, 24.93% and 8.15% for the three samples, respectively. Corn stalk showed highest conversion of cellulose among three samples, irrespective of the pretreatment used. This accounted for the widely use of corn stalk as the renewable crop substrate to synthesize biofuels like ethanol. CrI of cellulose I (CrI-I) negatively affects cellulose conversion but CrI of cellulose II (CrI-II) positively affects cellulose conversion. It contributes to make the strategy to transform cellulose I to cellulose II and enhancing enzymatic hydrolysis of lignocellulose. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Crop production and economic loss due to wind erosion in hot arid ecosystem of India

    NASA Astrophysics Data System (ADS)

    Santra, Priyabrata; Moharana, P. C.; Kumar, Mahesh; Soni, M. L.; Pandey, C. B.; Chaudhari, S. K.; Sikka, A. K.

    2017-10-01

    Wind erosion is a severe land degradation process in hot arid western India and affects the agricultural production system. It affects crop yield directly by damaging the crops through abrasion, burial, dust deposition etc. and indirectly by reducing soil fertility. In this study, an attempt was made to quantify the indirect impact of wind erosion process on crop production loss and associated economic loss in hot arid ecosystem of India. It has been observed that soil loss due to wind erosion varies from minimum 1.3 t ha-1 to maximum 83.3 t ha-1 as per the severity. Yield loss due to wind erosion was found maximum for groundnut (Arachis hypogea) (5-331 kg ha-1 yr-1), whereas minimum for moth bean (Vigna aconitifolia) (1-93 kg ha-1 yr-1). For pearl millet (Pennisetum glaucum), which covers a major portion of arable lands in western Rajasthan, the yield loss was found 3-195 kg ha-1 yr-1. Economic loss was found higher for groundnut and clusterbean (Cyamopsis tetragonoloba) than rest crops, which are about

  2. Gamma radiation effects on microbiological, physico-chemical and antioxidant properties of Tunisian millet (Pennisetum Glaucum L.R.Br.).

    PubMed

    Ben Mustapha, Maha; Bousselmi, Mehrez; Jerbi, Taïeb; Ben Bettaïeb, Nasreddine; Fattouch, Sami

    2014-07-01

    Hygienic quality of Tunisian pearl millet flour is always of major concern to consumers as well as all involved in the production, processing and distribution sectors. In the present study, the microbiological and biochemical properties of this food were examined following gamma-radiation. The D10-values for the Total Aerobic Plate Count, yeasts and moulds were respectively 1.5 and 3.7kGy. Furthermore, millet flour is commonly susceptible to mycotoxin contaminations, so the Ochratoxin A residues were also investigated; a reduction of 74% was observed with 10kGy. Moreover, the radiation process did not significantly alter fatty acids composition of the millet flour as obtained with Gas chromatography-flame ionisation detector technic. The peroxide value had increased from 26.16 to 34.43meqO2/kg with 3kGy. At 1kGy, we noticed an important loss of vitamin A of about 88.6%. In contrast, the total phenolic content, the ABTS-RSA and the DPPH-RSA of the radiated millet flour exhibited non-significant changes (p<0.05). Copyright © 2014 Elsevier Ltd. All rights reserved.

  3. Role of fire in the germination ecology of fountain grass (Pennisetum setaceum), an invasive African bunchgrass in Hawaii

    Treesearch

    Edith N. Adkins; Susan Cordell; Donald R. Drake

    2011-01-01

    Field and laboratory studies were carried out to test factors expected to be relevant for the germination of fountain grass: (1) light; (2) emergence of fountain grass seedlings from depths of 0, 2.5, and 5 cm; (3) fire passing over exposed and buried seeds; (4) laboratory heat treatment mimicking exposure to grass fire. Both fire in the field and heat applied in the...

  4. Energy Analysis and Environmental Impacts of Hybrid Giant Napier (Pennisetum Hydridum) Direct-fired Power Generation in South China

    NASA Astrophysics Data System (ADS)

    Liao, Yanfen; Fang, Hailin; Zhang, Hengjin; Yu, Zhaosheng; Liu, Zhichao; Ma, Xiaoqian

    2017-05-01

    To meet with the demand of energy conservation and emission reduction policies, the method of life cycle assessment (LCA) was used to assess the feasibility of Hybrid Giant Napier (HGN) direct-fired power generation in this study. The entire life cycle is consisted of five stages (cultivation and harvesting, transportation, drying and comminuting, direct-fired power generation, constructing and decommissioning of biomass power plant). Analytical results revealed that to generate 10000kWh electricity, 10.925 t of customized HGN fuel (moisture content: 30 wt%) and 6659.430 MJ of energy were required. The total environmental impact potential was 0.927 PET2010 (person equivalents, targeted, in 2010) and the global warming (GW), acidification (AC), and nutrient (NE) emissions were 339.235 kg CO2-eq, 22.033 kg SO2-eq, and 25.486 kg NOx-eq respectively. The effect of AC was the most serious among all calculated category impacts. The energy requirements and environmental impacts were found to be sensitive to single yield, average transport distance, cutting frequency, and moisture content. The results indicated that HGN direct-fired power generation accorded well with Chinese energy planning; in addition, HGN proved to be a promising contribution to reducing non-renewable energy consumption and had encouraging prospects as a renewable energy plant.

  5. Estimating millet production for famine early warning: An application of crop simulation modelling using satellite and ground-based data in Burkina Faso

    USGS Publications Warehouse

    Thornton, P. K.; Bowen, W. T.; Ravelo, A.C.; Wilkens, P. W.; Farmer, G.; Brock, J.; Brink, J. E.

    1997-01-01

    Early warning of impending poor crop harvests in highly variable environments can allow policy makers the time they need to take appropriate action to ameliorate the effects of regional food shortages on vulnerable rural and urban populations. Crop production estimates for the current season can be obtained using crop simulation models and remotely sensed estimates of rainfall in real time, embedded in a geographic information system that allows simple analysis of simulation results. A prototype yield estimation system was developed for the thirty provinces of Burkina Faso. It is based on CERES-Millet, a crop simulation model of the growth and development of millet (Pennisetum spp.). The prototype was used to estimate millet production in contrasting seasons and to derive production anomaly estimates for the 1986 season. Provincial yields simulated halfway through the growing season were generally within 15% of their final (end-of-season) values. Although more work is required to produce an operational early warning system of reasonable credibility, the methodology has considerable potential for providing timely estimates of regional production of the major food crops in countries of sub-Saharan Africa.

  6. Growth, Yield and Grain Nutritional Quality in Three Brazilian Pearl Millets (Pennisetum americanum L.) with African or Indian origins.

    PubMed

    Medici, Leonardo O; Gonçalves, Fabíola V; Fonseca, Marcos Paulo S DA; Gaziola, Salete A; Schmidt, Daiana; Azevedo, Ricardo A; Pimentel, Carlos

    2018-05-14

    In this study, we are presenting recommendations to the best agricultural use as well as for plant breeding of three millet cultivars namely ENA1 and ENA2, which have African origin, and BRS1501 originally from India. These cultivars were evaluated for growth, yield and grain quality traits. The morphological traits evaluated in this study indicated that the African genotypes ENA1 and ENA2 are better than the Indian genotype BRS1501 for no-till farming or to produce forage with 15% of crude protein at flowering and at harvest to produce stover (around 7% of crude protein content) for livestock feeding. The BRS1501 cultivar exhibited the highest values for total crude protein, albumins and prolamins, phytate and mineral contents in grains. ENA1 and ENA2 exhibited the highest values of globulin and glutelin contents. The electrophoretic patterns for storage proteins were similar across the three millets cultivars, except for a higher intensity of two glutelin bands with 21 and 24 kDa in BRS1501. Together, the results allow us to recommend BRS1501 for grain production and ENA1 and ENA2 for biomass production.

  7. Potential use of pearl millet (Pennisetum glaucum (L.) R. Br.) in Brazil: Food security, processing, health benefits and nutritional products.

    PubMed

    Dias-Martins, Amanda M; Pessanha, Kênia Letícia F; Pacheco, Sidney; Rodrigues, José Avelino S; Carvalho, Carlos Wanderlei Piler

    2018-07-01

    Climate change can cause an increase in arid soils, warmer weather, and reduce water availability, which in turn can directly affect food security. This increases food prices and reduces the availability of food. Therefore, knowledge concerning the nutritional and technological potential of non-traditional crops and their resistance to heat and drought is very interesting. Pearl millet is known to produce small nutritious cereal grains, which can endure both heat and dry conditions, and is one of the basic cereals of several African and Asian countries. Although this species has been cultivated in Brazil for at least 50 years it is only used as a cover crop and animal feed, but not for human consumption. Nonetheless, pearl millet grains have a high potential as food for humans because they are gluten-free, higher in dietary fiber content than rice, similar in lipid content to maize and higher content of essential amino acids (leucine, isoleucine and lysine) than other traditional cereals, such as wheat and rye. In addition, the crop is low cost and less susceptible to contamination by aflatoxins compared to corn, for example. Most grains, including pearl millet, can be milled, decorticated, germinated, fermented, cooked and extruded to obtain products such as flours, biscuits, snacks, pasta and non-dairy probiotic beverages. Pearl millet also has functional properties; it has a low glycemic index and therefore it can be used as an alternative food for weight control and to reduce the risk of chronic diseases, such as diabetes. Thus, this review intends to show the potential of pearl millet as an alternative food security crop, particularly in countries, like Brazil, where it is not commonly consumed. Also this review presents different processes and products that have been already reported in the literature in order to introduce the great potential of this important small grain to producers and consumers. Copyright © 2018 Elsevier Ltd. All rights reserved.

  8. Assessment of in situ and ex situ phytorestoration with grass mixtures in soils polluted with nickel, copper, and arsenic

    NASA Astrophysics Data System (ADS)

    Zacarías Salinas, Montserrat; Beltrán Villavicencio, Margarita; Bustillos, Luis Gilberto Torres; González Aragón, Abelardo

    This work shows a study of in situ and ex situ phytoextraction as a polishing step in the treatment of an industrial urban soil polluted with nickel, arsenic and copper. The soil was previously washed, and phytoextraction was performed by application of a mixture of grass (Festuca rubra, Cynodon dactylon, Lolium multiforum, Pennisetum). The soil had initial heavy metals concentrations of 131 ppm for Ni, 717 for As and 2734 for Cu (mg of metal/kg of dry soil). After seeding and emerging of grass, vegetal and soil samples were taken monthly during 4 months. Biomass generation, and concentration of Ni, As and Cu in vegetal tissue and soil were determined for every sample. Plants biomass growth in ex situ process was inhibited by 37% when compared with blank soil. Grass showed remarkable phytoextraction capability in situ, it produced 38 g of biomass every 15 days (wet weight) during a period of 3 months, but then declined in the fourth month. Concentrations of metals in grass biomass were up to 83 mg Ni/kg, 649 mg As/kg and 305 mg Cu/kg dry weight. Metal reduction of 49% for Ni, and 35% for Cu and As was observed at rhizospheric soil.

  9. Allelopathic Effects of Litter Axonopus compressus against Two Weedy Species and Its Persistence in Soil

    PubMed Central

    Samedani, B.; Juraimi, A. S.; Rafii, M. Y.; Anuar, A. R.; Sheikh Awadz, S. A.; Anwar, M. P.

    2013-01-01

    This study investigated the allelopathic effect of Axonopus compressus litter on Asystasia gangetica and Pennisetum polystachion. In experiment 1 the bioassays with 0, 10, 30, and 50 g L−1 of aqueous A. compressus litter leachate were conducted. Experiment 2 was carried out by incorporating 0, 10, 20, 30, 40, and 50 g L−1 of A. compressus litter leachate into soil. In experiment 3, the fate of A. compressus litter leachate phenolics in the soil was investigated. A. compressus leachates did not affect the germination percentage of A. gangetica and P. polystachion, but delayed germination of A. gangetica seeds and decreased seed germination time of P. polystachion. A. compressus litter leachates affected weeds hypocotyl length. Hypocotyl length reductions of 18 and 31% were observed at the highest concentration (50 g L−1) compared to the control in A. gangetica and P. polystachion, respectively. When concentration of A. compressus litter leachate-amended soil increased A. gangetica and P. polystachion seedling shoot length, root length, seedling weight and chlorophyll concentration were not affected. The 5-week decomposition study of A. compressus showed that the phenolic compounds in A. compressus litter abruptly decreased about 52% after two weeks and remained steady until the end of the incubation. PMID:24260020

  10. Ectopic expression of PgRab7 in rice plants (Oryza sativa L.) results in differential tolerance at the vegetative and seed setting stage during salinity and drought stress.

    PubMed

    Tripathy, Manas Kumar; Tiwari, Budhi Sagar; Reddy, Malireddy K; Deswal, Renu; Sopory, Sudhir K

    2017-01-01

    In this work, we have overexpressed a vesicle trafficking protein, Rab7, from a stress-tolerant plant, Pennisetum glaucum, in a high-yielding but stress-sensitive rice variety Pusa Basmati-1 (PB-1). The transgenic rice plants were tested for tolerance against salinity and drought stress. The transgenic plants showed considerable tolerance at the vegetative stage against both salinity (200 mM NaCl) and drought stress (up to 12 days after withdrawing water). The protection against salt and drought stress may be by regulating Na + ion homeostasis, as the transgenic plants showed altered expression of multiple transporter genes, including OsNHX1, OsNHX2, OsSOS1, OsVHA, and OsGLRs. In addition, decreased generation and maintenance of lesser reactive oxygen species (ROS), with maintenance of chloroplast grana and photosynthetic machinery was observed. When evaluated for reproductive growth, 89-96 % of seed setting was maintained in transgenic plants during drought stress; however, under salt stress, a 33-53 % decrease in seed setting was observed. These results indicate that PgRab7 overexpression in rice confers differential tolerance at the seed setting stage during salinity and drought stress and could be a favored target for raising drought-tolerant crops.

  11. The Empirical Distribution of Singletons for Geographic Samples of DNA Sequences.

    PubMed

    Cubry, Philippe; Vigouroux, Yves; François, Olivier

    2017-01-01

    Rare variants are important for drawing inference about past demographic events in a species history. A singleton is a rare variant for which genetic variation is carried by a unique chromosome in a sample. How singletons are distributed across geographic space provides a local measure of genetic diversity that can be measured at the individual level. Here, we define the empirical distribution of singletons in a sample of chromosomes as the proportion of the total number of singletons that each chromosome carries, and we present a theoretical background for studying this distribution. Next, we use computer simulations to evaluate the potential for the empirical distribution of singletons to provide a description of genetic diversity across geographic space. In a Bayesian framework, we show that the empirical distribution of singletons leads to accurate estimates of the geographic origin of range expansions. We apply the Bayesian approach to estimating the origin of the cultivated plant species Pennisetum glaucum [L.] R. Br . (pearl millet) in Africa, and find support for range expansion having started from Northern Mali. Overall, we report that the empirical distribution of singletons is a useful measure to analyze results of sequencing projects based on large scale sampling of individuals across geographic space.

  12. Micro-PIXE mapping of mineral distribution in mature grain of two pearl millet cultivars

    NASA Astrophysics Data System (ADS)

    Minnis-Ndimba, R.; Kruger, J.; Taylor, J. R. N.; Mtshali, C.; Pineda-Vargas, C. A.

    2015-11-01

    Micro-proton-induced X-ray emission (micro-PIXE) was used to map the distribution of several nutritionally important minerals found in the grain tissue of two cultivars of pearl millet (Pennisetum glaucum (L.) R. Br.). The distribution maps revealed that the predominant localisation of minerals was within the germ (consisting of the scutellum and embryo) and the outer grain layers (specifically the pericarp and aleurone); whilst the bulk of the endosperm tissue featured relatively low concentrations of the surveyed minerals. Within the germ, the scutellum was revealed as a major storage tissue for P and K, whilst Ca, Mn and Zn were more prominent within the embryo. Fe was revealed to have a distinctive distribution pattern, confined to the dorsal end of the scutellum; but was also highly concentrated in the outer grain layers. Interestingly, the hilar region was also revealed as a site of high accumulation of minerals, particularly for S, Ca, Mn, Fe and Zn, which may be part of a defensive strategy against infection or damage. Differences between the two cultivars, in terms of the bulk Fe and P content obtained via inductively coupled plasma optical emission spectrometry (ICP-OES), concurred with the average concentration data determined from the analysis of micro-PIXE spectra specifically extracted from the endosperm tissue.

  13. Identification and characterization of an anaerobic ethanol-producing cellulolytic bacterial consortium from Great Basin hot springs with agricultural residues and energy crops.

    PubMed

    Zhao, Chao; Deng, Yunjin; Wang, Xingna; Li, Qiuzhe; Huang, Yifan; Liu, Bin

    2014-09-01

    In order to obtain the cellulolytic bacterial consortia, sediments from Great Basin hot springs (Nevada, USA) were sampled and enriched with cellulosic biomass as the sole carbon source. The bacterial composition of the resulting anaerobic ethanol-producing celluloytic bacterial consortium, named SV79, was analyzed. With methods of the full-length 16S rRNA librarybased analysis and denaturing gradient gel electrophoresis, 21 bacteria belonging to eight genera were detected from this consortium. Clones with closest relation to the genera Acetivibrio, Clostridium, Cellulosilyticum, Ruminococcus, and Sporomusa were predominant. The cellulase activities and ethanol productions of consortium SV79 using different agricultural residues (sugarcane bagasse and spent mushroom substrate) and energy crops (Spartina anglica, Miscanthus floridulus, and Pennisetum sinese Roxb) were studied. During cultivation, consortium SV79 produced the maximum filter paper activity (FPase, 9.41 U/ml), carboxymethylcellulase activity (CMCase, 6.35 U/ml), and xylanase activity (4.28 U/ml) with sugarcane bagasse, spent mushroom substrate, and S. anglica, respectively. The ethanol production using M. floridulus as substrate was up to 2.63 mM ethanol/g using gas chromatography analysis. It has high potential to be a new candidate for producing ethanol with cellulosic biomass under anoxic conditions in natural environments.

  14. Determinants of the domiciliary density of Triatoma infestans, vector of Chagas disease.

    PubMed

    Gürtler, R E; Cecere, M C; Rubel, D N; Schweigmann, N J

    1992-01-01

    In two heavily infested rural villages of Santiago del Estero, Argentina, where no indoor-spraying with residual insecticides had ever been carried out by official control services, we studied the influence of roof and wall structure, domestic use of insecticide, family size and the number of domestic dogs, on the domiciliary density of Triatoma infestans (Klug). Bug density was significantly associated with (1) the interaction between insecticide use and type of roof, (2) the structure of indoor walls, (3) the number of dogs sharing sleeping areas of people (room-mate dogs), and (4) the number of people plus room-mate dogs, but not with just the number of people resident in the house. The interaction between insecticide use and a roof made of 'simbol', a locally available grass (Pennisetum sp.), also reflected a younger age structure of domestic bug populations. In infested houses, the density of bugs infected with Trypanosoma cruzi Chagas was significantly correlated with overall bug density. Our data suggest that the application of environmental management measures by the affected people, such as plastering of walls and modification of roofs, coupled with keeping dogs away from bedrooms and application of insecticides, should limit the domestic population density of T. infestans and thus reduce the transmission of T. cruzi to people.

  15. Evaporation from Pinus caribaea plantations on former grassland soils under maritime tropical conditions

    NASA Astrophysics Data System (ADS)

    Waterloo, M. J.; Bruijnzeel, L. A.; Vugts, H. F.; Rawaqa, T. T.

    1999-07-01

    Wet canopy and dry canopy evaporation from young and mature plantations of Pinus caribaea on former grassland soils under maritime tropical conditions in southwestern Viti Levu, Fiji, were determined using micrometeorological and hydrological techniques. Modeled annual evaporation totals (ET) of 1926 and 1717 mm were derived for the 6- and the 15-year-old stands, respectively. Transpiration made up 72% and 70% of annual ET, and modeled rainfall interception by the trees and litter layer was 20-22% and 8-9% in the young and the mature stands respectively. Monthly ET was related to forest leaf area index and was much higher than that for the kind of tall fire-climax Pennisetum polystachyon grassland replaced by the forests. Grassland reforestation resulted in a maximum decrease in annual water yield of 1180 mm on a plot basis, although it is argued that a reduction of (at least) 500-700 mm would be more realistic at the catchment scale. The impact of reforesting grassland on the water resources in southwest Viti Levu is enhanced by its location in a maritime, seasonal climate in the outer tropics, which favors a larger difference between annual forest and grassland evaporation totals than do equatorial regions.

