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Sample records for greenhouse vegetables grown

  1. Arsenic uptake and speciation in vegetables grown under greenhouse conditions.

    PubMed

    Smith, E; Juhasz, A L; Weber, J

    2009-04-01

    The accumulation of arsenic (As) by vegetables is a potential human exposure pathway. The speciation of As in vegetables is an important consideration due to the varying toxicity of different As species. In this study, common Australian garden vegetables were hydroponically grown with As-contaminated irrigation water to determine the uptake and species of As present in vegetable tissue. The highest concentrations of total As were observed in the roots of all vegetables and declined in the aerial portions of the plants. Total As accumulation in the edible portions of the vegetables decreased in the order radish > mung bean > lettuce = chard. Arsenic was present in the roots of radish, chard, and lettuce as arsenate (As(V)) and comprised between 77 and 92% of the total As present, whereas in mung beans, arsenite (As(III)) comprised 90% of the total As present. In aerial portions of the vegetables, As was distributed equally between both As(V) and As(III) in radish and chard but was present mainly as As(V) in lettuce. The presence of elevated As in vegetable roots suggests that As species may be complexed by phytochelatins, which limits As translocation to aerial portions of the plant.

  2. Evaluation of endosulfan residues in vegetables grown in greenhouses.

    PubMed

    Arrebola, F J; Egea-González, F J; Moreno, M; Fernández-Gutiérrez, A; Hernández-Torres, M E; Martínez-Vidal, J L

    2001-07-01

    The reduction in residue levels of endosulfan with time after treatment of tomatoes, green beans, peppers and cucumbers grown in different types of commercial greenhouses (flat- and asymmetric-roof greenhouses) in Almería (Spain) was investigated. A study of the major and minor degradation products of endosulfan in peppers and cucumbers (endosulfan-sulfate, -ether and -lactone) was carried out using gas chromatography-tandem mass spectrometry (GC-MS/MS). To establish the influence of environmental conditions on the degradation of endosulfan, several field trials have been carried out in which crops were sprayed at different rates (full, half- and quarter- of those rates recommended) during two seasons (spring and winter). For statistical purposes, the disappearance of endosulfan with time was considered to follow a pseudo-first-order reaction. Analysis of variance (ANOVA) has been applied to the results obtained. Half-lives of residue disappearance were 4.03-4.68 days in green beans, 4.03-4.20 days in tomatoes, 8.22 days in peppers and 7.97 days in cucumbers. Half-lives in spring were shorter than in the winter season. The application rate and the type of greenhouse did not influence the half-lives.

  3. The first "space" vegetables have been grown in the "SVET" greenhouse using controlled environmental conditions

    NASA Astrophysics Data System (ADS)

    Ivanova, T. N.; Bercovich, Yu. A.; Mashinskiy, A. L.; Meleshko, G. I.

    The paper describes the "SVET" project—a new generation of space greenhouse with small dimensions. Through the use of a minicomputer, "SVET" is fully capable of automatically operating and controlling environmental systems for higher plant growth. A number of preliminary studies have shown the radish and cabbage to be potentially important crops for CELSS (Closed Environmental Life Support System). The "SVET" space greenhouse was mounted on the "CRYSTAL" technological module docked to the Mir orbital space station on 10 June 1990. Soviet cosmonauts Balandin and Solovyov started the first experiments with the greenhouse on 15 June 1990. Preliminary results of seed cultivation over an initial 54-day period in "SVET" are presented. Morphometrical characteristics of plants brought back to Earth are given. Alteration in plant characteristics, such as growth and developmental changes, or morphological contents were noted. A crop of radish plants was harvested under microgravity conditions. Characteristics of plant environmental control parameters and an estimation of functional properties of control and regulation systems of the "SVET" greenhouse in space flight as received via telemetry data is reported.

  4. A greenhouse and field-based study to determine the accumulation of arsenic in common homegrown vegetables grown in mining-affected soils

    PubMed Central

    Ramirez-Andreotta, Monica D.; Brusseau, Mark L.; Artiola, Janick F.; Maier, Raina M.

    2012-01-01

    The uptake of arsenic by plants from contaminated soils presents a health hazard that may affect home gardeners neighboring contaminated environments. A controlled greenhouse study was conducted in parallel with a co-created citizen science program (home garden experiment) to characterize the uptake of arsenic by common homegrown vegetables near the Iron King Mine and Humboldt Smelter Superfund site in southern Arizona. The greenhouse and home garden arsenic soil concentrations varied considerably, ranging from 2.35 to 533 mg kg−1. In the greenhouse experiment four vegetables were grown in three different soil treatments and in the home garden experiment a total of 63 home garden produce samples were obtained from 19 properties neighboring the site. All vegetables accumulated arsenic in both the greenhouse and home garden experiments, ranging from 0.01 to 23.0 mg kg−1 dry weight. Bioconcentration factors were determined and show that arsenic uptake decreased in the order: Asteraceae > Brassicaceae > Amaranthaceae > Cucurbitaceae > Liliaceae > Solanaceae > Fabaceae. Certain members of the Asteraceae and Brassicaceae plant families have been previously identified as hyperaccumulator plants, and it can be inferred that members of these families have genetic and physiological capacity to accumulate, translocate, and resist high amounts of metals. Additionally, a significant linear correlation was observed between the amount of arsenic that accumulated in the edible portion of the plant and the arsenic soil concentration for the Asteraceae, Brassicaceae, Amaranthaceae, and Fabaceae families. The results suggest that home gardeners neighboring mining operations or mine tailings with elevated arsenic levels should be made aware that arsenic can accumulate considerably in certain vegetables, and in particular, it is recommended that gardeners limit consumption of vegetables from the Asteraceae and Brassicaceae plant families. PMID:23201696

  5. A greenhouse and field-based study to determine the accumulation of arsenic in common homegrown vegetables grown in mining-affected soils.

    PubMed

    Ramirez-Andreotta, Monica D; Brusseau, Mark L; Artiola, Janick F; Maier, Raina M

    2013-01-15

    The uptake of arsenic by plants from contaminated soils presents a health hazard that may affect home gardeners neighboring contaminated environments. A controlled greenhouse study was conducted in parallel with a co-created citizen science program (home garden experiment) to characterize the uptake of arsenic by common homegrown vegetables near the Iron King Mine and Humboldt Smelter Superfund site in southern Arizona. The greenhouse and home garden arsenic soil concentrations varied considerably, ranging from 2.35 to 533 mg kg(-1). In the greenhouse experiment four vegetables were grown in three different soil treatments and in the home garden experiment a total of 63 home garden produce samples were obtained from 19 properties neighboring the site. All vegetables accumulated arsenic in both the greenhouse and home garden experiments, ranging from 0.01 to 23.0 mg kg(-1) dry weight. Bioconcentration factors were determined and show that arsenic uptake decreased in the order: Asteraceae>Brassicaceae>Amaranthaceae>Cucurbitaceae>Liliaceae>Solanaceae>Fabaceae. Certain members of the Asteraceae and Brassicaceae plant families have been previously identified as hyperaccumulator plants, and it can be inferred that members of these families have genetic and physiological capacity to accumulate, translocate, and resist high amounts of metals. Additionally, a significant linear correlation was observed between the amount of arsenic that accumulated in the edible portion of the plant and the arsenic soil concentration for the Asteraceae, Brassicaceae, Amaranthaceae, and Fabaceae families. The results suggest that home gardeners neighboring mining operations or mine tailings with elevated arsenic levels should be made aware that arsenic can accumulate considerably in certain vegetables, and in particular, it is recommended that gardeners limit consumption of vegetables from the Asteraceae and Brassicaceae plant families. Copyright © 2012 Elsevier B.V. All rights reserved.

  6. From fresh vegetables to the harvest of wheat plants grown in the "SVET" space greenhouse onboard the MIR orbital station.

    PubMed

    Ivanova, T; Kostov, P; Sapunova, S; Dandolov, I; Sytchev, V; Podolski, I; Levinskikh, M; Meleshko, G; Bingham, G; Salisbury, F

    1997-07-01

    Researchers report the results of experiments conducted onboard MIR in 1990, 1995, and 1996 in raising edible crops. In the 1990 experiment, radishes and Chinese cabbage were grown successfully, though the experimental plants were up to four times smaller than controls at harvest. The 1995 experiment in growing wheat through a complete life cycle was not completed. The 1996 experiment was successful in growing wheat through a complete life cycle to the seed stage. No seeds developed on any of the 279 ears harvested in that experiment. Reasons for the seedless development are explored.

  7. From fresh vegetables to the harvest of wheat plants grown in the "SVET" space greenhouse onboard the MIR orbital station

    NASA Technical Reports Server (NTRS)

    Ivanova, T.; Kostov, P.; Sapunova, S.; Dandolov, I.; Sytchev, V.; Podolski, I.; Levinskikh, M.; Meleshko, G.; Bingham, G.; Salisbury, F.

    1997-01-01

    Researchers report the results of experiments conducted onboard MIR in 1990, 1995, and 1996 in raising edible crops. In the 1990 experiment, radishes and Chinese cabbage were grown successfully, though the experimental plants were up to four times smaller than controls at harvest. The 1995 experiment in growing wheat through a complete life cycle was not completed. The 1996 experiment was successful in growing wheat through a complete life cycle to the seed stage. No seeds developed on any of the 279 ears harvested in that experiment. Reasons for the seedless development are explored.

  8. From fresh vegetables to the harvest of wheat plants grown in the "SVET" space greenhouse onboard the MIR orbital station

    NASA Technical Reports Server (NTRS)

    Ivanova, T.; Kostov, P.; Sapunova, S.; Dandolov, I.; Sytchev, V.; Podolski, I.; Levinskikh, M.; Meleshko, G.; Bingham, G.; Salisbury, F.

    1997-01-01

    Researchers report the results of experiments conducted onboard MIR in 1990, 1995, and 1996 in raising edible crops. In the 1990 experiment, radishes and Chinese cabbage were grown successfully, though the experimental plants were up to four times smaller than controls at harvest. The 1995 experiment in growing wheat through a complete life cycle was not completed. The 1996 experiment was successful in growing wheat through a complete life cycle to the seed stage. No seeds developed on any of the 279 ears harvested in that experiment. Reasons for the seedless development are explored.

  9. Transgene expression of lilies grown in the greenhouse and outdoors

    USDA-ARS?s Scientific Manuscript database

    Lilium longiflorum cv. Nellie White plants were transformed with either the bar-uidA fusion gene or the npt II and uidA genes and grown for two seasons in the greenhouse and outdoors in containers. All transgenes were under control of the CaMV 35S promoter. During the first year there was no differ...

  10. Accumulation status, sources and phytoavailability of metals in greenhouse vegetable production systems in Beijing, China.

    PubMed

    Xu, Li; Lu, Anxiang; Wang, Jihua; Ma, Zhihong; Pan, Ligang; Feng, Xiaoyuan; Luan, Yunxia

    2015-12-01

    The accumulation status, sources and phytoavailability of selected metals in greenhouse vegetable production systems in peri-urban areas of Beijing were investigated. The mean concentrations of As, Cd, Cr, Hg and Pb in greenhouse soils were 8.44, 0.25, 69.0, 0.09 and 22.0 mg kg(-1), dw, respectively. According to principal component analysis, As, Cd, Cr and Hg are mainly from anthropogenic source, but Pb is likely from natural source. Metal concentrations in all vegetable samples were decreased in the order of Cr>As>Pb>Cd>Hg. Compared with root and fruit vegetables, leaf vegetables had relatively high concentrations and transfer factors of heavy metals, except for Cd. By including soil pH, OM and greenhouse soil metals, 10 empirical models were derived using stepwise multiple linear regression analysis to predict heavy metal concentrations in the edible parts of different vegetables. Among the different vegetable groups, the highest intakes of metals occurred through consumption of leaf vegetables for the two age groups, except for Cd. The HI value of the studied metals were all below 1, indicating that consumption of vegetables grown in greenhouse soils was of low risk to consumers in our study area. Copyright © 2015 Elsevier Inc. All rights reserved.

  11. [Effects of solar greenhouse vegetable cultivation on soil physical quality].

    PubMed

    Sun, Yan; Wang, Yi-quan; Liu, Jun; Xia, Fa-sheng; Wang, Jin-gui; Li, Jian-bo

    2011-08-01

    Taking the solar greenhouse heavy loam soil having been planted vegetables for different years at Yunyang Town in Jingyang County of Shaanxi Province as test objects, and with the uncovered vegetable soil adjacent to the greenhouse as the control, this paper studied the effects of solar greenhouse vegetable cultivation on soil physical quality. Solar greenhouse vegetable cultivation had greater effects on the bulk density of 0-30 cm soil layer (an increase in 0-10 cm soil layer and a decrease in 10-30 cm soil layer), but little effects on that of 30-40 cm soil layer. In 0-40 cm solar greenhouse soil profile, the contents of < 0.01 mm physical clay and < 0.001 mm clay were lower in upper layer than in deeper layer, indicating their downward movement, and this phenomenon was more obvious with increasing year of solar greenhouse vegetable cultivation. Within the first 5 years of solar greenhouse vegetable cultivation, soil field water capacity decreased significantly, with a decrement of 13.8%, but remained relatively stable after then.

  12. Comparison of hydrocarbon yields in cotton from field grown vs. greenhouse grown plants

    USDA-ARS?s Scientific Manuscript database

    Four accession of cotton (SA-1181, 1403, 1419, and 2269) were grown both in field conditions and a greenhouse to compare the environmental effects on leaf biomass, % yield of hydrocarbons (HC), and total HC (g HC /g leaves) under natural and controlled (protected) conditions. Leaf biomass was simi...

  13. Dieldrin uptake by vegetable crops grown in contaminated soils.

    PubMed

    Donnarumma, Lucia; Pompi, Valter; Faraci, Alessandro; Conte, Elisa

    2009-06-01

    The aim of these trials was to study the distribution of dieldrin in soil and its translocation to roots and the aerial parts of vegetable crops grown in greenhouses and fields. The main objectives were to characterize dieldrin accumulation in plant tissues in relation to the levels of soil contamination; uptake capability among plants belonging to different species, varieties and cultivars. The presence of the contaminant was quantified by gas chromatography-electron capture detector (GC-ECD) and confirmed by gas chromatography-mass spectrometer (GC-MS). The results showed a translocation of residues in cucurbitaceous fruits and flowers confirming that zucchini, cucumber and melon are crops with high uptake capability. The maximum level of dieldrin residue at 0.01 mg/kg was found to be a threshold value to safeguard the quality production of cucurbits. Tomato, lettuce and celery were identified as substitute crops to grow in contaminated fields.

  14. Phytochemical phenolics in organically grown vegetables.

    PubMed

    Young, Janice E; Zhao, Xin; Carey, Edward E; Welti, Ruth; Yang, Shie-Shien; Wang, Weiqun

    2005-12-01

    Fruit and vegetable intake is inversely correlated with risks for several chronic diseases in humans. Phytochemicals, and in particular, phenolic compounds, present in plant foods may be partly responsible for these health benefits through a variety of mechanisms. Since environmental factors play a role in a plant's production of secondary metabolites, it was hypothesized that an organic agricultural production system would increase phenolic levels. Cultivars of leaf lettuce, collards, and pac choi were grown either on organically certified plots or on adjacent conventional plots. Nine prominent phenolic agents were quantified by HPLC, including phenolic acids (e. g. caffeic acid and gallic acid) and aglycone or glycoside flavonoids (e. g. apigenin, kaempferol, luteolin, and quercetin). Statistically, we did not find significant higher levels of phenolic agents in lettuce and collard samples grown organically. The total phenolic content of organic pac choi samples as measured by the Folin-Ciocalteu assay, however, was significantly higher than conventional samples (p < 0.01), and seemed to be associated with a greater attack the plants in organic plots by flea beetles. These results indicated that although organic production method alone did not enhance biosynthesis of phytochemicals in lettuce and collards, the organic system provided an increased opportunity for insect attack, resulting in a higher level of total phenolic agents in pac choi.

  15. Heavy metals in intensive greenhouse vegetable production systems along Yellow Sea of China: Levels, transfer and health risk.

    PubMed

    Hu, Wenyou; Huang, Biao; Tian, Kang; Holm, Peter E; Zhang, Yanxia

    2017-01-01

    Recently, greenhouse vegetable production (GVP) has grown rapidly and counts a large proportion of vegetable production in China. In this study, the accumulation, health risk and threshold values of selected heavy metals were evaluated systematically. A total of 120 paired soil and vegetable samples were collected from three typical intensive GVP systems along the Yellow Sea of China. Mean concentrations of Cd, As, Hg, Pb, Cu and Zn in greenhouse soils were 0.21, 7.12, 0.05, 19.81, 24.95 and 94.11 mg kg(-1), respectively. Compared to rootstalk and fruit vegetables, leafy vegetables had relatively high concentrations and transfer factors of heavy metals. The accumulation of heavy metals in soils was affected by soil pH and soil organic matter. The calculated hazard quotients (HQ) of the heavy metals by vegetable consumption decreased in the order of leafy > rootstalk > fruit vegetables with hazard index (HI) values of 0.61, 0.33 and 0.26, respectively. The HI values were all below 1, which indicates that there is a low risk of greenhouse vegetable consumption. Soil threshold values (STVs) of heavy metals in GVP system were established according to the health risk assessment. The relatively lower transfer factors of rootstalk and fruit vegetables and higher STVs suggest that these types of vegetables are more suitable for cultivation in greenhouse soils. This study will provide an useful reference for controlling heavy metals and developing sustainable GVP.

  16. Agriculture: Nurseries and Greenhouses

    EPA Pesticide Factsheets

    Nurseries and Greenhouses. Information about environmental requirements specifically relating to the production of many types of agricultural crops grown in nurseries and greenhouses, such as ornamental plants and specialty fruits and vegetables.

  17. An assessment of greenhouse gas emissions from the Australian vegetables industry.

    PubMed

    Maraseni, Tek N; Cockfield, Geoff; Maroulis, Jerry; Chen, Guangnan

    2010-08-01

    Recently, partly due to the increasing carbon consciousness in the electorates and partly due to the imminent introduction of the Australian Government's Carbon Pollution Reduction Scheme (CPRS), estimating carbon footprints is becoming increasingly necessary in agriculture. By taking data from several sources, this study estimates the national greenhouse gas (GHG) emissions from a variety of farm inputs, for the 23 key vegetables crops grown in Australia. For the 121,122 ha of land occupied by vegetable farms, there are 1.1 MtCO(2)e GHG emissions or 9.2 tCO(2)e ha(-1). In total, 65% of total GHG emissions from the vegetable industry are due to electricity use for irrigation and post-harvest on-farm activities, 17% from soil N(2)O emissions due to N fertiliser use, 10% from agrochemicals, 7% through fossils fuels and 1% from on-farm machinery. The top four vegetables (by area), potatoes, lettuce, tomatoes and broccoli account for 29.1%, 7.9%, 5.9% and 7.2% of total GHG emissions from vegetables, respectively. However, the ratio of GHG emissions between the highest and lowest-emitting crops per hectare and per tonne, are different. Therefore, care must be exercised in carbon footprint labelling vegetable products to ensure that the labels reflect carbon emissions on a per tonnage basis.

  18. Uptake of di-(2-ethylhexyl) phthalate of vegetables from plastic film greenhouses.

    PubMed

    Fu, Xiaowei; Du, Qizhen

    2011-11-09

    Uptake of di-(2-ethylhexyl) phthalate (DEHP) of nine vegetables including potherb mustard, bok choy, celery, spinach, cabbage, leaf of tube, lettuce, garlic, and edible amaranth in plastic film greenhouses with different plastic films, film thickness, greenhouse age, and greenhouse height was studied. The results showed that the higher the DEHP content of film, the thicker the film, the lower the height of the greenhouse, and the younger the age of the greenhouse were, the higher the DEHP concentration of vegetables was. The results afford significant information for production of safe vegetables with low level DEHP contamination.

  19. Arsenic and Lead Uptake by Vegetable Crops Grown on Historically Contaminated Orchard Soils

    PubMed Central

    2015-01-01

    Transfer of Pb and As into vegetables grown in orchard soils historically contaminated by Pb arsenate pesticides was measured in the greenhouse. Lettuce, carrots, green beans and tomatoes were grown on soils containing a range of total Pb (16.5–915 mg/kg) and As (6.9–211 mg/kg) concentrations. The vegetables were acid-digested and analyzed for total Pb and As using ICP-mass spectrometry. Vegetable contamination was dependent on soil total Pb and As content, pH, and vegetable species. Arsenic concentrations were highest in lettuce and green beans, lower in carrots, and much lower in tomato fruit. Transfer of Pb into lettuce and beans was generally lower than that of As, and Pb and As were strongly excluded from tomato fruit. Soil metal concentrations as high as 400 mg/kg Pb and 100 mg/kg As produced vegetables with concentrations of Pb and As below the limits of international health standards. PMID:26949393

  20. Optimum returns from greenhouse vegetables under water quality and risk constraints in the United Arab Emirates

    USDA-ARS?s Scientific Manuscript database

    Greenhouses have been used in the United Arab Emirates (UAE) to produce vegetables that contribute toward UAE food security, including offering fresh vegetable produce in the off-season. However, to manage such greenhouses farmers face both technical and environmental limitations (i.e., high water s...

  1. The impact of greenhouse vegetable farming duration and soil types on phytoavailability of heavy metals and their health risk in eastern China.

    PubMed

    Yang, Lanqin; Huang, Biao; Hu, Wenyou; Chen, Yong; Mao, Mingcui; Yao, Lipeng

    2014-05-01

    Heavy metal contamination in vegetables from greenhouse vegetable production (GVP) in China requires major attention. For GVP sustainability at a large regional level, 441 surface GVP soil and 132 corresponding greenhouse vegetable samples were collected from six typical GVP bases in eastern China to systematically evaluate the impact of GVP duration and soil types (Anthrosols and Cambosols) on phytoavailability of four major metals, Cd, Cu, Zn, and Pb, and their health risk. The results revealed high Cd accumulation in leaf vegetables grown in Anthrosols, which might pose potential health risk. Regardless of soil types in the study region, greenhouse farming lowered soil pH and enhanced metal availability with rising GVP duration, which might exacerbate Cd phytoavailability and vegetable Cd contamination as well as potential health risk. Also, increased GVP soil organic matter contents over time, found in some locations, affected crop-depending Cu and Zn uptakes. Furthermore, due to GVP, the annual decrease rate of soil pH and increase rates of soil available metal concentrations were generally much greater in Anthrosols than those in Cambosols, which contributed a lot to high Cd uptake by leaf vegetables grown in Anthrosols and their potential health risk. From sustainable GVP perspective, fertilization strategy with reduced frequency and rate is especially important and effective for abating soil and vegetable contamination by heavy metals under greenhouse farming.

  2. Effects of exogenous abscisic acid on yield, antioxidant capacities, and phytochemical contents of greenhouse grown lettuces.

    PubMed

    Li, Zheng; Zhao, Xin; Sandhu, Amandeep K; Gu, Liwei

    2010-05-26

    Antioxidants and phytochemicals in vegetables are known to provide health benefits. Strategies that enhance these properties are expected to increase the nutritional values of vegetables. The objective of this research is to assess the effects of exogenous abscisic acid (ABA) on yield, antioxidant capacities, and phytochemical content of lettuces grown in a greenhouse. Red loose leaf lettuce (cv. Galactic) and green loose leaf lettuce (cv. Simpson Elite) were cultivated using a randomized complete block design. Three concentrations of ABA in water [0 (control), 150, 300 ppm] were sprayed on the 30th and 39th days after sowing, and lettuces were harvested on the 46th day. Exogenous ABA significantly decreased yield of green and red lettuces. Total phenolic and total anthocyanin contents in red lettuce treated with ABA were significantly higher than in controls, whereas no significant differences were observed in green lettuce. ABA significantly induced the accumulation of chlorophyll b and total carotenoids in lettuces. The phenolic compounds identified and quantified in red and green lettuces included caffeoyltartaric acid, 5-O-caffeoylquinic acid, dicaffeoyltartaric acid, 3,5-dicaffeoylquinic acid, and quercetin 3-(6''-malonyl)-glucoside. Additionally, cyanidin 3-glucoside, cyanidin 3-(3''-malonoyl)-glucoside, and cyanidin 3-(6''-malonoyl)-glucoside in red lettuces were quantified. No significant effects of ABA on these individual phytochemicals were observed in green lettuces, whereas ABA significantly elevated the content of individual phytochemicals in red lettuces except for 5-O-caffeoylquinic acid. Differences among red lettuces with or without exogenous ABA were visualized on the score plots of principal component analyses. Loading plot indicated that multiple phenolic compounds contributed to the observed differences in red lettuces.

  3. Effect of localizing fruit and vegetable consumption on greenhouse gas emissions and nutrition, Santa Barbara County.

    PubMed

    Cleveland, David A; Radka, Corie N; Müller, Nora M; Watson, Tyler D; Rekstein, Nicole J; Wright, Hannah Van M; Hollingshead, Sydney E

    2011-05-15

    The US agrifood system is very productive, but highly centralized and resource intensive with very weak links between production and consumption. This contributes to high levels of malnutrition and greenhouse gas emissions (GHGE). A popular approach to improvement is localization-reducing direct transport (farm to retail distance, or "food miles"). We examined Santa Barbara County (SBC) California, which mirrors the high production, nutritional and environmental problems, and growing localization movement of California. SBC ranks in the top 1% of US counties in value of agricultural products, and >80% of this value is produce (fruits and vegetables). We calculated the amount of produce grown in and consumed in SBC and estimated that >99% of produce grown in SBC is exported from the county, and >95% of produce consumed in SBC is imported. If all produce consumed in SBC was grown in the county (100% localization), it would reduce GHGE from the agrifood system <1%, and not necessarily affect nutrition. While food miles capture only a portion of the environmental impact of agrifood systems, localization could be done in ways that promote synergies between improving nutrition and reducing GHGE, and many such efforts exist in SBC.

  4. [Analyzing the factors of influencing the musculoskeletal disorders of greenhouse vegetable farmers].