  16. Allelopathic effects of litter Axonopus compressus against two weedy species and its persistence in soil.

    PubMed

    Samedani, B; Juraimi, A S; Rafii, M Y; Anuar, A R; Sheikh Awadz, S A; Anwar, M P

    2013-01-01

    This study investigated the allelopathic effect of Axonopus compressus litter on Asystasia gangetica and Pennisetum polystachion. In experiment 1 the bioassays with 0, 10, 30, and 50 g L⁻¹ of aqueous A. compressus litter leachate were conducted. Experiment 2 was carried out by incorporating 0, 10, 20, 30, 40, and 50 g L⁻¹ of A. compressus litter leachate into soil. In experiment 3, the fate of A. compressus litter leachate phenolics in the soil was investigated. A. compressus leachates did not affect the germination percentage of A. gangetica and P. polystachion, but delayed germination of A. gangetica seeds and decreased seed germination time of P. polystachion. A. compressus litter leachates affected weeds hypocotyl length. Hypocotyl length reductions of 18 and 31% were observed at the highest concentration (50 g L⁻¹) compared to the control in A. gangetica and P. polystachion, respectively. When concentration of A. compressus litter leachate-amended soil increased A. gangetica and P. polystachion seedling shoot length, root length, seedling weight and chlorophyll concentration were not affected. The 5-week decomposition study of A. compressus showed that the phenolic compounds in A. compressus litter abruptly decreased about 52% after two weeks and remained steady until the end of the incubation.

  17. Changes in nutritional and physico-chemical properties of pearl millet (Pennisetum glaucum) Ex-Borno variety flour as a result of malting.

    PubMed

    Obadina, Adewale O; Arogbokun, Christianah A; Soares, Antonio O; de Carvalho, Carlos Wanderlei Piler; Barboza, Henriqueta Talita; Adekoya, Ifeoluwa O

    2017-12-01

    The effect of malting periods on the nutritional composition and physico-chemical properties of flour from pearl millet (Ex-Borno) variety was evaluated. Grains were steeped at 25 °C for 24 h and germinated for different durations (12, 24, 36, 48, 60, 72, 84 and 96 h) before kilning at 55 °C for 18 h. The kilned seeds were devegetated, milled, sieved and analysed for their proximate composition, amino acid composition, total phenolic content, functional and pasting properties. The carbohydrate, fat and total phenolic contents of the pearl millet flour samples decreased while protein content increased with increased malting periods. Leucine was the dominant amino acid in the flour and 48 h-malted flour had the highest total amino acid (6.72). Peak viscosity significantly decreased as the malting period increased. Solubility index, pasting temperature and phenolic content of the flours ranged from 5.13 to 17.24%, 69.05 to 89.5 °C and 130.20 to 169.90 mg/100 g, respectively. Malting offers a means of improving the nutritional profile of Ex-Borno pearl millet flour with an increased protein and fibre and reduced fat content. Malting also enhanced the functional and pasting properties of the flour.

  18. Selenium volatilization in vegetated agricultural drainage sediment from the San Luis Drain, Central California.

    PubMed

    Bañuelos, G S; Lin, Z-Q; Arroyo, I; Terry, N

    2005-09-01

    The presence of large amounts of Se-laden agricultural drainage sediment in the San Luis Drain, Central California, poses a serious toxic threat to wildlife in the surrounding environment. Effective management of the drainage sediment becomes a practical challenge because the sediment is polluted with high levels of Se, B, and salts. This two-year field study was conducted to identify the best plant species that are salt and B tolerant and that have a superior ability of volatilizing Se from drainage sediment. The drainage sediment was mixed with clean soil, and vegetated with salado alfalfa (Medicago sativa 'salado'), salado grass (Sporobulus airoides 'salado'), saltgrass-turf (Distichlis spp. 'NYPA Turf'), saltgrass-forage (Distichlis spicata (L.) Greene), cordgrass (Spartina patens 'Flageo'), Leucaenia (Leucaena leucocephola), elephant grass (Pennistum purpureum), or wild type-Brassica (Brassica spp.). Results show that elephant grass produced the greatest amount of biomass and accumulated highest concentrations of B. Highest concentrations of Se, S, and Cl were observed in wild-type Brassica. Biogenic volatilization of Se by plants and soil microbes was greater in summer. Among the treatments, the mean daily rates of Se volatilization (microg Se m(-2)d(-1)) were wild-type Brassica (39) > saltgrass-turf (31) > cordgrass (27) > saltgrass forage (24) > elephant grass (22) > salado grass (21) > leucaenia (19) > salado alfalfa (14) > irrigated bare soil (11) > non-irrigated bare soil (6). Overall, rates of Se volatilization in drainage sediment were relatively low due to high levels of sulfate. To manage Se in drainage sediment by phytoremediation, the biological volatilization process needs to be enhanced substantially under field conditions.

  19. Ecophysiological responses of native and invasive grasses to simulated warming and drought

    NASA Astrophysics Data System (ADS)

    Ravi, S.; Law, D. J.; Wiede, A.; Barron-Gafford, G. A.; Breshears, D. D.; Dontsova, K.; Huxman, T. E.

    2011-12-01

    Climate models predict that many arid regions around the world - including the North American deserts - may become affected more frequently by recurrent droughts. At the same time, these regions are experiencing rapid vegetation transformations such as invasion by exotic grasses. Thus, understanding the ecophysiological processes accompanying exotic grass invasion in the context of rising temperatures and recurrent droughts is fundamental to global change research. Under ambient and warmer (+ 4° C) conditions inside the Biosphere 2 facility, we compared the ecophysiological responses (e.g. photosynthesis, stomatal conductance, pre-dawn leaf water potential, light & CO2 response functions, biomass) of a native grass - Heteropogan contortus (Tangle head) and an invasive grass - Pennisetum ciliare (Buffel grass) growing in single and mixed communities. Further, we monitored the physiological responses and mortality of these plant communities under moisture stress conditions, simulating a global change-type-drought. The results indicate that the predicted warming scenarios may enhance the invasibility of desert landscapes by exotic grasses. In this study, buffel grass assimilated more CO2 per unit leaf area and out-competed native grasses more efficiently in a warmer environment. However, scenarios involving a combination of drought and warming proved disastrous to both the native and invasive grasses, with drought-induced grass mortality occurring at much shorter time scales under warmer conditions.

  20. Synthesis of the low molecular weight heat shock proteins in plants

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mansfield, M.A.; Key, J.L.

    1987-08-01

    Heat shock of living tissue induces the synthesis of a unique group of proteins, the heat shock proteins. In plants, the major group of heat shock proteins has a molecular mass of 15 to 25 kilodaltons. Accumulation to these proteins to stainable levels has been reported in only a few species. To examine accumulation of the low molecular weight heat shock proteins in a broader range of species, two-dimensional electrophoresis was used to resolve total protein from the following species: soybean (Glycine max L. Merr., var Wayne), pea (Pisum sativum L., var Early Alaska), sunflower (Helianthus annuus L.), wheat (Triticummore » asetivum L.), rice (Oryza sativa L., cv IR-36), maize (Zea mays L.), pearl millet (Pennisetum americanum L. Leeke, line 23DB), and Panicum miliaceum L. When identified by both silver staining and incorporation of radiolabel, a diverse array of low molecular weight heat shock proteins was synthesized in each of these species. These proteins accumulated to significant levels after three hours of heat shock but exhibited considerable heterogeneity in isoelectric point, molecular weight, stainability, and radiolabel incorporation. Although most appeared to be synthesized only during heat shock, some were detectable at low levels in control tissue. Compared to the monocots, a higher proportion of low molecular weight heat shock proteins was detectable in control tissues from dicots.« less

  1. Microalgae biofilm in soil: Greenhouse gas emissions, ammonia volatilization and plant growth.

    PubMed

    Castro, Jackeline de Siqueira; Calijuri, Maria Lúcia; Assemany, Paula Peixoto; Cecon, Paulo Roberto; de Assis, Igor Rodrigues; Ribeiro, Vinícius José

    2017-01-01

    Microalgal biofilm in soils represents an alternative fertilization method for agricultural sustainability. In the present study, greenhouse gas emission, soil ammonia volatilization, and the growth of Pennisetum glaucum were evaluated under the effect of a microalgal biofilm, commercial urea, and a control (without application of a nitrogen source). CH 4 emissions were equal for the three treatments (p>0.05). CO 2 emissions significantly increased in microalgal biofilm treatment (p<0.01), which was also responsible for the highest N 2 O emissions (p<0.01). The ammonia (NNH 3 ) volatilization losses were 4.63%, 18.98%, and 0.82% for the microalgal biofilm, urea, and control treatments, respectively. The main differences in soil characteristics were an increase in nitrogen and an increase in cation exchange capacity (p<0.01) caused by the algal biomass application to the soil. The soil organic matter content significantly differed (p<0.05) among the three treatments, with the microalgal biofilm treatment having the greatest increase in soil organic matter. Significant differences were observed for shoot dry matter mass and nitrogen content in the plants from both treatments where nitrogen sources were applied. All treatments differed from each other in leaf dry matter mass, with the urea treatment increasing the most. Chlorella vulgaris was the dominant microalgal specie in the soil. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Population dynamics of caterpillars on three cover crops before sowing cotton in Mato Grosso (Brazil).

    PubMed

    Silvie, P J; Menzel, C A; Mello, A; Coelho, A G

    2010-01-01

    Direct seeding mulch-based cropping systems under a preliminary cover crop such as millet are common in some areas of Brazil. Lepidopteran pests that damage cotton, soybean and maize crops can proliferate on cover crops, so preventive chemical treatments are necessary. Very little data is available on these pests on cover crops. This paper presents the dynamics of Spodoptera frugiperda, S. eridania, Mocis latipes and Diatraea saccharalis caterpillars monitored at Primavera do Leste, Mato Grosso state (Brazil) during the of 2005/2006 and 2006/2007 cropping seasons on four cover crops, i.e. finger millet (Eleusine coracana), pearl millet (Pennisetum glaucum), sorghum (Sorghum bicolor) and ruzigrass (Brachiaria ruziziensis). The pests were visually counted on plants within a 1 m2 transect (wooden frame). Caterpillars were reared to facilitate identification of collected species and parasitoids. Many S. frugiperda caterpillars were observed on millet in 2005, with a maximum of 37 caterpillars/m2. On sorghum, we found 30 caterpillars/m2, or 0.83 caterpillars/plant. The Diatraea borer attacked sorghum later than the other pests. M. latipes was also observed on millet. The millet cover crop had to be dried for at least 1 month before direct drilling the main cotton crop in order to impede S. frugiperda infestations on cotton plantlets, thus avoiding the need for substantial resowing. The comparative methodological aspects are discussed.

  3. Perennial Grass and Native Wildflowers: A Synergistic Approach to Habitat Management

    PubMed Central

    Xavier, Shereen S.; Olson, Dawn M.; Coffin, Alisa W.; Strickland, Timothy C.; Schmidt, Jason M.

    2017-01-01

    Marginal agricultural land provides opportunities to diversify landscapes by producing biomass for biofuel, and through floral provisioning that enhances arthropod-mediated ecosystem service delivery. We examined the effects of local spatial context (adjacent to woodland or agriculture) and irrigation (irrigation or no irrigation) on wildflower bloom and visitation by arthropods in a biofeedstocks-wildflower habitat buffer design. Twenty habitat buffer plots were established containing a subplot of Napier grass (Pennisetum perpureum Schumach) for biofeedstock, three commercial wildflower mix subplots, and a control subplot containing spontaneous weeds. Arthropods and flowers were visually observed in quadrats throughout the season. At the end of the season we measured soil nutrients and harvested Napier biomass. We found irrespective of buffer location or irrigation, pollinators were observed more frequently early in the season and on experimental plots with wildflowers than on weeds in the control plots. Natural enemies showed a tendency for being more common on plots adjacent to a wooded border, and were also more commonly observed early in the season. Herbivore visits were infrequent and not significantly influenced by experimental treatments. Napier grass yields were high and typical of first-year yields reported regionally, and were not affected by location context or irrigation. Our results suggest habitat management designs integrating bioenergy crop and floral resources provide marketable biomass and habitat for beneficial arthropods. PMID:28937651

  4. Perennial Grass and Native Wildflowers: A Synergistic Approach to Habitat Management.

    PubMed

    Xavier, Shereen S; Olson, Dawn M; Coffin, Alisa W; Strickland, Timothy C; Schmidt, Jason M

    2017-09-22

    Marginal agricultural land provides opportunities to diversify landscapes by producing biomass for biofuel, and through floral provisioning that enhances arthropod-mediated ecosystem service delivery. We examined the effects of local spatial context (adjacent to woodland or agriculture) and irrigation (irrigation or no irrigation) on wildflower bloom and visitation by arthropods in a biofeedstocks-wildflower habitat buffer design. Twenty habitat buffer plots were established containing a subplot of Napier grass ( Pennisetum perpureum Schumach) for biofeedstock, three commercial wildflower mix subplots, and a control subplot containing spontaneous weeds. Arthropods and flowers were visually observed in quadrats throughout the season. At the end of the season we measured soil nutrients and harvested Napier biomass. We found irrespective of buffer location or irrigation, pollinators were observed more frequently early in the season and on experimental plots with wildflowers than on weeds in the control plots. Natural enemies showed a tendency for being more common on plots adjacent to a wooded border, and were also more commonly observed early in the season. Herbivore visits were infrequent and not significantly influenced by experimental treatments. Napier grass yields were high and typical of first-year yields reported regionally, and were not affected by location context or irrigation. Our results suggest habitat management designs integrating bioenergy crop and floral resources provide marketable biomass and habitat for beneficial arthropods.

  5. Fabrication Of Biogenic Silver Nanoparticles Using Agricultural Crop Plant Leaf Extracts

    NASA Astrophysics Data System (ADS)

    Rajani, P.; SriSindhura, K.; Prasad, T. N. V. K. V.; Hussain, O. M.; Sudhakar, P.; Latha, P.; Balakrishna, M.; Kambala, V.; Reddy, K. Raja

    2010-10-01

    Nanoparticles are being viewed as fundamental building blocks of nanotechnology. Biosynthesis of nanoparticles by plant extracts is currently under exploitation. Use of agricultural crop plant extracts for synthesis of metal nanoparticles would add a new dimension to the agricultural sector in the utilization of crop waste. Silver has long been recognized as having an inhibitory effect towards many bacterial strains and microorganisms commonly present in medical and industrial processes. Four pulse crop plants and three cereal crop plants (Vigna radiata, Arachis hypogaea, Cyamopsis tetragonolobus, Zea mays, Pennisetum glaucum, Sorghum vulgare) were used and compared for their extra cellular synthesis of metallic silver nanoparticles. Stable silver nanoparticles were formed by treating aqueous solution of AgNO3 with the plant leaf extracts as reducing agent at temperatures 50 °C-95 °C. UV-Visible spectroscopy was utilized to monitor the formation of silver nanoparticles. XRD analysis of formed silver nanoparticles revealed face centered cubic structure with (111), (200), (220) and (311) planes. SEM and EDAX analysis confirm the size of the formed silver nanoparticles to be in the range of 50-200 nm. Our proposed work offers a enviro-friendly method for biogenic silver nanoparticles production. This could provide a faster synthesis rate comparable to those of chemical methods and potentially be used in areas such as cosmetics, food and medical applications.

  6. Terminal drought-tolerant pearl millet [Pennisetum glaucum (L.) R. Br.] have high leaf ABA and limit transpiration at high vapour pressure deficit

    PubMed Central

    Kholová, Jana; Hash, C. T.; Kumar, P. Lava; Yadav, Rattan S.; Kočová, Marie; Vadez, Vincent

    2010-01-01

    It was previously shown that pearl millet genotypes carrying a terminal drought tolerance quantitative trait locus (QTL) had a lower transpiration rate (Tr; g cm−2 d−1) under well-watered conditions than sensitive lines. Here experiments were carried out to test whether this relates to leaf abscisic acid (ABA) and Tr concentration at high vapour pressure deficit (VPD), and whether that leads to transpiration efficiency (TE) differences. These traits were measured in tolerant/sensitive pearl millet genotypes, including near-isogenic lines introgressed with a terminal drought tolerance QTL (NIL-QTLs). Most genotypic differences were found under well-watered conditions. ABA levels under well-watered conditions were higher in tolerant genotypes, including NIL-QTLs, than in sensitive genotypes, and ABA did not increase under water stress. Well-watered Tr was lower in tolerant than in sensitive genotypes at all VPD levels. Except for one line, Tr slowed down in tolerant lines above a breakpoint at 1.40–1.90 kPa, with the slope decreasing >50%, whereas sensitive lines showed no change in that Tr response across the whole VPD range. It is concluded that two water-saving (avoidance) mechanisms may operate under well-watered conditions in tolerant pearl millet: (i) a low Tr even at low VPD conditions, which may relate to leaf ABA; and (ii) a sensitivity to higher VPD that further restricts Tr, which suggests the involvement of hydraulic signals. Both traits, which did not lead to TE differences, could contribute to absolute water saving seen in part due to dry weight increase differences. This water saved would become critical for grain filling and deserves consideration in the breeding of terminal drought-tolerant lines. PMID:20142425

  7. Terminal drought-tolerant pearl millet [Pennisetum glaucum (L.) R. Br.] have high leaf ABA and limit transpiration at high vapour pressure deficit.

    PubMed

    Kholová, Jana; Hash, C T; Kumar, P Lava; Yadav, Rattan S; Kocová, Marie; Vadez, Vincent

    2010-03-01

    It was previously shown that pearl millet genotypes carrying a terminal drought tolerance quantitative trait locus (QTL) had a lower transpiration rate (Tr; g cm(-2) d(-1)) under well-watered conditions than sensitive lines. Here experiments were carried out to test whether this relates to leaf abscisic acid (ABA) and Tr concentration at high vapour pressure deficit (VPD), and whether that leads to transpiration efficiency (TE) differences. These traits were measured in tolerant/sensitive pearl millet genotypes, including near-isogenic lines introgressed with a terminal drought tolerance QTL (NIL-QTLs). Most genotypic differences were found under well-watered conditions. ABA levels under well-watered conditions were higher in tolerant genotypes, including NIL-QTLs, than in sensitive genotypes, and ABA did not increase under water stress. Well-watered Tr was lower in tolerant than in sensitive genotypes at all VPD levels. Except for one line, Tr slowed down in tolerant lines above a breakpoint at 1.40-1.90 kPa, with the slope decreasing >50%, whereas sensitive lines showed no change in that Tr response across the whole VPD range. It is concluded that two water-saving (avoidance) mechanisms may operate under well-watered conditions in tolerant pearl millet: (i) a low Tr even at low VPD conditions, which may relate to leaf ABA; and (ii) a sensitivity to higher VPD that further restricts Tr, which suggests the involvement of hydraulic signals. Both traits, which did not lead to TE differences, could contribute to absolute water saving seen in part due to dry weight increase differences. This water saved would become critical for grain filling and deserves consideration in the breeding of terminal drought-tolerant lines.

  8. Antibacterial, antioxidant and anti-proliferative properties and zinc content of five south Portugal herbs.

    PubMed

    Nunes, Ricardo; Pasko, Pawel; Tyszka-Czochara, Malgorzata; Szewczyk, Agnieszka; Szlosarczyk, Marek; Carvalho, Isabel S

    2017-12-01

    Crataegus monogyna L. (Rosaceae) (CM), Equisetum telmateia L. (Equisataceae) (ET), Geranium purpureum Vil. (Geraniaceae) (GP), Mentha suaveolens Ehrh. (Lamiaceae) (MS), and Lavandula stoechas L. spp. luisieri (Lamiaceae) (LS) are all medicinal. To evaluate the antioxidant, antiproliferative and antimicrobial activities of plant extracts and quantify individual phenolics and zinc. Aerial part extracts were prepared with water (W), ethanol (E) and an 80% mixture (80EW). Antioxidant activity was measured with TAA, FRAP and RP methods. Phenolics were quantified with a HPLC. Zinc was quantified using voltammetry. Antibacterial activity (after 48 h) was tested using Enterococcus faecalis, Bacillus cereus, Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and Listeria monocytogenes. Antiproliferative activity (after 24 h) was tested using HEP G2 cells and fibroblasts. Solvents influenced results; the best were E and 80EW. GP had the highest antioxidant activity (TAA and FRAP of 536.90 mg AAE/g dw and 783.48 mg TE/g dw, respectively). CM had the highest zinc concentration (37.21 mg/kg) and phenolic variety, with neochlorogenic acid as the most abundant (92.91 mg/100 g dw). LS was rich in rosmarinic acid (301.71 mg/100 g dw). GP and LS inhibited the most microorganisms: B. cereus, E. coli and S. aureus. GP also inhibited E. faecalis. CM had the lowest MIC: 5830 μg/mL. The antibacterial activity is explained by the phenolics present. LS and CM showed the most significant anti-proliferative activity, which is explained by their zinc content. The most promising plants for further studies are CM, LS and GP.