    PubMed

    Dong, Hong-yun; Li, Hong-jun; Yu, Su-fang

    2012-03-01

    To study the prevalence of musculoskeletal disorders (MSDs) among greenhouse vegetable farmers and to explore the risk factors of MSDs. A household questionnaire survey was conducted to investigate 203 greenhouse vegetable farmers and 127 non-greenhouse vegetable farmers in February, 2011. The one-year prevalence rates of MSDs were 70.0% and 33.9% among greenhouse vegetable farmers and non-greenhouse vegetable farmers, respectively. The three main positions of MSDs in greenhouse farmers were low back, knee (s) and shoulder (s). Age, working years, body weight and usage of rolling machine were statistically associated with MSDs of greenhouse farmers, ORadj values were 1.17, 1.82, 1.08 and 0.07, respectively. The prevalence of MSDs is high in greenhouse workers. Low back pain, knee (s), and shoulder (s) disorders are the main disorders. Age, working years, body weight and usage of rolling machine are main risk factors for the development of MSDs in greenhouse farmers.

  5. Determination and degradation of methomyl in tomatoes and green beans grown in greenhouses.

    PubMed

    Gil Garcia, M D; Martínez Vidal, J L; Martínez Galera, M; Rodríguez Torreblanca, C; Gonzalez, C

    1997-01-01

    A liquid chromatographic (LC) method using UV detection at 233 nm was used to study the degradation of methomyl in tomatoes and green beans grown in greenhouses. A liquid-liquid extraction with CH2Cl2-methanol (90 + 10, v/v) and a cleanup step with Florisil were combined with LC to isolate, recover, and quantitate the pesticide. Average recoveries obtained at spike levels of 0.03 and 0.40 mg/kg were 83.2-84.7% for tomatoes and 83.3-87.5% for green beans. Determination limits were 0.03 mg/kg for tomatoes and 0.01 mg/kg for green beans. Levels of methomyl residues were studied in tomatoes and green beans grown in an experimental greenhouse to establish the effect of the kind of greenhouse, application dose, species grown, and climatic conditions on the degradation of this pesticide. Analysis of variance showed that doses did not affect the response. The half-life, however, is greater in a flat-roof greenhouse than in an asymmetric-roof greenhouse and is significantly longer for green beans than for tomatoes and longer in winter than in spring. A preharvest time of about 5 days may be suitable for green beans sprayed with methomyl. Tomatoes show residue levels at the time of application lower than Spanish minimum residue levels.

  6. Consumer sensory analysis of organically and conventionally grown vegetables.

    PubMed

    Zhao, Xin; Chambers, Edgar; Matta, Ziad; Loughin, Thomas M; Carey, Edward E

    2007-03-01

    Consumers of organically grown fruits and vegetables often believe that these products taste better than conventional produce. However, comparison of produce from supermarket shelves does not permit adequate assessment of this consumer perception, given potentially confounding cultivar and environmental effects. We used replicated side-by-side plots to produce organic and conventional vegetables for consumer sensory studies. In one test, red loose leaf lettuce, spinach, arugula, and mustard greens, grown organically and conventionally, were evaluated for overall liking as well as for intensity of flavor and bitterness. Another consumer test was conducted comparing organically and conventionally grown tomatoes, cucumbers, and onions. Overall, organically and conventionally grown vegetables did not show significant differences in consumer liking or consumer-perceived sensory quality. The only exception was in tomatoes where the conventionally produced tomato was rated as having significantly stronger flavor than the organically produced tomato. However, overall liking was the same for both organic and conventional samples. As conventional tomatoes also were scored marginally significantly higher in ripeness and a positive correlation was found between ratings of flavor intensity and ripeness, the flavor difference observed could not be simply ascribed to the contrasting growing conditions. Consumer panelists in both tests considered organic produce to be healthier (72%) and more environmentally friendly (51%) than conventional produce, while 28% considered organic produce to have better taste. Covariance analysis indicated that consumer demographics affected sensory comparisons of organic and conventional lettuce and cucumbers. Future study is needed to substantiate the influence of segmentation of consumers on their preference for organic food.

  7. Metabolite changes in nine different soybean cultivars grown under field and greenhouse conditions

    USDA-ARS?s Scientific Manuscript database

    Differences in the primary (amino acids, organic acids, and sugars) and secondary (isoflavones, fatty acid methyl esters) metabolites of nine soybean varieties grown in the field and in greenhouses were investigated by chemometric tools to identify the metabolic patterns associated with the growing ...

  8. First report of Impatiens necrotic spot virus infecting greenhouse-grown potatoes in Washington State

    USDA-ARS?s Scientific Manuscript database

    In April and May 2010, potato (Solanum tuberosum L. cv. Atlantic) plants grown from pre-nuclear minitubers in three separate greenhouses located at the USDA-ARS facility in Prosser, WA exhibited necrotic spots on leaves similar to those produced by the early blight pathogen, Alternaria solani (Sor.)...

  9. Listeria monocytogenes Internalizes in Romaine Lettuce Grown in Greenhouse Conditions.

    PubMed

    Shenoy, Archana G; Oliver, Haley F; Deering, Amanda J

    2017-04-01

    Listeria monocytogenes has been implicated in a number of outbreaks involving fresh produce, including an outbreak in 2016 resulting from contaminated packaged salads. The persistence and internalization potential of L. monocytogenes in romaine lettuce was evaluated, and the persistence of two L. monocytogenes strains was assessed on three romaine lettuce cultivars. Seeds were germinated, and plants grown in three soil types (i.e., standard potting mix, autoclaved potting mix, and top soil) and sterile soft-top agar for up to 21 days. Average CFU per gram of L. monocytogenes on seeds and plants was calculated from five replicates per harvest day. Up to 8.2 log CFU/g L. monocytogenes persisted on romaine lettuce plants (Braveheart cultivar) grown in soft-top agar, while those grown in commercial potting mix (initial soil aerobic plate count of 4.0 × 10(4) CFU/g) had a final concentration of 5.4 log CFU/g, and autoclaved commercial potting mix had a final concentration of 3.8 ± 0.2 log CFU/g after a 21-day period. Pathogen levels dropped below the limit of detection (2 log CFU/g) by day 18 in 75% topsoil (initial soil aerobic plate count of 4.0 × 10(1) CFU/g); this did not occur in sterile media. Although L. monocytogenes strain differences and presence of a clay coating on seeds did not affect persistence, differences were observed in L. monocytogenes growth and survival among cultivars. To assess internalization, seeds were inoculated with L. monocytogenes expressing green fluorescent protein. Three plants were fixed, paraffin embedded, and sectioned; localization was studied by using standard immunohistochemistry techniques. A total of 539 internalized L. monocytogenes cells were visualized among three 20-day seedlings. L. monocytogenes cells were located in all major tissue types (pith followed by cortex, xylem, phloem, and epidermis). The presence of L. monocytogenes in the plant vasculature suggests potential for transport throughout the plant into edible

  10. Distribution and uptake pathways of organochlorine pesticides in greenhouse and conventional vegetables.

    PubMed

    Zhang, Anping; Luo, Wenxiu; Sun, Jianqiang; Xiao, Hang; Liu, Weiping

    2015-02-01

    The application of greenhouse vegetable cultivation has dramatically expanded worldwide during the last several decades. However, little information is available on the distribution and uptake of pesticides in greenhouse vegetables. To bridge this knowledge gap, the present study was initiated to investigate the distribution and uptake of organochlorine pesticides (OCPs) in vegetables from plastic greenhouse and conventional cultivation methods. The uptake pathways of OCPs were not significantly different between these two cultivation methods. The arithmetic means of OCP concentrations in greenhouse vegetables were higher than those in conventional vegetables, although there was no significant difference. This small difference raised the concern of whether the tiny difference could be magnified to a significant difference by bioaccumulation in the food chain. The issue should be addressed by a well-designed scheme in future studies.

  11. Feasibility of vermicomposting for vegetable greenhouse waste recycling.

    PubMed

    Fernández-Gómez, Manuel J; Romero, Esperanza; Nogales, Rogelio

    2010-12-01

    This study was conducted in order to evaluate the feasibility of Eisenia andrei for vermicomposting heterogeneous-plant (HP), tomato-plant (P), and damaged tomato-fruit (T) greenhouse vegetable wastes. Earthworm growth and reproduction were monitored over a 12-week period, and variations in chemical parameters, enzyme activity, phytotoxicity test, and genetic fingerprinting of bacterial communities were evaluated. While high rates of salinity prevented earthworm survival in HP and P (>10 dS m(-1)), T was vermicomposted recording an adequate earthworm growth and cocoon production. The latter waste was successfully stabilized, as indicated by the significant decrease in its TOC content ( approximately 13-26%) and C:N ratio ( approximately 16-36%) and its high germination indices ( approximately 39-72%). The similar enzyme activities levels and bacterial community fingerprintings recorded in diverse vermicomposts obtained from T waste indicate that this type of waste favoured the existence of analogous bacterial communities responsible for the high degree of stabilization and maturity detected. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

  12. Survival of Escherichia coli on strawberries grown under greenhouse conditions.

    PubMed

    Shaw, Angela Laury; Svoboda, Amanda; Jie, Beatrice; Nonnecke, Gail; Mendonca, Aubrey

    2015-04-01

    Strawberries are soft fruit that are not recommended to have a post-harvest wash due to quality concerns. Escherichia coli O157:H7 has been linked to outbreaks with strawberries but little is known about the survival of E. coli during the growth cycle of strawberries. The survival of E. coli on strawberry plants during growing under greenhouses conditions was evaluated. Soil, leaves, and strawberries (if present) were artificially contaminated with an E. coli surrogate either at the time of planting, first runner removal (4 wk), second runner removal (8 wk), or one week prior to harvest. At harvest E. coli was recovered from the leaves, soil, and strawberries regardless of the contamination time. Time of contamination influenced (P < 0.05) numbers of viable E. coli on the plant. The highest survival of E. coli (P < 0.0001) was detected in soil that was contaminated at planting (4.27 log10 CFU g soil(-1)), whereas, the survival of E. coli was maximal at later contamination times (8 wk and 1 wk prior to harvest) for the leaves (4.40 and 4.68 log10 CFU g leaves(-1)) and strawberries (3.37 and 3.53 log10 CFU strawberry(-1)). Cross contamination from leaves to fruit was observed during this study, with the presence of E. coli on strawberries which had not been present at the time of contamination. These results indicate that good agricultural best practices to avoid contamination are necessary to minimize the risk of contamination of these popular fruit with enteric pathogens. Practices should include soil testing prior to harvest and avoiding contamination of the leaves. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Comparing effects of low levels of herbicides on greenhouse- and field-grown potatoes (Solanum tuberosum L.), soybeans (Glycine max L.), and peas (Pisum sativum L.).

    PubMed

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

    2011-02-01

    Although laboratory toxicology tests are generally easy to perform, cost effective, and readily interpreted, they have been questioned for their environmental relevance. In contrast, field tests are considered realistic while producing results that are difficult to interpret and expensive to obtain. Toxicology tests were conducted on potatoes, peas, and soybeans grown in a native soil in pots in the greenhouse and were compared to plants grown outside under natural environmental conditions to determine toxicological differences between environments, whether different plant developmental stages were more sensitive to herbicides, and whether these species were good candidates for plant reproductive tests. The reproductive and vegetative endpoints of the greenhouse plants and field-grown plants were also compared. The herbicides bromoxynil, glyphosate, MCPA ([4-chloro-2-methylphenoxy] acetic acid), and sulfometuron-methyl were applied at below field application rates to potato plants at two developmental stages. Peas and soybeans were exposed to sulfometuron-methyl at similar rates at three developmental stages. The effective herbicide concentrations producing a 25% reduction in a given measure differed between experimental conditions but were generally within a single order of magnitude within a species, even though there were differences in plant morphology. This study demonstrated that potatoes, peas, and soybeans grown in pots in a greenhouse produce phytotoxicity results similar to those grown outside in pots; that reproductive endpoints in many cases were more sensitive than vegetative ones; and that potato and pea plants are reasonable candidates for asexual and sexual reproductive phytotoxicity tests, respectively. Plants grown in pots in a greenhouse and outside varied little in toxicity. However, extrapolating those toxicity results to native plant communities in the field is basically unknown and in need of research.

  14. [Effects of fertilizer application on greenhouse vegetable yield: a case study of Shouguang].

    PubMed

    Liu, Ping; Li, Yan; Jiang, Li-Hua; Liu, Zhao-Hui; Gao, Xin-Hao; Lin, Hai-Tao; Zheng, Fu-Li; Shi, Jing

    2014-06-01

    Data collected from 51 representative greenhouses of Shouguang through questionnaire survey were analyzed to investigate the effect of chemical fertilizers on vegetable yield, relationship between application of organic manure and yield, and influence factors and evolution rule of fertilizer application rate. The results showed that averages of 3338 kg N x hm(-2), 1710 kg P2O5 x hm(-2) 3446 kg K2O x hm(-2) were applied to greenhouse vegetables annually in Shouguang, 6-14 times as that in the local wheat-maize rotation system. The application rates of chemical N, P, and K fertilizers accounted for about 35%, 49% and 42% of the total input. Increasing application of chemical fertilizers had no significant effect on vegetable yields, while organic manure input significantly increased the vegetable yields. With the increase of greenhouse cultivating time, no significant changes in the input of chemical N, P, and K fertilizers were observed in greenhouse vegetable production while organic manure input decreased significantly. Differences in vegetable species, planting pattern and cultivating time of greenhouses was one of the reasons for large variations in nutrient application rate. In recent more than ten years, organic manure nutrient input increased significantly, chemical N and P fertilizer input presented a downward trend, chemical K fertilizer input increased significantly, and the N/P/K ratio became more and more reasonable in greenhouse vegetable production in Shouguang.

  15. Accumulation of heavy metals by vegetables grown in mine wastes

    SciTech Connect

    Cobb, G.P.; Sands, K.; Waters, M.; Wixson, B.G.; Dorward-King, E.

    2000-03-01

    Lead, cadmium, arsenic, and zinc were quantified in mine wastes and in soils mixed with mine wastes. Metal concentrations were found to be heterogeneous in the wastes. Iceberg lettuce, Cherry Belle radishes, Roma bush beans, and Better Boy tomatoes were cultivated in mine wastes and in waste-amended soils. Lettuce and radishes had 100% survival in the 100% mine waste treatments compared to 0% and 25% survival for tomatoes and beans, respectively. Metal concentrations were determined in plant tissues to determine uptake and distribution of metals in the edible plant parts. Individual soil samples were collected beneath each plant to assess metal content in the immediate plant environment. This analysis verified heterogeneous metal content of the mine wastes. The four plant species effectively accumulated and translocated lead, cadmium, arsenic, and zinc. Tomato and bean plants contained the four metals mainly in the roots and little was translocated to the fruits. Radish roots accumulated less metals compared to the leaves, whereas lettuce roots and leaves accumulated similar concentrations of the four metals. Lettuce leaves and radish roots accumulated significantly more metals than bean and tomato fruits. This accumulation pattern suggests that consumption of lettuce leaves or radish roots from plants grown in mine wastes would pose greater risks to humans and wildlife than would consumption of beans or tomatoes grown in the same area. The potential risk may be mitigated somewhat in humans, as vegetables grown in mine wastes exhibited stunted growth and chlorosis.

  16. Factors affecting radionuclide availability to vegetables grown at Los Alamos

    SciTech Connect

    White, G.C.; Hakonson, T.E.; Ahlquist, A.J.

    1981-07-01

    A field study was conducted in 1977 on /sup 238/ /sup 239/Pu and /sup 137/Cs availability to zucchini squash (Curcurbita melopepo, hybrid seneca) and green bush beans (Phaseolus vulgaris, Landreths stringless) grown under home-garden conditions in an area at Los Alamos National Laboratory used for treated radioactive liquid waste disposal. Radionuclide concentrations were measured as a function of tissue type, height above the soil, fertilization regime, and for the squash, food-cleansing procedures. Analysis of variance procedures was used to analyze the data. Ratios of the concentration of a radionuclide in oven-dried vegetation to dry soil ranged from 0.0004 to 0.116 for the Pu isotopes, and from 0.051 to 0.255 for /sup 137/Cs. Fertilization with cattle manure reduced the Pu concentration ratios by 30% and /sup 137/Cs by 50%. Vegetative parts sampled within 20 cm of the ground surface were contaminated about four times as much as those parts growing further from the ground surface. About 65% of the contamination was removed by washing, indicating the presence of surficial contamination. The 50-year radiation dose commitment to humans consuming vegetables from the garden plot would be less than 0.05 mrem and would be due almost entirely to /sup 137/Cs.

  17. Impact of ozone on quantity and quality of greenhouse-grown potato plants

    SciTech Connect

    Pell, E.J.; Weissberger, W.C.; Speroni, J.J.

    1980-05-01

    The impact of ozone on quality and quantity of greenhouse-grown potatoes was considered. In two experiments conducted in 1977 and 1978, Norland and Kennebec potato plants were grown in a conventional greenhouse. Once every 2 weeks, 10 plants of each cultivar were exposed to 387 ..mu..g/m/sup 3/ (0.20 ppm) ozone for 3 h in a controlled environment chamber. At 120 and 140 days, for Norland and Kennebec, respectively, vines were killed and tubers were harvested. The number and weight of tubers harvested from ozonized plants decreased significantly in both cultivars. Significant decreases in total solids and increases in reducing sugars of tubers from ozone-exposed plants were identified.

  18. Metabolite changes in nine different soybean varieties grown under field and greenhouse conditions.

    PubMed

    Maria John, K M; Natarajan, Savithiry; Luthria, Devanand L

    2016-11-15

    Global food security remains a worldwide concern due to changing climate, increasing population, and reduced agriculture acreages. Greenhouse cultivation increases productivity by extending growing seasons, reducing pest infestations and providing protection against short term drastic weather fluctuations like frost, heat, rain, and wind. In the present study, we examined and compared the metabolic responses of nine soybean varieties grown under field and greenhouse conditions. Extracts were assayed by GC-FID, GC-MS, and LC-MS for the identification of 10 primary (amino acids, organic acids, and sugars) and 10 secondary (isoflavones, fatty acid methyl esters) metabolites. Sugar molecules (glucose, sucrose, and pinitol) and isoflavone aglycons were increased but the isoflavones glucoside content decreased in the greenhouse cultivated soybeans. The amino acids and organic acids varied between the varieties. The results show that clustering (PCA and PLS-DA) patterns of soybean metabolites were significantly influenced by the genetic variation and growing conditions.

  19. [Effects of superphosphate addition on NH3 and greenhouse gas emissions during vegetable waste composting].

    PubMed

    Yang, Yan; Sun, Qin-ping; Li, Ni; Liu, Chun-sheng; Li, Ji-jin; Liu, Ben-sheng; Zou, Guo-yuan

    2015-01-01

    To study the effects of superphosphate (SP) on the NH, and greenhouse gas emissions, vegetable waste composting was performed for 27 days using 6 different treatments. In addition to the controls, five vegetable waste mixtures (0.77 m3 each) were treated with different amounts of the SP additive, namely, 5%, 10%, 15%, 20% and 25%. The ammonia volatilization loss and greenhouse gas emissions were measured during composting. Results indicated that the SP additive significantly decreased the ammonia volatilization and greenhouse gas emissions during vegetable waste composting. The additive reduced the total NH3 emission by 4.0% to 16.7%. The total greenhouse gas emissions (CO2-eq) of all treatments with SP additives were decreased by 10.2% to 20.8%, as compared with the controls. The NH3 emission during vegetable waste composting had the highest contribution to the greenhouse effect caused by the four different gases. The amount of NH3 (CO2-eq) from each treatment ranged from 59.90 kg . t-1 to 81.58 kg . t-1; NH3(CO2-eq) accounted for 69% to 77% of the total emissions from the four gases. Therefore, SP is a cost-effective phosphorus-based fertilizer that can be used as an additive during vegetable waste composting to reduce the NH3 and greenhouse gas emissions as well as to improve the value of compost as a fertilizer.

  20. Greenhouse cultivation mitigates metal-ingestion-associated health risks from vegetables in wastewater-irrigated agroecosystems.

    PubMed

    Cao, Chun; Chen, Xing-Peng; Ma, Zhen-Bang; Jia, Hui-Hui; Wang, Jun-Jian

    2016-08-01

    Wastewater irrigation can elevate metal concentrations in soils and crops and increase the metal-associated health risks via vegetable ingestion in arid and semiarid northwestern China. Here, we investigated the As, Cd, Cr, Cu, Ni, Pb, and Zn concentrations in four vegetable species from Dongdagou and Xidagou farmlands in Baiyin, Gansu, China. We evaluated the effects of irrigation type (Dongdagou: industrial wastewater; Xidagou: domestic wastewater) and cultivation mode (open field and greenhouse) on the vegetable metal concentration, metal partitioning, soil-to-plant bioconcentration factor (BCF), and the health risk index. All stream waters, soils, and vegetables were found most severely polluted by As and Cd, with higher severity in the industrial-wastewater-irrigated Dongdagou than the domestic-wastewater-irrigated Xidagou. All vegetables had higher or, at least, comparable metal mass allocated in the shoot than in the root. Greenhouse cultivation could reduce metal-ingestion-associated health risks from edible vegetable biomass by decreasing the soil to plant bioaccumulation (BCF) and the metal concentration. This effect was always significant for all vegetables within Xidagou, and for carrot within Dongdagou. This mitigation effect of greenhouse cultivation could be attributed to the metal sorption by a higher level of soil organic matter and faster growth rate over metal uptake rate in greenhouses compared to open fields. Such mitigation effect was, however, insignificant for leafy vegetables within Dongdagou, when much more severely polluted water for irrigation was applied in greenhouses compared to open fields within Dongdagou. The present study highlights greenhouse cultivation as a potential mitigating approach to providing less-polluted vegetables for residents in the severely polluted area in addition to the source pollution control. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Characteristics of nitrogen balance in open-air and greenhouse vegetable cropping systems of China.

    PubMed

    Ti, Chaopu; Luo, Yongxia; Yan, Xiaoyuan

    2015-12-01

    Nitrogen (N) loss from vegetable cropping systems has become a significant environmental issue in China. In this study, estimation of N balances in both open-air and greenhouse vegetable cropping systems in China was established. Results showed that the total N input in open-air and greenhouse vegetable cropping systems in 2010 was 5.44 and 2.60 Tg, respectively. Chemical fertilizer N input in the two cropping systems was 201 kg N ha(-1) per season (open-air) and 478 kg N ha(-1) per season (greenhouse). The N use efficiency (NUE) was 25.9 ± 13.3 and 19.7 ± 9.4% for open-air and greenhouse vegetable cropping systems, respectively, significantly lower than that of maize, wheat, and rice. Approximately 30.6% of total N input was accumulated in soils and 0.8% was lost by ammonia volatilization in greenhouse vegetable system, while N accumulation and ammonia volatilization accounted for 19.1 and 11.1%, respectively, of total N input in open-air vegetable systems.

  2. Comparison of furanocoumarin concentrations of greenhouse-grownRuta chalepensis with outdoor plants later transferred to a greenhouse.

    PubMed

    Zobel, A M

    1991-01-01

    Ruta chalepensis contained concentrations of furanocoumarins 25-50% of those found inR. graveolens both in the whole leaf and on its surface. On the leaf surface of plants grown all year indoors in a greenhouse, they increased steadily between November 1 and December 14 on mature upper and lower leaves. New growth upper leaves on December 14 contained less than mature upper leaves. Plants transferred from outdoors to the greenhouse showed decreased concentrations after the first two weeks, followed by recovery both in the whole leaf and on the leaf surface. Proportions of xanthotoxin and bergapten to psoralen changed during the experiment. On the leaf surfaces and in the whole upper leaves of the indoor plants, the proportions were often similar, but in the transferred plants, in most cases, psoralen was less than bergapten or xanthotoxin in the upper leaves and markedly less in the lower leaves. Implications of these findings for possible effects of environmental changes on secondary plant metabolism are discussed.

  3. Warming effects on greenhouse gas fluxes in peatlands are modulated by vegetation composition.

    PubMed

    Ward, Susan E; Ostle, Nicholas J; Oakley, Simon; Quirk, Helen; Henrys, Peter A; Bardgett, Richard D

    2013-10-01

    Understanding the effects of warming on greenhouse gas feedbacks to climate change represents a major global challenge. Most research has focused on direct effects of warming, without considering how concurrent changes in plant communities may alter such effects. Here, we combined vegetation manipulations with warming to investigate their interactive effects on greenhouse gas emissions from peatland. We found that although warming consistently increased respiration, the effect on net ecosystem CO2 exchange depended on vegetation composition. The greatest increase in CO2 sink strength after warming was when shrubs were present, and the greatest decrease when graminoids were present. CH4 was more strongly controlled by vegetation composition than by warming, with largest emissions from graminoid communities. Our results show that plant community composition is a significant modulator of greenhouse gas emissions and their response to warming, and suggest that vegetation change could alter peatland carbon sink strength under future climate change.

  4. Morphometric and genetics properties of pea crops grown in space greenhouse Lada"

    NASA Astrophysics Data System (ADS)

    Levinskikh, M.; Sychev, V.; Podolsky, I.; Gostimsky, S.; Bingham, G.

    Results of the experiments with higher plants performed in greenhouse Svet aboard the MIR space station in 1996-1999 made it evident that the main biological characteristics of plants growth development reproduction and metabolism did not undergo modifications in consequence of microgravity It was shown that at least two ontogenetic cycles of plants could pass in the normal way in this environment However the initial experimental data was insufficient for fiducial conclusions on the delayed effects of cultivating a sequence of plant generations on the background of spaceflight factors Hence these investigations are given precedence in the space life sciences research programs In the period from March 2003 to April 2005 we fulfilled five experimental cultivations of genetically marked dwarf pea species in greenhouse Lada installed in the Russian segment of the International space station The purpose of this series of experiments was to make morphologic and genetic analysis of pea plants grown in successive generations According to our results pea growth and development over the full cycle of ontogenesis from seed to seed taking place in space greenhouse Lada were not different as compared with the ground control plants In addition four successive pea crops gathered in space flight did not loose their reproductive functions and formed viable seeds Genetic analysis of the plants grown from the space and ground seeds produced by the first to fourth successive crops was performed using the methods of

  5. Benzoylphenylurea residues in peppers and zucchinis grown in greenhouses: determination of decline times and pre-harvest intervals by modelling.

    PubMed

    López-López, Trinidad; Martínez-Vidal, José L; Gil-García, María D; Martínez-Galera, María; Rodríguez-Lallena, José A

    2004-02-01

    Residue levels and degradation rates of five benzoylphenylurea insecticides were studied in zucchinis and peppers grown in experimental greenhouses in Almería (Spain). Benzoylphenylurea residues were analyzed by HPLC using on-line post-elution photoirradiation with fluorescence detection. Mathematically defined decline curves were established by determining optimal relationships between benzoylphenylurea residues and time, using different models. The models that best fitted the experimental data were those of first-order for diflubenzuron, triflumuron, hexaflumuron and flufenoxuron in zucchini and RF first-order models for the five insecticides in peppers and for lufenuron in zucchini. Half-life times for the residues on the two vegetables were estimated from the optimal models. In order to guarantee safe consumption of the two vegetables, we have estimated suitable pre-harvest intervals complying with the maximum residue levels established by the Spanish Government. In all cases, such pre-harvest intervals were shorter than those specified by the manufacturers of commercial formulates. Experimental data for the five insecticides in peppers and for lufenuron in zucchini were also fitted to a first-order model. Even though this function was legitimized statistically, estimations of decline times (T/2) and pre-harvest intervals were quite different from those provided by the optimal model.

  6. [Effects of planting years of vegetable solar greenhouse on soil microbial flora and enzyme activities].

    PubMed

    Yang, Qin; Li, Liang

    2013-09-01

    Taking the vegetable solar greenhouses having been planted for 2, 4, 6, 11, 13, 16, and 19 years as test objects, and with the open vegetable field as the control, this paper studied the variations of soil microbial flora and enzyme activities. With the increasing years of planting, the numbers of soil bacteria, actinomycetes, and total microbes in vegetable solar greenhouses decreased after an initial increase, and reached the maximum in the greenhouse of 11 years planting, with a significant increment of 54.8%, 63.7%, and 55.4%, respectively, as compared to the control. The number of soil fungi in the vegetable solar greenhouses increased steadily with increasing planting years, being about 2.2 times higher in the greenhouse of 11 years planting. Among the microbial physiological groups, the numbers of aerobic cellulose-decomposer, aerobic azotobacter, nitrite bacteria, denitrifier, and sulphur reducer showed the same variation trend as the soil bacteria's, and those in the greenhouse of 11 years planting being 1.5, 1.6, 1.9, 1.4, and 1.1 times of the control, respectively. The number of ammonifiers increased after an initial decrease, reached the minimum in the greenhouse of 13 years planting, being only 56.0% of the control. The enzyme activities of soil urease, polyphenol oxidase, sucrase, protease, cellulase, and alkaline phosphatase increased firstly and then decreased with the increasing years of planting, but soil catalase activity was relatively stable. Correlation analysis showed that the numbers of soil bacteria, actinomycetes, and total microbes were significantly positively correlated with all test soil enzyme activities, while the number of soil fungi had significant negative correlation with the activity of soil catalase.

  7. Efficacy of microbial amendments on vegetables in greenhouse and field trials

    USDA-ARS?s Scientific Manuscript database

    Soil amendments, with and without microbes, may affect plant development. Eight-week-old, organically grown, seedlings of a bell, cv. Jupiter, and a non-pungent jalapeño, cv. Pace 105, pepper (both Capsicum annuum L.) were transplanted into pots in a greenhouse using an organic potting medium. One...

  8. Portuguese agriculture and the evolution of greenhouse gas emissions-can vegetables control livestock emissions?

    PubMed

    Mourao, Paulo Reis; Domingues Martinho, Vítor

    2017-07-01

    One of the most serious externalities of agricultural activity relates to greenhouse gas emissions. This work tests this relationship for the Portuguese case by examining data compiled since 1961. Employing cointegration techniques and vector error correction models (VECMs), we conclude that the evolution of the most representative vegetables and fruits in Portuguese production are associated with higher controls on the evolution of greenhouse gas emissions. Reversely, the evolution of the output levels of livestock and the most representative animal production have significantly increased the level of CO2 (carbon dioxide) reported in Portugal. We also analyze the cycle length of the long-term relationship between agricultural activity and greenhouse gas emissions. In particular, we highlight the case of synthetic fertilizers, whose values of CO2 have quickly risen due to changes in Portuguese vegetables, fruit, and animal production levels.

  9. Growth and gas exchange in field-grown and greenhouse-grown Quercus rubra following three years of exposure to enhanced UV-B radiation.

    PubMed

    Bassman, John H; Robberecht, Ronald

    2006-09-01

    Long-term effects of enhanced UV-B radiation were evaluated in field-grown and greenhouse-grown Quercus rubra L. (northern red oak), a species with a multiple flushing shoot growth habit. Seeds were germinated and grown in ambient, twice ambient (2x) or three times ambient (3x) biologically effective UV-B radiation from square-wave (greenhouse) or modulated (field) lamp systems for three growing seasons. Greenhouse plants in the 2x treatment had greater heights and diameters during the later part of the first year and into the second year, but by the third year there were no differences among treatments. There were no significant differences in growth among treatments for field plants. Enhanced UV-B radiation did not significantly reduce total biomass or distribution of biomass in either field or greenhouse plants. Net photosynthesis (3x), leaf conductance (2x and 3x) and water-use efficiency (3x) of greenhouse plants were greater in the enhanced UV-B radiation treatments in the second year but unaffected by the treatments in other years. None of the treatments affected these parameters in field plants. Dark respiration was increased by the 3x treatment in the first and third years in greenhouse plants, and by the 2x treatment during the second year in field plants. Enhanced UV-B had variable effects on apparent quantum yield and light compensation points. Chlorophylls were unaffected by enhanced UV-B radiation in both greenhouse and field conditions. Bulk methanol-extractable UV-absorbing compounds were increased only by the 3x treatment in greenhouse plants during the third year and by the 2x treatment in field plants during the second year. Overall, Q. rubra appears relatively resistant to potentially damaging enhanced UV-B radiation and is unlikely to be negatively impacted even in the predicted worst-case scenarios.

  10. [Estimation model for daily transpiration of greenhouse muskmelon in its vegetative growth period].

    PubMed

    Zhang, Da-Long; Li, Jian-Ming; Wu, Pu-Te; Li, Wei-Li; Zhao, Zhi-Hua; Xu, Fei; Li, Jun

    2013-07-01

    For developing an estimation method of muskmelon transpiration in greenhouse, an estimation model for the daily transpiration of greenhouse muskmelon in its vegetative growth period was established, based on the greenhouse environmental parameters, muskmelon growth and development parameters, and soil moisture parameters. According to the specific environment in greenhouse, the item of aerodynamics in Penman-Monteith equation was modified, and the greenhouse environmental sub-model suitable for calculating the reference crop evapotranspiration in greenhouse was deduced. The crop factor sub-model was established with the leaf area index as independent variable, and the form of the model was linear function. The soil moisture sub-model was established with the soil relative effective moisture content as independent variable, and the form of the model was logarithmic function. With interval sowing, the model parameters were estimated and analyzed, according to the measurement data of different sowing dates in a year. The prediction accuracy of the model for sufficient irrigation and water-saving irrigation was verified, according to measurement data when the relative soil moisture content was 80%, 70%, and 60%, and the mean relative error was 11.5%, 16.2% , and 16.9% respectively. The model was a beneficial exploration for the application of Penman-Monteith equation under greenhouse environment and water-saving irrigation, having good application foreground and popularization value.

  11. Demonstration of a commercial solar greenhouse. Final report

    SciTech Connect

    Figueras, A.

    1982-03-31

    The greenhouse is located in the town of Russell, in St. Lawrence County, New York. It was built to demonstrate the economics of using the solar greenhouse design as a commercial greenhouse growing vegetables for local sale. The design and construction of the greenhouse are briefly described. Records of temperatures monitored and produce grown and sold are included. (BCS)

  12. The effect of floating vegetation on denitrification and greenhouse gas production in wetland mesocosms

    NASA Astrophysics Data System (ADS)

    Jacobs, A. E.; Harrison, J. A.

    2012-12-01

    Anthropogenic intensification of nitrogen (N) loading to aquatic ecosystems is widespread and can lead to the degradation of these systems. Wetlands are important sites for N removal via denitrification, the microbially mediated reduction of reactive nitrate to inert N2 gas, but they can also produce high levels of greenhouse gases. Floating plants play an important role in encouraging denitrification, since they create low oxygen conditions that may favor denitrification. We investigated whether wetland sediments with floating plant cover had higher denitrification and greenhouse gas production rates than wetland sediments without floating plants. Replicate flow-through mesocosms with wetland sediment and water were constructed in a growth chamber to mimic the wetland where the sediment and water were collected. Mesocosm treatments were covered with floating vegetation (duckweed), an opaque tarp, or no cover to determine how cover type affects denitrification and greenhouse gas production and whether biotic or abiotic factors are likely responsible for observed differences. Denitrification and greenhouse gas production rates were calculated by measuring excess N2 gas, methane, and nitrous oxide concentrations in the water column and measuring the gas exchange rates between the water column and the atmosphere. Gas exchange rates were measured using an inert volatile tracer added to the water column and accumulation of gas in the mesocosm headspace. Additional mesocosm experiments were performed to determine how duckweed-dominated wetland systems respond to nitrogen loading and which mechanism for lowering dissolved oxygen concentrations is important in affecting denitrification under floating vegetation. Mesocosms with floating vegetation had lower dissolved oxygen than no cover or tarp-covered mesocosms, which is consistent with field and literature observations. Water flowing out of the mesocosms had statistically lower total nitrogen and nitrate concentrations

  13. Uptake of pharmaceuticals, hormones and parabens into vegetables grown in soil fertilized with municipal biosolids.

    PubMed

    Sabourin, Lyne; Duenk, Peter; Bonte-Gelok, Shelly; Payne, Michael; Lapen, David R; Topp, Edward

    2012-08-01

    Several recent greenhouse studies have established the potential for uptake of human pharmaceuticals from soil fertilized with municipal biosolids into a variety of crops. In the present study, a field experiment was undertaken to evaluate the uptake of organic micropollutants from soil fertilized with municipal biosolids at a regulated application rate into tomatoes, carrots, potatoes and sweet corn produced under normal farming conditions. The vegetables were grown according to farming practices mandated by the province of Ontario Canada, the key feature being a one-year offset between biosolid application and the harvest of crops for human consumption. Biosolids at application, and crop samples following harvest were analyzed for 118 pharmaceuticals and transformation products, 17 hormones or hormone transformation products, and 6 parabens. Analyte concentrations in the biosolids were consistent with those detected in other surveys. Eight of the 141 analytes were detected in one or two crop replicates at concentrations ranging from 0.33 to 6.25 ng/g dry weight, but no analytes were consistently detected above the detection limit in all triplicate treated plots. Overall, this study suggests that the potential for micropollutant uptake into crops under normal farming conditions is low.

  14. Nitrogen removal from the surface runoff of a field scale greenhouse vegetable production system.

    PubMed

    Min, Ju; Lu, Kouping; Zhao, Xu; Sun, Haijun; Zhang, Hailin; Shi, Weiming

    2015-01-01

    Nutrient losses from greenhouse vegetable production systems may impair water quality in the Taihu Lake Region of China. We studied the characteristics of nitrogen (N) lost via runoff from greenhouse vegetable systems and strategies for minimizing N entering water bodies. A two-year experiment at a field scale was conducted to monitor N surface runoff. An eco-ditch (148 m(2)) and a low N input paddy field (135 kg N ha⁻¹, 550 m²) were designed to remove N from the surface runoff of a 25 × 50 m greenhouse vegetable field. The greenhouse was not covered from late June to mid-October each year, and runoff occurred multiple times during this period. Annual total N loss in runoff from the greenhouse vegetable site was 25.3 and 33.5 kg ha⁻¹ in 2010 and 2011, respectively. Nitrate-N was the major form of N lost in the runoff. The average runoff volume was 289 mm (varied from 221 to 357 mm), which contained 15.7 (varied from 3.3 to 39.2 mg L⁻¹) mg L⁻¹ total N. The eco-ditch system and the wetland paddy field (WPF) effectively reduced total N discharge; the removal rates reached 49.9% and 58.7% and the average removal capacities were 12.4 g N m⁻² and 4.1 g N m⁻² in 2010 and 2011, respectively. The combined system of the ecological ditch-WPF removed almost 79% total N in the runoff. Ecological ditch or paddy wetland can be a water management option available to growers in this region to economically reduce pollutants in agricultural runoff.

  15. Molybdenum uptake by forage crops grown on sewage sludge -- Amended soils in the field and greenhouse

    SciTech Connect

    McBride, M.B.; Richards, B.K.; Steenhuis, T.; Spiers, G.

    2000-06-01

    Molybdenum (Mo) is a plant-available element in soils that can adversely affect the health of farm animals. There is a need for more information on its uptake into forage crops from waste materials, such as sewage sludge, applied to agricultural land. Field and greenhouse experiments with several crops grown on long-term sewage sludge-amended soils as well as soils recently amended with dewatered (DW) and alkaline-stabilized (ALK) sludges indicated that Mo supplied from sludge is readily taken up by legumes in particular. Excessive uptake into red clover (Trifolium pratense L.) was seen in a soil that had been heavily amended with sewage sludge 20 yr earlier, where the soil contained about 3 mg Mo/kg soil, three times the background soil concentration. The greenhouse and field studies indicated that Mo can have a long residual availability in sludge-amended soils. The effect of sludge application was to decrease Cu to Mo ratios in legume forages, canola (Brassica napus var. napus) and soybeans [Glycine max (L.) Merr.] below the recommended limit of 2:1 for ruminant diets, a consequence of high bioavailability of Mo and low uptake of Cu added in sludge. Molybdenum uptake coefficients (UCs) for ALK sludge were higher than for DW sludge, presumably due to the greater solubility of Mo measured in the more alkaline sludges and soils. Based on these UCs, it is tentatively recommended that cumulative Mo loadings on forages grown on nonacid soils should not exceed 1.0 kg/ha from ALK sludge or 4.0 kg/ha from DW sludge.

  16. Investigation on diazinon and oxydemeton-methyl residues in cucumbers grown in Kerman greenhouses.

    PubMed

    Ganjeizadeh Rohani, Fatemeh; Mahdavi, Vahideh; Aminaei, M Mehdi

    2014-07-01

    Pesticides are considered as the most polluting substances. The residue of pesticides in agricultural crops, especially in greenhouse harvests, has been reported critical. Cucumber, considered as a vegetable, is an agricultural product which is commonly found in the Iranian food basket. The current study aims to assess the level of diazinon and oxydemeton-methyl existing in cucumbers sampled from Kerman greenhouses. The pesticide residue was extracted by acetone and dichloromethane. The extracts were cleaned up according to the solid-phase extraction method. The pesticide residues were then determined by capillary gas chromatography with nitrogen-phosphorus detection. The recoveries were 83 and 85 %, the limit of detection was 0.028 and 0.034 mg/kg, and the limits of qualification were 0.093 and 0.113 mg/kg for diazinon and oxydemeton-methyl in cucumber samples, respectively. The median of diazinon residue was detected 0.582 mg/kg, which was 11.64 times the national maximum residue limit (MRL) (0.05 mg/kg), and the median for oxydemeton-methyl was 1.910 mg/kg, being 1.91 times the MRL (1 mg/kg).

  17. Bombus huntii, Bombus impatiens and Bombus vosnesenskii (Hymenoptera: Apidae) pollinate greenhouse-grown tomatoes in western North America

    USDA-ARS?s Scientific Manuscript database

    Bumble bees (Bombus) are the primary pollinators of tomatoes grown in greenhouses and can significantly increase fruit weight compared to tomatoes that receive no supplemental pollination. Due to mounting concerns over the transportation of bumble bees outside of their native ranges, several specie...

  18. Phthalic acid esters in soils from vegetable greenhouses in Shandong Peninsula, East China.

    PubMed

    Chai, Chao; Cheng, Hongzhen; Ge, Wei; Ma, Dong; Shi, Yanxi

    2014-01-01

    Soils at depths of 0 cm to 10 cm, 10 cm to 20 cm, and 20 cm to 40 cm from 37 vegetable greenhouses in Shandong Peninsula, East China, were collected, and 16 phthalic acid esters (PAEs) were detected using gas chromatography-mass spectrometry (GC-MS). All 16 PAEs could be detected in soils from vegetable greenhouses. The total of 16 PAEs (Σ16PAEs) ranged from 1.939 mg/kg to 35.442 mg/kg, with an average of 6.748 mg/kg. Among four areas, including Qingdao, Weihai, Weifang, and Yantai, the average and maximum concentrations of Σ16PAEs in soils at depths of 0 cm to 10 cm appeared in Weifang, which has a long history of vegetable production and is famous for extensive greenhouse cultivation. Despite the different concentrations of Σ16PAEs, the PAE compositions were comparable. Among the 16 PAEs, di(2-ethylhexyl) phthalate (DEHP), di-n-octyl phthalate (DnOP), di-n-butyl phthalate (DnBP), and diisobutyl phthalate (DiBP) were the most abundant. Compared with the results on agricultural soils in China, soils that are being used or were used for vegetable greenhouses had higher PAE concentrations. Among PAEs, dimethyl phthalate (DMP), diethyl phthalate (DEP) and DnBP exceeded soil allowable concentrations (in US) in more than 90% of the samples, and DnOP in more than 20%. Shandong Peninsula has the highest PAE contents, which suggests that this area is severely contaminated by PAEs.

  19. Effects of physical agitation on yield of greenhouse-grown soybean

    NASA Technical Reports Server (NTRS)

    Jones, R. S.; Mitchell, C. A.

    1992-01-01

    Agronomic and horticultural crop species experience reductions in growth and harvestable yield after exposure to physical agitation (also known as mechanical stress), as by wind or rain. A greenhouse study was conducted to test the influence of mechanical stress on soybean yield and to determine if exposure to mechanical stress during discrete growth periods has differential effects on seed yield. A modified rotatory shaker was used to apply seismic (i.e., shaking) stress. Brief, periodic episodes of seismic stress reduced stem length, total seed dry weight, and seed number of soybean [Glycine max (L.) Merr.]. Lodging resistance was greater for plants stressed during vegetative growth or throughout vegetative and reproductive growth than during reproductive growth only. Seed dry weight yield was reduced regardless of the timing or duration of stress application, but was lowest when applied during reproductive development. Seismic stress applied during reproductive growth stages R1 to R2 (Days 3 to 4) was as detrimental to seed dry weight accumulation as was stress applied during growth stages R1 to R6 (Days 39 to 42). Seed dry weight per plant was highly correlated with seed number per plant, and seed number was correlated with the seed number of two- and three-seeded pods. Dry weight per 100 seeds was unaffected by seismic-stress treatment. Growth and yield reductions resulting from treatments applied only during the vegetative stage imply that long-term mechanical effects were induced, from which the plants did not fully recover. It is unclear which yield-controlling physiological processes were affected by mechanical stress. Both transient and long-term effects on yield-controlling processes remain to be elucidated.

  20. Effects of physical agitation on yield of greenhouse-grown soybean

    NASA Technical Reports Server (NTRS)

    Jones, R. S.; Mitchell, C. A.

    1992-01-01

    Agronomic and horticultural crop species experience reductions in growth and harvestable yield after exposure to physical agitation (also known as mechanical stress), as by wind or rain. A greenhouse study was conducted to test the influence of mechanical stress on soybean yield and to determine if exposure to mechanical stress during discrete growth periods has differential effects on seed yield. A modified rotatory shaker was used to apply seismic (i.e., shaking) stress. Brief, periodic episodes of seismic stress reduced stem length, total seed dry weight, and seed number of soybean [Glycine max (L.) Merr.]. Lodging resistance was greater for plants stressed during vegetative growth or throughout vegetative and reproductive growth than during reproductive growth only. Seed dry weight yield was reduced regardless of the timing or duration of stress application, but was lowest when applied during reproductive development. Seismic stress applied during reproductive growth stages R1 to R2 (Days 3 to 4) was as detrimental to seed dry weight accumulation as was stress applied during growth stages R1 to R6 (Days 39 to 42). Seed dry weight per plant was highly correlated with seed number per plant, and seed number was correlated with the seed number of two- and three-seeded pods. Dry weight per 100 seeds was unaffected by seismic-stress treatment. Growth and yield reductions resulting from treatments applied only during the vegetative stage imply that long-term mechanical effects were induced, from which the plants did not fully recover. It is unclear which yield-controlling physiological processes were affected by mechanical stress. Both transient and long-term effects on yield-controlling processes remain to be elucidated.

  1. Heavy metals in Australian grown and imported rice and vegetables on sale in Australia: health hazard.

    PubMed

    Rahman, M Azizur; Rahman, Mohammad Mahmudur; Reichman, Suzie M; Lim, Richard P; Naidu, Ravi

    2014-02-01

    Dietary exposure to heavy metals is a matter of concern for human health risk through the consumption of rice, vegetables and other major foodstuffs. In the present study, we investigated concentrations of cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), manganese (Mn), nickel (Ni), lead (Pb), and zinc (Zn) in Australian grown and imported rice and vegetables on sale in Australia. The mean concentrations of Cd, Co, Cr, Cu, Mn, Ni, Pb, and Zn in Australian grown rice were 7.5 µg kg(-1), 21 µg kg(-1), 144 µg kg(-1), 2.9 mg kg(-1), 24.4 mg kg(-1), 166 µg kg(-1), 375 µg kg(-1), and 17.1 mg kg(-1) dry weight (d. wt.), respectively. Except Cd, heavy metal concentrations in Australian grown rice were higher than Bangladeshi rice on sale in Australia. However, the concentrations of Cd, Cr, Cu, and Ni in Indian rice on sale in Australia were higher than Australian grown rice. The concentrations of Cu and Ni in Vietnamese rice, and that of Cd, Cr, Cu, Ni, and Pb in Thai rice on sale in Australia were also higher than Australian grown rice. Heavy metal concentrations in Pakistani rice on sale in Australia were substantially lower than that in Australian grown rice. In Australian grown rice varieties, the concentrations of heavy metals were considerably higher in brown rice varieties than white rice varieties, indicating Australian brown rice as a potential source of dietary heavy metals for Australian consumers. The mean concentrations of heavy metals in Australian grown and Bangladeshi vegetables on sale in Australia were also determined. Some of the Australian grown and Bangladeshi vegetables contained heavy metals higher than Australian standard maximum limits indicating them as potential sources of dietary heavy metals for Australian consumers. Further investigation is required to estimate health risks of heavy metals from rice and vegetables consumption for Australian consumers. © 2013 Published by Elsevier Inc.

  2. [Development of a cultivation technology and selection of leaf vegetable cultures for space greenhouse].

    PubMed

    Levinskikh, M A; Signalova, O B; Derendiaeva, T A; Livanskaia, O G; Nefedova, E L; Sychev, V N; Podo'skiĭ, I G

    2001-01-01

    We plan to perform space experiments on development of a technology for cultivation of leaf vegetables that might be a component of future life support systems for space crews. For this purpose, we are going to fly research greenhouses with the crop area from 0.03 up to 0.1 m2 inside the universal docking module of the ISS Russian segment. To prepare for future space experiments, ground investigations were made in order to compare crop capacity of various artificial soils used to grow leaf vegetables in greenhouse Svet. Useful life of root module Svet can be extended with a new technology based on resupply of fibrous substrate with nutrients. The most effective volume of soil per a plant was determined which sustains high productivity of leaf vegetables in Svet. To select leaf vegetables for in-space cultivation, we conducted investigations of productivity, morphometric and biochemical characteristics, and palatability of 18 cultures including alternative greens highly popular in Japan and China which have been earlier tested neither in laboratory nor in space within the closed eco-system projects. We would prioritize mizuna, pak choi, tatsoi, rapina or broccoli raab, and red giant mustard as objects for in-space investigations.

  3. Dissipation behaviour, processing factors and risk assessment for metalaxyl in greenhouse-grown cucumber.

    PubMed

    Ramezani, Mohammad Kazem; Shahriari, Dariush

    2015-04-01

    Cucumber is widely cultivated in Iran, and the application of systemic and protective fungicides is the main choice of disease treatment, particularly in greenhouse-grown systems. In this research, cucumber fruits were harvested at 1 h to 25 days after the last application to determine the residue and dissipation behaviour of metalaxyl. The effects of peeling and storage (at 3 °C for 4 days) on metalaxyl residue reduction were also assessed. Samples were extracted by the QuEChERS procedure then analysed using liquid chromatography-tandem mass spectrometry. The dissipation of metalaxyl residues approximately fitted a first-order kinetic model, obtaining half-life values of 2.2 and 3.8 days and preharvest interval values of 5.2 and 12.5 days at the recommended dose (2 kg ha(-1) ) and double (4 kg ha(-1) ) dose respectively. The processing factor values for peeling and storage were 0.50 and 0.93 respectively, showing that storage had little effect on residue reduction compared with peeling. The higher content of metalaxyl residues in flesh showed its penetration from the skin into the flesh. The results provided more understanding of fungicide distribution as well as the effective role of peeling in reducing residues in cucumber fruits. © 2014 Society of Chemical Industry.

  4. Biometric analysis of arabica coffee grown in low potassium nutrient solution under greenhouse conditions.

    PubMed

    Moura, W M; Soares, Y J B; Amaral Júnior, A T; Gravina, G A; Barili, L D; Vieira, H D

    2016-09-19

    Genetic parameters and associations between morpho-agronomic traits and nutritional efficiencies of arabica coffee cultivars were estimated to identify promising traits to assist in the selection of coffee genotypes efficient in potassium use, under limiting conditions of this nutrient. The experiment was conducted in a greenhouse with 20 arabica coffee cultivars grown in nutrient solution with a low potassium level (1.5 mM), using a randomized block design with three replicates. The traits evaluated were plant height, number of leaves, number of nodes, internode length, stem diameter, leaf area, rooting efficiency, potassium absorption efficiency, potassium translocation efficiency, biomass production efficiency, and potassium use efficiency. Genetic variability among coffee cultivars for all the evaluated traits was found. The phenotypic variance for all traits showed a higher contribution of genetic variance compared to environmental variance. Plant height, internode length, stem diameter, leaf area, biomass production efficiency, and potassium use efficiency had a genotypic determination coefficient (H2) above 80% and variation index greater than one. Leaf area and stem diameter had significant and positive genetic correlations with rooting, biomass production, and potassium use efficiencies. Stem diameter has great potential for use in breeding programs with a goal of indirect selection of cultivars that have greater potassium use efficiency in environments with restrictions of this nutrient.

  5. Determination of acetamiprid residues in zucchini grown under greenhouse conditions: application to behavioral dynamics.