  9. NUTRITION OF CELLULAR SLIME MOLDS I.

    PubMed Central

    Hohl, Hans-Rudolf; Raper, Kenneth B.

    1963-01-01

    Hohl, Hans-Rudolf (University of Wisconsin, Madison) and Kenneth B. Raper. Nutrition of cullular slime molds. I. Growth on living and dead bacteria. J. Bacteriol. 85:191–198. 1963.—Methods for growing selected species of cellular slime molds in liquid culture on living and dead bacteria are described. Species investigated included Polysphondylium pallidum, P. violaceum, Dictyostelium discoideum, and D. purpureum. Maximal growth of myxamoebae occurred in suspensions of 1010 living bacteria (Escherichia coli B/r)/ml in Sörensen's phosphate buffer (pH 6.0), reaching a density of 107 to 2 × 107 cells/ml in 48 hr. The generation time for the different slime molds ranged from 2.4 hr for P. violaceum to 2.9 hr for D. discoideum (strain V-12). Good growth of P. pallidum occurred between pH 3.6 and 7.8. The slime molds grew less well on dead (autoclaved) than on living bacteria and, except for P. pallidum, the amount and rate of growth decreased markedly as the time of autoclaving was increased from 2.5 to 80 min. Bacteria killed with propylene oxide supported growth equal to those autoclaved for a few minutes. The myxamoebae were very sensitive to the osmotic pressure of the culture medium, especially in the presence of living bacteria, and addition of as little as 0.01 m NaCl caused a measurable decrease in slime mold growth. The culture techniques employed afford useful methods for investigating the nutritional requirements of the cellular slime molds, and the experiments described provide the bases for subsequent studies relating to the axenic cultivation of these singular microorganisms. Images PMID:13961228

  10. Traditional production, consumption and storage of Kunu--a non alcoholic cereal beverage.

    PubMed

    Gaffa, T; Jideani, I A; Nkama, I

    2002-01-01

    A survey of the production, consumption and storage of Kunu was carried out. Some of the information included consumption rate, processing techniques and equipment, producer's status and grains used. About 73% consume Kunu daily, 26% occasionally; 1% know it is produced but may or may not be consuming it. Millet (Pennisetum typhoideum), sorghum (Sorghum vulgare), maize (Zea mays), rice (Oryza sativa) and acha (Digitalis exilis) were used in its production in decreasing order of preference. The grains were used singly or combined; sorghum/millet was the most common combination in a ratio of 1:2 (w/w). Steeping was done in ordinary water for 12-72 h, depending on the grain type, in local clay pots, plastic buckets, calabashes or basins or 5-7 h in warm water (60-70 degrees C). The grains were dry or wet milled with or without spices such as ginger, red pepper, black pepper, clove and garlic. Other ingredients introduced included: sweet potatoes, malted rice, malted sorghum and Cadaba farinosa crude extract. Both dry and wet milling was done with grinding mills, mill stones or mortar and pestle, depending on locality. The product was then cooked into a thin free flowing gruel. The various types of kunu were: Kunun zaki, Kunun gyada, Kunun akamu, Kunun tsamiya, Kunun baule, Kunun jiko, Amshau and Kunun gayamba. Kunun zaki was the most commonly consumed. Production and consumption cut across all social classes of the society.

  11. Chloromonilinic Acids C and D, Phytotoxic Tetrasubstituted 3-Chromanonacrylic Acids Isolated from Cochliobolus australiensis with Potential Herbicidal Activity against Buffelgrass (Cenchrus ciliaris).

    PubMed

    Masi, Marco; Meyer, Susan; Clement, Suzette; Pescitelli, Gennaro; Cimmino, Alessio; Cristofaro, Massimo; Evidente, Antonio

    2017-10-27

    The fungal pathogen Cochliobolus australiensis isolated from infected leaves of the invasive weed buffelgrass (Pennisetum ciliare) was grown in vitro to evaluate its ability to produce phytotoxic metabolites that could potentially be used as natural herbicides against this weed. Two new tetrasubstituted 3-chromanonacrylic acids, named chloromonilinic acids C (1) and D (2), were isolated from the liquid cultures of C. australiensis, together with the known chloromonilinic acid B. Chloromonilinic acids C and D were characterized by spectroscopic and chemical methods as (E)-3-chloro-3-[(5-hydroxy-3-(1-hydroxy-2-methoxy-2-oxoethyl)-7-methyl-4-oxo-4H-chromen-2-yl)]acrylic acid and (Z)-3-chloro-3-[(5-hydroxy-3-(2-methoxy-2-oxoethyl)-7-methyl-4-oxo-4H-chromen-2-yl)]acrylic acid, respectively. The stereochemistry of chloromonilinic acids C and D was determined using a combination of spectroscopic and computational methods, including electronic circular dichroism. The fungus produced these compounds in two different liquid media together with cochliotoxin, radicinin, radicinol, and their 3-epimers. The radicinin-related compounds were also produced when the fungus was grown in wheat seed solid culture, but chloromonilinic acids were not found in the solid culture organic extract. All three chloromonilinic acids were toxic to buffelgrass in a seedling elongation bioassay, with significantly delayed germination and dramatically reduced radicle growth, especially at a concentration of 5 × 10 -3 M.

  12. Ecophysiological Responses of Invasive and Native Grass Communities with Simulated Warming

    NASA Astrophysics Data System (ADS)

    Quade, B.; Ravi, S.; Huxman, T. E.

    2010-12-01

    William Quade1, Sujith Ravi2, Ashley Weide2, Greg Barron-Gafford2, Katerina Dontsova2 and Travis E Huxman2 1Carthage College, WI 2 B2 Earthscience & UA Biosphere 2, University of Arizona, Tucson. Abstract Climate change, anthropogenic disturbances and lack of proper management practices have rendered many arid regions susceptible to invasions by exotic grasses with consequent ecohydrological, biogeochemical and socio economic implications. Thus, understanding the ecophysiological processes driving these large-scale vegetation shifts in drylands, in the context of rising temperatures and recurrent droughts is fundamental to global change research. Using the Biosphere 2 facility to maintain distinct temperature treatments of ambient and predicted warmer conditions (+ 4o C) inside, we compared the physiological (e.g. photosynthesis, stomatal conductance, biomass) responses of a native grass - Heteropogan contortus (Tanglehead) and an invasive grass - Pennisetum ciliare (Buffelgrass) growing in single and mixed communities. The results indicate that Buffelgrass can assimilate more CO2 per unit leaf area under current conditions, though warming seems to inhibit the performance when looking at biomass, photosynthesis and stomatal conductance. Under similar moisture regimes Buffelgrass performed better than Tangle head in mixed communities regardless of the temperature. Both grasses had decrease in stomatal conductance with warmer conditions, however the Buffel grass did not have the same decrease of conductance when planted in a mixed communities. Key words: Buffelgrass, Tanglehead, Biosphere 2, stomatal conductance, climate change

  13. Recombination within the apospory specific genomic region leads to the uncoupling of apomixis components in Cenchrus ciliaris.

    PubMed

    Conner, Joann A; Gunawan, Gunawati; Ozias-Akins, Peggy

    2013-07-01

    Apomixis enables the clonal propagation of maternal genotypes through seed. If apomixis could be harnessed via genetic engineering or introgression, it would have a major economic impact for agricultural crops. In the grass species Pennisetum squamulatum and Cenchrus ciliaris (syn. P. ciliare), apomixis is controlled by a single dominant "locus", the apospory-specific genomic region (ASGR). For P. squamulatum, 18 published sequenced characterized amplified region (SCAR) markers have been identified which always co-segregate with apospory. Six of these markers are conserved SCARs in the closely related species, C. ciliaris and co-segregate with the trait. A screen of progeny from a cross of sexual × apomictic C. ciliaris genotypes identified a plant, A8, retaining two of the six ASGR-linked SCAR markers. Additional and newly identified ASGR-linked markers were generated to help identify the extent of recombination within the ASGR. Based on analysis of missing markers, the A8 recombinant plant has lost a significant portion of the ASGR but continues to form aposporous embryo sacs. Seedlings produced from aposporous embryo sacs are 6× in ploidy level and hence the A8 recombinant does not express parthenogenesis. The recombinant A8 plant represents a step forward in reducing the complexity of the ASGR locus to determine the factor(s) required for aposporous embryo sac formation and documents the separation of expression of the two components of apomixis in C. ciliaris.

  14. Effects of Alien Plants on Ecosystem Structure and Functioning and Implications for Restoration: Insights from Three Degraded Sites in South African Fynbos

    NASA Astrophysics Data System (ADS)

    Gaertner, Mirijam; Richardson, David M.; Privett, Sean D. J.

    2011-07-01

    We investigated the type and extent of degradation at three sites on the Agulhas Plain, South Africa: an old field dominated by the alien grass Pennisetum clandestinum Pers . (kikuyu), an abandoned Eucalyptus plantation, and a natural fynbos community invaded by nitrogen fixing—Australian Acacia species. These forms of degradation are representative of many areas in the region. By identifying the nature and degree of ecosystem degradation we aimed to determine appropriate strategies for restoration in this biodiversity hotspot. Vegetation surveys were conducted at degraded sites and carefully selected reference sites. Soil-stored propagule seed banks and macro- and micro-soil nutrients were determined. Species richness, diversity and native cover under Eucalyptus were extremely low compared to the reference site and alterations of the soil nutrients were the most severe. The cover of indigenous species under Acacia did not differ significantly from that in reference sites, but species richness was lower under Acacia and soils were considerably enriched. Native species richness was much lower in the kikuyu site, but soil nutrient status was similar to the reference site. Removal of the alien species alone may be sufficient to re-initiate ecosystem recovery at the kikuyu site, whereas active restoration is required to restore functioning ecosystems dominated by native species in the Acacia thicket and the Eucalyptus plantation. To restore native plant communities we suggest burning, mulching with sawdust and sowing of native species.

  15. Effect of high moisture storage of pearl millet (Pennisetum typhoides) with or without feed enzymes on growth and nutrient utilization in broiler chickens.

    PubMed

    Manwar, Satish Jagannath; Mandal, Asit Baran

    2009-08-01

    Effect of reconstitution of pearl millet with or without enzymes on its utilization in broiler chickens was studied. The pearl millet grains were reconstituted by adding water to raise the moisture level to 30%, followed by storage in sealed plastic buckets with or without feed enzymes (0.5 g/kg) for 21 days at room temperature (25 degrees C). Subsequently, the grains were sun-dried to reduce the moisture content up to 10% to avoid mould growth. Nine dietary treatments were formulated incorporating pearl millet either raw with or without enzymes or reconstituted with or without enzymes in maize-soya based control diet replacing maize at 50 and 75% levels. The birds fed on diets containing enzyme reconstituted pearl millet accrued higher body weight than maize based control diet. Addition of enzymes to raw pearl-millet based diet improved the body weight gain significantly. The reconstitution of pearl millet with or without enzymes increased (P < 0.01) the dietary nitrogen corrected apparent metabolizable energy (AMEn) values and the highest improvement (6.11%) was recorded in diets containing pearl millet reconstituted with enzymes at 75% level of maize replacement. The percent nitrogen retention in pearl millet based diets was comparable to maize based control diet. It may be concluded that the supplementation of the feed enzymes or reconstitution of pearl millet may improve the utilization of pearl millet in broiler chickens.

  16. Risk element sorption/desorption characteristics of dry olive residue: a technique for the potential immobilization of risk elements in contaminated soils.

    PubMed

    Hovorka, Miloš; Száková, Jiřina; García-Sánchez, Mercedes; Acebal, Mercedes Blanc; García-Romera, Inmaculada; Tlustoš, Pavel

    2016-11-01

    Olive oil production is one of the most relevant agroindustrial activities in the Mediterranean region and generates a huge amount of both solid and semi-solid wastes, the uncontrolled disposal of which might lead to serious environmental problems. Due to its organic matter and mineral nutrient content, the waste material can be applied to agricultural soil as a fertilizer. However, due to its high organic matter content, dry olive residue (DOR), commonly called "alperujo," has the potential to immobilize risk elements in contaminated soils. The main objective of this study was to assess the possible effect of DOR on sorption of risk elements such as cadmium (Cd), lead (Pb), and zinc (Zn) in the soil. A set of batch sorption experiments were carried out to assess the ability of DOR to adsorb Cd, Pb, and Zn where the effect of the preceding biotransformation of DOR by four species of fungi: Penicillium chrysogenum, Coriolopsis floccosa, Bjerkhandera adusta, and Chondrostereum purpureum was compared. The Freundlich and Langmuir sorption isotherms were calculated to assess the sorption characteristics of both transformed and non-transformed DOR. The results showed good potential sorption capacity of DOR, especially for Pb and to a lesser extent for Cd and Zn. Better sorption characteristics were reported for the biotransformed DOR samples, which are expected to show higher humification of the organic matter. However, the desorption experiments showed weakness and instability of the DOR-bound elements, especially in the case of Zn. Thus, future research should aim to verify the DOR sorption pattern in contaminated soil as well as the potential stabilization of the DOR element bounds where the increase of the pH levels of the DOR samples needs to be taken into account.

  17. Risk element immobilization/stabilization potential of fungal-transformed dry olive residue and arbuscular mycorrhizal fungi application in contaminated soils.

    PubMed

    García-Sánchez, Mercedes; Stejskalová, Tereza; García-Romera, Inmaculada; Száková, Jiřina; Tlustoš, Pavel

    2017-10-01

    The use of biotransformed dry olive residue (DOR) as organic soil amendment has recently been proposed due to its high contents of stabilized organic matter and nutrients. The potential of biotransformed DOR to immobilize risk elements in contaminated soils might qualify DOR as a potential risk element stabilization agent for in situ soil reclamation practices. In this experiment, the mobility of risk elements in response to Penicillium chrysogenum-10-transformed DOR, Funalia floccosa-transformed DOR, Bjerkandera adusta-transformed DOR, and Chondrostereum purpureum-transformed DOR as well as arbuscular mycorrhizal fungi (AMF), Funneliformis mosseae, inoculation was investigated. We evaluated the effect of these treatments on risk element uptake by wheat (Triticum aestivum L.) plants in a pot experiment with Cd, Pb, and Zn contaminated soil. The results showed a significant impact of the combined treatment (biotransformed DOR and AMF inoculation) on wheat plant growth and element mobility. The mobile proportions of elements in the treated soils were related to soil pH; with increasing pH levels, Cd, Cu, Fe, Mn, P, Pb, and Zn mobility decreased significantly (r values between -0.36 and -0.46), while Ca and Mg mobility increased (r = 0.63, and r = 0.51, respectively). The application of biotransformed DOR decreased risk element levels (Cd, Zn), and nutrient concentrations (Ca, Cu, Fe, Mg, Mn) in the aboveground biomass, where the elements were retained in the roots. Thus, biotransformed DOR in combination with AMF resulted in a higher capacity of wheat plants to grow under detrimental conditions, being able to accumulate high amounts of risk elements in the roots. However, risk element reduction was insufficient for safe crop production in the extremely contaminated soil. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Discriminating crop, weeds and soil surface with a terrestrial LIDAR sensor.

    PubMed

    Andújar, Dionisio; Rueda-Ayala, Victor; Moreno, Hugo; Rosell-Polo, Joan Ramón; Escolá, Alexandre; Valero, Constantino; Gerhards, Roland; Fernández-Quintanilla, César; Dorado, José; Griepentrog, Hans-Werner

    2013-10-29

    In this study, the evaluation of the accuracy and performance of a light detection and ranging (LIDAR) sensor for vegetation using distance and reflection measurements aiming to detect and discriminate maize plants and weeds from soil surface was done. The study continues a previous work carried out in a maize field in Spain with a LIDAR sensor using exclusively one index, the height profile. The current system uses a combination of the two mentioned indexes. The experiment was carried out in a maize field at growth stage 12-14, at 16 different locations selected to represent the widest possible density of three weeds: Echinochloa crus-galli (L.) P.Beauv., Lamium purpureum L., Galium aparine L.and Veronica persica Poir.. A terrestrial LIDAR sensor was mounted on a tripod pointing to the inter-row area, with its horizontal axis and the field of view pointing vertically downwards to the ground, scanning a vertical plane with the potential presence of vegetation. Immediately after the LIDAR data acquisition (distances and reflection measurements), actual heights of plants were estimated using an appropriate methodology. For that purpose, digital images were taken of each sampled area. Data showed a high correlation between LIDAR measured height and actual plant heights (R2 = 0.75). Binary logistic regression between weed presence/absence and the sensor readings (LIDAR height and reflection values) was used to validate the accuracy of the sensor. This permitted the discrimination of vegetation from the ground with an accuracy of up to 95%. In addition, a Canonical Discrimination Analysis (CDA) was able to discriminate mostly between soil and vegetation and, to a far lesser extent, between crop and weeds. The studied methodology arises as a good system for weed detection, which in combination with other principles, such as vision-based technologies, could improve the efficiency and accuracy of herbicide spraying.

  19. Discriminating Crop, Weeds and Soil Surface with a Terrestrial LIDAR Sensor

    PubMed Central

    Andújar, Dionisio; Rueda-Ayala, Victor; Moreno, Hugo; Rosell-Polo, Joan Ramón; Escolà, Alexandre; Valero, Constantino; Gerhards, Roland; Fernández-Quintanilla, César; Dorado, José; Griepentrog, Hans-Werner

    2013-01-01

    In this study, the evaluation of the accuracy and performance of a light detection and ranging (LIDAR) sensor for vegetation using distance and reflection measurements aiming to detect and discriminate maize plants and weeds from soil surface was done. The study continues a previous work carried out in a maize field in Spain with a LIDAR sensor using exclusively one index, the height profile. The current system uses a combination of the two mentioned indexes. The experiment was carried out in a maize field at growth stage 12–14, at 16 different locations selected to represent the widest possible density of three weeds: Echinochloa crus-galli (L.) P.Beauv., Lamium purpureum L., Galium aparine L.and Veronica persica Poir.. A terrestrial LIDAR sensor was mounted on a tripod pointing to the inter-row area, with its horizontal axis and the field of view pointing vertically downwards to the ground, scanning a vertical plane with the potential presence of vegetation. Immediately after the LIDAR data acquisition (distances and reflection measurements), actual heights of plants were estimated using an appropriate methodology. For that purpose, digital images were taken of each sampled area. Data showed a high correlation between LIDAR measured height and actual plant heights (R2 = 0.75). Binary logistic regression between weed presence/absence and the sensor readings (LIDAR height and reflection values) was used to validate the accuracy of the sensor. This permitted the discrimination of vegetation from the ground with an accuracy of up to 95%. In addition, a Canonical Discrimination Analysis (CDA) was able to discriminate mostly between soil and vegetation and, to a far lesser extent, between crop and weeds. The studied methodology arises as a good system for weed detection, which in combination with other principles, such as vision-based technologies, could improve the efficiency and accuracy of herbicide spraying. PMID:24172283

  20. Relative contribution of phytates, fibers, and tannins to low iron and zinc in vitro solubility in pearl millet (Pennisetum glaucum) flour and grain fractions.

    PubMed

    Lestienne, Isabelle; Caporiccio, Bertrand; Besançon, Pierre; Rochette, Isabelle; Trèche, Serge

    2005-10-19

    In vitro digestions were performed on pearl millet flours with decreased phytate contents and on two dephytinized or nondephytinized pearl millet grain fractions, a decorticated fraction, and a bran fraction with low and high fiber and tannin contents, respectively. Insoluble residues of these digestions were then incubated with buffer or enzymatic solutions (xylanases and/or phytases), and the quantities of indigestible iron and zinc released by these different treatments were determined. In decorticated pearl millet grain, iron was chelated by phytates and by insoluble fibers, whereas zinc was almost exclusively chelated by phytates. In the bran of pearl millet grain, a high proportion of iron was chelated by iron-binding phenolic compounds, while the rest of iron as well as the majority of zinc were chelated in complexes between phytates and fibers. The low effect of phytase action on iron and zinc solubility of bran of pearl millet grain shows that, in the case of high fiber and tannin contents, the chelating effect of these compounds was higher than that of phytates.

  1. Mapping Quantitative Trait Loci Controlling High Iron and Zinc Content in Self and Open Pollinated Grains of Pearl Millet [Pennisetum glaucum (L.) R. Br.

    PubMed Central

    Kumar, Sushil; Hash, Charles T.; Thirunavukkarasu, Nepolean; Singh, Govind; Rajaram, Vengaldas; Rathore, Abhishek; Senapathy, Senthilvel; Mahendrakar, Mahesh D.; Yadav, Rattan S.; Srivastava, Rakesh K.