    PubMed

    Park, Ji-Yeon; Choi, Jeong-Heui; Kim, Bo-Mee; Park, Jong-Hyouk; Cho, Soon-Kil; Ghafar, M W; Abd El-Aty, A M; Shim, Jae-Han

    2011-01-01

    A simple analytical method was developed for the determination of acetamiprid residues in zucchini and zucchini leaves grown under greenhouse conditions using liquid chromatography. Residues were confirmed via tandem mass spectrometry in positive-ion electrospray ionization mode. The calibration curves were linear with correlation coefficients in excess of 0.999. The limits of detection and limits of quantification were 0.01 and 0.03 µg/g and 0.02 and 0.06 µg/g, for the zucchini and zucchini leaves, respectively. For validation purposes, recoveries studies were carried out at low and high levels, yielding recovery rates ranged from 85.7 to 92.2% in zucchini and from 90.5 to 101.9% in zucchini leaves, with a relative standard deviation of <12%. The results demonstrated that the pattern of acetamiprid dissipation followed pseudo first-order kinetics with a half-life of 1.9 and 2.5 days, respectively. The residues in zucchini leaves were substantially higher than in the zucchini plant itself. No residues were detected at 7 days post-application. The results of this study suggest that acetamiprid is acceptable for application in/on zucchini under the recommended dosage conditions.

  6. Annual nitric and nitrous oxide fluxes from Chinese subtropical plastic greenhouse and conventional vegetable cultivations.

    PubMed

    Yao, Zhisheng; Liu, Chunyan; Dong, Haibo; Wang, Rui; Zheng, Xunhua

    2015-01-01

    As intensive vegetable cultivation is rapidly expanding in China and elsewhere worldwide, its environmental consequences on nitrous oxide (N(2)O) and nitric oxide (NO) emissions deserve attention. We measured N(2)O and NO fluxes simultaneously for a full year from Chinese subtropical vegetable fields. Clearly, both N(2)O and NO emissions varied greatly in different vegetable crop seasons within a year, highlighting the importance of whole-year measurement for achieving temporally accurate annual direct emission factors. A revised "hole-in-the-pipe" model well described quantitative relationships between N(2)O plus NO fluxes and soil-specific conditions. Annual background N(2)O and NO emissions were 0.73-5.0 and 0.26-0.56 kg N ha(-1) yr(-1), respectively, for the vegetable cultivations. The farmers' fertilization practice increased N(2)O and NO emissions. Annual direct emission factors for greenhouse and conventional vegetable fields, respectively, were 1.1% and 1.9% for N(2)O, and 0.36% and 0.32% for NO, indicating there is a need to consider a differentiation of emission factors for managed vegetable cultivations. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Production of greenhouse-grown biocrust mosses and associated cyanobacteria to rehabilitate dryland soil function

    USGS Publications Warehouse

    Antoninka, Anita; Bowker, Matthew A.; Reed, Sasha C.; Doherty, Kyle

    2016-01-01

    Mosses are an often-overlooked component of dryland ecosystems, yet they are common members of biological soil crust communities (biocrusts) and provide key ecosystem services, including soil stabilization, water retention, carbon fixation, and housing of N2 fixing cyanobacteria. Mosses are able to survive long dry periods, respond rapidly to precipitation, and reproduce vegetatively. With these qualities, dryland mosses have the potential to be an excellent dryland restoration material. Unfortunately, dryland mosses are often slow growing in nature, and ex situ cultivation methods are needed to enhance their utility. Our goal was to determine how to rapidly produce, vegetatively, Syntrichia caninervis and S. ruralis, common and abundant moss species in drylands of North America and elsewhere, in a greenhouse. We manipulated the length of hydration on a weekly schedule (5, 4, 3, or 2 days continuous hydration per week), crossed with fertilization (once at the beginning, monthly, biweekly, or not at all). Moss biomass increased sixfold for both species in 4 months, an increase that would require years under dryland field conditions. Both moss species preferred short hydration and monthly fertilizer. Remarkably, we also unintentionally cultured a variety of other important biocrust organisms, including cyanobacteria and lichens. In only 6 months, we produced functionally mature biocrusts, as evidenced by high productivity and ecosystem-relevant levels of N2 fixation. Our results suggest that biocrust mosses might be the ideal candidate for biocrust cultivation for restoration purposes. With optimization, these methods are the first step in developing a moss-based biocrust rehabilitation technology.

  8. Sustainability assessment of greenhouse vegetable farming practices from environmental, economic, and socio-institutional perspectives in China.

    PubMed

    Yang, Lanqin; Huang, Biao; Mao, Mingcui; Yao, Lipeng; Niedermann, Silvana; Hu, Wenyou; Chen, Yong

    2016-09-01

    To provide growing population with sufficient food, greenhouse vegetable production has expanded rapidly in recent years in China and sustainability of its farming practices is a major concern. Therefore, this study assessed the sustainability of greenhouse vegetable farming practices from environmental, economic, and socio-institutional perspectives in China based on selected indicators. The empirical data were collected through a survey of 91 farm households from six typical greenhouse vegetable production bases and analysis of environmental material samples. The results showed that heavy fertilization in greenhouse vegetable bases of China resulted in an accumulation of N, P, Cd, Cu, Pb, and Zn in soil, nutrient eutrophication in irrigation water, and high Cd in some leaf vegetables cultivated in acidic soil. Economic factors including decreased crop yield in conventional farming bases, limited and site-dependent farmers' income, and lack of complete implementation of subsidy policies contributed a lot to adoption of heavy fertilization by farmers. Also, socio-institutional factors such as lack of unified management of agricultural supplies in the bases operated in cooperative and small family business models and low agricultural extension service efficiency intensified the unreasonable fertilization. The selection of cultivated vegetables was mainly based on farmers' own experience rather than site-dependent soil conditions. Thus, for sustainable development of greenhouse vegetable production systems in China, there are two key aspects. First, it is imperative to reduce environmental pollution and subsequent health risks through integrated nutrient management and the planting strategy of selected low metal accumulation vegetable species especially in acidic soil. Second, a conversion of cooperative and small family business models of greenhouse vegetable bases to enterprises should be extensively advocated in future for the unified agricultural supplies

  9. 1978 Insect Pest Management Guide: Commercial Vegetable Crops and Greenhouse Vegetables. Circular 897.

    ERIC Educational Resources Information Center

    Illinois Univ., Urbana. Cooperative Extension Service.

    This circular lists suggested uses of insecticides for the control of pests by commercial vegetable farmers. Suggestions are given for selection, dosage and application of insecticides to control pests of cabbage and related crops, beans, cucumbers and other vine crops, tomatoes, potatoes, peppers, corn, and onions. (CS)

  10. 1978 Insect Pest Management Guide: Commercial Vegetable Crops and Greenhouse Vegetables. Circular 897.

    ERIC Educational Resources Information Center

    Illinois Univ., Urbana. Cooperative Extension Service.

    This circular lists suggested uses of insecticides for the control of pests by commercial vegetable farmers. Suggestions are given for selection, dosage and application of insecticides to control pests of cabbage and related crops, beans, cucumbers and other vine crops, tomatoes, potatoes, peppers, corn, and onions. (CS)

  11. Phosphorus saturation and mobilization in two typical Chinese greenhouse vegetable soils.

    PubMed

    Kalkhajeh, Yusef Kianpoor; Huang, Biao; Hu, Wenyou; Holm, Peter E; Bruun Hansen, Hans Christian

    2017-04-01

    Chinese greenhouse vegetable production can cause eutrophication of fresh waters due to heavy use of fertilizers. To address this, phosphorus (P) leaching was compared between two major greenhouse vegetable soils from Jiangsu Province, Southeast China: clayey and acid-neutral Guli Orthic Anthrosols and sandy and alkaline Tongshan Ustic Cambosols. A total of 20 intact soil columns were collected based on differences in total P content varying between 1360 and 11,220 mg kg(-1). Overall, six leaching experiments were carried out with collection of leachates over 24 h. Very high P concentrations, with a mean of 3.43 mg L(-1), were found in the leachates from P rich Tongshan soils. In contrast, P leaching from fine-textured but less P rich Guli soils rarely exceeded the suggested environmental P threshold of 0.1 mg L(-1). Strong linear correlations were found between different soil test P measures (STPs) or degree of P saturations (DPSs) and dissolved reactive P (DRP) for Tongshan soil columns. The correlations with Olsen P (r(2) = 0.91) and DPS based on MehlichIII extractable calcium (DPSM3-Ca) (r(2) = 0.87) were the most promising. An Olsen P value above 41 mg kg(-1) or a DPSM3-Ca above 3.44% led to DRP leaching exceeding 0.1 mg L(-1). Accordingly, more than 80% of Tongshan soils resulted in DRP leaching exceeding the environmental P threshold. In conclusion P rich alkaline sandy soils used for greenhouse vegetable production are at high risk of P mobilization across China.

  12. Lead and Arsenic Uptake by Leafy Vegetables Grown on Contaminated Soils: Effects of Mineral and Organic Amendments

    PubMed Central

    McBride, Murray B.; Simon, Tobi; Tam, Geoffrey; Wharton, Sarah

    2015-01-01

    To assess strategies for mitigating Pb and As transfer into leafy vegetables from contaminated garden soils, we conducted greenhouse experiments using two field-contaminated soils amended with materials expected to reduce metal phytoavailability. Lettuce and mustard greens grown on these soils were analysed by ICP-MS, showing that some Pb and As transfer into the vegetables occurred from both soils tested, but plant Pb concentrations were highly variable among treatment replicates. Soil-to-plant transfer was more efficient for As than for Pb. Contamination of the leaves by soil particles probably accounted for most of the vegetable Pb, since plant Pb concentrations were correlated to plant tissue concentrations of the immobile soil elements Al and Fe. This correlation was not observed for vegetable As concentrations, evidence that most of the soil-to-plant transfer for this toxic metal occurred by root uptake and translocation into the above-ground tissues. A follow-up greenhouse experiment with lettuce on one of the two contaminated soils revealed a lower and less variable foliar Pb concentration than observed in the first experiment, with evidence of less soil particle contamination of the crop. This reduced transfer of Pb to the crop appeared to be a physical effect attributable to the greater biomass causing reduced overall exposure of the above-ground tissues to the soil surface. Attempts to reduce soil Pb and As solubility and plant uptake by amendment at practical rates with stabilizing materials including composts, peat, Ca phosphate, gypsum and Fe oxide, were generally unsuccessful. Only Fe oxide reduced soluble As in the soil, but this effect did not persist. Phosphate amendment rapidly increased soil As solubility but had no measurable effect on either soil Pb solubility or concentrations of Pb or As in the leafy vegetables. The ineffectiveness of these amendments in reducing Pb transfer into leafy vegetables is attributed in this study to the low

  13. Biochemical, biological and histological evaluation of some culinary and medicinal herbs grown under greenhouse and field conditions.

    PubMed

    Yi, Weiguang; Wetzstein, Hazel Y

    2010-04-30

    Increasing evidence supports the potential health benefits of herbal extracts displaying antioxidant, anti-inflammatory and antitumour activities. Environment can have a pronounced effect on phenolic content and antioxidant capacity. The objectives of this study were to evaluate the total phenolic contents and antioxidant capacities of five different herbs grown under greenhouse and field conditions and to assess their potential anti-inflammatory effects. High total polyphenolic (TPP) content (measured by the Folin-Ciocalteu reagent method) and high Trolox equivalent antioxidant capacity (TEAC) were observed in all herbs evaluated. Leaves from thyme, sage, spearmint and peppermint grown in the greenhouse showed significantly higher TPP content and TEAC than those grown under field conditions, with a threefold difference being observed in peppermint. Rosemary, spearmint and peppermint extracts showed stronger inhibition of cyclooxygenase COX-2 than of COX-1. The results show that producing herbs under greenhouse conditions can improve their biological activities by increasing TPP contents and antioxidant capacities. The selective inhibition of COX-2 activity by rosemary, spearmint and peppermint suggests that they may be useful as anti-inflammatory agents with fewer side effects than regular non-steroidal drugs.

  14. Determination of Pesticides Residues in Cucumbers Grown in Greenhouse and the Effect of Some Procedures on Their Residues

    PubMed Central

    LEILI, Mostafa; PIRMOGHANI, Amin; SAMADI, Mohammad Taghi; SHOKOOHI, Reza; ROSHANAEI, Ghodratollah; POORMOHAMMADI, Ali

    2016-01-01

    Background: The objective of this study was to determine the residual concentrations of ethion and imidacloprid in cucumbers grown in greenhouse. The effect of some simple processing procedures on both ethion and imidacloprid residues were also studied. Methods: Ten active greenhouses that produce cucumber were randomly selected. Ethion and imidacloprid as the most widely used pesticides were measured in cucumber samples of studied greenhouses. Moreover, the effect of storing, washing, and peeling as simple processing procedures on both ethion and imidacloprid residues were investigated. Results: One hour after pesticide application; the maximum residue levels (MRLs) of ethion and imidacloprid were higher than that of Codex standard level. One day after pesticide application, the levels of pesticides were decreased about 35 and 31% for ethion and imidacloprid, respectively, which still were higher than the MRL. Washing procedure led to about 51 and 42.5% loss in ethion and imidacloprid residues, respectively. Peeling procedure also led to highest loss of 93.4 and 63.7% in ethion and imidacloprid residues, respectively. The recovery for both target analytes was in the range between 88 and 102%. Conclusion: The residue values in collected samples one hour after pesticides application were higher than standard value. The storing, washing, and peeling procedures lead to the decrease of pesticide residues in greenhouse cucumbers. Among them, the peeling procedure has the greatest impact on residual reduction. Therefore, these procedures can be used as simple and effective processing techniques for reducing and removing pesticides from greenhouse products before their consumption. PMID:28032066

  15. Determination of Pesticides Residues in Cucumbers Grown in Greenhouse and the Effect of Some Procedures on Their Residues.

    PubMed

    Leili, Mostafa; Pirmoghani, Amin; Samadi, Mohammad Taghi; Shokoohi, Reza; Roshanaei, Ghodratollah; Poormohammadi, Ali

    2016-11-01

    The objective of this study was to determine the residual concentrations of ethion and imidacloprid in cucumbers grown in greenhouse. The effect of some simple processing procedures on both ethion and imidacloprid residues were also studied. Ten active greenhouses that produce cucumber were randomly selected. Ethion and imidacloprid as the most widely used pesticides were measured in cucumber samples of studied greenhouses. Moreover, the effect of storing, washing, and peeling as simple processing procedures on both ethion and imidacloprid residues were investigated. One hour after pesticide application; the maximum residue levels (MRLs) of ethion and imidacloprid were higher than that of Codex standard level. One day after pesticide application, the levels of pesticides were decreased about 35 and 31% for ethion and imidacloprid, respectively, which still were higher than the MRL. Washing procedure led to about 51 and 42.5% loss in ethion and imidacloprid residues, respectively. Peeling procedure also led to highest loss of 93.4 and 63.7% in ethion and imidacloprid residues, respectively. The recovery for both target analytes was in the range between 88 and 102%. The residue values in collected samples one hour after pesticides application were higher than standard value. The storing, washing, and peeling procedures lead to the decrease of pesticide residues in greenhouse cucumbers. Among them, the peeling procedure has the greatest impact on residual reduction. Therefore, these procedures can be used as simple and effective processing techniques for reducing and removing pesticides from greenhouse products before their consumption.

  16. Microbial Community and Greenhouse Gas Fluxes from Abandoned Rice Paddies with Different Vegetation.

    PubMed

    Kim, Sunghyun; Lee, Seunghoon; McCormick, Melissa; Kim, Jae Geun; Kang, Hojeong

    2016-10-01

    The area of rice paddy fields has declined continuously in East Asian countries due to abandonment of agriculture and concurrent socioeconomic changes. When they are abandoned, rice paddy fields generally transform into wetlands by natural succession. While previous studies have mainly focused on vegetation shifts in abandoned rice paddies, little information is available about how these changes may affect their contribution to wetland functions. As newly abandoned fields proceed through succession, their hydrology and plant communities often change. Moreover, the relationships between these changes, soil microbial characteristics, and emissions of greenhouse gasses are poorly understood. In this study, we examined changes over the course of secondary succession of abandoned rice paddies to wetlands and investigated their ecological functions through changes in greenhouse gas fluxes and microbial characteristics. We collected gas and soil samples in summer and winter from areas dominated by Cyperaceae, Phragmites, and Sphagnum in each site. We found that CO2 emissions in summer were significantly higher than those in winter, but CH4 and N2O emission fluxes were consistently at very low levels and were similar among seasons and locations, due to their low nutrient conditions. These results suggest that microbial activity and abundance increased in summer. Greenhouse gas flux, soil properties, and microbial abundance were not affected by plant species, although the microbial community composition was changed by plant species. This information adds to our basic understanding of the contribution of wetlands that are transformed from abandoned rice paddy systems.

  17. Influence of Uptake Pathways on the Stereoselective Dissipation of Chiral Neonicotinoid Sulfoxaflor in Greenhouse Vegetables.

    PubMed

    Chen, Zenglong; Dong, Fengshou; Pan, Xinglu; Xu, Jun; Liu, Xingang; Wu, Xiaohu; Zheng, Yongquan

    2016-04-06

    Stereoselectivity is of vital importance in our environment and needs to be taken into account for comprehensive risk assessment and regulatory decisions of chiral neonicotinoid sulfoxaflor. However, little is known about the dissipation of sulfoxaflor stereoisomers with respect to stereoselectivity in plants under greenhouse cultivation. To bridge the knowledge gap, the current study was initiated to investigate the stereoselective degradation of sulfoxaflor in solar greenhouse cucumber and tomato from foliage and root uptake pathways. The stereoselective dissipation of sulfoxaflor was not statistically different between enantiomer pairs from foliage and root pathways of vegetables (P < 0.05). The persistence of sulfoxaflor stereoisomers was consistently prolonged under the foliage uptake pathway (t1/2, 3.38-14.09 days) compared to the root uptake pathway (t1/2, 2.65-5.07 days) in both vegetable fruits. Nevertheless, the concentrations of (+)-sulfoxaflor A and (-)-sulfoxaflor B were both slightly higher than that of their antipode. The tiny difference should be emphasized because it might be magnified to a significant difference by the high-potential bioaccumulation of sulfoxaflor in the food chain.

  18. Arsenic and Lead Uptake by Vegetable Crops Grown on an Old Orchard Site Amended with Compost

    PubMed Central

    McBride, Murray B.; Shayler, Hannah A.; Russell-Anelli, Jonathan M.; Spliethoff, Henry M.; Marquez-Bravo, Lydia G.

    2015-01-01

    The potential for lead (Pb) and arsenic (As) transfer into vegetables was studied on old orchard land contaminated by lead arsenate pesticides. Root (carrot), leafy (lettuce), and vegetable fruits (green bean, tomato) were grown on seven “miniplots” with soil concentrations ranging from near background to ≈ 800 and ≈ 200 mg kg−1 of total Pb and As, respectively. Each miniplot was divided into sub-plots and amended with 0% (control), 5% and 10% (by weight) compost and cropped for 3 years. Edible portions of each vegetable were analyzed for total Pb and As to test the effect of organic matter on transfer of these toxic elements into the crop. Vegetable Pb and As concentrations were strongly correlated to soil total Pb and As, respectively, but not to soil organic matter content or compost addition level. For Pb vegetable concentrations, carrot ≥ lettuce > bean > tomato. For As, lettuce > carrot > bean > tomato. A complementary single-year study of lettuce, arugula, spinach, and collards revealed a beneficial effect of compost in reducing both Pb and As concentrations in leafy vegetables. Comparisons of all measured vegetable concentrations to international health-based standards indicate that tomatoes can be grown without exceeding standards even in substantially Pb- and As-contaminated soils, but carrots and leafy greens may exceed standards when grown in soils with more than 100–200 mg kg−1 Pb. Leafy greens may also exceed health-based standards in gardens where soil As is elevated, with arugula having a particularly strong tendency to accumulate As. PMID:26900187

  19. Arsenic and Lead Uptake by Vegetable Crops Grown on an Old Orchard Site Amended with Compost.

    PubMed

    McBride, Murray B; Shayler, Hannah A; Russell-Anelli, Jonathan M; Spliethoff, Henry M; Marquez-Bravo, Lydia G

    2015-08-01

    The potential for lead (Pb) and arsenic (As) transfer into vegetables was studied on old orchard land contaminated by lead arsenate pesticides. Root (carrot), leafy (lettuce), and vegetable fruits (green bean, tomato) were grown on seven "miniplots" with soil concentrations ranging from near background to ≈ 800 and ≈ 200 mg kg(-1) of total Pb and As, respectively. Each miniplot was divided into sub-plots and amended with 0% (control), 5% and 10% (by weight) compost and cropped for 3 years. Edible portions of each vegetable were analyzed for total Pb and As to test the effect of organic matter on transfer of these toxic elements into the crop. Vegetable Pb and As concentrations were strongly correlated to soil total Pb and As, respectively, but not to soil organic matter content or compost addition level. For Pb vegetable concentrations, carrot ≥ lettuce > bean > tomato. For As, lettuce > carrot > bean > tomato. A complementary single-year study of lettuce, arugula, spinach, and collards revealed a beneficial effect of compost in reducing both Pb and As concentrations in leafy vegetables. Comparisons of all measured vegetable concentrations to international health-based standards indicate that tomatoes can be grown without exceeding standards even in substantially Pb- and As-contaminated soils, but carrots and leafy greens may exceed standards when grown in soils with more than 100-200 mg kg(-1) Pb. Leafy greens may also exceed health-based standards in gardens where soil As is elevated, with arugula having a particularly strong tendency to accumulate As.

  20. Interactions among vegetation, climate, and herbivory control greenhouse gas fluxes in a subarctic coastal wetland

    USGS Publications Warehouse

    Kelsey, K.C.; Leffler, A.J.; Beard, K.H.; Schmutz, Joel A.; Choi, R.T.; Welker, J.M.

    2016-01-01

    High-latitude ecosystems are experiencing the most rapid climate changes globally, and in many areas these changes are concurrent with shifts in patterns of herbivory. Individually, climate and herbivory are known to influence biosphere-atmosphere greenhouse gas (GHG) exchange; however, the interactive effects of climate and herbivory in driving GHG fluxes have been poorly quantified, especially in coastal systems that support large populations of migratory waterfowl. We investigated the magnitude and the climatic and physical controls of GHG exchange within the Yukon-Kuskokwim Delta in western Alaska across four distinct vegetation communities formed by herbivory and local microtopography. Net CO2 flux was greatest in the ungrazed Carex meadow community (3.97 ± 0.58 [SE] µmol CO2 m−2 s−1), but CH4 flux was greatest in the grazed community (14.00 ± 6.56 nmol CH4 m−2 s−1). The grazed community is also the only vegetation type where CH4 was a larger contributor than CO2 to overall GHG forcing. We found that vegetation community was an important predictor of CO2 and CH4 exchange, demonstrating that variation in regional gas exchange is best explained when the effect of grazing, determined by the difference between grazed and ungrazed communities, is included. Further, we identified an interaction between temperature and vegetation community, indicating that grazed regions could experience the greatest increases in CH4 emissions with warming. These results suggest that future GHG fluxes could be influenced by both climate and by changes in herbivore population dynamics that expand or contract the vegetation community most responsive to future temperature change.

  1. Interactions among vegetation, climate, and herbivory control greenhouse gas fluxes in a subarctic coastal wetland

    NASA Astrophysics Data System (ADS)

    Kelsey, K. C.; Leffler, A. J.; Beard, K. H.; Schmutz, J. A.; Choi, R. T.; Welker, J. M.

    2016-12-01

    High-latitude ecosystems are experiencing the most rapid climate changes globally, and in many areas these changes are concurrent with shifts in patterns of herbivory. Individually, climate and herbivory are known to influence biosphere-atmosphere greenhouse gas (GHG) exchange; however, the interactive effects of climate and herbivory in driving GHG fluxes have been poorly quantified, especially in coastal systems that support large populations of migratory waterfowl. We investigated the magnitude and the climatic and physical controls of GHG exchange within the Yukon-Kuskokwim Delta in western Alaska across four distinct vegetation communities formed by herbivory and local microtopography. Net CO2 flux was greatest in the ungrazed Carex meadow community (3.97 ± 0.58 [SE] µmol CO2 m-2 s-1), but CH4 flux was greatest in the grazed community (14.00 ± 6.56 nmol CH4 m-2 s-1). The grazed community is also the only vegetation type where CH4 was a larger contributor than CO2 to overall GHG forcing. We found that vegetation community was an important predictor of CO2 and CH4 exchange, demonstrating that variation in regional gas exchange is best explained when the effect of grazing, determined by the difference between grazed and ungrazed communities, is included. Further, we identified an interaction between temperature and vegetation community, indicating that grazed regions could experience the greatest increases in CH4 emissions with warming. These results suggest that future GHG fluxes could be influenced by both climate and by changes in herbivore population dynamics that expand or contract the vegetation community most responsive to future temperature change.

  2. Biological Control of Diseases of Vegetables Grown Hydroponically in Thailand: Challenge and Opportunity.

    PubMed

    Kanjanamaneesathian, Mana

    2015-01-01

    In Thailand, yield loss due to plant diseases in vegetables grown hydroponically is very high as a result of the growers` lack of knowledge for controlling diseases and their un- willingness to invest in setting-up the proper hydroponic system from the beginning. Severe root rot disease caused by Pythium spp. is frequent and can be anticipated in the hot climate in Thailand. This review focuses on the diseases in temperate lettuces which have been produced hydroponically and have been attacked by plant pathogens, particularly Pythium spp. Biological control of vegetable diseases grown hydroponically has been investigated in Thailand. Research is being carried out to identify effective strains of the antagonists, formulating the applicable products and delivering them appropriately to control the disease. Products of Bacillus subtilis, Chaetomium globosom and Trichoderma harzianum have been recommended for use to control diseases in vegetables grown hydroponically. Control efficacy of these products is varied as the biological products have been used by the growers in the paradigm of using chemical fungicide for disease control in hydroponic production system, overlooking the intrinsic characteristics of the biological control products. The recent patent, which minimizes the effects of sunlight and heat on the nutrient solution without the use of an external energy for cooling the nutrient, should be applied in producing hydroponic vegetables to mitigate poor plant growth and root rot disease outbreak in Thailand.