    2016-01-01

    Pearl millet is a multipurpose grain/fodder crop of the semi-arid tropics, feeding many of the world’s poorest and most undernourished people. Genetic variation among adapted pearl millet inbreds and hybrids suggests it will be possible to improve grain micronutrient concentrations by selective breeding. Using 305 loci, a linkage map was constructed to map QTLs for grain iron [Fe] and zinc [Zn] using replicated samples of 106 pearl millet RILs (F6) derived from ICMB 841-P3 × 863B-P2. The grains of the RIL population were evaluated for Fe and Zn content using atomic absorption spectrophotometer. Grain mineral concentrations ranged from 28.4 to 124.0 ppm for Fe and 28.7 to 119.8 ppm for Zn. Similarly, grain Fe and Zn in open pollinated seeds ranged between 22.4–77.4 and 21.9–73.7 ppm, respectively. Mapping with 305 (96 SSRs; 208 DArT) markers detected seven linkage groups covering 1749 cM (Haldane) with an average intermarker distance of 5.73 cM. On the basis of two environment phenotypic data, two co-localized QTLs for Fe and Zn content on linkage group (LG) 3 were identified by composite interval mapping (CIM). Fe QTL explained 19% phenotypic variation, whereas the Zn QTL explained 36% phenotypic variation. Likewise for open pollinated seeds, the QTL analysis led to the identification of two QTLs for grain Fe content on LG3 and 5, and two QTLs for grain Zn content on LG3 and 7. The total phenotypic variance for Fe and Zn QTLs in open pollinated seeds was 16 and 42%, respectively. Analysis of QTL × QTL and QTL × QTL × environment interactions indicated no major epistasis. PMID:27933068

  2. Mapping presence and predicting phenological status of invasive buffelgrass in southern Arizona using MODIS, climate and citizen science observation data

    USGS Publications Warehouse

    Wallace, Cynthia S.A.; Walker, Jessica; Skirvin, Susan M.; Patrick-Birdwell, Caroline; Weltzin, Jake F.; Raichle, Helen

    2016-01-01

    The increasing spread and abundance of an invasive perennial grass, buffelgrass (Pennisetum ciliare), represents a critical threat to the native vegetation communities of the Sonoran desert in southern Arizona, USA, where buffelgrass eradication is a high priority for resource managers. Herbicidal treatment of buffelgrass is most effective when the vegetation is actively growing, but the remoteness of infestations and the erratic timing and length of the species’ growth periods confound effective treatment. The goal of our research is to promote buffelgrass management by using remote sensing data to detect where the invasive plants are located and when they are photosynthetically active. We integrated citizen scientist observations of buffelgrass phenology in the Tucson, Arizona area with PRISM precipitation data, eight-day composites of 250-m Moderate-resolution Imaging Spectroradiometer (MODIS) satellite imagery, and aerially-mapped polygons of buffelgrass presence to understand dynamics and relationships between precipitation and the timing and amount of buffelgrass greenness from 2011 to 2013. Our results show that buffelgrass responds quickly to antecedent rainfall: in pixels containing buffelgrass, higher correlations (R2 > 0.5) typically occur after two cumulative eight-day periods of rain, whereas in pixels dominated by native vegetation, four prior 8-day periods are required to reach that threshold. Using the new suite of phenometrics introduced here—Climate Landscape Response metrics—we accurately predicted the location of 49% to 55% of buffelgrass patches in Saguaro National Park. These metrics and the suggested guidelines for their use can be employed by resource managers to treat buffelgrass during optimal time periods.

  3. From Fireproof Desert to Flammable Grassland: Buffelgrass Invasion in the Sonoran Desert

    NASA Astrophysics Data System (ADS)

    Betancourt, J. L.

    2007-12-01

    Only a few decades ago, the Sonoran Desert of northwestern Mexico and southern Arizona was considered mostly fireproof, a case of not enough fine fuel to connect the dominant shrubs and cacti. This has changed with invasions by non-native, winter annual and summer-flower perennial grasses that are rapidly transforming fireproof desert into flammable grassland. Of particular concern is buffelgrass, Pennisetum ciliare, a fire-prone and invasive African perennial grass that has already converted millions of hectares across Sonora since the mid-1960s and has made quick headway in southern and central Arizona beginning in the 1980s. Near Tucson and Phoenix, AZ, buffelgrass invasion is proceeding exponentially, with population expansion (and the costs of mitigation) more than doubling every year. As this conversion progresses, there will be increased fire risks, lost tourist revenue, diminished property values, insurmountable setbacks to conservation efforts, and the threat of large ignition fronts in desert valleys routinely spreading into the mountains. Although somewhat belated, an integrated, multi-jurisdictional effort is being organized to reduce ecological and economic impacts. My presentation will summarize the history and context of buffelgrass introduction and invasion, the disconnect in attitudes and policies across state and international boundaries, ongoing management efforts, the role of science and responsibilities of scientists, accelerated spread with changing climate, and impacts to regional ecosystems and economies. This narrative may serve as a template for other semi-arid lands where buffelgrass and similar grasses have become invasive, including Australia, South America, and many islands in the Pacific Ocean (including Hawaii), Indian Ocean, and Caribbean Sea.

  4. Cochliotoxin, a Dihydropyranopyran-4,5-dione, and Its Analogues Produced by Cochliobolus australiensis Display Phytotoxic Activity against Buffelgrass (Cenchrus ciliaris).

    PubMed

    Masi, Marco; Meyer, Susan; Clement, Suzette; Cimmino, Alessio; Cristofaro, Massimo; Evidente, Antonio

    2017-05-26

    Buffelgrass (Pennisetum ciliare or Cenchrus ciliaris) is a perennial grass that has become highly invasive in the Sonoran Desert of southern Arizona. In the search for novel control strategies against this weed, strains of the foliar fungal pathogen Cochliobolus australiensis from buffelgrass have been screened for their ability to produce phytotoxic metabolites that could potentially be used as natural herbicides in an integrated pest management strategy. A new phytotoxin, named cochliotoxin, was isolated from liquid culture of this fungus together with radicinin, radicinol, and their 3-epimers. Cochliotoxin was characterized, essentially by spectroscopic methods, as 3-hydroxy-2-methyl-7-(3-methyloxiranyl)-2,3-dihydropyrano[4,3-b]pyran-4,5-dione. Its relative stereochemistry was assigned by 1 H NMR techniques, while the absolute configuration (2S,3S) was determined applying the advanced Mosher's method by esterification of its hydroxy group at C-3. When bioassayed in a buffelgrass coleoptile elongation test and by leaf puncture bioassay against the host weed and two nontarget grasses, cochliotoxin showed strong phytotoxicity. In the same tests, radicinin and 3-epi-radicinin also showed phytotoxic activity, while radicinol and 3-epi-radicinol were largely inactive. All five compounds were more active in leaf puncture bioassays on buffelgrass than on the nontarget grass tanglehead (Heteropogon contortus), while the nontarget grass Arizona cottontop (Digitaria californica) was more sensitive to radicinin and 3-epi-radicinin. Cochliotoxin at low concentration was significantly more active on buffelgrass than on either native grass, but the difference was small.

  5. Facilitative ecological interactions between invasive species: Arundo donax stands as favorable habitat for cattle ticks (Acari: Ixodidae) along the U.S.-Mexico border.

    PubMed

    Racelis, A E; Davey, R B; Goolsby, J A; Pérez de León, A A; Varner, K; Duhaime, R

    2012-03-01

    The cattle tick, Rhipicephalus (Boophilus) spp. is a key vector of protozoa that cause bovine babesiosis. Largely eradicated from most of the United States, the cattle tick continues to infest south Texas, and recent outbreaks in this area may signal a resurgence of cattle tick populations despite current management efforts. An improved understanding of the dynamic ecology of cattle fever ticks along the U.S.-Mexico border is required to devise strategies for sustainable eradication efforts. Management areas of the cattle tick overlap considerably with dense, wide infestations of the non-native, invasive grass known as giant reed (Arundo donax L.). Here we show that stands of giant reed are associated with abiotic and biotic conditions that are favorable to tick survival, especially when compared with other nearby habitats (open pastures of buffelgrass (Pennisetum ciliare) and closed canopy native forests). Overhead canopies in giant reed stands and native riparian forests reduce daily high temperature, which was the best abiotic predictor of oviposition by engorged females. In sites where temperatures were extreme, specifically open grasslands, fewer females laid eggs and the resulting egg masses were smaller. Pitfall trap collections of ground dwelling arthropods suggest a low potential for natural suppression of tick populations in giant reed stands. The finding that A. donax infestations present environmental conditions that facilitate the survival and persistence of cattle ticks, as well or better than native riparian habitats and open grasslands, represents an alarming complication for cattle fever tick management in the United States.

  6. Rheological properties of reduced fat ice cream mix containing octenyl succinylated pearl millet starch.

    PubMed

    Sharma, Monika; Singh, Ashish K; Yadav, Deep N

    2017-05-01

    The octenyl succinyl anhydride (OSA) esterified pearl millet ( Pennisetum typhoides ) starch was evaluated as fat replacer in soft serve ice cream in comparison to other fat replacers viz. inulin, whey protein concentrate-70 and commercial starch. During temperature sweep test, the yield stress and flow behaviour index of un-pasteurized ice cream mixes increased as the temperature increased from 40 to 80 °C, while the consistency index decreased. Consistency index of aged ice cream mixes containing 2% fat replacer was higher as compared to mixes with 1% level. The aged ice cream mixes exhibited non-Newtonian behaviour as flow behaviour index values were less than one. Apparent viscosity (at 50 s -1 shear rate) of control as well as ice cream mix containing 1% OSA-esterified pearl millet starch samples was 417 and 415 mPas, respectively and did not differ significantly. The overrun of the ice cream (with 5 and 7.5% fat) containing 1 and 2% of above fat replacers ranged between 29.7 and 34.3% and was significantly lower than control (40.3%). The percent melted ice cream was also low for the ice creams containing 2% of above fat replacers at 5% fat content as compared to control. However, sensory acceptability and rheological characteristics of reduced fat ice creams containing 1.0 and 2.0% OSA-esterified pearl millet starch were at par with other fat replacers under the study. Thus, OSA-esterified pearl millet starch has potential to be used as fat replacer in reduced fat ice cream.

  7. Role of plant growth regulators and a saprobic fungus in enhancement of metal phytoextraction potential and stress alleviation in pearl millet.

    PubMed

    Firdaus-e-Bareen; Shafiq, Muhammad; Jamil, Sidra

    2012-10-30

    "Assisted phytoextraction" involving application of chemical additives such as plant growth regulators (PGRs) has become a trend in phytoremediation technology. This study identifies a cost-effective, naturally available crude PGR (PGR1) that produces the same effects as the commercial PGR (PGR2), increasing metal uptake by plants and the reduction of metal stress. Assisted phytoextraction by pearl millet (Pennisetum glaucum) from a multi-metal (Cd, Cr, Cu, Fe, Na and Zn) contaminated soil medium with tannery solid waste (TSW) soil amendments of 5 and 10%, was evaluated in a full-factorial pot trial with PGR1, PGR2 and Trichoderma pseudokoningii as factors. The effects of these phytoextraction assistants were measured through dry biomass production, heavy metal uptake, stress tolerance enzymes catalase (CAT) and superoxide dismutase (SOD), soluble protein content of plant, and phytoextraction efficiency. Dry biomass and multi-metal accumulation were the highest in the soil treatments with a combined application of PGR1, PGR2 and T. pseudokoningii and the lowest in the control. The soluble protein contents and the SOD and CAT values were the highest in the 10% TSW treatment provided with PGR2+T. pseudokoningii, while the lowest were in the control. Thus, application of crude PGR in combination with other phytoextraction assistants can increase biomass production as well as multi-metal accumulation in plants. However, the biochemical properties of the plant depend on the level of TSW stress in the soil treatment as well as the type of phytoextraction assistants. Copyright © 2012 Elsevier B.V. All rights reserved.

  8. Effect of energy grass on methane production and heavy metal fractionation during anaerobic digestion of sewage sludge.

    PubMed

    Zhang, Min; Yang, Changming; Jing, Yachao; Li, Jianhua

    2016-12-01

    Anaerobic digestion (AD) is one of the most widely used processes to stabilize waste sewage sludge and produce biogas as renewable energy. The relatively low organic matter content and high heavy metal concentrations in sewage sludge have severely restricted the application and development of AD technology in China. In this study, the effect of energy grass (Pennisetum alopecuroides) addition on methane production and heavy metal fractionation during the AD of sewage sludge was evaluated. Methane production was enhanced by 11.2% by the addition of P. alopecuroides. The addition of P. alopecuroides significantly reduced the percentages of the water-soluble and exchangeable fractions of the target heavy metals in the sewage sludge after AD, and the dominant species were concentrated in Fe-Mn oxide-bound and organic- and sulfide-bound fractions of the digested sludge. The addition of P. alopecuroides at a dosage of 0.3kg significantly (P<0.05) decreased the mobility factors (MFs) of the target heavy metals after AD. In particular, the MFs of Cr and Ni were 61% and 32% lower, respectively, relative to the control. The increase in the added dose did not necessarily lead to further decreases in the MFs of the heavy metals. These results demonstrate that an appropriate addition of energy grass could enhance AD, decrease the mobility of heavy metals and promote heavy metal stabilization in sewage sludge during AD, which is beneficial for the subsequent land application of sewage sludge. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Association of Shifting Populations in the Root Zone Microbiome of Millet with Enhanced Crop Productivity in the Sahel Region (Africa)

    PubMed Central

    Assigbetse, Komi; Bayala, Roger; Chapuis-Lardy, Lydie; Dick, Richard P.; McSpadden Gardener, Brian B.

    2015-01-01

    This study characterized specific changes in the millet root zone microbiome stimulated by long-term woody-shrub intercropping at different sites in Senegal. At the two study sites, intercropping with woody shrubs and shrub residue resulted in a significant increase in millet [Pennisetum glaucum (L.) R. Br.] yield (P < 0.05) and associated patterns of increased diversity in both bacterial and fungal communities in the root zone of the crop. Across four experiments, operational taxonomic units (OTUs) belonging to Chitinophaga were consistently significantly (P < 0.001) enriched in the intercropped samples, and “Candidatus Koribacter” was consistently significantly enriched in samples where millet was grown alone. Those OTUs belonging to Chitinophaga were enriched more than 30-fold in residue-amended samples and formed a distinct subgroup from all OTUs detected in the genus. Additionally, OTUs belonging to 8 fungal genera (Aspergillus, Coniella, Epicoccum, Fusarium, Gibberella, Lasiodiplodia, Penicillium, and Phoma) were significantly (P < 0.005) enriched in all experiments at all sites in intercropped samples. The OTUs of four genera (Epicoccum, Fusarium, Gibberella, and Haematonectria) were consistently enriched at sites where millet was grown alone. Those enriched OTUs in intercropped samples showed consistently large-magnitude differences, ranging from 30- to 1,000-fold increases in abundance. Consistently enriched OTUs in intercropped samples in the genera Aspergillus, Fusarium, and Penicillium also formed phylogenetically distinct subgroups. These results suggest that the intercropping system used here can influence the recruitment of potentially beneficial microorganisms to the root zone of millet and aid subsistence farmers in producing higher-yielding crops. PMID:25681183

  10. The dynamics of LTR retrotransposon accumulation across 25 million years of panicoid grass evolution

    PubMed Central

    Estep, M C; DeBarry, J D; Bennetzen, J L

    2013-01-01

    Sample sequence analysis was employed to investigate the repetitive DNAs that were most responsible for the evolved variation in genome content across seven panicoid grasses with >5-fold variation in genome size and different histories of polyploidy. In all cases, the most abundant repeats were LTR retrotransposons, but the particular families that had become dominant were found to be different in the Pennisetum, Saccharum, Sorghum and Zea lineages. One element family, Huck, has been very active in all of the studied species over the last few million years. This suggests the transmittal of an active or quiescent autonomous set of Huck elements to this lineage at the founding of the panicoids. Similarly, independent recent activity of Ji and Opie elements in Zea and of Leviathan elements in Sorghum and Saccharum species suggests that members of these families with exceptional activation potential were present in the genome(s) of the founders of these lineages. In a detailed analysis of the Zea lineage, the combined action of several families of LTR retrotransposons were observed to have approximately doubled the genome size of Zea luxurians relative to Zea mays and Zea diploperennis in just the last few million years. One of the LTR retrotransposon amplification bursts in Zea may have been initiated by polyploidy, but the great majority of transposable element activations are not. Instead, the results suggest random activation of a few or many LTR retrotransposons families in particular lineages over evolutionary time, with some families especially prone to future activation and hyper-amplification. PMID:23321774

  11. Soil Organic Matter Quality of an Oxisol Affected by Plant Residues and Crop Sequence under No-Tillage

    NASA Astrophysics Data System (ADS)

    Cora, Jose; Marcelo, Adolfo

    2013-04-01

    Plant residues are considered the primarily resource for soil organic matter (SOM) formation and the amounts and properties of plant litter are important controlling factors for the SOM quality. We determined the amounts, quality and decomposition rate of plant residues and the effects of summer and winter crop sequences on soil organic C (TOC) content, both particulate organic C (POC) and mineral-associated organic C (MOC) pools and humic substances in a Brazilian Rhodic Eutrudox soil under a no-tillage system. The organic C analysis in specifics pools used in this study was effective and should be adopted in tropical climates to evaluate the soil quality and the sustainability of various cropping systems. Continuous growth of soybean (Glycine max L. Merrill) on summer provided higher contents of soil POC and continuous growth of maize (Zea mays L.) provided higher soil humic acid and MOC contents. Summer soybean-maize rotation provided the higher plant diversity, which likely improved the soil microbial activity and the soil organic C consumption. The winter sunn hemp (Crotalaria juncea L.), pigeon pea (Cajanus cajan (L.) Millsp), oilseed radish (Raphanus sativus L.) and pearl millet (Pennisetum americanum (L.) Leeke) enhanced the soil MOC, a finding that is attributable to the higher N content of the crop residue. Sunn hemp and pigeon pea provided the higher soil POC content. Sunn hemp showed better performance and positive effects on the SOM quality, making it a suitable winter crop choice for tropical conditions with a warm and dry winter.

  12. Soil tillage and windbreak effects on millet and cowpea: I. Wind speed, evaporation, and wind erosion

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Banzhaf, J.; Leihner, D.E.; Buerkert, A.

    Deforestation, overgrazing, and declining soil regeneration periods have resulted in increased wind erosion problems in dry areas of the West African Sahel, but little is known about the bio-physical factors involved. This research was conducted to determine the effects of ridging and four different windbreak spacings on wind erosion, potential evaporation, and soil water reserves. A field trial was conducted from 1985 to 1987 on 12 ha of a Psammentic Paleustalf in Southern Niger. Millet, Pennisetum glaucum (L.), and cowpea, Vigna unguiculata (L.) Walp., were seeded in strips on flat and ridged soil. Windbreaks of savannah vegetation were spaced atmore » 6, 20, 40, and 90 m. The effects of ridging on wind speed, evaporation, and wind erosion were small and mostly non-significant. However, average wind speed at 0.3 m above ground in the center of cowpea and millet strips was significantly reduced from 2.8 to 2.1 m s[sup [minus]1] as windbreak distances narrowed from 90 to 6 m. As a consequence, potential evaporation declined by 15% and the amount of windblown soil particles by 50% in ridged and by 70% in flat treatments. Despite reduced potential evaporation, average subsoil water reserves were 14 mm smaller in the 6- than in the 20-m windbreak spacing indicating excessive water extraction by the windbreak vegetation. Thus, establishing windbreaks with natural savannah vegetation may require a careful consideration of the agronomic benefits and costs to competing crops. 21 refs., 5 figs.« less

  13. Simulated Optimum Sowing Date for Forage Pearl Millet Cultivars in Multilocation Trials in Brazilian Semi-Arid Region.

    PubMed

    Santos, Rafael D; Boote, Kenneth J; Sollenberger, Lynn E; Neves, Andre L A; Pereira, Luiz G R; Scherer, Carolina B; Gonçalves, Lucio C

    2017-01-01

    Forage production is primarily limited by weather conditions under dryland production systems in Brazilian semi-arid regions, therefore sowing at the appropriate time is critical. The objectives of this study were to evaluate the CSM-CERES-Pearl Millet model from the DSSAT software suite for its ability to simulate growth, development, and forage accumulation of pearl millet [ Pennisetum glaucum (L.) R.] at three Brazilian semi-arid locations, and to use the model to study the impact of different sowing dates on pearl millet performance for forage. Four pearl millet cultivars were grown during the 2011 rainy season in field experiments conducted at three Brazilian semi-arid locations, under rainfed conditions. The genetic coefficients of the four pearl millet cultivars were calibrated for the model, and the model performance was evaluated with experimental data. The model was run for 14 sowing dates using long-term historical weather data from three locations, to determine the optimum sowing window. Results showed that performance of the model was satisfactory as indicated by accurate simulation of crop phenology and forage accumulation against measured data. The optimum sowing window varied among locations depending on rainfall patterns, although showing the same trend for cultivars within the site. The best sowing windows were from 15 April to 15 May for the Bom Conselho location; 12 April to 02 May for Nossa Senhora da Gloria; and 17 April to 25 May for Sao Bento do Una. The model can be used as a tool to evaluate the effect of sowing date on forage pearl millet performance in Brazilian semi-arid conditions.