  3. Effect of soil copper content and pH on copper uptake of selected vegetables grown under controlled conditions.

    PubMed

    Ginocchio, Rosanna; Rodríguez, Patricio H; Badilla-Ohlbaum, Ricardo; Allen, Herbert E; Lagos, Gustavo E

    2002-08-01

    A one-year greenhouse experiment was conducted to study the transfer of copper from contaminated agricultural soils to edible and nonedible structures of lettuce, tomato, and onion plants. Study soils were selected from two basins of central Chile (Santiago and Cachapoal) to represent two similar total soil copper gradients with different pH values. Results showed that free ionic Cu and Cu in saturation extracts were very low in comparison to total Cu contents of study soils (<0.002% and <0.04%, respectively). The concentrations of free ionic copper and of copper in saturation extracts were correlated to total Cu levels and to soil pH. Mean copper concentrations were higher in lettuce than in tomato and onion plants and in vegetables grown on acidic soils of the Cachapoal basin. However, copper levels in edible tissues of tomato and lettuce plants were similar to copper levels described for plants grown on unpolluted soils except for onion bulbs, which had higher values. This indicates that copper translocation to edible, above-ground structures seemed to be well regulated, as their concentrations were fairly constant. The study shows that Cu concentration in study vegetables depends on various factors, including plant species and tissue; site-specific soil factors, such as pH, organic matter, dissolved organic carbon, and conductivity; and several Cu pools, such as total, extractable, and free ionic Cu. Thus, our results support the intensity/capacity concept in that Cu concentration in plants or plant tissues depends not only on the availability of free copper ions in soil solution but also on other soil copper pools that supply the element to the soil solution.

  4. Soil environmental quality in greenhouse vegetable production systems in eastern China: Current status and management strategies.

    PubMed

    Hu, Wenyou; Zhang, Yanxia; Huang, Biao; Teng, Ying

    2017-03-01

    Greenhouse vegetable production (GVP) has become an important source of public vegetable consumption and farmers' income in China. However, various pollutants can be accumulated in GVP soils due to the high cropping index, large agricultural input, and closed environment. Ecological toxicity caused by excessive pollutants' accumulation can then lead to serious health risks. This paper was aimed to systematically review the current status of soil environmental quality, analyze their impact factors, and consequently to propose integrated management strategies for GVP systems. Results indicated a decrease in soil pH, soil salinization, and nutrients imbalance in GVP soils. Fungicides, remaining nutrients, antibiotics, heavy metals, and phthalate esters were main pollutants accumulating in GVP soils comparing to surrounding open field soils. Degradation of soil ecological function, accumulation of major pollutants in vegetables, deterioration of neighboring water bodies, and potential human health risks has occurred due to the changes of soil properties and accumulation of pollutants such as heavy metals and fungicides in soils. Four dominant factors were identified leading to the above-mentioned issues including heavy application of agricultural inputs, outmoded planting styles with poor environmental protection awareness, old-fashion regulations, unreasonable standards, and ineffective supervisory management. To guarantee a sustainable GVP development, several strategies were suggested to protect and improve soil environmental quality. Implementation of various strategies not only requires the concerted efforts among different stakeholders, but also the whole lifecycle assessment throughout the GVP processes as well as effective enforcement of policies, laws, and regulations. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Population dynamics and the economics of invasive species management: the greenhouse whitefly in California-grown strawberries.

    PubMed

    McKee, Gregory J; Goodhue, Rachael E; Zalom, Frank G; Carter, Colin A; Chalfant, James A

    2009-01-01

    In agriculture, relatively few efficacious control measures may be available for an invasive pest. In the case of a new insect pest, insecticide use decisions are affected by regulations associated with its registration, insect population dynamics, and seasonal market price cycles. We assess the costs and benefits of environmental regulations designed to regulate insecticide applications on an invasive species. We construct a bioeconomic model, based on detailed scientific data, of management decisions for a specific invasion: greenhouse whiteflies in California-grown strawberries. The empirical model integrates whitefly population dynamics, the effect of whitefly feeding on strawberry yields, and weekly strawberry price. We use the model to assess the optimality of alternative treatment programs on a simulated greenhouse whitefly population. Our results show that regulations may lead growers to "under-spray" when placed in an economic context, and provide some general lessons about the design of optimal invasive species control policies.

  6. Potential health concerns of trace elements and mineral content in commonly consumed greenhouse vegetables in Isfahan, Iran

    PubMed Central

    Abdi, Mohammad Reza; Rezaee-Ebrahim-Saraee, Khadijeh; Fard, Mehdi Rezvani; Baradaran-Ghahfarokhi, Milad

    2015-01-01

    Background: This study aimed to investigate the potential health concerns of trace elements and mineral content of commonly consumed greenhouse vegetables in Isfahan, Iran. Materials and Methods: Six kinds of greenhouse vegetables namely; Raphanus sativus (Radish), Cucumis sativus (Cucumber), Solanum lycopersicum (Tomato), green Capsicum annuum (Green bell pepper), yellow C. annuum (Yellow bell pepper), and red C. annuum (Red bell pepper) were collected from Isfahan greenhouses, between December 2012 and March 2013. The vegetables were analyzed in order to determine the concentrations of trace elements and trace minerals using instrumental neutron activation analysis (INAA). Results: The results of INAA showed that the concentrations of aluminum, bromine, cobalt, rubidium and strontium of these vegetables were varied from 7.2 to 28.4 mg/kg, 0.6–11.7 mg/kg, 0.1–0.5 mg/kg, 4.2–8.4 mg/kg, and 12.0–141.0 mg/kg, respectively. The trace mineral concentrations of As, Cr, Cs, Sc, Th, and U in all of the samples were less than the defined tolerable upper intake level. Conclusion: The results of this study revealed that considering the measured trace elements and mineral content levels, Isfahan greenhouse vegetables do not impose any serious health harmful effects for individuals in the studied area due to their meal consumptions. PMID:26605243

  7. Effect of carbon dioxide enrichment on health-promoting compounds and organoleptic properties of tomato fruits grown in greenhouse.

    PubMed

    Zhang, Zhiming; Liu, Lihong; Zhang, Min; Zhang, Yongsong; Wang, Qiaomei

    2014-06-15

    The objective of the present study was to evaluate the effect of carbon dioxide (CO2) enrichment on the main health-promoting compounds and organoleptic characteristics of tomato (Solanum lycopersicum) fruits grown in greenhouse. The contents of health-promoting compounds, including lycopene, β-carotene, and ascorbic acid, as well as the flavour, indicated by sugars, titrable acidity, and sugar/acid ratio, were markedly increased in CO2 enrichment fruits. Furthermore, CO2 enrichment significantly enhanced other organoleptic characteristics, including colour, firmness, aroma, and sensory attributes in tomato fruits. The results indicated that CO2 enrichment has potential in promoting the nutritional value and organoleptic characteristics of tomatoes.

  8. A monitoring system for vegetable greenhouses based on a wireless sensor network.

    PubMed

    Li, Xiu-hong; Cheng, Xiao; Yan, Ke; Gong, Peng

    2010-01-01

    A wireless sensor network-based automatic monitoring system is designed for monitoring the life conditions of greenhouse vegetables. The complete system architecture includes a group of sensor nodes, a base station, and an internet data center. For the design of wireless sensor node, the JN5139 micro-processor is adopted as the core component and the Zigbee protocol is used for wireless communication between nodes. With an ARM7 microprocessor and embedded ZKOS operating system, a proprietary gateway node is developed to achieve data influx, screen display, system configuration and GPRS based remote data forwarding. Through a Client/Server mode the management software for remote data center achieves real-time data distribution and time-series analysis. Besides, a GSM-short-message-based interface is developed for sending real-time environmental measurements, and for alarming when a measurement is beyond some pre-defined threshold. The whole system has been tested for over one year and satisfactory results have been observed, which indicate that this system is very useful for greenhouse environment monitoring.

  9. Comparison of the microbiological quality of environmentally friendly and conventionally grown vegetables sold at retail markets in Korea.

    PubMed

    Ryu, Jee-Hoon; Kim, Minju; Kim, Eun-Gyeong; Beuchat, Larry R; Kim, Hoikyung

    2014-09-01

    Fresh produce is usually eaten raw without cooking or heating, which may increase the probability of foodborne infection. The microbiological quality of 11 types of fresh, raw vegetables (romaine lettuce, sesame leaves, crown daisy, garlic chives, iceberg lettuce, cabbage, broccoli, leek, chili pepper, capsicum, and zucchini) purchased at retail markets in Iksan, Korea as affected by cultivation method (environmentally friendly vegetables [organic, pesticide-free, and low-pesticide vegetables] and conventionally grown vegetables) and harvest season was determined. Escherichia coli O157:H7 and Salmonella were not detected in all samples of vegetables tested. Aerobic mesophiles (>6 log cfu/g) were detected in environmentally friendly romaine lettuce and crown daisy and environmentally friendly and conventionally grown garlic chives, which also contained coliforms (>3 log cfu/g). Sesame leaf and crown daisy (regardless of cultivation method), as well as conventionally grown romaine lettuce and leek, contained >1 log cfu/g of E. coli. The overall microbiological quality of environmentally friendly and conventionally grown vegetables was not significantly different (P > 0.05). However, there were seasonal effects on populations of coliforms and generic E. coli on vegetables. The greatest numbers of microorganisms were isolated from environmentally friendly or conventionally grown vegetables purchased in winter. The vegetables, regardless of cultivation method or season, should be subjected to appropriate antimicrobial treatment to enhance their microbial safety. © 2014 Institute of Food Technologists®

  10. The evaluation of trace elements of interest in kidney disease in commonly consumed greenhouse vegetables in Isfahan, Iran: preliminary results

    PubMed Central

    Abdi, Mohammad Reza; Rezaee Ebrahim Saraee, Khadijeh; Rezvani Fard, Mehdi; Khorsandi, Jamshid; Baradaran-Ghahfarokhi, Milad

    2014-01-01

    Trace elements play a significant role in biological processes. The aim of this study was to evaluate the trace elements of interest in kidney disease in commonly consumed greenhouse vegetables in Isfahan, Iran. Six kinds of greenhouse vegetables namely; Raphanus sativus (Radish), Cucumis sativus (Cucamber), Solanum lycopersicum (Tomato), green Capsicum annuum (Green bell pepper), yellow Capsicum annuum (Yellow bell pepper) and red Capsicum annuum (Red bell pepper) were collected from Isfahan greenhouses, between December 2012 to March 2013. The vegetables were analyzed in order to determine the concentrations of trace elements and trace minerals using instrumental neutron activation analysis (INAA). The results of INAA showed that, the concentrations of Fe (Iron), Mn (Manganese) and Zn (Zinc) were varied from <10-50.0 mgkg-1, 6.8-15.0 mgkg-1 and 10.0-23.0 mgkg-1, respectively. The elemental concentration of Fe, Mn and Zn in all of the samples were less than the defined tolerable Upper Intake Level (UIL). The results of this study revealed that, considering the measured trace elements and mineral content levels, Isfahan greenhouse vegetables do not impose any serious health harmful effects for individuals in the studied area due to their meal consumptions. PMID:25340168

  11. Changes in Arctic Vegetation Amplify High-Latitude Warming Through Greenhouse Effect

    NASA Astrophysics Data System (ADS)

    Swann, A.; Fung, I.; Levis, S.; Bonan, G. B.; Doney, S. C.

    2009-12-01

    Changes in vegetation cover are recognized to modify climate and the energy budget of the Earth through changes in albedo in high latitudes and evapotranspiration (ET) in the tropics. In snow-covered regions, the springtime growth of leaves enhances solar absorption because surface albedo is reduced from the albedo of snow (~0.8) towards the albedo of leaves (~0.1). Leaves also play a hydrologic role, transpiring soil water to the atmosphere. It has been suggested that broad-leaf deciduous trees may invade warming tundra more effectively than boreal evergreen trees and these trees have higher rates of transpiration than needle-leaf trees. Here we use a global climate model with an interactive biosphere to investigate the effects of adding deciduous trees on bare ground at high northern latitudes. We find that the top-of-atmosphere radiative imbalance from enhanced transpiration (associated with the expanded forest cover) is 2.4 times larger than the direct forcing due to albedo change from the forest. Albedo change is considered to be the dominant mechanism by which trees directly modify climate at high-latitudes, but our findings suggest an additional mechanism through transpiration. Furthermore, the greenhouse warming by additional water vapor melts sea ice and triggers a positive feedback through changes in ocean albedo and evaporation. Vegetation feedbacks through albedo and transpiration produce a strong warming if they act in combination with sea-ice processes.

  12. Occurrence and risk assessment of phthalate esters (PAEs) in vegetables and soils of suburban plastic film greenhouses.

    PubMed

    Wang, Jun; Chen, Gangcai; Christie, Peter; Zhang, Manyun; Luo, Yongming; Teng, Ying

    2015-08-01

    Phthalate esters (PAEs) are suspected of having adverse effects on human health and have been frequently detected in soils and vegetables. The present study investigated their occurrence and composition in plastic film greenhouse soil-vegetable systems and assessed their potential health risks to farmers exposed to these widespread pollutants. Six priority control phthalates, namely dimethyl phthalate (DMP), diethyl phthalate (DEP), di-n-butyl phthalate (DnBP), butyl benzyl phthalate (BBP), di-(2-ethylhexyl) phthalate (DEHP) and di-n-octyl phthalate (DnOP), were determined in 44 plastic film greenhouse vegetables and corresponding soils. Total PAEs ranged from 0.51 to 7.16mgkg(-1) in vegetables and 0.40 to 6.20mgkg(-1) in soils with average concentrations of 2.56 and 2.23mgkg(-1), respectively. DnBP, DEHP and DnOP contributed more than 90% of the total PAEs in both vegetables and soils but the proportions of DnBP and DnOP in vegetables were significantly (p<0.05) higher than in soils. The average concentrations of PAEs in pot herb mustard, celery and lettuce were >3.00mgkg(-1) but were <2.50mgkg(-1) in the corresponding soils. Stem and leaf vegetables accumulated more PAEs. There were no clear relationships between vegetable and soil PAEs. Risk assessment indicates that DnBP, DEHP and DnOP exhibited elevated non-cancer risk with values of 0.039, 0.338 and 0.038, respectively. The carcinogenic risk of DEHP was about 3.94×10(-5) to farmers working in plastic film greenhouses. Health risks were mainly by exposure through vegetable consumption and soil ingestion.

  13. Contamination, source identification, and risk assessment of polycyclic aromatic hydrocarbons in the soils of vegetable greenhouses in Shandong, China.

    PubMed

    Chai, Chao; Cheng, Qiqi; Wu, Juan; Zeng, Lusheng; Chen, Qinghua; Zhu, Xiangwei; Ma, Dong; Ge, Wei

    2017-08-01

    The concentrations of 16 polycyclic aromatic hydrocarbons (PAHs) were analyzed in soil (n=196) and vegetable (n=30) collected from greenhouses, and also in the soil (n=27) collected from agriculture fields close to the greenhouses in Shandong Province, China. The total PAH concentration (∑16PAH) ranged from 152.2µg/kg to 1317.7µg/kg, within the moderate range in agricultural soils of China. Three-ring PAHs were the dominant species, with Phe (16.3%), Ace (13.1%), and Fl (10.5%) as the major compounds. The concentrations of low molecular weight (LMW ≤3 rings) PAHs were high in the east and north of Shandong, while the concentrations of high molecular weight (HMW ≥4 rings) PAHs were high in the south and west of the study area. The PAH level in soils in industrial areas (IN) was higher than those in transport areas (TR) and rural areas (RR). No significant difference in concentration of ∑16PAH and composition was observed in soils of vegetable greenhouses and field soils. PAH concentration exhibited a weakly positive correlation with alkaline nitrogen, available phosphorus in soil, but a weakly negative correlation with soil pH. However, no obvious correlation was observed between PAH concentration and organic matter of soil, or ages of vegetable greenhouses. ∑16PAH in vegetables ranged from 89.9µg/kg to 489.4µg/kg, and LMW PAHs in vegetables positively correlated with those in soils. The sources of PAHs were identified and quantitatively assessed through positive matrix factorization. The main source of PAHs in RR was coal combustion, while the source was traffic in TR and IN. Moreover, petroleum source, coke source, biomass combustion, or mixed sources also contributed to PAH pollution. According to Canadian soil quality guidelines, exposure to greenhouse soils in Shandong posed no risk to human health. Copyright © 2017. Published by Elsevier Inc.

  14. Bombus huntii, Bombus impatiens, and Bombus vosnesenskii (Hymenoptera: Apidae) Pollinate Greenhouse-Grown Tomatoes in Western North America.

    PubMed

    Strange, James P

    2015-06-01

    Bumble bees (Bombus) are the primary pollinators of tomatoes grown in greenhouses and can significantly increase fruit weight compared with tomatoes that receive no supplemental pollination. More than a million colonies are sold worldwide annually to meet pollination needs. Due to mounting concerns over the transportation of bumble bees outside of their native ranges, several species native to western North American are currently being investigated as potential commercial pollinators. Here, two western, Bombus huntii Greene and Bombus vosnesenskii Radoszkowski, and one eastern species, Bombus impatiens Cresson, are compared for their efficacy as pollinators of greenhouse-grown tomatoes. In two experiments, colonies were placed in greenhouses and compared with control plants that received no supplemental pollination. In the first experiment, seed set was significantly increased with B. huntii pollination in one variety of cherry tomatoes. In the second experiment comparing all three bumble bee species, fruit weight was an average of 25.2 g heavier per fruit pollinated by bees versus the control, and the number of days to harvest was 2.9 d shorter for bee-pollinated fruit. In some rounds of pollination, differences were found among bumble bee species, but these were inconsistent across replicates and not statistically significant overall. Additionally, fruit weight was shown to be highly correlated to fruit diameter and seed set in all tests and, thus, is shown to be a reliable metric for assessing pollination in future studies. These results suggest that commercialization of western bumble bees is a viable alternative to the current practices of moving of nonnative bees into western North America to pollinate tomatoes.

  15. Pseudomonas cichorii as the causal agent of midrib rot, an emerging disease of greenhouse-grown butterhead lettuce in Flanders.

    PubMed

    Cottyn, Bart; Heylen, Kim; Heyrman, Jeroen; Vanhouteghem, Katrien; Pauwelyn, Ellen; Bleyaert, Peter; Van Vaerenbergh, Johan; Höfte, Monica; De Vos, Paul; Maes, Martine

    2009-05-01

    Bacterial midrib rot of greenhouse-grown butterhead lettuce (Lactuca sativa L. var. capitata) is an emerging disease in Flanders (Belgium) and fluorescent pseudomonads are suspected to play an important role in the disease. Isolations from infected lettuces, collected from 14 commercial greenhouses in Flanders, yielded 149 isolates that were characterized polyphasically, which included morphological characteristics, pigmentation, pathogenicity tests by both injection and spraying of lettuce, LOPAT characteristics, FAME analysis, BOX-PCR fingerprinting, 16S rRNA and rpoB gene sequencing, as well as DNA-DNA hybridization. Ninety-eight isolates (66%) exhibited a fluorescent pigmentation and were associated with the genus Pseudomonas. Fifty-five of them induced an HR+ (hypersensitive reaction in tobacco leaves) response. The other 43 fluorescent isolates were most probably saprophytic bacteria and about half of them were able to cause rot on potato tuber slices. BOX-PCR genomic fingerprinting was used to assess the genetic diversity of the Pseudomonas midrib rot isolates. The delineated BOX-PCR patterns matched quite well with Pseudomonas morphotypes defined on the basis of colony appearance and variation in fluorescent pigmentation. 16S rRNA and rpoB gene sequence analyses allowed most of the fluorescent isolates to be allocated to Pseudomonas, and they belonged to either the Pseudomonas fluorescens group, Pseudomonas putida group, or the Pseudomonas cichorii/syringae group. In particular, the isolates allocated to this latter group constituted the vast majority of HR+ isolates and were identified as P. cichorii by DNA-DNA hybridization. They were demonstrated by spray-inoculation tests on greenhouse-grown lettuce to induce the midrib rot disease and could be re-isolated from lesions of inoculated plants. Four HR+ non-fluorescent isolates associated with one sample that showed an atypical midrib rot were identified as Dickeya sp.

  16. Implications of Vegetation Shifts on Greenhouse Gas Production in a Coastal Salt Marsh

    NASA Astrophysics Data System (ADS)

    Ouni, S.; Corbett, J. E.; Peteet, D. M.

    2014-12-01

    Methane production in salt marshes is understudied, although these anaerobic environments store vast amounts of carbon and may release large quantities as climate shifts. Studies show ranges of salt marsh methane emissions that vary widely from 0.4-160 g CH4 m-2 y-1. CH4 production in salt marshes is governed by several variables. Due to high sulfate concentrations in these environments, less CH4 is expected to form and escape from the subsurface. However, vascular plants allow greater amounts of CH4 escape from subsurface porewater and produce more labile organic carbon substrates, which support higher rates of microbial decomposition. Coastal salt marshes are also dominated by various vascular plant species both native and invasive which may allow for greater amounts of CH4 formation and escape than previously thought. To better understand CH4 dynamics in coastal salt marshes, pore water samples were collected from various depths in Piermont salt marsh, NY (40 ̊00' N, 73 ̊55'W), a tidal wetland that has been invaded in the last century by Phragmites australis. Dissolved organic carbon lability was measured, previously developed isotope-mass balance equations were utilized, and root depth and density were analyzed from several vegetation zones. Areas dominated by invasive Phragmites australis vegetation contain deeper and denser root zones and are expected to produce more subsurface methane and release more methane than areas dominated by native vegetation types. This study will allow us to identify zones more likely to contribute greenhouse gases to the atmosphere and increase knowledge of CH4 production and release in coastal salt marshes.

  17. Effects of industrial wastewater on growth and biomass production in commonly grown vegetables.

    PubMed

    Uzma, Syeda; Azizullah, Azizullah; Bibi, Roqaia; Nabeela, Farhat; Muhammad, Uzair; Ali, Imran; Rehman, Zia Ur; Häder, Donat-Peter

    2016-06-01

    In developing countries like Pakistan, irrigation of crops with industrial and municipal wastewater is a common practice. However, the impact of wastewater irrigation on vegetables growth has rarely been studied. Therefore, the present study was conducted to determine the effect of industrial wastewater on the germination and seedling growth of some commonly grown vegetables in Pakistan. Wastewater samples were collected from two different industries (marble industry and match alam factory) at Hayatabad Industrial Estate (HIE) in Peshawar, Pakistan, and their effect on different growth parameters of four vegetables including Hibiscus esculentus, Lactuca sativa, Cucumis sativus, and Cucumis melo was investigated. The obtained results revealed that wastewater from marble industry did not affect seed germination except a minor inhibition in H. esculentus. Effluents from match alam factory stimulated seed germination in C. melo and C. sativus but had no effect on seed germination in the other two vegetables. Wastewater increased root and shoot length in H. esculentus, L. sativa and C. melo, but decreased it in C. sativus. Similarly, differential effects of wastewater were observed on fresh and dry biomass of seedlings in all vegetables. It can be concluded that wastewater may have different effects on different crops, depending upon the nature of wastewater and sensitivity of a plant species to wastewater.

  18. [Cytoembryologic studies of super dwarf wheat grown in "Svet" greenhouse in the ground-based experiments

    NASA Technical Reports Server (NTRS)

    Levinskikh, M. A.; Veselova, T. D.; Il'ina, G. M.; Dzhalilova, Kh Kh; Sychev, V. N.; Derendiaeva, T. A.; Salisbury, F.; Cambell, W.; Bubenheim, D.; Campbell, W. (Principal Investigator)

    1998-01-01

    The Project of scientific programs MIR/SHUTTLE and MIR/NASA was allowed for studying the productional, cytoembryological, morphological, biomechanical and other characteristics of superclub wheat on cultivation in the Svet greenhouse on-board orbital complex. This work was aimed at studying the duration of the complete cycle of ontogenesis of wheat and its individual stages, the peculiarities of forming the reproductive organs, processes, fertilization and formation of the seed production while cultivating in the Svet greenhouse under terrestrial conditions. Superclub wheat has been the object of experimentation. On cultivation of superclub wheat in the Svet greenhouse at designated conditions it was found that the cycle duration "from seed to seed" was 90-97 days. The number of granules in the wheat-ears studied was quite low and ranged from 15 to 30%. Performed studies with applying the light microscopy have indicated that in superclub wheat the embryological processes occur in compliance with those regularities which are described for the other forms of soft wheat.

  19. [Cytoembryologic studies of super dwarf wheat grown in "Svet" greenhouse in the ground-based experiments].

    PubMed

    Levinskikh, M A; Veselova, T D; Il'ina, G M; Dzhalilova, Kh Kh; Sychev, V N; Derendiaeva, T A; Salisbury, F; Cambell, W; Bubenheim, D

    1998-01-01

    The Project of scientific programs MIR/SHUTTLE and MIR/NASA was allowed for studying the productional, cytoembryological, morphological, biomechanical and other characteristics of superclub wheat on cultivation in the Svet greenhouse on-board orbital complex. This work was aimed at studying the duration of the complete cycle of ontogenesis of wheat and its individual stages, the peculiarities of forming the reproductive organs, processes, fertilization and formation of the seed production while cultivating in the Svet greenhouse under terrestrial conditions. Superclub wheat has been the object of experimentation. On cultivation of superclub wheat in the Svet greenhouse at designated conditions it was found that the cycle duration "from seed to seed" was 90-97 days. The number of granules in the wheat-ears studied was quite low and ranged from 15 to 30%. Performed studies with applying the light microscopy have indicated that in superclub wheat the embryological processes occur in compliance with those regularities which are described for the other forms of soft wheat.

  20. Radium and uranium levels in vegetables grown using different farming management systems.

    PubMed

    Lauria, D C; Ribeiro, F C A; Conti, C C; Loureiro, F A

    2009-02-01

    Vegetables grown with phosphate fertilizer (conventional management), with bovine manure fertilization (organic management) and in a mineral nutrient solution (hydroponic) were analyzed and the concentrations of (238)U, (226)Ra and (228)Ra in lettuce, carrots, and beans were compared. Lettuce from hydroponic farming system showed the lowest concentration of radionuclides 0.51 for (226)Ra, 0.55 for (228)Ra and 0.24 for (238)U (Bq kg(-1) dry). Vegetables from organically and conventionally grown farming systems showed no differences in the concentration of radium and uranium. Relationships between uranium content in plants and exchangeable Ca and Mg in soil were found, whereas Ra in vegetables was inversely correlated to the cation exchange capacity of soil, leading to the assumption that by supplying carbonate and cations to soil, liming may cause an increase of U and a decrease of radium uptake by plants. The soil to plant transfer varied from 10(-4) to 10(-2) for (238)U and from 10(-2) to 10(-1) for (228)Ra.

  1. Determination and evaluation of heavy metals in soils under two different greenhouse vegetable production systems in eastern China.

    PubMed

    Tian, Kang; Hu, Wenyou; Xing, Zhe; Huang, Biao; Jia, Mengmeng; Wan, Mengxue

    2016-12-01

    The evaluation of heavy metals (HMs) in greenhouse soils is crucial for both environmental monitoring and human health; thus, it is imperative to determine their concentrations, identify their sources and assess their potential risks. In this study, eight metals (As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn) in 167 surface soils were investigated in two representative greenhouse vegetable systems of China: perennial solar greenhouse (SG) and seasonal plastic greenhouse (PG). The results indicated accumulations of Cd, Cu, Hg and Zn in the SG soils and Cd, Pb, Hg and Zn in the PG soils, with higher concentrations than the background values. In particular, Cd and Hg exhibited high levels of pollution under both GVP systems due to their positive Igeo values. Principle component analysis (PCA) and correlation analysis suggested that Cd, Cu, Hg and Zn in the SG soils and Cd, Hg and Zn in the PG soils were mainly related to intensive farming practices; Pb in the PG soils was significantly affected by atmospheric deposition. The results showed that soil characteristics, in particular soil organic matter, total nitrogen and total phosphorus, exerted significant influence on Hg, Cu, Cd, and Zn under the SG system. However, the HMs in the PG soils were weakly affected by soil properties. Overall, this study provides comparative research on the accumulation, potential risks and sources of HMs in two typical greenhouse soils in China, and our findings suggest that, Cd and Hg in both greenhouse soils could potentially represent environmental problems.

  2. [Treatment effect of biological filtration and vegetable floating-bed combined system on greenhouse turtle breeding wastewater].

    PubMed

    Chen, Chong-Jun; Zhang, Rui; Xiang, Kun; Wu, Wei-Xiang

    2014-08-01

    Unorganized discharge of greenhouse turtle breeding wastewater has brought several negative influences on the ecological environment in the rural area of Yangtze River Delta. Biological filtration and vegetable floating-bed combined system is a potential ecological method for greenhouse turtle breeding wastewater treatment. In order to explore the feasibility of this system and evaluate the contribution of vegetable uptake of nitrogen (N) and phosphorus (P) in treating greenhouse turtle breeding wastewater, three types of vegetables, including Ipomoea aquatica, lettuce and celery were selected in this study. Results showed the combined system had a high capacity in simultaneous removal of organic matter, N and P. The removal efficiencies of COD, NH4(+)-N, TN and TP from the wastewater reached up to 93.2%-95.6%, 97.2%-99.6%, 73.9%-93.1% and 74.9%-90.0%, respectively. System with I. aquatica had the highest efficiencies in N and P removal, followed by lettuce and celery. However, plant uptake was not the primary pathway for TN arid TP removal in the combined system. The vegetable uptake of N and P accounted for only 9.1%-25.0% of TN and TP removal from the wastewater while the effect of microorganisms would be dominant for N and P removal. In addition, the highest amounts of N and P uptake in I. aquatica were closely related with the biomass of plant. Results from the study indicated that the biological filtration and vegetable floating-bed combined system was an effective approach to treating greenhouse turtle breeding wastewater in China.

  3. Large herbivore grazing affects the vegetation structure and greenhouse gas balance in a high arctic mire

    NASA Astrophysics Data System (ADS)

    Falk, Julie Maria; Schmidt, Niels Martin; Christensen, Torben R.; Ström, Lena

    2015-04-01

    Herbivory is an important part of most ecosystems and affects the ecosystems’ carbon balance both directly and indirectly. Little is known about herbivory and its impact on the carbon balance in high arctic mire ecosystems. We hypothesized that trampling and grazing by large herbivores influences the vegetation density and composition and thereby also the carbon balance. In 2010, we established fenced exclosures in high arctic Greenland to prevent muskoxen (Ovibos moschatus) from grazing. During the growing seasons of 2011 to 2013 we measured CO2 and CH4 fluxes in these ungrazed blocks and compared them to blocks subjected to natural grazing. Additionally, we measured depth of the water table and active layer, soil temperature, and in 2011 and 2013 an inventory of the vegetation density and composition were made. In 2013 a significant decrease in total number of vascular plant (33-44%) and Eriophorum scheuchzeri (51-53%) tillers were found in ungrazed plots, the moss-layer and amount of litter had also increased substantially in these plots. This resulted in a significant decrease in net ecosystem uptake of CO2 (47%) and likewise a decrease in CH4 emission (44%) in ungrazed plots in 2013. While the future of the muskoxen in a changing arctic is unknown, this experiment points to a potentially large effect of large herbivores on the carbon balance in natural Arctic ecosystems. It thus sheds light on the importance of grazing mammals, and hence adds to our understanding of natural ecosystem greenhouse gas balance in the past and in the future.

  4. [Effects of fertilization on the P accumulation and leaching in vegetable greenhouse soil].

    PubMed

    Zhao, Ya-jie; Zhao, Mu-qiu; Lu, Cai-yan; Shi, Yi; Chen, Xin

    2015-02-01

    A packed soil column experiment was conducted to investigate the effect of different fertilization practices on phosphorus (P) accumulation and leaching potential in a vegetable greenhouse soil with different fertility levels. The results showed that the leaching loss of total P in the leachates elevated with the increment of leaching time while the accumulative leaching loss of total P was relatively low, indicating P was mainly accumulated in the soil instead of in the leachate. At the end of the leaching experiment, soil fertility and fertilization treatment affected the content of total phosphorus and Olsen-P significantly. Compared with the low-level-fertility soil, the contents of total P and Olsen-P increased by 14.3% and 12.2% in the medium-level-fertility soil, 33.3% and 37.7% in the high-level-fertility soil. Total P in the combined application of poultry manure and chemical fertilizer (M+NPK) was elevated by 5.7% and 4.3%, compared with the NPK and M treatment. Compared with NPK treatment, Olsen-P in M and M + NPK treatments augmented by 13.0% and 3.1%, respectively. Soil total P and Olsen-P mainly accumulated in the 0-10 cm and 10-20 cm soil layers, and much less in the 20-40 cm soil layer.

  5. Changes in Arctic vegetation amplify high-latitude warming through the greenhouse effect.

    PubMed

    Swann, Abigail L; Fung, Inez Y; Levis, Samuel; Bonan, Gordon B; Doney, Scott C

    2010-01-26

    Arctic climate is projected to change dramatically in the next 100 years and increases in temperature will likely lead to changes in the distribution and makeup of the Arctic biosphere. A largely deciduous ecosystem has been suggested as a possible landscape for future Arctic vegetation and is seen in paleo-records of warm times in the past. Here we use a global climate model with an interactive terrestrial biosphere to investigate the effects of adding deciduous trees on bare ground at high northern latitudes. We find that the top-of-atmosphere radiative imbalance from enhanced transpiration (associated with the expanded forest cover) is up to 1.5 times larger than the forcing due to albedo change from the forest. Furthermore, the greenhouse warming by additional water vapor melts sea-ice and triggers a positive feedback through changes in ocean albedo and evaporation. Land surface albedo change is considered to be the dominant mechanism by which trees directly modify climate at high-latitudes, but our findings suggest an additional mechanism through transpiration of water vapor and feedbacks from the ocean and sea-ice.

  6. Changes in Arctic vegetation amplify high-latitude warming through the greenhouse effect

    PubMed Central

    Swann, Abigail L.; Fung, Inez Y.; Levis, Samuel; Bonan, Gordon B.; Doney, Scott C.

    2010-01-01

    Arctic climate is projected to change dramatically in the next 100 years and increases in temperature will likely lead to changes in the distribution and makeup of the Arctic biosphere. A largely deciduous ecosystem has been suggested as a possible landscape for future Arctic vegetation and is seen in paleo-records of warm times in the past. Here we use a global climate model with an interactive terrestrial biosphere to investigate the effects of adding deciduous trees on bare ground at high northern latitudes. We find that the top-of-atmosphere radiative imbalance from enhanced transpiration (associated with the expanded forest cover) is up to 1.5 times larger than the forcing due to albedo change from the forest. Furthermore, the greenhouse warming by additional water vapor melts sea-ice and triggers a positive feedback through changes in ocean albedo and evaporation. Land surface albedo change is considered to be the dominant mechanism by which trees directly modify climate at high-latitudes, but our findings suggest an additional mechanism through transpiration of water vapor and feedbacks from the ocean and sea-ice. PMID:20080628

  7. Determination of chlorfenapyr in leek grown under greenhouse conditions with GC-μECD and confirmation by mass spectrometry.

    PubMed

    Rahman, Md Musfiqur; Choi, Jeong-Heui; Abd El-Aty, A M; Park, Jong Hyouk; Park, Ji-Yeon; Im, Geon-Jae; Shim, Jae-Han

    2012-02-01

    A simple analytical method was developed for the determination of chlorfenapyr residues in leeks grown under greenhouse conditions. Residues were extracted by salting out, analyzed by gas chromatography with microelectron-capture detection, and confirmed via gas chromatography-mass spectrometry. The calibration curves were found to be linear with correlation coefficients (r(2) ) in excess of 0.998. The limits of detection and quantification were 0.0015 and 0.005 mg kg(-1) , respectively. For validation purposes, recovery studies were carried out at low and high levels. Yield recovery rates were 87.27-89.64% with a relative standard deviation <6%. A maximum of 0.32 mg kg(-1) of chlorfenapyr residue was detected in leek sample sprayed three times at 7 day intervals until 7 days prior to harvest. The results of this study suggest that chlorfenapyr is acceptable for application in/on leeks under the recommended dosage regimen.

  8. Induction of plant defense gene expression by plant activators and Pseudomonas syringae pv. tomato in greenhouse-grown tomatoes.

    PubMed

    Herman, M A B; Davidson, J K; Smart, C D

    2008-11-01

    Plant activators provide an appealing management option for bacterial diseases of greenhouse-grown tomatoes. Two types of plant activators, one that induces systemic acquired resistance (SAR) and a second that activates induced systemic resistance (ISR), were evaluated for control of Pseudomonas syringae pv. tomato and effect on plant defense gene activation. Benzothiadiazole (BTH, SAR-inducing compound) effectively reduced bacterial speck incidence and severity, both alone and in combination with the ISR-inducing product. Application of BTH also led to elevated activation of salicylic acid and ethylene-mediated responses, based on real-time polymerase chain reaction analysis of marker gene expression levels. In contrast, the ISR-inducing product (made up of plant growth-promoting rhizobacteria) inconsistently modified defense gene expression and did not provide disease control to the same level as did BTH. No antagonism was observed by combining the two activators as control of bacterial speck was similar to or better than BTH alone.

  9. Effects of washing, peeling, storage, and fermentation on residue contents of carbaryl and mancozeb in cucumbers grown in greenhouses.

    PubMed

    Saeedi Saravi, S S; Shokrzadeh, M

    2016-06-01

    Cucumbers grown in two different greenhouses were exposed to mancozeb and carbaryl at different times. The effects of 10-day preharvest period, water and detergent washing, peeling, predetermined storage period at 4°C (refrigeration), and fermentation on the reduction of residue levels in the plant tissues were investigated. Mancozeb and carbaryl residues in cucumbers were determined by gas chromatography-electron capture detection. Results showed that residue levels in samples, which were collected after 10 days following the pesticide application, were significantly lower than the samples collected after 2 h subsequent to the pesticide application. The culinary applications were effective in reducing the residue levels of the pesticides in cucumbers. As a result, non-fermentative pickling in sodium chloride and acetic acid was the most effective way to reduce the mancozeb and carbaryl residues of the cucumbers.

  10. Occurrence of antibiotics in soils and manures from greenhouse vegetable production bases of Beijing, China and an associated risk assessment.

    PubMed

    Li, Cheng; Chen, Jiayi; Wang, Jihua; Ma, Zhihong; Han, Ping; Luan, Yunxia; Lu, Anxiang

    2015-07-15

    The occurrence of 15 antibiotics in soil and manure samples from 11 large-scale greenhouse vegetable production (GVP) bases in Beijing, China was investigated. Results showed that the greenhouse soils were ubiquitously contaminated with antibiotics, and that antibiotic concentrations were significantly higher in greenhouses than in open field soils. The mean concentrations of four antibiotic classes decreased in the following order: tetracyclines (102μg/kg)>quinolones (86μg/kg)>sulfonamides (1.1μg/kg)>macrolides (0.62μg/kg). This investigation also indicated that fertilization with manure and especially animal feces might be the primary source of antibiotics. A risk assessment based on the calculated risk quotients (RQs) demonstrated that oxytetracycline, chlortetracycline, norfloxacin, ciprofloxacin and enrofloxacin could pose a high risk to soil organisms. These results suggested that the ecological effects of antibiotic contamination in GVP bases and their potential adverse risks on human health need to be given special attention.

  11. Arsenic and heavy metal contamination of vegetables grown in Samta village, Bangladesh.

    PubMed

    Alam, M G M; Snow, E T; Tanaka, A

    2003-06-01

    Drinking of arsenic (As) contaminated well water has become a serious threat to the health of many millions in Bangladesh. However, the implications of contamination of agricultural soils from long-term irrigation with As-contaminated groundwater for phyto-accumulation in food crops, and thence dietary exposure to As, and other metals, has not been assessed previously in Bangladesh. Various vegetables were sampled in Samta village in the Jessore district of Bangladesh, and screened for As, Cd, Pb, Cu and Zn by inductively coupled plasma emission spectrometry (ICP-AES) and inductively coupled plasma mass spectrometry (ICP-MS). These local food products are the basis of human nutrition in this region and of great relevance to human health. The results revealed that the individual vegetables containing the highest mean As concentrations microg x g(-1)) are snake gourd (0.489), ghotkol (0.446), taro (0.440), green papaya (0.389), elephant foot (0.338) and Bottle ground leaf (0.306), respectively. The As concentration in fleshy vegetable material is low. In general, the data show the potential for some vegetables to accumulate heavy metals with concentrations of Pb greater than Cd. Some vegetables such as bottle ground leaf, ghotkol, taro, eddoe and elephant foot had much higher concentrations of Pb. Other leafy and root vegetables, contained higher concentrations of Zn and Cu. Bioconcentration factors (BCF) values, based on dry weight, were below 1 for all metals. In most cases, BCF values decreased with increasing metal concentrations in the soil. From the heavily As-contaminated village in Samta, BCF values for As in ladies finger, potato, ash gourd, brinjal, green papaya, ghotkol and snake gourd were 0.001, 0.006, 0.006, 0.014, 0.030, 0.034 and 0.038, respectively. Considering the average daily intake of fresh vegetables per person per day is only 130 g, all the vegetables grown at Samta had Pb concentrations that would be a health hazard for human consumption

  12. The antioxidant and phenolic profiles of five green vegetables grown in Southern Nigeria.

    PubMed

    Adeosun, Abiola M; Ighodaro, Osasenaga M; Aminu, Abiola O; Ogunlana, Aminat I

    2016-01-01

    Regular consumption of vegetables has been associated with reduced risk of chronic diseases. The phenolic and free radical scavenging properties of five green vegetables grown in southern Nigeria were determined. The phenolic and antioxidant profile of African spinach, bitter leaf, jute leaf, scent leaf and water leaf harvested in the month of August were assessed using standard protocols. The total phenolic content (GAE mg/100 g) of the fresh vegetables ranges from 738.70 ±7.90 in African spinach to 1464.63 ±7.60 in scent leaf. A higher flavonoid content (QE mg/100 g) was found in water leaf (512.07 ±1.47) and jute leaf (510.13 ±2.22) compared to the other vegetables examined; scent leaf (496.51 ±1.31), African spinach (457.40 ±1.50), bitter leaf (371.89 ±0.44). Scent leaf possesses the highest DPPH radical scavenging activity with an EC50 [μg/mL] of 74.64 ±7.73. The other vegetables show a lower EC50 [μg/mL]; jute leaf (125.86 ±11.34) > water leaf (132.43 ±9.43) > bitter leaf (156.02 ±5.43) > African spinach (213.44 ±9.29). The hydroxyl radical scavenging activity (EC50, μg/mL) of the vegetables in order of decreasing activity, was bitter leaf (50.38 ±7.17) > water leaf (103.41 ±6.27) > African spinach   (110.54±8.15) > jute leaf (144.39 ±9.37) > scent leaf (217.51 ±6.90). The total antioxidant capacity (EC50, μg/mL) of the vegetables increases in the following order; African spinach (227.39 ±7.25) < bitter leaf (169.96±6.86) < water leaf (106.31 ±7.66) < scent leaf (65.47 ±14.43) < jute leaf (27.52  ±4.14). The green vegetables possess appreciable phenolic and antioxidant potentials, which underscore their regular consumption as part of healthy Nigerian diet. Principal component analysis (PCA) buttresses the correlations and variations of the aforementioned potential among vegetable species.

  13. Implementation and analysis of an on-farm food safety program for the production of greenhouse vegetables.

    PubMed

    Luedtke, Amber N; Chapman, Benjamin; Powell, Douglas A

    2003-03-01

    Fresh fruits and vegetables are increasingly being recognized as vectors for foodborne illness. In 1998, an on-farm food safety program was developed for the Ontario Greenhouse Vegetable Growers (OGVG) in Ontario, Canada. This hazard analysis critical control point-based system was designed to reduce the potential of microbial contamination along the entire production and distribution process. A previous report (D. A. Powell, M. Bobadilla-Ruiz, A. Whitfield, M. W. Griffiths, and A. Luedtke, J. Food Prot. 65:918-923) outlined the first 2 years of the program; the present report documents the third year of the program's implementation. Through individual on-site grower visits and the microbiological testing of produce and water, the program's OGVG member requirements were determined, and the program's success was assessed. Growers' knowledge, understanding, and awareness of microbial risks associated with fresh produce have increased, and improvements in practices used in greenhouses and packing sheds were noted.

  14. Alternative control of Tetranychus evansi Baker & Pritchard (Acari: Tetranychidae) on tomato plants grown in greenhouses.

    PubMed

    Soto, Alberto; Venzon, Madelaine; Oliveira, Rafael M; Oliveira, Hamilton G; Pallini, Angelo

    2010-01-01

    Tetranychus evansi Baker & Pritchard is an important pest of solanaceous plants, including tomatoes. This mite is characterized by a high reproductive rate, which leads to high population growth in a short period of time causing important economic damage. Control of T. evansi is mainly through synthetic acaricides. In searching for environmentally friendly control measures, we evaluated the efficiency of alternative products to control T. evansi on tomato plants under greenhouse conditions. The products tested were lime sulphur and neem based products. We first estimated the lethal concentration (LC) and instantaneous rate of increase (r i) of T. evansi exposed to different product concentrations in laboratory conditions, and later tested the efficacy of LC95 and the concentrations that restrained mite population growth (r i = 0) in greenhouse conditions. The following treatments were repeated three times: NeemPro (81.0 and 71.6 mg a.i./l), Natuneem (31.1 and 20.4 mg ai/l), Organic Neem (39.1 and 30.4 mg a.i./l), lime sulphur (1.0 and 0.6%) and water (control). For all products, control provided by LC95 was higher than provided for lower concentrations (r i = 0) one day after spraying. However, after five days, for both concentrations, the percentage of T. evansi population reduction was superior to 95% and increased over time. Only plants sprayed with Natuneem (31.1 mg a.i./l) showed symptoms of phytotoxicity. Lime sulphur and neem based products, applied in appropriate concentrations and formulations, bear out as a viable alternative to control T. evansi on tomato plants.

  15. Uptake of {sup 137}Cs in vegetable crops grown on a contaminated lakebed

    SciTech Connect

    Seel, J.F.; Adriano, D.C.; Whicker, F.W.

    1995-06-01

    Mean concentration and plant:soil concentration ratios of {sup 137}Cs were determined for six vegetable crops grown on an exposed, contaminated lakebed of a former reactor cooling reservoir in South Carolina. Each crop species was grown with or without potassium fertilizer. Selected crops were also irrigated with either reservoir water or groundwater. Subsamples of crops were prepared for human consumption before analysis to determine the extent of any loss. Plant:soil concentration ratios (dry basis) ranged from 0.22 to 6.82, values which were substantially higher than those used in generic assessment models. While there was no statistically significant effect of irrigation source or culinary preparation, the effect of potassium-fertilizer was dramatic. In many cases, concentrations of {sup 137}Cs in those plants receiving potassium were less than half of the concentrations in plants that did not receive potassium. Significant differences among species and {sup 131}Cs plant parts for concentrations were observed. Dose/risk calculations for the ingestion of these vegetables by a hypothetical 30-y resident indicates the possibility of a lifetime fatal cancer risk well-above the U.S. Environmental Protection Agency`s regulatory guideline of 10{sup -4}. 33 refs., 4 figs., 2 tabs.

  16. Developing and demonstrating low-energy climate control and production techniques for greenhouse-grown citrus and ornamental crops

    SciTech Connect

    Bodnaruk, W.H. Jr.

    1983-04-01

    The aim of this study was to develop and demonstrate low energy climate control and production techniques for greenhouse grown citrus and ornamental crops. Emphasis was placed on design, fuel efficiency and plant response to warm water soil heating systems using solar energy and LP gas. An energy requirement of 28Btus output per hour per square foot of bed space will provide soil temperature of 70/sup 0/F minimum when air temperatures are maintained at 60/sup 0/F. Soil heating to 70/sup 0/ increased rooting and growth of 8 foliage plant varieties by 25 to 45% compared to plants grown under 60/sup 0/F air temperature conditions. Providing soil heating, however, increased fuel consumption in the central Florida test facilities by 30% in the winters of 1980-81 and 1981-82. Solar tie-in to soil heating systems has the potential of reducing fuel usage. Solar heated water provided 4 hours of soil heating following a good collection day. Decreased in-bed pipe spacing and increased storage capacity should increase the solar percentage to 6 hours.

  17. WholeTree Substrate and Fertilizer Rate in Production of Greenhouse Grown Petunia (Petunia*hybrida Vilm) and marigold (Tagetes patula L.)

    USDA-ARS?s Scientific Manuscript database

    A substrate component (WholeTree) made from loblolly pine (Pinus taeda L.) was evaluated along with starter fertilizer rate in the production of greenhouse-grown petunia (Petunia 'hybrida Vilm. ‘Dreams Purple’) and marigold (Tagetes patula L. ‘Hero Spry’). Loblolly pine from a 12 year old plantation...

  18. Protein, free amino acid, phenloic, ß-carotene, and lycopene content, and antioxidative and cancer cell inhibitory effects of 12 greenhouse-grown commercial cherry tomato varieties

    USDA-ARS?s Scientific Manuscript database

    The content of water, free amino acids, amino acid metabolites, crude protein, the carotene pigments ß-carotene and lycopene, and 9 characterized and 2 incompletely characterized individual phenolic (flavonoid) compounds of 12 greenhouse-grown cherry tomato varieties of various colors (green, yellow...

  19. Spray table evaluation of insecticidal mortality for southern green stink bug, Nezara viridula L. (Pentatomidae: Heteroptera) on greenhouse-grown cotton

    USDA-ARS?s Scientific Manuscript database

    Insecticidal mortality of southern green stink bug, Nezara viridula on greenhouse-grown cotton was investigated on a spray table. Treatments of synthetic pyrethroids and neoniconitoids were compared with those of dicrotophos at 8 oz formulated product per acre as the producer’s standard, and an unt...

  20. Growth and cold hardiness of container-grown Douglas-fir, noble fir, and Sitka spruce seedlings in simulated greenhouse regimes.

    Treesearch

    Peyton W. Owston; T.T. Kozlowski

    1981-01-01

    Seedlings of Pseudotsuga menziesii (Mirb.) Franco, Abies procera Rehd., and Picea sitchensis (Bong.) Carr. were grown for 5 months in growth rooms which simulated hot, warm, or cool growing regimes in greenhouses in western Oregon. Temperature, humidity, light intensity, and photoperiod were changed...

  1. Does consumption of leafy vegetables grown in peri-urban agriculture pose a risk to human health?

    PubMed

    Nabulo, G; Black, C R; Craigon, J; Young, S D

    2012-03-01

    Concentrations of potentially toxic elements were measured in soils and five contrasting tropical leafy vegetables grown in a replicated field trial at five contaminated urban agriculture sites in Kampala City, Uganda. Soil contamination at each site could be tentatively ascribed to known waste disposal practices. There was considerable variation in metal uptake between vegetable types. Washing leafy vegetables reduced chromium and lead concentrations but exogenous contamination of leaves also depended on vegetable type, with Gynandropsis gynandra L. showing a marked tendency to accumulate Pb and Cr. For the worst case scenario of children consuming unwashed vegetables, some metal 'hazard quotient' (HQ) limits (1.0) were violated at four of the five sites studied. For the 25 'site-vegetable' combinations assessed, the HQ for Pb exceeded 1.0 in 36% of cases. A vegetable-specific site screening tool based on soil extraction with 0.01 M CaCl(2) and extrapolation to provide HQ values was assessed.

  2. Structural analysis of Gossypium hirsutum fibers grown under greenhouse and hydroponic conditions.

    PubMed

    Natalio, Filipe; Tahir, Muhammad Nawaz; Friedrich, Norman; Köck, Margret; Fritz-Popovski, Gerhard; Paris, Oskar; Paschke, Reinhard

    2016-06-01

    Cotton is the one of the world's most important crops. Like any other crop, cotton growth/development and fiber quality is highly dependent on environmental factors. Increasing global weather instability has been negatively impacting its economy. Cotton is a crop that exerts an intensive pressure over natural resources (land and water) and demands an overuse of pesticides. Thus, the search for alternative cotton culture methods that are pesticide-free (biocotton) and enable customized standard fiber quality should be encouraged. Here we describe a culture of Gossypium hirsutum ("Upland" Cotton) utilizing a greenhouse and hydroponics in which the fibers are morphological similar to conventional cultures and structurally fit into the classical two-phase cellulose I model with 4.19nm crystalline domains surrounded by amorphous regions. These fibers exhibit a single crystalline form of cellulose I-Iß, monoclinic unit cell. Fiber quality bulk analysis shows an improved length, strength, whiteness when compared with soil-based cultures. Finally, we show that our fibers can be spun, used for production of non-woven fabrics and indigo-vat stained demonstrating its potential in industrial and commercial applications. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. Dissipation of six fungicides in greenhouse-grown tomatoes with processing and health risk.