  14. Applicability of leachates originating from solid-waste landfills for irrigation in landfill restoration projects.

    PubMed

    Erdogan, Reyhan; Zaimoglu, Zeynep; Sucu, M Yavuz; Budak, Fuat; Kekec, Secil

    2008-09-01

    Since, landfill areas are still the most widely used solid waste disposal method across the world, leachate generated from landfills should be given importance. Leachate of landfills exerts environmental risks mostly on surface and groundwater with its high pollutant content, which may cause unbearable water quality. This leads to the obligation for decontamination and remediation program to be taken into progress for the landfill area. Among a number of alternatives to cope with leachate, one is to employ the technology of phytoremediation. The main objective of this study was to determine the N accumulation ratios and the effects of landfill leachate in diluted proportions of chosen ratios (as 1/1, 1/2, 1/4, 0), on the growth and development of Cynodon dactylon, Stenotaphrum secundatum, Paspalum notatum, Pennisetum clandestinum, Mentha piperita, Rosmarinus officinalis, Nerium oleander, Pelargonium peltatum and Kochia scoparia species. In order to simulate the actual conditions of the landfill, soil covering the landfill is taken and used as medium for the trials. The study showed that S. secundatum, K. scoparia and N. oleander species had an impressive survival rate of 100%, being irrigated with pure leachate, while the others' survival rates were between 0 to 35% under the same conditions. As expected, application of leachate to the plants caused an increase in the accumulation of N, in the upper parts of all plants except P. peltatum. The highest N content increase was observed at S. Secundatum set, accumulating 3.70 times higher than its control set, whereas P. clandestinum value was 3.41 times of its control set.

  15. Dry forest restoration and unassisted native tree seedling recruitment at Auwahi, Maui

    USGS Publications Warehouse

    Medeiros, Arthur C.; von Allmen, E. I.; Chimera, C.G.

    2014-01-01

    Efforts to restore highly degraded but biologically significant forests draw from a limited toolbox. With less than 10% of their former distribution remaining, Hawaiian dry forests, though critically endangered, remain important biological and cultural refugia. At restoration onset (1997), vegetation of restoration and control areas of degraded Auwahi dry forest, Maui Island, was similar, dominated by nonnative graminoids (restoration 78.3%; control 75.4%), especially Cenchrus (Pennisetum) clandestinus. In 2012, unrestored control area vegetation was basically unchanged. In contrast, in the restoration area in 2012, native shrub cover increased from 3.1% to 81.9%, and cover of nonnative graminoids declined from 75.4% to 3.3%. In 2012, nonplanted seedlings of 14 of 22 native tree species and six of seven native shrub species were observed in restoration plots; the majority (99%) were five native (Dodonaea viscosa, Coprosma foliosa, Osteomeles anthyllidifolia, Chamaesyce celastoides, Nestegis sandwicensis) and one nonnative species (Bocconia frutescens). By 2012, stem counts of native woody plants had increased from 12.4 to 135.0/100 m2, and native species diversity increased from 2.4 to 6.6/100 m2. By 2012, seven rare dry forest tree species, Charpentiera obovata, Nothocestrum latifolium, Ochrosia haleakalae, Pleomele auwahiensis, Santalum ellipticum, S. haleakalae, and Streblus pendulinus, had established seedlings and/or saplings within the restoration site, especially notable because natural reproduction is largely lacking elsewhere. Without development and implementation of appropriate management strategies, remaining Hawaiian dry forest will likely disappear within the next century. Multicomponent restoration incorporating ungulate exclusion, weed control, and outplanting as described here offers one strategy to conserve and restore tracts of high-value but degraded forests.

  16. Total Iron Absorption by Young Women from Iron-Biofortified Pearl Millet Composite Meals Is Double That from Regular Millet Meals but Less Than That from Post-Harvest Iron-Fortified Millet Meals123

    PubMed Central

    Cercamondi, Colin I.; Egli, Ines M.; Mitchikpe, Evariste; Tossou, Felicien; Zeder, Christophe; Hounhouigan, Joseph D.; Hurrell, Richard F.

    2013-01-01

    Iron biofortification of pearl millet (Pennisetum glaucum) is a promising approach to combat iron deficiency (ID) in the millet-consuming communities of developing countries. To evaluate the potential of iron-biofortified millet to provide additional bioavailable iron compared with regular millet and post-harvest iron-fortified millet, an iron absorption study was conducted in 20 Beninese women with marginal iron status. Composite test meals consisting of millet paste based on regular-iron, iron-biofortified, or post-harvest iron-fortified pearl millet flour accompanied by a leafy vegetable sauce or an okra sauce were fed as multiple meals for 5 d. Iron absorption was measured as erythrocyte incorporation of stable iron isotopes. Fractional iron absorption from test meals based on regular-iron millet (7.5%) did not differ from iron-biofortified millet meals (7.5%; P = 1.0), resulting in a higher quantity of total iron absorbed from the meals based on iron-biofortified millet (1125 vs. 527 μg; P < 0.0001). Fractional iron absorption from post-harvest iron-fortified millet meals (10.4%) was higher than from regular-iron and iron-biofortified millet meals (P < 0.05 and P < 0.01, respectively), resulting in a higher quantity of total iron absorbed from the post-harvest iron-fortified millet meals (1500 μg; P < 0.0001 and P < 0.05, respectively). Results indicate that consumption of iron-biofortified millet would double the amount of iron absorbed and, although fractional absorption of iron from biofortification is less than that from fortification, iron-biofortified millet should be highly effective in combatting ID in millet-consuming populations. PMID:23884388

  17. Silage review: Unique challenges of silages made in hot and cold regions.

    PubMed

    Bernardes, T F; Daniel, J L P; Adesogan, A T; McAllister, T A; Drouin, P; Nussio, L G; Huhtanen, P; Tremblay, G F; Bélanger, G; Cai, Y

    2018-05-01

    Silage making can be conveniently divided into field, ensiling, storage, and feed-out phases. In all of these stages, controllable and uncontrollable components can affect silage quality. For instance, silages produced in hot or cold regions are strongly influenced by uncontrollable climate-related factors. In hot regions, crops for silage are influenced by (1) high temperatures negatively affecting corn yield (whole-crop and grain) and nutritive value, (2) butyric and alcoholic fermentations in warm-season grasses (Panicum, Brachiaria, and Pennisetum genera) and sugarcane, respectively, and (3) accelerated aerobic deterioration of silages. Ensiling expertise and economic factors that limit mechanization also impair silage production and utilization in hot environments. In cold regions, a short and cool growing season often limits the use of crops sensitive to cool temperature, such as corn. The fermentation triggered by epiphytic and inoculated microorganisms can also be functionally impaired at lower temperature. Although the use of silage inoculants has increased in Northern Europe, acid-based additives are still a good option in difficult weather conditions to ensure good fermentation quality, nutritive value, and high intake potential of silages. Acid-based additives have enhanced the quality of round bale silage, which has become a common method of forage preservation in Northern Europe. Although all abiotic factors can affect silage quality, the ambient temperature is a factor that influences all stages of silage making from production in the field to utilization at the feed bunk. This review identifies challenges and obstacles to producing silages under hot and cold conditions and discusses strategies for addressing these challenges. Copyright © 2018 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  18. A Parthenogenesis Gene Candidate and Evidence for Segmental Allopolyploidy in Apomictic Brachiaria decumbens

    PubMed Central

    Worthington, Margaret; Heffelfinger, Christopher; Bernal, Diana; Quintero, Constanza; Zapata, Yeny Patricia; Perez, Juan Guillermo; De Vega, Jose; Miles, John; Dellaporta, Stephen; Tohme, Joe

    2016-01-01

    Apomixis, asexual reproduction through seed, enables breeders to identify and faithfully propagate superior heterozygous genotypes by seed without the disadvantages of vegetative propagation or the expense and complexity of hybrid seed production. The availability of new tools such as genotyping by sequencing and bioinformatics pipelines for species lacking reference genomes now makes the construction of dense maps possible in apomictic species, despite complications including polyploidy, multisomic inheritance, self-incompatibility, and high levels of heterozygosity. In this study, we developed saturated linkage maps for the maternal and paternal genomes of an interspecific Brachiaria ruziziensis (R. Germ. and C. M. Evrard) × B. decumbens Stapf. F1 mapping population in order to identify markers linked to apomixis. High-resolution molecular karyotyping and comparative genomics with Setaria italica (L.) P. Beauv provided conclusive evidence for segmental allopolyploidy in B. decumbens, with strong preferential pairing of homologs across the genome and multisomic segregation relatively more common in chromosome 8. The apospory-specific genomic region (ASGR) was mapped to a region of reduced recombination on B. decumbens chromosome 5. The Pennisetum squamulatum (L.) R.Br. PsASGR-BABY BOOM-like (psASGR–BBML)-specific primer pair p779/p780 was in perfect linkage with the ASGR in the F1 mapping population and diagnostic for reproductive mode in a diversity panel of known sexual and apomict Brachiaria (Trin.) Griseb. and P. maximum Jacq. germplasm accessions and cultivars. These findings indicate that ASGR–BBML gene sequences are highly conserved across the Paniceae and add further support for the postulation of the ASGR–BBML as candidate genes for the apomictic function of parthenogenesis. PMID:27206716

  19. A Parthenogenesis Gene Candidate and Evidence for Segmental Allopolyploidy in Apomictic Brachiaria decumbens.

    PubMed

    Worthington, Margaret; Heffelfinger, Christopher; Bernal, Diana; Quintero, Constanza; Zapata, Yeny Patricia; Perez, Juan Guillermo; De Vega, Jose; Miles, John; Dellaporta, Stephen; Tohme, Joe

    2016-07-01

    Apomixis, asexual reproduction through seed, enables breeders to identify and faithfully propagate superior heterozygous genotypes by seed without the disadvantages of vegetative propagation or the expense and complexity of hybrid seed production. The availability of new tools such as genotyping by sequencing and bioinformatics pipelines for species lacking reference genomes now makes the construction of dense maps possible in apomictic species, despite complications including polyploidy, multisomic inheritance, self-incompatibility, and high levels of heterozygosity. In this study, we developed saturated linkage maps for the maternal and paternal genomes of an interspecific Brachiaria ruziziensis (R. Germ. and C. M. Evrard) × B. decumbens Stapf. F1 mapping population in order to identify markers linked to apomixis. High-resolution molecular karyotyping and comparative genomics with Setaria italica (L.) P. Beauv provided conclusive evidence for segmental allopolyploidy in B. decumbens, with strong preferential pairing of homologs across the genome and multisomic segregation relatively more common in chromosome 8. The apospory-specific genomic region (ASGR) was mapped to a region of reduced recombination on B. decumbens chromosome 5. The Pennisetum squamulatum (L.) R.Br. PsASGR-BABY BOOM-like (psASGR-BBML)-specific primer pair p779/p780 was in perfect linkage with the ASGR in the F1 mapping population and diagnostic for reproductive mode in a diversity panel of known sexual and apomict Brachiaria (Trin.) Griseb. and P. maximum Jacq. germplasm accessions and cultivars. These findings indicate that ASGR-BBML gene sequences are highly conserved across the Paniceae and add further support for the postulation of the ASGR-BBML as candidate genes for the apomictic function of parthenogenesis. Copyright © 2016 by the Genetics Society of America.

  20. [Effects of highway on the vegetation species composition along a distance gradient from road edge in southeastern margin of Tengeer Desert].

    PubMed

    Feng, Li; Li, Xin-Rong; Guo, Qun; Zhang, Jing-Guang; Zhang, Zhi-Shan

    2011-05-01

    Aimed to examine the effects of highway on the vegetation species composition in arid desert area, forty-eight transects perpendicular to the provincial highway 201 from Shapotou to Jing-tai in the southeastern margin of Tengger Desert were installed, with the vegetation species distribution along a distance gradient from the road edge investigated. The results showed that with increasing distance from the road edge, the species number, coverage, biomass, and alpha-diversity of herbaceous plants declined, but had no significant differences with the control beyond 5 m. Within 0-6 m to the road edge, the herbaceous plant height was greater than that of the control, but their density had less change. Within 0-2 m to the road edge, the species turnover rate of herbaceous plants was lower; at 2-5m, this rate was the highest; while beyond 10 m, the species composition of herbaceous plants was similar to that of the control. The herbaceous plant community at the road edge was dominated by gramineous plants, with the disturbance-tolerant species Pennisetum centrasiaticum, Chloris virgata, and Agropyron cristatum accounting for 68.6% of the total. C. virgata beyond 1 m to the road edge had a rapid decrease in its individual number and presence frequency, P. centrasiaticum and A. cristatum beyond 2 m also showed a similar trend, while the composite plants Artemisia capillaris and A. frigida beyond 2 m from the road edge had a rapid increase in its individual number, accounting for 70% of the herbaceous plants. At the road edge, the coverage and density of shrubs were significantly lower than those of the control, but the species composition had no significant difference.

  1. Ectoparasitic growth of Magnaporthe on barley triggers expression of the putative barley wax biosynthesis gene CYP96B22 which is involved in penetration resistance

    PubMed Central

    2014-01-01

    Background Head blast caused by the fungal plant pathogen Magnaporthe oryzae is an upcoming threat for wheat and barley cultivation. We investigated the nonhost response of barley to an isolate of the Magnaporthe species complex which is pathogenic on Pennisetum spp. as a potential source for novel resistance traits. Results Array experiments identified a barley gene encoding a putative cytochrome P450 monooxygenase whose transcripts accumulate to a higher concentration in the nonhost as compared to the host interaction. The gene clusters within the CYP96 clade of the P450 plant gene family and is designated as CYP96B22. Expression of CYP96B22 was triggered during the ectoparasitic growth of the pathogen on the outside of the leaf. Usage of a fungicidal treatment and a Magnaporthe mutant confirmed that penetration was not necessary for this early activation of CYP96B22. Transcriptional silencing of CYP96B22 using Barley stripe mosaic virus led to a decrease in penetration resistance of barley plants to Magnaporthe host and nonhost isolates. This phenotype seems to be specific for the barley-Magnaporthe interaction, since penetration of the adapted barley powdery mildew fungus was not altered in similarly treated plants. Conclusion Taken together our results suggest a cross-talk between barley and Magnaporthe isolates across the plant surface. Since members of the plant CYP96 family are known to be involved in synthesis of epicuticular waxes, these substances or their derivatives might act as signal components. We propose a functional overlap of CYP96B22 in the execution of penetration resistance during basal and nonhost resistance of barley against different Magnaporthe species. PMID:24423145

  2. A new phenotyping pipeline reveals three types of lateral roots and a random branching pattern in two cereals.

    PubMed

    Passot, Sixtine; Moreno-Ortega, Beatriz; Moukouanga, Daniel; Balsera, Crispulo; Guyomarc'h, Soazig; Lucas, Mikael; Lobet, Guillaume; Laplaze, Laurent; Muller, Bertrand; Guédon, Yann

    2018-05-11

    Recent progress in root phenotyping has focused mainly on increasing throughput for genetic studies while identifying root developmental patterns has been comparatively underexplored. We introduce a new phenotyping pipeline for producing high-quality spatio-temporal root system development data and identifying developmental patterns within these data. The SmartRoot image analysis system and temporal and spatial statistical models were applied to two cereals, pearl millet (Pennisetum glaucum) and maize (Zea mays). Semi-Markov switching linear models were used to cluster lateral roots based on their growth rate profiles. These models revealed three types of lateral roots with similar characteristics in both species. The first type corresponds to fast and accelerating roots, the second to rapidly arrested roots, and the third to an intermediate type where roots cease elongation after a few days. These types of lateral roots were retrieved in different proportions in a maize mutant affected in auxin signaling, while the first most vigorous type was absent in maize plants exposed to severe shading. Moreover, the classification of growth rate profiles was mirrored by a ranking of anatomical traits in pearl millet. Potential dependencies in the succession of lateral root types along the primary root were then analyzed using variable-order Markov chains. The lateral root type was not influenced by the shootward neighbor root type or by the distance from this root. This random branching pattern of primary roots was remarkably conserved, despite the high variability of root systems in both species. Our phenotyping pipeline opens the door to exploring the genetic variability of lateral root developmental patterns. {copyright, serif} 2018 American Society of Plant Biologists. All rights reserved.

  3. Antinutritional factors in pearl millet grains: Phytate and goitrogens content variability and molecular characterization of genes involved in their pathways

    PubMed Central

    Gangashetty, Prakash Irappa; Grando, Stefania; Kwaku Zu, Theophilus Tenutse; Daminati, Maria Gloria

    2018-01-01

    Pearl millet [Pennisetum glaucum (L.) R. Br.] is an important “orphan” cereal and the most widely grown of all the millet species worldwide. It is also the sixth most important cereal in the world after wheat, rice, maize, barley, and sorghum, being largely grown and used in West Africa as well as in India and Pakistan. The present study was carried out in the frame of a program designed to increase benefits and reduce potential health problems deriving from the consumption of pearl millet. The specific goal was to provide a database of information on the variability existing in pearl millet germplasm as to the amounts of phytate, the most relevant antinutrient compound, and the goitrogenic compounds C-glycosylflavones (C-GFs) accumulated in the grain.Results we obtained clearly show that, as indicated by the range in values, a substantial variability subsists across the investigated pearl millet inbred lines as regards the grain level of phytic acid phosphate, while the amount of C-GFs shows a very high variation. Suitable potential parents to be used in breeding programs can be therefore chosen from the surveyed material in order to create new germplasm with increased nutritional quality and food safety. Moreover, we report novel molecular data showing which genes are more relevant for phytic acid biosynthesis in the seeds as well as a preliminary analysis of a pearl millet orthologous gene for C-GFs biosynthesis. These results open the way to dissect the genetic determinants controlling key seed nutritional phenotypes and to the characterization of their impact on grain nutritional value in pearl millet. PMID:29856884

  4. Simulated Optimum Sowing Date for Forage Pearl Millet Cultivars in Multilocation Trials in Brazilian Semi-Arid Region

    PubMed Central

    Santos, Rafael D.; Boote, Kenneth J.; Sollenberger, Lynn E.; Neves, Andre L. A.; Pereira, Luiz G. R.; Scherer, Carolina B.; Gonçalves, Lucio C.

    2017-01-01

    Forage production is primarily limited by weather conditions under dryland production systems in Brazilian semi-arid regions, therefore sowing at the appropriate time is critical. The objectives of this study were to evaluate the CSM-CERES-Pearl Millet model from the DSSAT software suite for its ability to simulate growth, development, and forage accumulation of pearl millet [Pennisetum glaucum (L.) R.] at three Brazilian semi-arid locations, and to use the model to study the impact of different sowing dates on pearl millet performance for forage. Four pearl millet cultivars were grown during the 2011 rainy season in field experiments conducted at three Brazilian semi-arid locations, under rainfed conditions. The genetic coefficients of the four pearl millet cultivars were calibrated for the model, and the model performance was evaluated with experimental data. The model was run for 14 sowing dates using long-term historical weather data from three locations, to determine the optimum sowing window. Results showed that performance of the model was satisfactory as indicated by accurate simulation of crop phenology and forage accumulation against measured data. The optimum sowing window varied among locations depending on rainfall patterns, although showing the same trend for cultivars within the site. The best sowing windows were from 15 April to 15 May for the Bom Conselho location; 12 April to 02 May for Nossa Senhora da Gloria; and 17 April to 25 May for Sao Bento do Una. The model can be used as a tool to evaluate the effect of sowing date on forage pearl millet performance in Brazilian semi-arid conditions. PMID:29276521

  5. A feasibility study of perennial/annual plant species to restore soils contaminated with heavy metals

    NASA Astrophysics Data System (ADS)

    Zacarías, Montserrat; Beltrán, Margarita; Gilberto Torres, Luis; González, Abelardo

    A feasibility study was carried out to evaluate the application of perennial/annual plant species in a phytoextraction process of a previously washed industrial urban soil contaminated by nickel, arsenic and cupper. The plant species selected for this study were Ipomea (Ipomea variada); grass (Poa pratensis); grass mixture (Festuca rubra, Cynodon dactylon, Lolium multiforum, Pennisetum sp.); Monks Cress (Tropaeolum majus); ficus (Ficus benajamina) and fern (Pteris cretica). Soil was characterized and it presented the following heavy metals concentrations (dry weight): 80 mg of Ni/kg, 456-656 mg of As/kg and 1684-3166 mg of Cu/kg. Germination and survival in contaminated soil tests were conducted, from these, P. pratensis was discarded and the rest of plant species tested were used for the phytoextraction selection test. After 4 months of growth, biomass production was determined, and content of Ni, As and Cu was analyzed in plant’s tissue. Metal biological absorption coefficient (BAC), bio-concentration factor (BCF) and translocation factor (TF), were calculated. Regarding to biomass generation it was observed, in every case, an inhibition of the plant growth compared with blanks sown in a non contaminated soil; inhibition ranged from 22.5% for the Monk cress to 98% for Ipomea. Even though the later presented high BAC, BCF and TF, its growth was severely inhibited, and therefore, due its low biomass generation, it is not recommended for phytoextraction under conditions for this study. Heavy metals concentrations in plant’s tissue (dry weight) were as high as 866 mg Cu/kg and 602 mg As/kg for grass mixture; and 825 mg As/kg was observed for Monks cress. Grass mixture and monks cress had high BAC, BCF and TF, also they had high metal concentrations in its plants tissues and the lowest growth inhibition rates; hence the application in phytoextraction processes of these plants is advisable.