    PubMed

    Jankowska, Magdalena; Kaczynski, Piotr; Hrynko, Izabela; Lozowicka, Bozena

    2016-06-01

    Greenhouse studies were conducted to evaluate the dissipation rate kinetics and estimate the behavior of selected pesticides after washing, peeling, simmering, and canning of tomato expressed as processing factor (PF). Two varieties (Marissa and Harzfeuer) were treated by six fungicides: azoxystrobin, boscalid, chlorothalonil, cyprodinil, fludioxonil, and pyraclostrobin at single and double dose and risk assessment defined as hazard quotient was performed. The QuEChERS method was used for sample preparation followed by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). The dissipation of fungicides approximately fitted to a first-order kinetic model, with half-life values ranging from 2.49 and 2.67 days (cyprodinil) to 5.00 and 5.32 days (chlorothalonil) for Marissa and Harzfeuer variety, respectively. Results from processing studies showed that treatments have significant effects on the removal of the studied fungicides for both varieties. The PFs were generally less than 1 (between 0.01 and 0.90) and did not depend on variety. The dietary exposure assessed based on initial deposits of application at single and double dose on tomatoes and concentration after each process with PF correction showed no concern to consumer health. Our results would be a useful tool for monitoring of fungicides in tomatoes and provide more understanding of residue behavior and risk posed by these fungicides.

  4. The gravitropic response dynamics of wheat plants grown inside hemispherical greenhouse prototype

    NASA Astrophysics Data System (ADS)

    Zyablova, Natalya; Berkovich, Yuliy A.; Skripnikov, Alexander

    The characters of time course of gravicurvature (TCGC) of the 3-day wheat coleoptiles after a change in their orientation within the gravity field in dark and under red light are studied. It was found that maximal curvature angle and average rate of gravicurvature took place after 90 degrees of gravistimulation turn. Duration of the TCGC was registered in the range from 130 to 195 minutes. The estimates of red light (PPF of 30 µmol.m-2.s-1and 300 µmol.m-2.s-1) influence on 3-days coleoptiles TCGC are obtained. The reorganization of microtubules in dark and light during TCGC of wheat coleoptiles after changing their orientation from vertical to different angles is studied. The parameters of growth and development of wheat, cultivated during 5 weeks in rotating growth chamber of hemispherical on-ground prototype of space greenhouse were compared with stationary control crop. The wheat crop was cultivated under the hemispherical red-blue LEDs assembly with PPF of around 300 µmol.m-2.s-1. The plant growth chamber had diameter of 600mm and rotated 3 rph around of 2 perpendicular axes. Nutrient solution supply system regulated water potential in the range of (1,0 ± 0,45) kPa. The experiment showed that integral wheat gravitropic reactions inside rotating growth chamber under chosen illumination had not significant effect on growth and development of the plants.

  5. Phthalate esters in soil, plastic film, and vegetable from greenhouse vegetable production bases in Beijing, China: Concentrations, sources, and risk assessment.

    PubMed

    Li, Cheng; Chen, Jiayi; Wang, Jihua; Han, Ping; Luan, Yunxia; Ma, Xupu; Lu, Anxiang

    2016-10-15

    The increased use of plastic film in greenhouse vegetable production (GVP) could result in phthalate ester (PAE) contamination in vegetables. However, limited information is currently available on their occurrence and associated potential risks in GVP systems. The present study documents the occurrence and composition of 15 PAEs in soil, plastic film, and vegetable samples from eight large-scale GVP bases in Beijing, China. Results showed that PAEs are ubiquitous contaminants in these GVP bases. Total PAE concentrations ranged from 0.14 to 2.13mg/kg (mean 0.99mg/kg) in soils and from 0.15 to 6.94mg/kg (mean 1.49mg/kg) in vegetables. Di (2-ethylhexyl) phthalate, di-n-butyl phthalate, and diisobutyl phthalate were the most abundant components, which accounted for >90% of the total PAEs. This investigation also indicated that the widespread application of plastic film in GVP systems may be the primary source of these PAEs. The non-cancer and carcinogenic risks of target PAEs were estimated based on the exposures of vegetable intake. The hazard quotients of PAE in all vegetable samples were lower than 1 and the carcinogenic risks were also at acceptable levels for consumers. The data in this study can provide valuable information to understand the status of potential pollutants, specifically PAEs, in GVP systems. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Flow injection assessment of nitrate contents in fresh and cooked fruits and vegetables grown in Fiji.

    PubMed

    Prasad, Surendra; Chetty, Adrian A

    2011-10-01

    Nitrates form part of the essential chemistry of soils and plants. Thus, plant roots are able to absorb nitrate directly from the soil. It has been discovered that human nitrate intake is mainly from vegetables. Vegetables play an important role in human nutrition since they are an outstanding source for vitamins, minerals, and biologically active compounds. In risk assessment of nitrate contents, this study reports the nitrate levels of 8 commonly consumed fruits and vegetables grown in Fiji, tomato (Lycopersicon esculentum), eggplant (Solanum melongena), capsicum (Capsicum annuum var. grossum), breadfruit (Artocarpus altilis), long bean (Vigna sesquipedalis), jackfruit (A. heterophyllus), pumpkin (Cucurbita pepo), and cucumber (Cucumis sativus). The effects of different types of cooking methods, baking, boiling, and frying, have also been studied. The validated flow injection analysis technique has been used to quantify the nitrate-N levels in the chosen products following nitrate extraction using the activated carbon technique. The mean values of nitrate levels in fresh products ranged from 25.83 to 281.02 mg NO(3) (-) kg(-1) . The study shows that boiling reduced nitrate contents by 65.37% to 25.25%. The frying in soy bean oil elevated nitrate contents from 354.79% to 86.69%, but after baking, nitrate contents remained almost constant with slight increasing trend in the case of tomato (19.97%). The nitrate levels published in the literature for the same types of fruits and vegetables studied have also been reviewed and compared. The average nitrate-N values were comparable or lower than overseas data, but did not present unpredictably high values, that is, they were below the risk level. © 2011 Institute of Food Technologists®

  7. Response of nitric and nitrous oxide fluxes to N fertilizer application in greenhouse vegetable cropping systems in southeast China

    PubMed Central

    Zhang, Yaojun; Lin, Feng; Jin, Yaguo; Wang, Xiaofei; Liu, Shuwei; Zou, Jianwen

    2016-01-01

    It is of great concern worldwide that active nitrogenous gases in the global nitrogen cycle contribute to regional and global-scale environmental issues. Nitrous oxide (N2O) and nitric oxide (NO) are generally interrelated in soil nitrogen biogeochemical cycles, while few studies have simultaneously examined these two gases emission from typical croplands. Field experiments were conducted to measure N2O and NO fluxes in response to chemical N fertilizer application in annual greenhouse vegetable cropping systems in southeast China. Annual N2O and NO fluxes averaged 52.05 and 14.87 μg N m−2 h−1 for the controls without N fertilizer inputs, respectively. Both N2O and NO emissions linearly increased with N fertilizer application. The emission factors of N fertilizer for N2O and NO were estimated to be 1.43% and 1.15%, with an annual background emission of 5.07 kg N2O-N ha−1 and 1.58 kg NO-N ha−1, respectively. The NO-N/N2O-N ratio was significantly affected by cropping type and fertilizer application, and NO would exceed N2O emissions when soil moisture is below 54% WFPS. Overall, local conventional input rate of chemical N fertilizer could be partially reduced to attain high yield of vegetable and low N2O and NO emissions in greenhouse vegetable cropping systems in China. PMID:26848094

  8. Response of nitric and nitrous oxide fluxes to N fertilizer application in greenhouse vegetable cropping systems in southeast China.

    PubMed

    Zhang, Yaojun; Lin, Feng; Jin, Yaguo; Wang, Xiaofei; Liu, Shuwei; Zou, Jianwen

    2016-02-05

    It is of great concern worldwide that active nitrogenous gases in the global nitrogen cycle contribute to regional and global-scale environmental issues. Nitrous oxide (N2O) and nitric oxide (NO) are generally interrelated in soil nitrogen biogeochemical cycles, while few studies have simultaneously examined these two gases emission from typical croplands. Field experiments were conducted to measure N2O and NO fluxes in response to chemical N fertilizer application in annual greenhouse vegetable cropping systems in southeast China. Annual N2O and NO fluxes averaged 52.05 and 14.87 μg N m(-2) h(-1) for the controls without N fertilizer inputs, respectively. Both N2O and NO emissions linearly increased with N fertilizer application. The emission factors of N fertilizer for N2O and NO were estimated to be 1.43% and 1.15%, with an annual background emission of 5.07 kg N2O-N ha(-1) and 1.58 kg NO-N ha(-1), respectively. The NO-N/N2O-N ratio was significantly affected by cropping type and fertilizer application, and NO would exceed N2O emissions when soil moisture is below 54% WFPS. Overall, local conventional input rate of chemical N fertilizer could be partially reduced to attain high yield of vegetable and low N2O and NO emissions in greenhouse vegetable cropping systems in China.

  9. Response of nitric and nitrous oxide fluxes to N fertilizer application in greenhouse vegetable cropping systems in southeast China

    NASA Astrophysics Data System (ADS)

    Zhang, Yaojun; Lin, Feng; Jin, Yaguo; Wang, Xiaofei; Liu, Shuwei; Zou, Jianwen

    2016-02-01

    It is of great concern worldwide that active nitrogenous gases in the global nitrogen cycle contribute to regional and global-scale environmental issues. Nitrous oxide (N2O) and nitric oxide (NO) are generally interrelated in soil nitrogen biogeochemical cycles, while few studies have simultaneously examined these two gases emission from typical croplands. Field experiments were conducted to measure N2O and NO fluxes in response to chemical N fertilizer application in annual greenhouse vegetable cropping systems in southeast China. Annual N2O and NO fluxes averaged 52.05 and 14.87 μg N m‑2 h‑1 for the controls without N fertilizer inputs, respectively. Both N2O and NO emissions linearly increased with N fertilizer application. The emission factors of N fertilizer for N2O and NO were estimated to be 1.43% and 1.15%, with an annual background emission of 5.07 kg N2O-N ha‑1 and 1.58 kg NO-N ha‑1, respectively. The NO-N/N2O-N ratio was significantly affected by cropping type and fertilizer application, and NO would exceed N2O emissions when soil moisture is below 54% WFPS. Overall, local conventional input rate of chemical N fertilizer could be partially reduced to attain high yield of vegetable and low N2O and NO emissions in greenhouse vegetable cropping systems in China.

  10. Anti-tumorigenic activity of five culinary and medicinal herbs grown under greenhouse conditions and their combination effects.

    PubMed

    Yi, Weiguang; Wetzstein, Hazel Y

    2011-08-15

    Herbs and spices have been used as food preservatives, flavorings, and in traditional medicines for thousands of years. More and more scientific evidence supports the medicinal properties of culinary herbs. Colon cancer is the third leading cause of cancer death in the USA, and the fourth most common form of cancer worldwide. The objectives of this study were to evaluate the antitumor activity of five selected herbs grown under greenhouse conditions, and to study the potential synergistic effects among different herbal extract combinations. Thyme, rosemary, sage, spearmint, and peppermint extracts significantly inhibited SW-480 colon cancer cell growth, with sage extracts exhibiting the highest bioactivity, with 50% inhibition at 35.9 µg mL⁻¹, which was equivalent to 93.9 µg dried leaves mL⁻¹ of culture medium. Some mixtures of different herbal extracts had combination effects on cancer cell growth. The inhibitory effects of peppermint + sage combinations at a 1:1 ratio were significantly higher than rosemary + sage combinations at 1:1 ratio, although peppermint extracts showed lower inhibition than rosemary extracts. Extracts from herb species (thyme, rosemary, sage, spearmint and peppermint) can significantly inhibit the growth of human colon cancer cells. Mixtures of herb extracts can have combination effects on cancer cell growth. The study suggests that these five herbs may have potential health benefits to suppress colon cancer. Copyright © 2011 Society of Chemical Industry.

  11. Assessment of diesel-contaminated domestic wastewater treated by constructed wetlands for irrigation of chillies grown in a greenhouse.

    PubMed

    Al-Isawi, Rawaa H K; Scholz, Miklas; Al-Faraj, Furat A M

    2016-12-01

    In order to avoid environmental pollution and eliminate the need for using fertiliser, this study assessed for the first time the optimum performance of mature (in operation since 2011) vertical flow constructed wetlands in treating domestic wastewater (with and without hydrocarbon) and the subsequent recycling of the outflow to irrigate chillies (De Cayenne; Capsicum annuum (Linnaeus) Longum Group 'De Cayenne') grown in a greenhouse. Various variables were investigated to assess the treatment performance. Concerning chilli fruit numbers, findings showed that the highest fruit yields for all wetland filters were associated with those that received inflow wastewater with a high loading rate, reflecting the high nutrient availability in treated wastewater, which is of obvious importance for yield production. Findings also indicated that wetlands without hydrocarbon, small aggregate size, low contact time and low inflow loading rate provided high marketable yields (expressed in economic return). In comparison, chillies irrigated by filters with hydrocarbon contamination, small aggregate size, high contact time and high loading rate also resulted in high marketable yields of chillies, which pointed out the role of high contact time and high inflow load for better diesel degradation rates.

  12. Variation in concentrations of the fungicides tebuconazole and dichlofluanid following successive applications to greenhouse-grown lettuces.

    PubMed

    Rial-Otero, Raquel; Arias-Estévez, Manuel; López-Periago, Eugenio; Cancho-Grande, Beatriz; Simal-Gándara, Jesús

    2005-06-01

    Residual levels and degradation rates of tebuconazole and dichlofluanid in lettuce plants grown in a greenhouse under agricultural conditions typical of northwestern Spain were studied. Lettuce plants were sprayed four times with a homogeneous 0.2% aqueous solution of Folicur Combi (wettable powder containing 40% dichlofluanid and 10% tebuconazole) at a rate of 2500 g/ha. Samples were collected 1, 5, and 9 days after the first two applications and at times ranging from 1 to 27 days after the last two applications. All samples were stored in a refrigerator at 4 degrees C. Fungicide levels were determined by solid-liquid extraction (SLE) followed by gas chromatography and mass spectrometry detection (GC-MSD). Recovery was good for tebuconazole (98%) but low for dichlofluanid (29%); precision was good (<10% for both analytes), and quantification limits were low (<1.5 mg/kg). Seven days after the last application, dichlofluanid levels were below the maximum allowed limit established in Spain (10 mg/kg), but tebuconazole levels were above the corresponding limit (5 mg/kg). Tebuconazole concentration dynamics was accurately fitted by zeroth- or combined first- and zeroth-order models (depending on variety), but modeling of the behavior of dichlofluanid was less satisfactory, probably due to its instability.

  13. Cadmium, lead and mercury in fresh and boiled leafy vegetables grown in Lagos, Nigeria.

    PubMed

    Bakare, S; Denloye, A A B; Olaniyan, F O

    2004-12-01

    Vegetables, eaten fresh or boiled, are an important diet relished in many local Nigerian cuisines and delicacies. Increasing their production has therefore become a prime focus of governments in Nigeria. In the process of production, metals capable of impairing the health of consumers are inadvertently picked up. Studies were therefore conducted to determine the presence of cadmium (Cd), lead (Pb) and mercury (Hg) in fresh and boiled leafy vegetables grown in farms close (proximal) to highways (PS) and those distant from highways (DS). Composite samples of fresh lettuce (Lactuca sativa), fresh Amaranthus (Amaranthus speciosa), boiled A. speciosa, soil, irrigation water, and manure from farms located at the two sites were analyzed by Atomic Absorption Spectrophotometry (AAS). The results show that the fresh vegetables grown on sites close to highways (PS) had higher levels of Cd and Pb (0.313 microg g(-1), 16.933 microg g(-1) for Cd and Pb respectively in fresh Amaranthus, and 0.877 microg g(-1), 16.833 microg g(-1) for Cd and Pb respectively in Raw Lettuce) than those from DS farms (0.20 microg g(-1), 8.33 microg g(-1) for Cd and Pb respectively in fresh Amaranthus and 0.266 microg g(-1), 8.00 microg g(-1) for Cd and Pb respectively in Raw Lettuce). The irrigation water at the PS farms contained more Pb but similar levels of Cd and Hg. Soil from the PS was slightly more acidic (pH = 6.32 + 0.08) than those from the DS (pH = 6.49 + 0.02). Soils of PS farms gave very high Pb levels (4.13 microg g(-1)). Boiling had an effect on the levels of Cd and Pb but not Hg in Amaranthus, irrespective of the site of production. Cadmium (Cd) increased from 0.2 microg g(-1) to 1.036 microg g(-1) before and after boiling respectively in DS samples, while it increased from 0.3131 microg g(-1) to 1.037 microg g(-1) in samples from PS farms before and after boiling respectively. The level followed similar trend. Pb increased from 8.33 microg g(-1) to 5.667 microg g(-1) before and after

  14. Photosynthesis rates, growth, and ginsenoside contents of 2-yr-old Panax ginseng grown at different light transmission rates in a greenhouse

    PubMed Central

    Jang, In-Bae; Lee, Dae-Young; Yu, Jin; Park, Hong-Woo; Mo, Hwang-Sung; Park, Kee-Choon; Hyun, Dong-Yun; Lee, Eung-Ho; Kim, Kee-Hong; Oh, Chang-Sik

    2015-01-01

    Background Ginseng is a semishade perennial plant cultivated in sloping, sun-shaded areas in Korea. Recently, owing to air-environmental stress and various fungal diseases, greenhouse cultivation has been suggested as an alternative. However, the optimal light transmission rate (LTR) in the greenhouse has not been established. Methods The effect of LTR on photosynthesis rate, growth, and ginsenoside content of ginseng was examined by growing ginseng at the greenhouse under 6%, 9%, 13%, and 17% of LTR. Results The light-saturated net photosynthesis rate (Asat) and stomatal conductance (gs) of ginseng increased until the LTR reached 17% in the early stage of growth, whereas they dropped sharply owing to excessive leaf chlorosis at 17% LTR during the hottest summer period in August. Overall, 6–17% of LTR had no effect on the aerial part of plant length or diameter, whereas 17% and 13% of LRT induced the largest leaf area and the highest root weight, respectively. The total ginsenoside content of the ginseng leaves increased as the LTR increased, and the overall content of protopanaxatriol line ginsenosides was higher than that of protopanaxadiol line ginsenosides. The ginsenoside content of the ginseng roots also increased as the LTR increased, and the total ginsenoside content of ginseng grown at 17% LTR increased by 49.7% and 68.3% more than the ginseng grown at 6% LTR in August and final harvest, respectively. Conclusion These results indicate that 13–17% of LTR should be recommended for greenhouse cultivation of ginseng. PMID:26869827

  15. Photosynthesis rates, growth, and ginsenoside contents of 2-yr-old Panax ginseng grown at different light transmission rates in a greenhouse.

    PubMed

    Jang, In-Bae; Lee, Dae-Young; Yu, Jin; Park, Hong-Woo; Mo, Hwang-Sung; Park, Kee-Choon; Hyun, Dong-Yun; Lee, Eung-Ho; Kim, Kee-Hong; Oh, Chang-Sik

    2015-10-01

    Ginseng is a semishade perennial plant cultivated in sloping, sun-shaded areas in Korea. Recently, owing to air-environmental stress and various fungal diseases, greenhouse cultivation has been suggested as an alternative. However, the optimal light transmission rate (LTR) in the greenhouse has not been established. The effect of LTR on photosynthesis rate, growth, and ginsenoside content of ginseng was examined by growing ginseng at the greenhouse under 6%, 9%, 13%, and 17% of LTR. The light-saturated net photosynthesis rate (A sat) and stomatal conductance (g s) of ginseng increased until the LTR reached 17% in the early stage of growth, whereas they dropped sharply owing to excessive leaf chlorosis at 17% LTR during the hottest summer period in August. Overall, 6-17% of LTR had no effect on the aerial part of plant length or diameter, whereas 17% and 13% of LRT induced the largest leaf area and the highest root weight, respectively. The total ginsenoside content of the ginseng leaves increased as the LTR increased, and the overall content of protopanaxatriol line ginsenosides was higher than that of protopanaxadiol line ginsenosides. The ginsenoside content of the ginseng roots also increased as the LTR increased, and the total ginsenoside content of ginseng grown at 17% LTR increased by 49.7% and 68.3% more than the ginseng grown at 6% LTR in August and final harvest, respectively. These results indicate that 13-17% of LTR should be recommended for greenhouse cultivation of ginseng.

  16. Coastal vegetation invasion increases greenhouse gas emission from wetland soils but also increases soil carbon accumulation.

    PubMed

    Chen, Yaping; Chen, Guangcheng; Ye, Yong

    2015-09-01

    Soil properties and soil-atmosphere fluxes of CO2, CH4 and N2O from four coastal wetlands were studied throughout the year, namely, native Kandelia obovata mangrove forest vs. exotic Sonneratia apetala mangrove forest, and native Cyperus malaccensis salt marsh vs. exotic Spartina alterniflora salt marsh. Soils of the four wetlands were all net sources of greenhouse gases while Sonneratia forest contributed the most with a total soil-atmosphere CO2-equivalent flux of 137.27 mg CO2 m(-2) h(-1), which is 69.23%, 99.75% and 44.56% higher than that of Kandelia, Cyperus and Spartina, respectively. The high underground biomass and distinctive root structure of Sonneratia might be responsible for its high greenhouse gas emission from the soil. Soils in Spartina marsh emitted the second largest amount of total greenhouse gases but it ranked first in emitting trace greenhouse gases. Annual average CH4 and N2O fluxes from Spartina soil were 13.77 and 1.14 μmol m(-2) h(-1), respectively, which are 2.08 and 1.46 times that of Kandelia, 1.03 and 1.15 times of Sonneratia, and 1.74 and 1.02 times of Cyperus, respectively. Spartina has longer growing season and higher productivity than native marshes which might increase greenhouse gas emission in cold seasons. Exotic wetland soils had higher carbon stock as compared to their respective native counterparts but their carbon stocks were offset by a larger proportion because of their higher greenhouse gas emissions. Annual total soil-atmosphere fluxes of greenhouse gases reduced soil carbon burial benefits by 8.1%, 9.5%, 6.4% and 7.2% for Kandelia, Sonneratia, Cyperus and Spartina, respectively, which narrowed down the gaps in net soil carbon stock between native and exotic wetlands. The results indicated that the invasion of exotic wetland plants might convert local coastal soils into a considerable atmospheric source of greenhouse gases although they at the same time increase soil carbon accumulation.

  17. Water level, vegetation composition and plant productivity explain greenhouse gas fluxes in temperate cutover fens after inundation

    NASA Astrophysics Data System (ADS)

    Minke, M.; Augustin, J.; Burlo, A.; Yarmashuk, T.; Chuvashova, H.; Thiele, A.; Freibauer, A.; Tikhonov, V.; Hoffmann, M.

    2015-10-01

    Rewetting of temperate continental cutover peatlands generally implies the creation of flooded areas, which are - dependent on water depth - colonized by helophytes such as Eriophorum angustifolium, Carex spp., Typha latifolia or Phragmites australis. Reeds of Typha and Phragmites are reported to be large sources of methane, but data on net CO2 uptake are contradictory for Typha and rare for Phragmites. This paper describes the effect of vegetation, water level and nutrient conditions on greenhouse gas (GHG) emissions for representative vegetation types along water level gradients at two rewetted cutover fens (mesotrophic and eutrophic) in Belarus. Greenhouse emissions were measured with manual chambers in weekly to few - weekly intervals over a two years period and interpolated by modelling. All sites had negligible nitrous oxide exchange rates. Most sites were carbon sinks and small GHG sources. Methane emissions were generally associated with net ecosystem CO2 uptake. Small sedges were minor methane emitters and net CO2 sinks, while Phragmites australis sites released large amounts of methane and sequestered very much CO2. Variability of both fluxes increased with site productivity. Floating mats composed of Carex tussocks and Typha latifolia were a source for both methane and CO2. We conclude that shallow, stable flooding is a better measure to arrive at low GHG emissions than deep flooding, and that the risk of high GHG emissions consequent on rewetting is larger for eutrophic than for mesotrophic peatlands.

  18. Thermal and wind-driven water motions in vegetated waters and their role in greenhouse gas fluxes

    NASA Astrophysics Data System (ADS)

    Poindexter, C.; Variano, E. A.

    2016-12-01

    The relative importance of different methane transport pathways in wetlands can impact total wetland methane fluxes. The transport of methane and other gases through the water column is affected by a variety of forces. We investigate the role of wind- and thermally-driven water motions in greenhouse gas fluxes in a freshwater marsh and a rice field using in situ velocity measurements in combination with gas transfer velocity models. We measure velocity using an Acoustic Doppler velocimeter, correcting for instrument generated velocities, and a Volumetric Particle Imager. These measurements indicate the presence of wind-driven motions in the wetland water column located below a dense 3-m emergent vegetation canopy. In the rice field's water column, velocity data suggest the occurrence of thermal convection. Results from these in-situ velocity measurements correspond with the non-negligible gas transfer velocities we predict via semi-empirical models. This underscores the importance of hydrodynamics to greenhouse gas fluxes even in shallow, vegetated inland waters.

  19. Visual marker and Agrobacterium-delivered recombinase enable the manipulation of the plastid genome in greenhouse-grown tobacco plants.

    PubMed

    Tungsuchat-Huang, Tarinee; Maliga, Pal

    2012-05-01

    Successful manipulation of the plastid genome (ptDNA) has been carried out so far only in tissue-culture cells, a limitation that prevents plastid transformation being applied in major agronomic crops. Our objective is to develop a tissue-culture independent protocol that enables manipulation of plastid genomes directly in plants to yield genetically stable seed progeny. We report that in planta excision of a plastid aurea bar gene (bar(au) ) is detectable in greenhouse-grown plants by restoration of the green pigmentation in tobacco leaves. The P1 phage Cre or PhiC31 phage Int site-specific recombinase was delivered on the Agrobacterium T-DNA injected at the axillary bud site, resulting in the excision of the target-site flanked marker gene. Differentiation of new apical meristems was forced by decapitating the plants above the injection site. The new shoot apex that differentiated at the injection site contained bar(au)-free plastids in 30-40% of the injected plants, of which 7% transmitted the bar(au)-free plastids to the seed progeny. The success of obtaining seed with bar(au)-free plastids depended on repeatedly forcing shoot development from axillary buds, a process that was guided by the size and position of green sectors in the leaves. The success of in planta plastid marker excision proved that manipulation of the plastid genomes is feasible within an intact plant. Extension of the protocol to in planta plastid transformation depends on the development of new protocols for the delivery of transforming DNA encoding visual markers. © 2012 The Authors. The Plant Journal © 2012 Blackwell Publishing Ltd.