  6. Predicting Treatment Windows for Invasive Buffelgrass in Southern Arizona using MODIS and Climate Data

    NASA Astrophysics Data System (ADS)

    Wallace, C.; Weltzin, J. F.; Skirvin, S. M.; Patrick-Birdwell, C.; Raichle, H.

    2014-12-01

    The increasing spread and abundance of an invasive perennial grass, buffelgrass (Pennisetum ciliare), represents an important shift in the vegetation composition of the Sonoran Desert in southern Arizona. Buffelgrass out-competes native species and alters fire regimes, and its control and management is a high-priority issue for resource managers who seek to preserve the unique and iconic Sonoran Desert flora. Herbicidal treatment of buffelgrass is most effective when the vegetation is actively growing; however, the erratic timing and length of active buffelgrass growth periods in southern Arizona confound effective management decision-making. The goal of our research is to enable the strategic application of buffelgrass herbicide by using remote sensing data to detect when and where buffelgrass is photosynthetically active. We integrated ground-based observations of buffelgrass phenology (green-up and senescence) in the Tucson, Arizona area with climate information and Moderate-resolution Imaging Spectroradiometer (MODIS) satellite imagery at 250m spatial and both 8-day and 16-day composite temporal resolution to understand dynamics, relationships and resonance between these disparate datasets during 2011 to 2013. Fourier harmonics analysis was used to derive land surface phenology (LSP) metrics from MODIS Enhanced Vegetation Index (EVI) greenness data and to quantify the temporal patterns of the climate and phenophase abundance datasets. Regression analyses and statistical tests were used to identify correlations between temporal patterns of the data sets. Our results reveal strong correlations between the observed greenness of in-situ buffelgrass and satellite LSP metrics, confirming that MODIS-EVI data can be a useful indicator of active buffelgrass growth at multiple scales. The analysis also reveals strong harmonics between precipitation and greenness, but with a lagged response, suggesting that precipitation can be a predictor of the location and intensity of

  7. Exogenous Trehalose Treatment Enhances the Activities of Defense-Related Enzymes and Triggers Resistance against Downy Mildew Disease of Pearl Millet.

    PubMed

    Govind, Sharathchandra R; Jogaiah, Sudisha; Abdelrahman, Mostafa; Shetty, Hunthrike S; Tran, Lam Son P

    2016-01-01

    In recent years, diverse physiological functions of various sugars are the subject of investigations. Their roles in signal transduction in plant responses to adverse biotic and abiotic stress conditions have become apparent, and growing scientific evidence has indicated that disaccharides like sucrose and trehalose mediate plant defense responses in similar way as those induced by elicitors against the pathogens. Trehalose is a well-known metabolic osmoregulator, stress-protectant and non-reducing disaccharide existing in a variety of organisms, including fungi, bacteria, and plants. Commercially procured trehalose was applied to seeds of susceptible pearl millet ( Pennisetum glaucum ) cultivar "HB3," and tested for its ability to reduce downy mildew disease incidence by induction of resistance. Seed treatment with trehalose at 200 mM for 9 h recorded 70.25% downy mildew disease protection, followed by those with 100 and 50 mM trehalose which offered 64.35 and 52.55% defense, respectively, under greenhouse conditions. Furthermore, under field conditions treatment with 200 mM trehalose for 9 h recorded 67.25% downy mildew disease protection, and reduced the disease severity to 32.75% when compared with untreated control which displayed 90% of disease severity. Trehalose did not affect either sporangial formation or zoospore release from sporangia, indicating that the reduction in disease incidence was not due to direct inhibition but rather through induction of resistance responses in the host. Additionally, trehalose was shown to enhance the levels of polyphenol oxidase, phenylalanine ammonia lyase, and peroxidase, which are known as markers of both biotic and abiotic stress responses. Our study shows that osmoregulators like trehalose could be used to protect plants against pathogen attacks by seed treatment, thus offering dual benefits of biotic and abiotic stress tolerance.

  8. Exogenous Trehalose Treatment Enhances the Activities of Defense-Related Enzymes and Triggers Resistance against Downy Mildew Disease of Pearl Millet

    PubMed Central

    Govind, Sharathchandra R.; Jogaiah, Sudisha; Abdelrahman, Mostafa; Shetty, Hunthrike S.; Tran, Lam-Son P.

    2016-01-01

    In recent years, diverse physiological functions of various sugars are the subject of investigations. Their roles in signal transduction in plant responses to adverse biotic and abiotic stress conditions have become apparent, and growing scientific evidence has indicated that disaccharides like sucrose and trehalose mediate plant defense responses in similar way as those induced by elicitors against the pathogens. Trehalose is a well-known metabolic osmoregulator, stress-protectant and non-reducing disaccharide existing in a variety of organisms, including fungi, bacteria, and plants. Commercially procured trehalose was applied to seeds of susceptible pearl millet (Pennisetum glaucum) cultivar “HB3,” and tested for its ability to reduce downy mildew disease incidence by induction of resistance. Seed treatment with trehalose at 200 mM for 9 h recorded 70.25% downy mildew disease protection, followed by those with 100 and 50 mM trehalose which offered 64.35 and 52.55% defense, respectively, under greenhouse conditions. Furthermore, under field conditions treatment with 200 mM trehalose for 9 h recorded 67.25% downy mildew disease protection, and reduced the disease severity to 32.75% when compared with untreated control which displayed 90% of disease severity. Trehalose did not affect either sporangial formation or zoospore release from sporangia, indicating that the reduction in disease incidence was not due to direct inhibition but rather through induction of resistance responses in the host. Additionally, trehalose was shown to enhance the levels of polyphenol oxidase, phenylalanine ammonia lyase, and peroxidase, which are known as markers of both biotic and abiotic stress responses. Our study shows that osmoregulators like trehalose could be used to protect plants against pathogen attacks by seed treatment, thus offering dual benefits of biotic and abiotic stress tolerance. PMID:27895647

  9. Grass Pollen Affects Survival and Development of Larval Anopheles arabiensis (Diptera: Culicidae).

    PubMed

    Asmare, Yelfwagash; Hopkins, Richard J; Tekie, Habte; Hill, Sharon R; Ignell, Rickard

    2017-09-01

    Nutrients in breeding sites are critical for the survival and development of malaria mosquitoes, having a direct impact on vectorial capacity. Yet, there is a limited understanding about the natural larval diet and its impact on the individual fitness of mosquitoes. Recent studies have shown that gravid Anopheles arabiensis Patton (Diptera: Culicidae) are attracted by and oviposit in grass-associated habitats. The pollen provided by these grasses is a potential source of nutrients for the larvae. Here, we assess the effect of Typha latifolia L. (Poales: Typhaceae), Echinochloa pyramidalis Lamarck, Pennisetum setaceum Forsskål, and Zea mays L. pollen on larval survival and rate of development in An. arabiensis under laboratory conditions. In addition, we characterize the carbon to nitrogen ratio and the size of pollen grains as a measure of diet quality. Carbon-rich pollen with a small grain size (T. latifolia and P. setaceum; 9.7 ± 0.3 × 103 and 5.5 ± 0.2 × 104 µm3, respectively) resulted in enhanced rates of development of An. arabiensis. In contrast, the larva fed on the nitrogen-rich control diet (TetraMin) was slower to develop, but demonstrated the highest larval survival. Larvae fed on carbon-rich and large-grained Z. mays pollen (4.1 ± 0.2 × 105 µm3) survived at similar levels as those fed on the control diet and also took a longer time to develop compared with larvae fed on the other pollens. While males and females did not appear to develop differently on the different pollen diets, males consistently emerged faster than their female counterparts. These results are discussed in relation to integrated vector management. © The Author 2017. Published by Oxford University Press on behalf of Entomological Society of America.

  10. Simulating long-term effectiveness and efficiency of management scenarios for an invasive grass

    USGS Publications Warehouse

    Jarnevich, Catherine S.; Holcombe, Tracy R.; Cullinane Thomas, Catherine; Frid, Leonardo; Olsson, Aaryn D.

    2015-01-01

    Resource managers are often faced with trade-offs in allocating limited resources to manage plant invasions. These decisions must often be made with uncertainty about the location of infestations, their rate of spread and effectiveness of management actions. Landscape level simulation tools such as state-and-transition simulation models (STSMs) can be used to evaluate the potential long term consequences of alternative management strategies and help identify those strategies that make efficient use of resources. We analyzed alternative management scenarios for African buffelgrass (Pennisetum ciliare syn. Cenchrus ciliaris) at Ironwood Forest National Monument, Arizona using a spatially explicit STSM implemented in the Tool for Exploratory Landscape Scenario Analyses (TELSA). Buffelgrass is an invasive grass that is spreading rapidly in the Sonoran Desert, affecting multiple habitats and jurisdictions. This invasion is creating a novel fire risk and transforming natural ecosystems. The model used in this application incorporates buffelgrass dispersal and establishment and management actions and effectiveness including inventory, treatment and post-treatment maintenance. We simulated 11 alternative scenarios developed in consultation with buffelgrass managers and other stakeholders. The scenarios vary according to the total budget allocated for management and the allocation of that budget between different kinds of management actions. Scenario results suggest that to achieve an actual reduction and stabilization of buffelgrass populations, management unconstrained by fiscal restrictions and across all jurisdictions and private lands is required; without broad and aggressive management, buffelgrass populations are expected to increase over time. However, results also suggest that large upfront investments can achieve control results that require relatively minimal spending in the future. Investing the necessary funds upfront to control the invasion results in the most

  11. Creep grazing and early weaning effects on cow and calf productivity.

    PubMed

    Harvey, R W; Burns, J C

    1988-05-01

    One hundred fifty Simmental-Hereford cows and calves were used in a 3-yr study to evaluate three creep grazing treatments and an early weaning treatment on cow and calf performance during midsummer (July to September). Calves were approximately 150 d of age and averaged 178.6 kg when treatments were initiated. Tifleaf pearl millet (Pennisetum Americanum L. Leeke) was used as the forage for two of the creep treatments, representing two cow stocking intensities of .466 (TLM1) and .239 (TLM2) ha of base hill land pasture/cow, and as pasture for early weaned calves. A red clover (Trifolium pratense L.)-Kentucky bluegrass (Poa pratensis L.) mixture was used as the other creep forage. Hill land pastures were similar for the mature cow units in all creep treatments. Calf average daily gains ranged from .93 to 1.10 kg and were not influenced (P greater than .05) by treatment. Calf gains per hectare were similar for the control, red clover and TLM1 treatments. The TLM2 and early weaning treatments resulted in increases of 105.4 and 39.1 kg of calf gain/ha (P less than .05) compared with the control. When calves were allowed to creep graze millet, decreasing the forage area from .466 to .239 ha per cow-calf unit resulted in an increase of 97.7 kg of calf gain/ha with no reduction in calf gain. Cows on the more intensively grazed millet creep treatment (TLM2) lost more weight (P less than .05) during midsummer than those on the TLM1 treatment, but they gained 18.5 kg more (P less than .10) weight than TLM1 cows between weaning and the start of winter feeding.

  12. Consequences of buffelgrass pasture development for primary productivity, perennial plant richness, and vegetation structure in the drylands of Sonora, Mexico.

    PubMed

    Franklin, Kimberly; Molina-Freaner, Francisco

    2010-12-01

    In large parts of northern Mexico native plant communities are being converted to non-native buffelgrass (Pennisetum ciliare) pastures, and this conversion could fundamentally alter primary productivity and species richness. In Sonora, Mexico land conversion is occurring at a regional scale along a rainfall-driven gradient of primary productivity, across which native plant communities transition from desert scrub to thorn scrub. We used a paired sampling design to compare a satellite-derived index of primary productivity, richness of perennial plant species, and canopy-height profiles of native plant communities with buffelgrass pastures. We sampled species richness across a gradient of primary productivity in desert scrub and thorn scrub vegetation to examine the influence of site productivity on the outcomes of land conversion. We also examined the influence of pasture age on species richness of perennial plants. Index values of primary productivity were lower in buffelgrass pastures than in native vegetation, which suggests a reduction in primary productivity. Land conversion reduced species richness by approximately 50% at local and regional scales, reduced tree and shrub cover by 78%, and reduced canopy height. Land conversion disproportionately reduced shrub species richness, which reflects the common practice among Sonoran ranchers of conserving certain tree and cactus species. Site productivity did not affect the outcomes of land conversion. The age of a buffelgrass pasture was unrelated to species richness within the pasture, which suggests that passive recovery of species richness to preconversion levels is unlikely. Our findings demonstrate that land conversion can result in large losses of plant species richness at local and regional scales and in substantial changes to primary productivity and vegetation structure, which casts doubt on the feasibility of restoring native plant communities without active intervention on the part of land managers.

  13. Enhancement of downy mildew disease resistance in pearl millet by the G_app7 bioactive compound produced by Ganoderma applanatum.

    PubMed

    Jogaiah, Sudisha; Shetty, Hunthrike Shekar; Ito, Shin-Ichi; Tran, Lam-Son Phan

    2016-08-01

    Pearl millet (Pennisetum glaucum) stands sixth among the most important cereal crops grown in the semi-arid and arid regions of the world. The downy mildew disease caused by Sclerospora graminicola, an oomycete pathogen, has been recognized as a major biotic constraint in pearl millet production. On the other hand, basidiomycetes are known to produce a large number of antimicrobial metabolites, providing a good source of anti-oomycete agrochemicals. Here, we report the discovery and efficacy of a compound, named G_app7, purified from Ganoderma applanatum on inhibition of growth and development of S. graminicola, as well as the effects of seed treatment with G_app7 on protection of pearl millet from downy mildew. G_app7 consistently demonstrated remarkable effects against S. graminicola by recording significant inhibition of sporangium formation (41.4%), zoospore release (77.5%) and zoospore motility (91%). Analyses of G_app7 compound using two-dimensional nuclear magnetic resonance spectroscopy and liquid chromatography-mass spectrometry revealed its close resemblance to metominostrobin, a derivative of strobilurin group of fungicides. Furthermore, the G_app7 was shown to stably maintain the inhibitory effects at different temperatures between 25 and 80 °C. In addition, the anti-oomycete activity of G_app7 was fairly stable for a period of at least 12 months at 4 °C and was only completely lost after being autoclaved. Seed treatment with G_app7 resulted in a significant increase in disease protection (63%) under greenhouse conditions compared with water control. The identification and isolation of this novel and functional anti-oomycete compound from G. applanatum provide a considerable agrochemical importance for plant protection against downy mildew in an environmentally safe and economical manner. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  14. Grazing Soybean to Increase Voluntary Cow Traffic in a Pasture-based Automatic Milking System

    PubMed Central

    Clark, C. E. F.; Horadagoda, A.; Kerrisk, K. L.; Scott, V.; Islam, M. R.; Kaur, R.; Garcia, S. C.

    2014-01-01

    Pasture-based automatic milking systems (AMS) require cow traffic to enable cows to be milked. The interval between milkings can be manipulated by strategically allocating pasture. The current experiment investigated the effect of replacing an allocation of grazed pasture with grazed soybean (Glycine max) with the hypothesis that incorporating soybean would increase voluntary cow traffic and milk production. One hundred and eighty mixed age, primiparous and multiparous Holstein-Friesian/Illawarra cows were randomly assigned to two treatment groups (n = 90/group) with a 2×2 Latin square design. Each group was either offered treatments of kikuyu grass (Pennisetum clandestinum Hoach ex Chiov.) pasture (pasture) or soybean from 0900 h to 1500 h during the experimental period which consisted of 2 periods of 3 days following 5 days of training and adaptation in each period with groups crossing over treatments after the first period. The number of cows trafficking to each treatment was similar together with milk yield (mean ≈18 L/cow/d) in this experiment. For the cows that arrived at soybean or pasture there were significant differences in their behaviour and consequently the number of cows exiting each treatment paddock. There was greater cow traffic (more cows and sooner) exiting pasture allocations. Cows that arrived at soybean stayed on the allocation for 25% more time and ate more forage (8.5 kg/cow/d/allocation) relative to pasture (4.7 kg/cow/d/allocation). Pasture cows predominantly replaced eating time with rumination. These findings suggest that replacing pasture with alternative grazeable forages provides no additional incentive to increase voluntary cow traffic to an allocation of feed in AMS. This work highlights the opportunity to increase forage intakes in AMS through the incorporation of alternative forages. PMID:25049970

  15. Improvement of resistance to rust through recurrent selection in pearl millet

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tapsoba, H.; Wilson, J.P.; Hanna, W.W.

    Two pearl millet [Pennisetum glaucum (L.) R.Br. = P. typhoides (Burm.) Staff & Hubb., P. americanum (L.) K. Schum.] bulk populations, Tift No. 2 and Tift No. 5, served as base populations for four cycles of recurrent selection against susceptibility to Puccinia substriata Ell. & Barth, var. indica Ramachar & Cumm. A bulk inoculum of the pathogen was used. The objectives were to evaluate the progress achieved regarding overall resistance to the pathogen in the field and resistance to different races of the pathogen, and also to evaluate changes in unselected traits. During selection, the frequency of rust resistant plantsmore » continuously increased from about 30% in each base population to more than 85% by the third cycle of selection in both populations. An average increase of about 21 and 18% per cycle was obtained in Tift No. 2 and Tift No. 5, respectively. A continuous increase of the frequency of plants resistant to some races of the pathogen was also obtained. In Tift No. 5, 80% of the plants were resistant to eight races by the third cycle of selection. The accumulation of resistance observed in the seedlings was manifested in the field, both in 1993 and 1994, by a reduction of the final rust severity from the base population to the fourth selection cycle of both populations. This improvement in resistance to the rust pathogen was accompanied by an increase in the frequency of plants resistant to Pyricularia grisea (Cooke) Sacc. only in Tift No. 2. Despite the improvement in the selected character, genetic variability for agronomic traits such as plant height, number of culms/plant, flowering date, and panicle length was successfully maintained within each population. 20 refs., 1 fig., 7 tabs.« less

  16. Structural modelling and phylogenetic analyses of PgeIF4A2 (Eukaryotic translation initiation factor) from Pennisetum glaucum reveal signature motifs with a role in stress tolerance and development

    PubMed Central

    Agarwal, Aakrati; Mudgil, Yashwanti; Pandey, Saurabh; Fartyal, Dhirendra; Reddy, Malireddy K

    2016-01-01

    Eukaryotic translation initiation factor 4A (eIF4A) is an indispensable component of the translation machinery and also play a role in developmental processes and stress alleviation in plants and animals. Different eIF4A isoforms are present in the cytosol of the cell, namely, eIF4A1, eIF4A2, and eIF4A3 and their expression is tightly regulated in cap-dependent translation. We revealed the structural model of PgeIF4A2 protein using the crystal structure of Homo sapiens eIF4A3 (PDB ID: 2J0S) as template by Modeller 9.12. The resultant PgeIF4A2 model structure was refined by PROCHECK, ProSA, Verify3D and RMSD that showed the model structure is reliable with 77 % amino acid sequence identity with template. Investigation revealed two conserved signatures for ATP-dependent RNA Helicase DEAD-box conserved site (VLDEADEML) and RNA helicase DEAD-box type, Q-motif in sheet-turn-helix and α-helical region respectively. All these conserved motifs are responsible for response during developmental stages and stress tolerance in plants. PMID:28358146

  17. Structural modelling and phylogenetic analyses of PgeIF4A2 (Eukaryotic translation initiation factor) from Pennisetum glaucum reveal signature motifs with a role in stress tolerance and development.

    PubMed

    Agarwal, Aakrati; Mudgil, Yashwanti; Pandey, Saurabh; Fartyal, Dhirendra; Reddy, Malireddy K

    2016-01-01

    Eukaryotic translation initiation factor 4A (eIF4A) is an indispensable component of the translation machinery and also play a role in developmental processes and stress alleviation in plants and animals. Different eIF4A isoforms are present in the cytosol of the cell, namely, eIF4A1, eIF4A2, and eIF4A3 and their expression is tightly regulated in cap-dependent translation. We revealed the structural model of PgeIF4A2 protein using the crystal structure of Homo sapiens eIF4A3 (PDB ID: 2J0S) as template by Modeller 9.12. The resultant PgeIF4A2 model structure was refined by PROCHECK, ProSA, Verify3D and RMSD that showed the model structure is reliable with 77 % amino acid sequence identity with template. Investigation revealed two conserved signatures for ATP-dependent RNA Helicase DEAD-box conserved site (VLDEADEML) and RNA helicase DEAD-box type, Q-motif in sheet-turn-helix and α-helical region respectively. All these conserved motifs are responsible for response during developmental stages and stress tolerance in plants.

  18. Biochemical and structural characterizations of two Dictyostelium cellobiohydrolases from the amoebozoa kingdom reveal a high level of conservation between distant phylogenetic trees of life

    DOE PAGES

    Hobdey, Sarah E.; Knott, Brandon C.; Momeni, Majid Haddad; ...

    2016-04-01

    Glycoside hydrolase family 7 (GH7) cellobiohydrolases (CBHs) are enzymes often employed in plant cell wall degradation across eukaryotic kingdoms of life, as they provide significant hydrolytic potential in cellulose turnover. To date, many fungal GH7 CBHs have been examined, yet many questions regarding structure-activity relationships in these important natural and commercial enzymes remain. Here, we present the crystal structures and a biochemical analysis of two GH7 CBHs from social amoeba: Dictyostelium discoideum Cel7A (DdiCel7A) and Dictyostelium purpureum Cel7A (DpuCel7A). DdiCel7A and DpuCel7A natively consist of a catalytic domain and do not exhibit a carbohydrate-binding module (CBM). The structures of DdiCel7Amore » and DpuCel7A, resolved to 2.1 Å and 2.7 Å, respectively, are homologous to those of other GH7 CBHs with an enclosed active-site tunnel. Two primary differences between the Dictyostelium CBHs and the archetypal model GH7 CBH, Trichoderma reesei Cel7A (TreCel7A), occur near the hydrolytic active site and the product-binding sites. To compare the activities of these enzymes with the activity of TreCel7A, the family 1 TreCel7A CBM and linker were added to the C terminus of each of the Dictyostelium enzymes, creating DdiCel7A CBM and DpuCel7A CBM, which were recombinantly expressed in T. reesei. DdiCel7A CBM and DpuCel7A CBM hydrolyzed Avicel, pretreated corn stover, and phosphoric acid-swollen cellulose as efficiently as TreCel7A when hydrolysis was compared at their temperature optima. The K i of cellobiose was significantly higher for DdiCel7A CBM and DpuCel7A CBM than for TreCel7A: 205, 130, and 29 μM, respectively. Finally, taken together, the present study highlights the remarkable degree of conservation of the activity of these key natural and industrial enzymes across quite distant phylogenetic trees of life.« less

  19. Biochemical and structural characterizations of two Dictyostelium cellobiohydrolases from the amoebozoa kingdom reveal a high level of conservation between distant phylogenetic trees of life

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hobdey, Sarah E.; Knott, Brandon C.; Momeni, Majid Haddad

    Glycoside hydrolase family 7 (GH7) cellobiohydrolases (CBHs) are enzymes often employed in plant cell wall degradation across eukaryotic kingdoms of life, as they provide significant hydrolytic potential in cellulose turnover. To date, many fungal GH7 CBHs have been examined, yet many questions regarding structure-activity relationships in these important natural and commercial enzymes remain. Here, we present the crystal structures and a biochemical analysis of two GH7 CBHs from social amoeba: Dictyostelium discoideum Cel7A (DdiCel7A) and Dictyostelium purpureum Cel7A (DpuCel7A). DdiCel7A and DpuCel7A natively consist of a catalytic domain and do not exhibit a carbohydrate-binding module (CBM). The structures of DdiCel7Amore » and DpuCel7A, resolved to 2.1 Å and 2.7 Å, respectively, are homologous to those of other GH7 CBHs with an enclosed active-site tunnel. Two primary differences between the Dictyostelium CBHs and the archetypal model GH7 CBH, Trichoderma reesei Cel7A (TreCel7A), occur near the hydrolytic active site and the product-binding sites. To compare the activities of these enzymes with the activity of TreCel7A, the family 1 TreCel7A CBM and linker were added to the C terminus of each of the Dictyostelium enzymes, creating DdiCel7A CBM and DpuCel7A CBM, which were recombinantly expressed in T. reesei. DdiCel7A CBM and DpuCel7A CBM hydrolyzed Avicel, pretreated corn stover, and phosphoric acid-swollen cellulose as efficiently as TreCel7A when hydrolysis was compared at their temperature optima. The K i of cellobiose was significantly higher for DdiCel7A CBM and DpuCel7A CBM than for TreCel7A: 205, 130, and 29 μM, respectively. Finally, taken together, the present study highlights the remarkable degree of conservation of the activity of these key natural and industrial enzymes across quite distant phylogenetic trees of life.« less

  20. Effects of Introduced Grasses, Grazing and Fire on Regional Biogeochemistry in Hawaii

    NASA Astrophysics Data System (ADS)

    Elmore, A. J.; Asner, G. P.

    2003-12-01

    African grasses introduced for grazing have expanded in geographic extent in mesic tropical systems of Hawaii and other regions of the world. Grassland expansion leads to increases in fire frequency, speeding woodland and forest destruction at greater geographic scales than occurs with grazing alone. At Pu'uwa'awa'a Ranch, Hawaii, restoration of the native woodland habitat has become a critical objective following the introduction and dominance of the African grass species Pennisetum clandestinum and P. setaceum. Grazing and grass-fueled fires have destroyed over 60% of the original forest. To stabilize these communities, managers must balance the combined effects of grazing and fire. Grazing reduces the recruitment success of native tropical trees, but grazing also reduces fire risk by moderating grass fuel conditions and restricting the extent and density of the most flammable grass species. Our study focuses on two questions: (1) What grazing intensity is necessary to change the fire conditions of a region given in situ soil and precipitation conditions? (2) Have long-term grazing conditions altered soil carbon and nitrogen stocks? We used high resolution imaging spectrometer data to measure photosynthetic and non-photosynthetic vegetation cover, analysis of soil carbon and nitrogen stocks, and measurements of plant community composition along gradients in grazing intensity. P. setaceum, the more flammable alien grass, was dominant where grazing intensity was low and at lower elevations where precipitation is low. The less flammable grass, P. clandestinum, occurred in regions of high grazing intensity and higher precipitation. Grazing influenced the dominance of P. setaceum and P. clandestinum only where precipitation and soil characteristics were suitable for both grasses to occur. At suitable sites, grazing reduced fire conditions through a species sift towards P. clandestinum. Soil carbon and nitrogen stocks decreased with grazing intensity, which was

  1. Minimising losses caused by Zucchini yellow mosaic virus in vegetable cucurbit crops in tropical, sub-tropical and Mediterranean environments through cultural methods and host resistance.

    PubMed

    Coutts, B A; Kehoe, M A; Jones, R A C

    2011-08-01

    Between 2006 and 2009, 10 field experiments were done at Kununurra, Carnarvon or Medina in Western Australia (WA) which have tropical, sub-tropical and Mediterranean climates, respectively. These experiments investigated the effectiveness of cultural control measures in limiting ZYMV spread in pumpkin, and single-gene resistance in commercial cultivars of pumpkin, zucchini and cucumber. Melon aphids (Aphis gossypii) colonised field experiments at Kununurra; migrant green peach aphids (Myzus persicae) visited but did not colonise at Carnarvon and Medina. Cultural control measures that diminished ZYMV spread in pumpkin included manipulation of planting date to avoid exposing young plants to peak aphid vector populations, deploying tall non-host barriers (millet, Pennisetum glaucum) to protect against incoming aphid vectors and planting upwind of infection sources. Clustering of ZYMV-infected pumpkin plants was greater without a 25m wide non-host barrier between the infection source and the pumpkin plants than when one was present, and downwind compared with upwind of an infection source. Host resistance gene zym was effective against ZYMV isolate Knx-1 from Kununurra in five cultivars of cucumber. In zucchini, host resistance gene Zym delayed spread of infection (partial resistance) in 2 of 14 cultivars but otherwise did not diminish final ZYMV incidence. Zucchini cultivars carrying Zym often developed severe fruit symptoms (8/14), and only the two cultivars in which spread was delayed and one that was tolerant produced sufficiently high marketable yields to be recommended when ZYMV epidemics are anticipated. In three pumpkin cultivars with Zym, this gene was effective against isolate Cvn-1 from Carnarvon under low inoculum pressure, but not against isolate Knx-1 under high inoculum pressure, although symptoms were milder and marketable yields greater in them than in cultivars without Zym. These findings allowed additional cultural control recommendations to be added

  2. Rhizosphere priming effects in two contrasting soils

    NASA Astrophysics Data System (ADS)

    Lloyd, Davidson; Kirk, Guy; Ritz, Karl

    2015-04-01

    Inputs of fresh plant-derived carbon may stimulate the turnover of existing soil organic matter by so-called priming effects. Priming may occur directly, as a result of nutrient 'mining' by existing microbial communities, or indirectly via population adjustments. However the mechanisms are poorly understood. We planted C4 Kikuyu grass (Pennisetum clandestinum) in pots with two contrasting C3 soils (clayey, fertile TB and sandy, acid SH), and followed the soil CO2 efflux and its δ13C. The extent of C deposition in the rhizosphere was altered by intermittently clipping the grass in half the pots; there were also unplanted controls. At intervals, pots were destructively sampled for root and shoot biomass. Total soil CO2 efflux was measured using a gas-tight PVC chamber fitted over bare soil, and connected to an infra-red gas analyser; the δ13C of efflux was measured in air sub-samples withdrawn by syringe. The extent of priming was inferred from the δ13C of efflux and the δ13C of the plant and soil end-members. In unclipped treatments, in both soils, increased total soil respiration and rhizosphere priming effects (RPE) were apparent compared to the unplanted controls. The TB soil had greater RPE overall. The total respiration in clipped TB soil was significantly greater than in the unplanted controls, but in the clipped SH soil it was not significantly different from the controls. Clipping affected plant C partitioning with greater allocation to shoot regrowth from about 4 weeks after planting. Total plant biomass decreased in the order TB unclipped > SH unclipped >TB clipped > SH clipped. The results are consistent with priming driven by microbial activation stimulated by rhizodeposits and by nitrogen demand from the growing plants under N limited conditions. Our data suggest that photosynthesis drives RPE and soil differences may alter the rate and intensity of RPE but not the direction.

  3. Sonoran Desert ecosystem transformation by a C4 grass without the grass/fire cycle

    USGS Publications Warehouse

    Olsson, Aaryn D.; Betancourt, Julio; McClaran, Mitchel P.; Marsh, Stuart E.

    2012-01-01

    Aim Biological invasions facilitate ecosystem transformation by altering the structure and function, diversity, dominance and disturbance regimes. A classic case is the grass–fire cycle in which grass invasion increases the frequency, scale and/or intensity of wildfires and promotes the continued invasion of invasive grasses. Despite wide acceptance of the grass–fire cycle, questions linger about the relative roles that interspecific plant competition and fire play in ecosystem transformations. Location Sonoran Desert Arizona Upland of the Santa Catalina Mountains, Arizona, USA. Methods We measured species cover, density and saguaro (Carnegiea gigantea) size structure along gradients of Pennisetum ciliare invasion at 10 unburned/ungrazed P. ciliare patches. Regression models quantified differences in diversity, cover and density with respect to P. ciliare cover, and residence time and a Fisher's exact test detected demographic changes in saguaro populations. Because P. ciliare may have initially invaded locations that were both more invasible and less diverse, we ran analyses with and without the plots in which initial infestations were located. Results Richness and diversity decreased with P. ciliare cover as did cover and density of most dominant species. Richness and diversity declined with increasing time since invasion, suggesting an ongoing transformation. The proportion of old-to-young Carnegiea gigantea was significantly lower in plots with dominant P. ciliare cover. Main conclusions Rich desert scrub (15–25 species per plot) was transformed into depauperate grassland (2–5 species per plot) within 20 years following P. ciliare invasion without changes to the fire regime. While the onset of a grass–fire cycle may drive ecosystem change in the later stages and larger scales of grass invasions of arid lands, competition by P. ciliare can drive small-scale transformations earlier in the invasion. Linking competition-induced transformation rates with

  4. Resolving the polyphyletic nature of Pyricularia (Pyriculariaceae)

    PubMed Central

    Klaubauf, S.; Tharreau, D.; Fournier, E.; Groenewald, J.Z.; Crous, P.W.; de Vries, R.P.; Lebrun, M.-H.

    2014-01-01

    Species of Pyricularia (magnaporthe-like sexual morphs) are responsible for major diseases on grasses. Pyricularia oryzae (sexual morph Magnaporthe oryzae) is responsible for the major disease of rice called rice blast disease, and foliar diseases of wheat and millet, while Pyricularia grisea (sexual morph Magnaporthe grisea) is responsible for foliar diseases of Digitaria. Magnaporthe salvinii, M. poae and M. rhizophila produce asexual spores that differ from those of Pyricularia sensu stricto that has pyriform, 2-septate conidia produced on conidiophores with sympodial proliferation. Magnaporthe salvinii was recently allocated to Nakataea, while M. poae and M. rhizophila were placed in Magnaporthiopsis. To clarify the taxonomic relationships among species that are magnaporthe- or pyricularia-like in morphology, we analysed phylogenetic relationships among isolates representing a wide range of host plants by using partial DNA sequences of multiple genes such as LSU, ITS, RPB1, actin and calmodulin. Species of Pyricularia s. str. belong to a monophyletic clade that includes all P. oryzae/P. grisea isolates tested, defining the Pyriculariaceae, which is sister to the Ophioceraceae, representing two novel families. These clades are clearly distinct from species belonging to the Gaeumannomyces pro parte/Magnaporthiopsis/Nakataea generic complex that are monophyletic and define the Magnaporthaceae. A few magnaporthe- and pyricularia-like species are unrelated to Magnaporthaceae and Pyriculariaceae. Pyricularia oryzae/P. grisea isolates cluster into two related clades. Host plants such as Eleusine, Oryza, Setaria or Triticum were exclusively infected by isolates from P. oryzae, while some host plant such as Cenchrus, Echinochloa, Lolium, Pennisetum or Zingiber were infected by different Pyricularia species. This demonstrates that host range cannot be used as taxonomic criterion without extensive pathotyping. Our results also show that the typical pyriform, 2

  5. Quantitative trait loci (QTLs) for water use and crop production traits co-locate with major QTL for tolerance to water deficit in a fine-mapping population of pearl millet (Pennisetum glaucum L. R.Br.).

    PubMed

    Tharanya, Murugesan; Kholova, Jana; Sivasakthi, Kaliamoorthy; Seghal, Deepmala; Hash, Charles Tom; Raj, Basker; Srivastava, Rakesh Kumar; Baddam, Rekha; Thirunalasundari, Thiyagarajan; Yadav, Rattan; Vadez, Vincent

    2018-04-21

    Four genetic regions associated with water use traits, measured at different levels of plant organization, and with agronomic traits were identified within a previously reported region for terminal water deficit adaptation on linkage group 2. Close linkages between these traits showed the value of phenotyping both for agronomic and secondary traits to better understand plant productive processes. Water saving traits are critical for water stress adaptation of pearl millet, whereas maximizing water use is key to the absence of stress. This research aimed at demonstrating the close relationship between traits measured at different levels of plant organization, some putatively involved in water stress adaptation, and those responsible for agronomic performance. A fine-mapping population of pearl millet, segregating for a previously identified quantitative trait locus (QTL) for adaptation to terminal drought stress on LG02, was phenotyped for traits at different levels of plant organization in different experimental environments (pot culture, high-throughput phenotyping platform, lysimeters, and field). The linkages among traits across the experimental systems were analysed using principal component analysis and QTL co-localization approach. Four regions within the LG02-QTL were found and revealed substantial co-mapping of water use and agronomic traits. These regions, identified across experimental systems, provided genetic evidence of the tight linkages between traits phenotyped at a lower level of plant organization and agronomic traits assessed in the field, therefore deepening our understanding of complex traits and then benefiting both geneticists and breeders. In short: (1) under no/mild stress conditions, increasing biomass and tiller production increased water use and eventually yield; (2) under severe stress conditions, water savings at vegetative stage, from lower plant vigour and fewer tillers in that population, led to more water available during grain filling, expression of stay-green phenotypes, and higher yield.

  6. Claviceps cyperi, a new cause of severe ergotism in dairy cattle consuming maize silage and teff hay contaminated with ergotised Cyperus esculentus (nut sedge) on the Highveld of South Africa.

    PubMed

    Naudè, T W; Botha, C J; Vorster, J H; Roux, C; Van der Linde, E J; Van der Walt, S I; Rottinghaus, G E; Van Jaarsveld, L; Lawrence, A N

    2005-03-01

    resulted in mature, heavily ergotised nut sedge being cut with the silage. Claviceps cyperi sclerotia, collected on the affected fields in the following autumn contained 3600-4000 ppm ergocryptine. That the dominant alkaloid produced by this particular fungus was indeed ergocryptine, was confirmed by negative ion chemical ionization MS/MS. In one further outbreak in another Holstein herd, teff hay contaminated with ergotised nut sedge and containing 1200 ppb alkaloids, was incriminated as the cause of the condition. This is the first report of bovine ergotism not associated with the Poaceae infected with Claviceps purpureum or endophytes but with the family Cyperaceae and this particular fungal phytopathogen.

  7. Climatic and cultural changes in the west Congo Basin forests over the past 5000 years

    PubMed Central

    Oslisly, Richard; White, Lee; Bentaleb, Ilham; Favier, Charly; Fontugne, Michel; Gillet, Jean-François; Sebag, David

    2013-01-01

    Central Africa includes the world's second largest rainforest block. The ecology of the region remains poorly understood, as does its vegetation and archaeological history. However, over the past 20 years, multidisciplinary scientific programmes have enhanced knowledge of old human presence and palaeoenvironments in the forestry block of Central Africa. This first regional synthesis documents significant cultural changes over the past five millennia and describes how they are linked to climate. It is now well documented that climatic conditions in the African tropics underwent significant changes throughout this period and here we demonstrate that corresponding shifts in human demography have had a strong influence on the forests. The most influential event was the decline of the strong African monsoon in the Late Holocene, resulting in serious disturbance of the forest block around 3500 BP. During the same period, populations from the north settled in the forest zone; they mastered new technologies such as pottery and fabrication of polished stone tools, and seem to have practised agriculture. The opening up of forests from 2500 BP favoured the arrival of metallurgist populations that impacted the forest. During this long period (2500–1400 BP), a remarkable increase of archaeological sites is an indication of a demographic explosion of metallurgist populations. Paradoxically, we have found evidence of pearl millet (Pennisetum glaucum) cultivation in the forest around 2200 BP, implying a more arid context. While Early Iron Age sites (prior to 1400 BP) and recent pre-colonial sites (two to eight centuries BP) are abundant, the period between 1600 and 1000 BP is characterized by a sharp decrease in human settlements, with a population crash between 1300 and 1000 BP over a large part of Central Africa. It is only in the eleventh century that new populations of metallurgists settled into the forest block. In this paper, we analyse the spatial and temporal

  8. Duplication and diversification of the LEAFY HULL STERILE1 and Oryza sativa MADS5 SEPALLATA lineages in graminoid Poales

    PubMed Central

    2012-01-01

    Background Gene duplication and the subsequent divergence in function of the resulting paralogs via subfunctionalization and/or neofunctionalization is hypothesized to have played a major role in the evolution of plant form. The LEAFY HULL STERILE1 (LHS1) SEPALLATA (SEP) genes have been linked with the origin and diversification of the grass spikelet, but it is uncertain 1) when the duplication event that produced the LHS1 clade and its paralogous lineage Oryza sativa MADS5 (OSM5) occurred, and 2) how changes in gene structure and/or expression might have contributed to subfunctionalization and/or neofunctionalization in the two lineages. Methods Phylogenetic relationships among 84 SEP genes were estimated using Bayesian methods. RNA expression patterns were inferred using in situ hybridization. The patterns of protein sequence and RNA expression evolution were reconstructed using maximum parsimony (MP) and maximum likelihood (ML) methods, respectively. Results Phylogenetic analyses mapped the LHS1/OSM5 duplication event to the base of the grass family. MP character reconstructions estimated a change from cytosine to thymine in the first codon position of the first amino acid after the Zea mays MADS3 (ZMM3) domain converted a glutamine to a stop codon in the OSM5 ancestor following the LHS1/OSM5 duplication event. RNA expression analyses of OSM5 co-orthologs in Avena sativa, Chasmanthium latifolium, Hordeum vulgare, Pennisetum glaucum, and Sorghum bicolor followed by ML reconstructions of these data and previously published analyses estimated a complex pattern of gain and loss of LHS1 and OSM5 expression in different floral organs and different flowers within the spikelet or inflorescence. Conclusions Previous authors have reported that rice OSM5 and LHS1 proteins have different interaction partners indicating that the truncation of OSM5 following the LHS1/OSM5 duplication event has resulted in both partitioned and potentially novel gene functions. The complex

  9. Comparative sensory and proximate evaluation of spontaneously fermenting kunu-zaki made from germinated and ungerminated composite cereal grains.

    PubMed

    Oluwajoba, Solakunmi O; Akinyosoye, Felix A; Oyetayo, Olusegun V

    2013-07-01

    This study evaluated the sensory properties, proximate composition, and overall consumer acceptability of kunu-zaki using germinated and ungerminated Sorghum bicolor (sorghum), Pennisetum americanum (millet), and Digitaria exilis (acha) cereal grains. The three cereal grains were used in nongerminated and germinated composite and noncomposite proportions coded A (Acha), S (Sorghum), M (Millet), AS (Acha-Sorghum), AM (Acha-Millet), SM (Sorghum-Millet), ASG (Acha-Sorghum Germinated), AMG (Acha-Millet Germinated), and SMG (Sorghum-Millet Germinated). Proximate analysis determined the moisture content, ash, crude fiber, fat, and crude protein content of the fermented grains. The 9-point hedonic scale was used to judge the sensory parameters of taste, color, and aroma. The paired comparison test was used to judge consumer preference between kunu-zaki made from germinated grains and the ungerminated counterpart. Scores were statistically analyzed using the Kruskal-Wallis test in the SPSS analytical software package. Panelists ranked the ASG-coded drink highest in terms of taste and aroma, the AMG-coded drink highest in terms of color. SM ranked least in terms of taste; SMG ranked least in terms of aroma; and AM ranked the least in terms of color. Preference for each parameter was significantly different (P < 0.001). Panelists ranked overall preference for the drinks from the most liked to the least liked in the order ASG>AMG>A>AS>S>M>SMG>AM>SM. The overall preference for the drinks was also significantly different (P < 0.001). Panelists pairing both ungerminated drinks with the germinated drinks ranked the ungerminated drink AS as most preferred in terms of taste, color, and aroma above its germinated counterpart ASG with preference not significantly dependent on the parameters (P = 0.065 > 0.05). Ungerminated AM was also preferred above the germinated counterpart AMG in terms of taste, color, and aroma with preference not significantly dependent on parameters (P = 0

  10. Inclusion of brown midrib dwarf pearl millet silage in the diet of lactating dairy cows.

    PubMed

    Harper, M T; Melgar, A; Oh, J; Nedelkov, K; Sanchez, G; Roth, G W; Hristov, A N

    2018-06-01

    Brown midrib brachytic dwarf pearl millet (Pennisetum glaucum) forage harvested at the flag leaf visible stage and subsequently ensiled was investigated as a partial replacement of corn silage in the diet of high-producing dairy cows. Seventeen lactating Holstein cows were fed 2 diets in a crossover design experiment with 2 periods of 28 d each. Both diets had forage:concentrate ratios of 60:40. The control diet (CSD) was based on corn silage and alfalfa haylage, and in the treatment diet, 20% of the corn silage dry matter (corresponding to 10% of the dietary dry matter) was replaced with pearl millet silage (PMD). The effects of partial substitution of corn silage with pearl millet silage on dry matter intake, milk yield, milk components, fatty acid profile, apparent total-tract digestibility of nutrients, N utilization, and enteric methane emissions were analyzed. The pearl millet silage was higher in crude protein and neutral detergent fiber and lower in lignin and starch than the corn silage. Diet did not affect dry matter intake or energy-corrected milk yield, which averaged 46.7 ± 1.92 kg/d. The PMD treatment tended to increase milk fat concentration, had no effect on milk fat yield, and increased milk urea N. Concentrations and yields of milk protein and lactose were not affected by diet. Apparent total-tract digestibility of dry matter decreased from 66.5% in CSD to 64.5% in PMD. Similarly, organic matter and crude protein digestibility was decreased by PMD, whereas neutral- and acid-detergent fiber digestibility was increased. Total milk trans fatty acid concentration was decreased by PMD, with a particular decrease in trans-10 18:1. Urinary urea and fecal N excretion increased with PMD compared with CSD. Milk N efficiency decreased with PMD. Carbon dioxide emission was not different between the diets, but PMD increased enteric methane emission from 396 to 454 g/d and increased methane yield and intensity. Substituting corn silage with brown midrib dwarf

  11. Influence of riparian vegetation on channel widening and subsequent contraction on a sand-bed stream since European settlement: Widden Brook, Australia

    NASA Astrophysics Data System (ADS)

    Erskine, Wayne; Keene, Annabelle; Bush, Richard; Cheetham, Michael; Chalmers, Anita

    2012-04-01

    Widden Brook in the Hunter Valley, Australia, was first settled by Europeans in 1831 and had widened substantially by the 1870s due to frequent floods during a flood-dominated regime impacting on highly disturbed banks whose riparian trees had been either ringbarked or cleared, and whose understorey had been grazed. Catastrophic floods in 1950 (many), two in August 1952 and one in February 1955 effected the final phase of channel widening at the onset of a second flood-dominated regime more than half a century after the initial widening. Contraction has been active since 1963 by a combination of five biogeomorphic processes. Firstly, rapid channel widening, migration and cutoffs totally reworked the pre-European floodplain and were followed by active floodplain formation. Initial bar formation was replaced by sand splay and overbank deposition which constructed a new floodplain and narrower channel. Secondly, overwidened channel segments that were produced by the catastrophic 1955 flood have contracted since 1963 by the formation of up to four bank-attached, discontinuous benches below the floodplain. Each bench has a bar nucleus of pebbly coarse sand overlain by stratified fine-medium sand and mud. Colonisation by River Sheoaks (Casuarina cunninghamiana subsp. cunninghamiana) or grasses (Cynodon dactylon, Paspalum distichum, Pennisetum clandestinum) is important in converting bars to benches. Thirdly, narrower segments which developed since 1963 have contracted by small-scale accretion on both banks. These deposits are steeply dipping, interbedded sand and mud trapped by stoloniferous and rhizomatous grasses (C. dactylon, P. distichum, P. clandestinum) which also rapidly stabilise the deposits. Fourthly, rare laterally migrating, small radius bends have contracted by recent point bar formation greatly exceeding cutbank recession rates. Point bar formation is controlled by secondary currents producing inclined stratified coarse sands without the influence of

  12. Comparative sensory and proximate evaluation of spontaneously fermenting kunu-zaki made from germinated and ungerminated composite cereal grains

    PubMed Central

    Oluwajoba, Solakunmi O; Akinyosoye, Felix A; Oyetayo, Olusegun V

    2013-01-01

    This study evaluated the sensory properties, proximate composition, and overall consumer acceptability of kunu-zaki using germinated and ungerminated Sorghum bicolor (sorghum), Pennisetum americanum (millet), and Digitaria exilis (acha) cereal grains. The three cereal grains were used in nongerminated and germinated composite and noncomposite proportions coded A (Acha), S (Sorghum), M (Millet), AS (Acha–Sorghum), AM (Acha–Millet), SM (Sorghum–Millet), ASG (Acha–Sorghum Germinated), AMG (Acha–Millet Germinated), and SMG (Sorghum–Millet Germinated). Proximate analysis determined the moisture content, ash, crude fiber, fat, and crude protein content of the fermented grains. The 9-point hedonic scale was used to judge the sensory parameters of taste, color, and aroma. The paired comparison test was used to judge consumer preference between kunu-zaki made from germinated grains and the ungerminated counterpart. Scores were statistically analyzed using the Kruskal–Wallis test in the SPSS analytical software package. Panelists ranked the ASG-coded drink highest in terms of taste and aroma, the AMG-coded drink highest in terms of color. SM ranked least in terms of taste; SMG ranked least in terms of aroma; and AM ranked the least in terms of color. Preference for each parameter was significantly different (P < 0.001). Panelists ranked overall preference for the drinks from the most liked to the least liked in the order ASG>AMG>A>AS>S>M>SMG>AM>SM. The overall preference for the drinks was also significantly different (P < 0.001). Panelists pairing both ungerminated drinks with the germinated drinks ranked the ungerminated drink AS as most preferred in terms of taste, color, and aroma above its germinated counterpart ASG with preference not significantly dependent on the parameters (P = 0.065 > 0.05). Ungerminated AM was also preferred above the germinated counterpart AMG in terms of taste, color, and aroma with preference not significantly dependent on

  13. Cumulative effects of sewage sludge and effluent mixture application on soil properties of a sandy soil under a mixture of star and kikuyu grasses in Zimbabwe

    NASA Astrophysics Data System (ADS)

    Madyiwa, S.; Chimbari, M.; Nyamangara, J.; Bangira, C.

    Although sewage effluent and sludge provides nutrients for plant growth, its continual use over extended periods can result in the accumulation of heavy metals in soils and in grass to levels that are detrimental to the food chain. This study was carried in 2001 out at Firle farm, owned by the Municipality of Harare, to assess heavy metal loading on a sandy soil and uptake of the metals by pasture grass consisting of a mixture of Cynodon nlemfuensis (star grass) and Pennisetum clandestinum Chiov (kikuyu grass) following sewage effluent and sludge application for 29 years. Firle Farm receives treated effluent and sludge emanating from domestic and industrial sources. Soil and grass samples were taken from the study area, consisting of 3 ha of non-irrigated area (control) and 1.3 ha of irrigated area. Both the soil and grass samples were tested for Cu, Zn, Ni and Pb using atomic absorption spectrophotometry. Sewage sludge addition resulted in high levels of soil pollution, especially in the 20 cm horizon, in the irrigated area when compared to the control. Grasses took up moderate levels of Cu and Zn, and limited levels of Pb. Nickel was not detectable in grasses despite high levels in the irrigated soil. Copper uptake was several times higher than the suggested potentially toxic level of 12 mg/kg [Soil Science Society of America, Micronutrients in agriculture, second ed., Wisconsin, USA, 1991]. Lead uptake averaged 1.0 mg/kg, which was below 10 mg/kg the suggested limit for agronomic crops [E.M. Seaker, Zinc, copper, cadmium and lead in minespoil, water and plants from reclaimed mine land amended with sewage sludge, 1991]. Cu and Zn showed relatively higher mobility down the soil profile than Ni and Pb. Even then, the concentrations in the lower soil layers were very small, suggesting that the metals were unlikely to contaminate groundwater. There was no direct correlation between metal levels in soils and grasses. It was postulated that it is the bio

  14. Basalt Weathering, Nutrient Uptake, And Carbon Release By An Exotic And A Native Arizona Grass Species Under Different Temperature Conditions

    NASA Astrophysics Data System (ADS)

    Gallas, G.; Dontsova, K.; Chorover, J.; Hunt, E.; Ravi, S.

    2010-12-01

    During this past summer, the National Science Foundation funded a 10-week Research Experience for Undergraduates (REU) program “Environmental and Earth Systems Research at Biosphere 2”. This program provides undergraduates with an opportunity to conduct guided research in environmental and Earth systems science and has resulted in this work. Biosphere 2 allows for the exploration of complex questions in Earth sciences because of its large scale and the precise control allowed over many experimental elements. The goal of this study was to observe plant-mediated weathering of granular basalt under two temperature conditions. Two grass species were studied, one native to Arizona: Tanglehead, Heteropogan contortus, and one exotic to Arizona: Buffelgrass, Pennisetum ciliar. The grasses were grown in pots located in the Desert and the Savannah Biomes in the Biosphere 2 to take advantage of a 4° C temperature difference. Understanding differences in how native and invasive grasses weather soil and take up nutrients may explain the mechanism behind current invasion of Sonoran Desert by exotic species and help predict response of native and invasive vegetation to expected increase in temperatures. Each biome also contained three replicate “control” pots without vegetation, and mixtures of the two grass species to observe possible competition between the species. Three factors were compared in this study: 1. Temperature: the same species of grass under two different temperature conditions 2. Species: Native Arizonan species vs. a species exotic to Arizona 3. Temporal: How the grasses use resources differently as they grow Leachate samples were collected and analyzed for pH, electrical conductivity, total organic carbon, total nitrogen, inorganic carbon by high temperature combustion coupled with infrared gas analysis; F-, Cl-, Br-, NO3-, NO2-, SO42-, and PO43- by ion chromatography; and cations and metals by ICP-MS. The data trends indicate that plants enhanced

  15. Screening for new accumulator plants in Andes Range mines

    NASA Astrophysics Data System (ADS)

    Bech, Jaume; Roca, Núria

    2016-04-01

    Toxic metal pollution of waters and soils is a major environmental problem, and most conventional remediation approaches do not provide acceptable solutions. The use of plants or plant products to restore or stabilize contaminated sites, collectively known as phytoremediation, takes advantage of the natural abilities of plants to take up, accumulate, store, or degrade organic and inorganic substances. Although not a new concept, phytoremediation is currently being re-examined as an environmentally friendly, cost-effective means of reducing metal contaminated soil. Plants growing on naturally metal-enriched soils are of particular interest in this regard, since they are genetically tolerant to high metal concentrations and have an excellent adaptation to this multi-stress environment. Processes include using plants that tolerate and accumulate metals at high levels (phytoextraction) and using plants that can grow under conditions that are toxic to other plants while preventing, for example, soil erosion (phytostabilization). Soil and plant samples were taken at polymetallic mines in Peru, Ecuador and Chile. It is suggested that Plantago orbignyana Steinheil is a Pb hyperaccumulator. Moreover, unusually elevated concentrations of Pb (over 1000 mg kg-1) and Translocation Factor (TF) greater than one were also detected in shoots of 6 different plants species (Ageratina sp., Achirodine alata, Cortaderia apalothica, Epilobium denticulatum, Taraxacum officinalis and Trifolium repens) of a Caroline mine in Perú. Among the grass species (Poaceae), the highest shoot As concentration were found in Paspalum sp. (>1000 μg g-1) and Eriochola ramose (460 μg g-1) from the Cu mine in Peru and in Holcus lanatus and Pennisetum clandestinum (>200 μg g-1) from the silver mine in Ecuador. The shoot accumulation of Zn was highest in Baccharis amdatensis (>1900 μg g-1) and in Rumex crispus (1300 μg g-1) from the Ag mine in Ecuador (Bech et al., 2002). Paspalum racemosum also

  16. Survey of invasive ants at Hakalau Forest National Wildlife Refuge

    USGS Publications Warehouse

    Peck, Robert W.; Banko, Paul C.

    2011-01-01

    We conducted a survey for invasive ants at Hakalau Forest National Wildlife Refuge, Hawai‘i Island, during 2009–2010 to evaluate potential threats to native arthropod communities and food webs. The focal area of the survey was the upper portion of the Hakalau Unit of the refuge, where native forest was being restored in abandoned cattle pastures. This area, between 1575 and 1940 m elevations, contained much alien kikuyu grass (Pennisetum clandestinum), but koa (Acacia koa) trees and other native species that were planted in the past 20 years were rapidly filling in the pasture. We surveyed for ants at predetermined points along roads, fences, and corridors of planted koa. Sampling methods primarily consisted of hand searching and pitfall traps, but bait cards were used additionally in some instances. Our results indicated that a single species, Cardiocondyla kagutsuchi, was widespread across the upper portion of the refuge. Cardiocondyla kagutsuchi seemed absent, or at least rare, in areas of tall, dense grass. Due to the undulating topography of the area, however, the dense grass cover was interspersed with outcroppings of exposed, gravelly soil. Presumably due to warming by the sun, many of the outcropped habitats supported colonies of C. kagutsuchi. We did not detect ants in the old-growth forest below the abandoned pastures, presumably because microhabitat conditions under the forest canopy were unsuitable. Although ecological impacts of C. kagutsuchi have not been reported, they may be limited by the small size of the ant, the relatively small size of colonies, and the apparent preference of the ant for disturbed areas that are dominated by alien species. Notably, our survey of Keanakolu-Mana Road between the Observatory Road (John A. Burns Way) and the town of Waimea detected a population of Argentine ants (Linepithema humile) approximately 5.1 km north of the Maulua Section of the refuge. We also surveyed for ants on the Kona Forest Unit of the refuge

  17. Uncertainty in vegetation products derived from field spectral measurements: an error budget approach

    NASA Astrophysics Data System (ADS)

    Anderson, K.; Dungan, J. L.

    2008-12-01

    One of the biggest challenges in the use of proximal remote sensing methods continues to be the accurate, reproducible characterisation of natural surface reflectance properties measured in the solar radiation environment. Complexities in such measurements arise from differences in instrument type, field-of-view, atmospheric conditions, solar illumination and measurement angles and uncertainty in the calibration of reference sources used. Three GER 1500 spectroradiometers were used to measure the reflectance of a short sward grass canopy. A full laboratory assessment was first carried out to characterise instrument uncertainty. Wavelength-dependent patterns in noise equivalent delta radiances (NEdL) were similar for all three instruments, (less than 1 W m-2 sr μm-1 in the range 400-1000 nm). The spectroradiometers were then used in the field, each in a single-beam configuration and two in a dual-field- of-view configuration to compare their field reproducibility to laboratory measurements. Hemispherical-conical reflectance factors (HCRF) were collected in clear sky conditions of a grass (Pennisetum clandestinum) canopy. Two measurement dates were used where skies were clean (diffuse-to-global (DG) irradiance ratios < 0.13) and stable (standard deviation in DG < 0.001). Spectra were collected at nadir during the two- hour period spanning solar noon with a 2° range in solar zenith angles. A reproducible method was used which enabled positioning of instruments to within 1° precision in the azimuthal direction and with no movement in zenithal position. Ten measurements were taken with each sensor head, from a calibrated optical grade Spectralon panel (99% reflecting), the grass target, and a control surface -- a grey, 75% Spectralon panel. After each sequence the sensor heads were changed. On each date, the sequence of measurements was repeated. Field results showed standard uncertainties (u) of less than 0.01 (SD in HCRF) for the grey panel and less than 0.015 for

  18. The effect of temperate or tropical pasture grazing state and grain-based concentrate allocation on dairy cattle production and behavior.

    PubMed

    Clark, C E F; Kaur, R; Millapan, L O; Golder, H M; Thomson, P C; Horadagoda, A; Islam, M R; Kerrisk, K L; Garcia, S C

    2018-06-01

    Grain-based concentrate (GBC) supplement is of high cost to dairy farmers as a feed source as opposed to grazed pasture. Milk production response to GBC is affected by the composition and nutritive value of the remainder of the diet, animal factors, and interactions between forage type and level of GBC. In grazing systems, dairy cattle encounter contrasting pasture states, primarily because the social structure of the herd affects the timing of when each animal accesses a paddock after milking as a result of a relatively consistent cow milking order. However, the effect of feed management, namely pasture state and GBC allocation, on dairy cattle production and behavior is unknown. We examined the effect of varying GBC allocation for dairy cattle grazing differing states of kikuyu grass (Pennisetum clandestinum, a tropical pasture species; experiment 1) and annual ryegrass (Lolium multiflorum L., a temperate pasture species; experiment 2) on dry matter intake, milk production and composition, and grazing behavior. For each experiment, 90 lactating dairy cattle were randomly allocated to 2 consistent (fresh-fresh and depleted-depleted) and 2 inconsistent (fresh-depleted and depleted-fresh pasture state treatments (defined as sequences of pasture state allocation for the morning and afternoon grazing events) and 3 GBC treatments [2.7, 5.4, and 8.1 kg of dry matter (DM)/cow per day], giving 12 treatment combinations for each experiment. The duration of each experiment was 14 d, with the first 7 d used as adaptation to treatment. In each experiment, 3 cattle were selected from each of the 12 pasture type × GBC treatment groups within the experimental herd to determine herbage intake and total DM digestibility using the n-alkanes method (n = 36). There was no interaction between kikuyu grass or ryegrass pasture state and GBC level for intake, digestibility, or milk yield or components. Dairy cattle offered fresh-fresh and depleted-fresh ryegrass produced 9% more milk