  20. Water level, vegetation composition, and plant productivity explain greenhouse gas fluxes in temperate cutover fens after inundation

    NASA Astrophysics Data System (ADS)

    Minke, Merten; Augustin, Jürgen; Burlo, Andrei; Yarmashuk, Tatsiana; Chuvashova, Hanna; Thiele, Annett; Freibauer, Annette; Tikhonov, Vitalij; Hoffmann, Mathias

    2016-07-01

    Peat extraction leaves a land surface with a strong relief of deep cutover areas and higher ridges. Rewetting inundates the deep parts, while less deeply extracted zones remain at or above the water level. In temperate fens the flooded areas are colonized by helophytes such as Eriophorum angustifolium, Carex spp., Typha latifolia or Phragmites australis dependent on water depth. Reeds of Typha and Phragmites are reported as large sources of methane, but data on net CO2 uptake are contradictory for Typha and rare for Phragmites. Here, we analyze the effect of vegetation, water level and nutrient conditions on greenhouse gas (GHG) emissions for representative vegetation types along water level gradients at two rewetted cutover fens (mesotrophic and eutrophic) in Belarus. Greenhouse gas emissions were measured campaign-wise with manual chambers every 2 to 4 weeks for 2 years and interpolated by modelling. All sites had negligible nitrous oxide exchange rates. Most sites were carbon sinks and small GHG sources. Methane emissions generally increased with net ecosystem CO2 uptake. Mesotrophic small sedge reeds with water table around the land surface were small GHG sources in the range of 2.3 to 4.2 t CO2 eq. ha-1 yr-1. Eutrophic tall sedge - Typha latifolia reeds on newly formed floating mats were substantial net GHG emitters in the range of 25.1 to 39.1 t CO2 eq. ha-1 yr. They represent transient vegetation stages. Phragmites reeds ranged between -1.7 to 4.2 t CO2 eq. ha-1 yr-1 with an overall mean GHG emission of 1.3 t CO2 eq. ha-1 yr-1. The annual CO2 balance was best explained by vegetation biomass, which includes the role of vegetation composition and species. Methane emissions were obviously driven by biological activity of vegetation and soil organisms. Shallow flooding of cutover temperate fens is a suitable measure to arrive at low GHG emissions. Phragmites australis establishment should be promoted in deeper flooded areas and will lead to moderate, but

  1. Greenhouse gas emission response to global change may be limited by vegetation community shifts

    EPA Science Inventory

    Coastal marshes experience a confluence of global changes including climate change, sea level rise, exotic species invasion, and eutrophication. These changes are likely to exert new abiotic stressors and affect interspecific interactions that influence vegetation community stru...

  2. Greenhouse gas emission response to global change may be limited by vegetation community shifts

    EPA Science Inventory

    Coastal marshes experience a confluence of global changes including climate change, sea level rise, exotic species invasion, and eutrophication. These changes are likely to exert new abiotic stressors and affect interspecific interactions that influence vegetation community stru...

  3. Vegetation dynamics and plant CO2 responses as positive feedbacks in a greenhouse world

    NASA Astrophysics Data System (ADS)

    O'ishi, Ryouta; Abe-Ouchi, Ayako; Prentice, I. Colin; Sitch, Stephen

    2009-06-01

    An atmosphere-ocean-vegetation coupled model is used to quantify the biogeophysical feedback that emerges as vegetation adjusts dynamically to a quadrupling of atmospheric CO2. This feedback amplifies global warming by 13%. About half of it is due to climatically induced expansion of boreal forest into tundra, reinforced by reductions in snow and sea ice cover. The other half represents a global climatic effect of increased vegetative cover (an indirect consequence of plant physiological responses to CO2) in the semi-arid subtropics. Enhanced absorption of shortwave radiation in these regions produces a net surface warming, which the atmosphere communicates poleward. The greatest vegetation-induced warming is co-located with large, vulnerable carbon stores in the north. These lose carbon, so that in the long term, the biospheric response to CO2 and climate change becomes dominated by positive feedbacks that overwhelm the effect of CO2 fertilization on terrestrial carbon stocks.

  4. Uptake and distribution of minerals and heavy metals in commonly grown leafy vegetable species irrigated with sewage water.

    PubMed

    Anwar, Sumera; Nawaz, Muhammad Farrakh; Gul, Sadaf; Rizwan, Muhammad; Ali, Shafaqat; Kareem, Arshaad

    2016-09-01

    Heavy metal uptake and accumulation behavior in dietary vegetables irrigated with sewage waters is an important issue worldwide. The main objective of this study was to examine and compare the physiological and growth responses of leafy vegetables irrigated with sewage water. A pot experiment was conducted in a wire house with three leafy vegetables, coriander (Coriandrum sativum), mint (Mentha arvensis), and fenugreek (Trigonella foenum), grown under ambient conditions. Plants were irrigated with different concentrations, 0, 50 (T 1), and 100 % (T 2), of sewage water. After harvesting, morphological and physiological parameters of plants were measured. Heavy metal (Cd, Cu, Pb, and Zn) concentrations in the sewage water were found much higher than safer limits. The results revealed that the highest plant biomass and lowest metal contents were observed in control treatments in all studied vegetables. The biomass of all the vegetables were negatively affected when irrigated with sewage water. In T 2, coriander accumulated maximum Cd (μg g(-1) DW) in shoots (4.97) as compared to other vegetables. The maximum Pb and Cu concentrations were accumulated in mint roots (44 and 3.9, respectively) as compared to coriander and fenugreek. Zinc was accumulated in the sequence of leaves > roots > shoots under polluted water irrigation. The concentrations of potassium increased in leaves, shoots, and roots in all vegetables, while phosphorous concentrations varied with species and plant parts with increasing sewage water concentration. It was found that the leafy vegetables grown with sewage water irrigation may cause severe human health problems.

  5. Biomass and vegetative characteristics of sawgrass grown in a tilting flume as part of a study of vegetative resistance to flow

    USGS Publications Warehouse

    Rybicki, N.B.; Reel, J.T.; Ruhl, H.; Gammon, P.T.; Carter, Virginia; Lee, J.K.

    1999-01-01

    The U.S. Geological Survey is studying vegetative resistance to flow in the south Florida Everglades as part of a multidisciplinary effort to restore the South Florida Ecosystem. In order to test the flow resistance of sawgrass, one of the dominant species in the Everglades, uniform, dense stands of sawgrass were grown in a tilting flume at Stennis Space Center, Mississippi. Depth of water in the flume was controlled by adding or removing metal plates at the downstream end of the flume. A series of experiments were conducted at various flow depths, and the velocity, flow depth, and water-surface slope were measured. During each set of experiments, the sawgrass was sampled in layers from the sediment water interface for vegetative characteristics, biomass, and leaf area index. The results of the vegetation sampling are summarized in a series of tables.

  6. Variation in Factors Regulating Net Greenhouse Gas Exchange Across Different Vegetation Types at Cape Bounty, Melville Island, Nunavut

    NASA Astrophysics Data System (ADS)

    Scott, N. A.; Blaser, A.; Buckley, E.; Humphreys, E.; Treitz, P.

    2015-12-01

    Global-scale climate simulations predict significant changes both in temperature and moisture regimes in the high Arctic. This could lead to changes in vegetation community distribution, as vegetation communities are distributed along moisture gradients often determined by snowfall patterns across the landscape. Furthermore, changes in soil moisture and temperature could alter fluxes of greenhouse gases such as carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O), and the impacts of changes in these controlling factors could vary by vegetation type.We measured both spatial and temporal variation in CO2 fluxes using combinations of eddy covariance, auto-chamber, and static chamber techniques at the Cape Bounty Arctic Watershed Observatory (CBAWO). Measurements were performed in three major plant community types: polar semi-desert (PSD), mid-moisture tundra (MM) and wet sedge meadow (WS). Based on our auto-chamber data collected in all vegetation types, ecosystem respiration (ER) related positively to air temperature, and correlated more strongly with air temperature than soil temperature. Modeled ER based on eddy covariance data and air temperature over MM agreed well with measured ER in the same vegetation type. In the WS community, average net ecosystem exchange (NEE) in 2014 measured by static chambers differed in spectrally separable 'wet' and 'dry' sedge areas (-0.33 and 0.01 µmol m-2 s-1, respectively; p<0.001). Rates of ER also varied across this moisture gradient (p<0.05). Over the entire growing season and multiple years, NEE correlated poorly with air and soil temperature, suggesting that ER is not the dominant processes driving NEE. This can vary, however, over the growing season. In PSD communities measured in 2013, air temperature related positively to NEE early in the growing season, but not during the latter part of the season, when PAR (photosynthesis) became the key factor controlling NEE. Not surprisingly, NEE related strongly (0.93) to

  7. Effect of long-term application of treated sewage water on heavy metal accumulation in vegetables grown in northern India.

    PubMed

    Ghosh, Amlan Kr; Bhatt, M A; Agrawal, H P

    2012-01-01

    Use of industrial and wastewater for irrigation is on the rise in India and other developing countries because of scarcity of good-quality irrigation water. Wastewaters contain plant nutrients that favour crop growth but leave a burden of heavy metals which can enter the food chain and is a cause of great concern. The present study was undertaken on the long-term impact of irrigation with treated sewage water for growing vegetables and the potential health risk associated with consumption of such vegetable. Treated sewage water (TSW), groundwater (GW), soil and plant samples were collected from peri urban vegetable growing areas of Northern India (Varanasi) and analysed to assess the long-term effect of irrigation with TSW on Cd, Cr, Ni and Pb build-up in soils and its subsequent transfer into commonly grown vegetable crops. Results indicate that TSW was richer in essential plant nutrients but contained Cd, Cr and Ni in amounts well above the permissible limits for its use as irrigation water. Long-term application of TSW resulted in significant build-up of total and DTPA extractable Cd, Cr, Ni and Pb over GW irrigated sites. TSW also resulted in slight lowering in pH, increase in organic carbon (1.6 g kg(-1)) and cation exchange capacity (5.2 cmol kg(-1)). The tissue metal concentration and relative efficiency of transfer of heavy metals from soil to plant (transfer factor) for various groups of vegetables were worked out. Radish, turnip and spinach were grouped as hyper accumulator of heavy metals whereas brinjal and cauliflower accumulated less heavy metals. Health risk assessment by consumption of vegetables grown with TSW indicated that all the vegetables were safe for human consumption. However, significant accumulation of these heavy metals in soil and plant needs to be monitored.

  8. RNA-mediated gene silencing signals are not graft transmissible from the rootstock to the scion in greenhouse-grown apple plants Malus sp.

    PubMed

    Flachowsky, Henryk; Tränkner, Conny; Szankowski, Iris; Waidmann, Sascha; Hanke, Magda-Viola; Treutter, Dieter; Fischer, Thilo C

    2012-01-01

    RNA silencing describes the sequence specific degradation of RNA targets. Silencing is a non-cell autonomous event that is graft transmissible in different plant species. The present study is the first report on systemic acquired dsRNA-mediated gene silencing of transgenic and endogenous gene sequences in a woody plant like apple. Transgenic apple plants overexpressing a hairpin gene construct of the gusA reporter gene were produced. These plants were used as rootstocks and grafted with scions of the gusA overexpressing transgenic apple clone T355. After grafting, we observed a reduction of the gusA gene expression in T355 scions in vitro, but not in T355 scions grown in the greenhouse. Similar results were obtained after silencing of the endogenous Mdans gene in apple that is responsible for anthocyanin biosynthesis. Subsequently, we performed grafting experiments with Mdans silenced rootstocks and red leaf scions of TNR31-35 in order to evaluate graft transmitted silencing of the endogenous Mdans. The results obtained suggested a graft transmission of silencing signals in in vitro shoots. In contrast, no graft transmission of dsRNA-mediated gene silencing signals was detectable in greenhouse-grown plants and in plants grown in an insect protection tent.

  9. RNA-Mediated Gene Silencing Signals Are Not Graft Transmissible from the Rootstock to the Scion in Greenhouse-Grown Apple Plants Malus sp

    PubMed Central

    Flachowsky, Henryk; Tränkner, Conny; Szankowski, Iris; Waidmann, Sascha; Hanke, Magda-Viola; Treutter, Dieter; Fischer, Thilo C.

    2012-01-01

    RNA silencing describes the sequence specific degradation of RNA targets. Silencing is a non-cell autonomous event that is graft transmissible in different plant species. The present study is the first report on systemic acquired dsRNA-mediated gene silencing of transgenic and endogenous gene sequences in a woody plant like apple. Transgenic apple plants overexpressing a hairpin gene construct of the gusA reporter gene were produced. These plants were used as rootstocks and grafted with scions of the gusA overexpressing transgenic apple clone T355. After grafting, we observed a reduction of the gusA gene expression in T355 scions in vitro, but not in T355 scions grown in the greenhouse. Similar results were obtained after silencing of the endogenous Mdans gene in apple that is responsible for anthocyanin biosynthesis. Subsequently, we performed grafting experiments with Mdans silenced rootstocks and red leaf scions of TNR31-35 in order to evaluate graft transmitted silencing of the endogenous Mdans. The results obtained suggested a graft transmission of silencing signals in in vitro shoots. In contrast, no graft transmission of dsRNA-mediated gene silencing signals was detectable in greenhouse-grown plants and in plants grown in an insect protection tent. PMID:22949844

  10. Quantifying the Negative Feedback of Vegetation to Greenhouse Warming: A Modeling Approach

    NASA Technical Reports Server (NTRS)

    Bounous, L.; Hall, F. G.; Sellers, P. J.; Kumar, A.; Collatz, G. J.; Tucker, C. J.; Imhoff, M. L.

    2010-01-01

    Several climate models indicate that in a 2 x CO2 environment, temperature and precipitation would increase and runoff would increase faster than precipitation. These models, however, did not allow the vegetation to increase its leaf density as a response to the physiological effects of increased CO2 and consequent changes in climate. Other assessments included these interactions but did not account for the vegetation down-regulation to reduce plant's photosynthetic activity and as such resulted in a weak vegetation negative response. When we combine these interactions in climate simulations with 2 x CO2, the associated increase in precipitation contributes primarily to increase evapotranspiration rather than surface runoff, consistent with observations, and results in an additional cooling effect not fully accounted for in previous simulations with elevated CO2. By accelerating the water cycle, this feedback slows but does not alleviate the projected warming, reducing the land surface warming by 0.6 C. Compared to previous studies, these results imply that long term negative feedback from CO2-induced increases in vegetation density could reduce temperature following a stabilization of CO2 concentration.

  11. A Monitoring System for Vegetable Greenhouses based on a Wireless Sensor Network

    PubMed Central

    Li, Xiu-hong; Cheng, Xiao; Yan, Ke; Gong, Peng

    2010-01-01

    A wireless sensor network-based automatic monitoring system is designed for monitoring the life conditions of greenhouse vegetatables. The complete system architecture includes a group of sensor nodes, a base station, and an internet data center. For the design of wireless sensor node, the JN5139 micro-processor is adopted as the core component and the Zigbee protocol is used for wireless communication between nodes. With an ARM7 microprocessor and embedded ZKOS operating system, a proprietary gateway node is developed to achieve data influx, screen display, system configuration and GPRS based remote data forwarding. Through a Client/Server mode the management software for remote data center achieves real-time data distribution and time-series analysis. Besides, a GSM-short-message-based interface is developed for sending real-time environmental measurements, and for alarming when a measurement is beyond some pre-defined threshold. The whole system has been tested for over one year and satisfactory results have been observed, which indicate that this system is very useful for greenhouse environment monitoring. PMID:22163391

  12. Evaluation of corn plant as potential banker plant for supporting predatory gall Midge, Feltiella acarisuga (Diptera: Cecidomyiidae) against Tetranychus urticae (Acari: Tetranychidae) in greenhouse vegetable production

    USDA-ARS?s Scientific Manuscript database

    The twospotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae), is one of the most important and highly polyphagous pests of vegetables and other crops worldwide. In this study, several experiments were conducted under laboratory and greenhouse conditions to evaluate whether corn plant ...

  13. Study on the idity fuzzy neural network controller based on improved genetic algorithm of intelligent temperature control system in vegetable greenhouse

    NASA Astrophysics Data System (ADS)

    Zhang, Su; Yuan, Hongbo; Zhou, Yuhong; Wang, Nan

    2009-07-01

    In order to create the environment that the suitable crop grows, direct against the characteristic of the system of the greenhouse. The aim of the research was to study the intelligent temperature control system in vegetable greenhouse. Based on computer automatic control ,a kind of intelligent temperature control system in vegetable greenhouse was designed. The design thought of systematic hardwares such as temperature collection system, temperature display, control system, heater control circuit in the heater were expounded in detail The control algorithm of the system was improved and system simulation was made by using MATLAB finally. The control algorithm of the system was improved by a new fuzzy neural network controller. The stimulation curve showed that the system had better controlling and tracking performances ,higher accuracy of controlling the temperature. And this system and host epigyny computer could constitute the secondary computer control system which was favorable for realizing the centralized management of the production.

  14. [N2O emission from an intensively managed greenhouse vegetable field in Nanjing suburb, Jiangsu Province of East China].

    PubMed

    Jia, Jun-Xiang; Zhang, Man; Xiong, Zheng-Qin; Li, Ye

    2012-03-01

    By using static opaque chamber and gas chromatography, this paper studied the dynamic changes of N2O fluxes and their relationships with soil temperature, soil moisture content, and soil nitrate and ammonium contents in an intensively managed greenhouse celery-Tung choy-Bok choy-amaranth rotation field and in a bare fallow land in Nanjing suburb. The cumulative N2O emission from the rotation vegetable field was as high as 137.2 kg N x hm(-2), being significantly higher than that from the bare fallow land (29.2 kg N x hm(-2)), and the N2O-N emission factor of the rotation vegetable field ecosystem was up to 4.6%. In the rotation field, the planting of Tung choy had the greatest contribution to the annual cumulative N2O emission, occupying 53.5% of the total, followed by the planting of Bok choy (31.9%), celery field (4.5%), and amaranth (4.8%). The N2O flux of the rotation field had significant positive correlation with soil temperature, the Q10 being 2.80, but no significant correlations with soil moisture content and soil nitrate and ammonium contents.

  15. The Early Paleogene Greenhouse and PCO2: A Look at the Role and Response of Vegetation

    NASA Astrophysics Data System (ADS)

    Shellito, L. J.; Sloan, L. C.

    2003-12-01

    This study uses the NCAR Community Climate Model (v.3.6.6) (CCM) and dynamic vegetation global model (DVGM) to assess potential responses of Early Paleogene (50-60 Ma) flora to changes in pCO2, and to examine the role that this flora may have had in supporting the warm climate of this time period. We compare the vegetation in model output with the invariable Early Eocene land cover used to drive previous global climate model experiments. The invariable land cover was derived from Paleogene fossil flora and may produce inconsistencies between climate and vegetation in a model, especially in lower pCO2 scenarios, where high latitudes become too cool to support Eocene fossil flora. We drive the DVGM with climate data generated from two experiments with the CCM. In one experiment, pCO2 is set at 560 ppm, and the other, at 1120 ppm. We find that the higher pCO2 experiment allows the plant functional types which favor warmer climates to increase their latitudinal range, and thus become more consistent with proxy interpretations of the distribution of flora during this time period.

  16. Accumulation, sources and health risks of trace metals in elevated geochemical background soils used for greenhouse vegetable production in southwestern China.

    PubMed

    Zhang, Haidong; Huang, Biao; Dong, Linlin; Hu, Wenyou; Akhtar, Mohammad Saleem; Qu, Mingkai

    2017-03-01

    Greenhouse vegetable cultivation with substantive manure and fertilizer input on soils with an elevated geochemical background can accumulate trace metals in soils and plants leading to human health risks. Studies on trace metal accumulation over a land use shift duration in an elevated geochemical background scenario are lacking. Accumulation characteristics of seven trace metals in greenhouse soil and edible plants were evaluated along with an assessment of the health risk to the consumers. A total of 118 greenhouse surface soils (0-20cm) and 30 vegetables were collected from Kunming City, Yunnan Province, southwestern China, and analyzed for total Cd, Pb, Cu, Zn, As, Hg, and Cr content by ICP-MS and AFS. The trace metals were ordered Cu>Cd>Hg>Zn>Pb>As>Cr in greenhouse soils accumulation level, and the geo-accumulation index suggested the soil more severely polluted with Cd, Cu, Hg and Zn. The greenhouse and open-field soils had significant difference in Cd, Cr and Zn. The duration of shift from paddy to greenhouse land-use significantly influenced trace metal accumulation with a dramatic change during five to ten year greenhouse land-use, and continuous increase of Cd and Hg. A spatial pattern from north to south for Cd and Hg and a zonal pattern for Cu and Zn were found. An anthropogenic source primarily caused trace metal accumulation, where the principal component analysis/multiple linear regression indicated a contribution 61.2%. While the assessment showed no potential risk for children and adults, the hazard health risks index was greater than one for adolescents. The extended duration of land use as greenhouses caused the trace metal accumulation, rotation in land use should be promoted to reduce the health risks.

  17. Bioconcentration of polycyclic aromatic hydrocarbons in vegetables grown in an industrial area.

    PubMed

    Kipopoulou, A M; Manoli, E; Samara, C

    1999-09-01

    The polycyclic aromatic hydrocarbon (PAH) content was determined in the inner tissue of various vegetable species and their growing environment (soil and atmosphere) in the greater industrial area of Thessaloniki, northern Greece. The lower molecular weight compounds dominated in both vegetable leaves and roots. Statistical analysis of variance showed that species and season are the factors that significantly affect PAH concentrations in inner vegetable tissue and soil, respectively. Principal component analysis indicated that the mixture of PAHs in inner vegetable tissue was very similar to that in air vapour thus suggesting gaseous deposition as the principal pathway for the accumulation of PAHs. Soil-to-vegetation and air-to-vegetation bioconcentration factors were calculated and their relationships with PAHs' physicochemical properties were investigated. Solubility and the octanol-water partition coefficient, as well as vapour pressure and the octanol-air partition coefficient were proved to be good predictors for the accumulation of PAHs in inner root and leaf tissue, respectively.

  18. Escherichia coli Contamination of Vegetables Grown in Soils Fertilized with Noncomposted Bovine Manure: Garden-Scale Studies

    PubMed Central

    Ingham, Steven C.; Losinski, Jill A.; Andrews, Matthew P.; Breuer, Jane E.; Breuer, Jeffry R.; Wood, Timothy M.; Wright, Thomas H.

    2004-01-01

    In this study we tested the validity of the National Organic Program (NOP) requirement for a ≥120-day interval between application of noncomposted manure and harvesting of vegetables grown in manure-fertilized soil. Noncomposted bovine manure was applied to 9.3-m2 plots at three Wisconsin sites (loamy sand, silt loam, and silty clay loam) prior to spring and summer planting of carrots, radishes, and lettuce. Soil and washed (30 s under running tap water) vegetables were analyzed for indigenous Escherichia coli. Within 90 days, the level of E. coli in manure-fertilized soil generally decreased by about 3 log CFU/g from initial levels of 4.2 to 4.4 log CFU/g. Low levels of E. coli generally persisted in manure-fertilized soil for more than 100 days and were detected in enriched soil from all three sites 132 to 168 days after manure application. For carrots and lettuce, at least one enrichment-negative sample was obtained ≤100 days after manure application for 63 and 88% of the treatments, respectively. The current ≥120-day limit provided an even greater likelihood of not detecting E. coli on carrots (≥1 enrichment-negative result for 100% of the treatments). The rapid maturation of radishes prevented conclusive evaluation of a 100- or 120-day application-to-harvest interval. The absolute absence of E. coli from vegetables harvested from manure-fertilized Wisconsin soils may not be ensured solely by adherence to the NOP ≥120-day limit. Unless pathogens are far better at colonizing vegetables than indigenous E. coli strains are, it appears that the risk of contamination for vegetables grown in Wisconsin soils would be elevated only slightly by reducing the NOP requirement to ≥100 days. PMID:15528501

  19. Plant density and N fertilizer rate on yield and nutrient content of onion developed from greenhouse grown transplants

    USDA-ARS?s Scientific Manuscript database

    Onions (Allium cepa L.) can be established from seed or transplants. The latter planting material can be dormant or actively growing when transplanted to the field. Onion transplants can be produced in a greenhouse, but additional information is needed regarding the cultural requirements for these...

  20. Plant response of onion cultivars developed from greenhouse-grown transplants to plant density and fertilizer rate

    USDA-ARS?s Scientific Manuscript database

    Onions (Allium cepa L.) can be established from seed or transplants. The latter planting material can be dormant or actively growing when transplanted to the field. Onion transplants can be produced in a greenhouse, but there are gaps in the knowledge of the cultural requirements for these plants ...

  1. Assessing risk to human health from tropical leafy vegetables grown on contaminated urban soils.

    PubMed

    Nabulo, G; Young, S D; Black, C R

    2010-10-15

    Fifteen tropical leafy vegetable types were sampled from farmers' gardens situated on nine contaminated sites used to grow vegetables for commercial or subsistence consumption in and around Kampala City, Uganda. Trace metal concentrations in soils were highly variable and originated from irrigation with wastewater, effluent discharge from industry and dumping of solid waste. Metal concentrations in the edible shoots of vegetables also differed greatly between, and within, sites. Gynandropsis gynandra consistently accumulated the highest Cd, Pb and Cu concentrations, while Amaranthus dubius accumulated the highest Zn concentration. Cadmium uptake from soils with contrasting sources and severity of contamination was consistently lowest in Cucurbita maxima and Vigna unguiculata, suggesting these species were most able to restrict Cd uptake from contaminated soil. Concentrations of Pb and Cr were consistently greater in unwashed, than in washed, vegetables, in marked contrast to Cd, Ni and Zn. The risk to human health, expressed as a 'hazard quotient' (HQ(M)), was generally greatest for Cd, followed successively by Pb, Zn, Ni and Cu. Nevertheless, it was apparent that urban cultivation of leafy vegetables could be safely pursued on most sites, subject to site-specific assessment of soil metal burden, judicious choice of vegetable types and adoption of washing in clean water prior to cooking.

  2. Salicylic acid in soups prepared from organically and non-organically grown vegetables.

    PubMed

    Baxter, G J; Graham, A B; Lawrence, J R; Wiles, D; Paterson, J R

    2001-12-01

    Salicylic acid is a chemical signal in plants infected by pathogens and it is responsible for the anti-inflammatory action of aspirin. Patients who take aspirin have a reduced risk of developing atherosclerosis and colorectal cancer, both of these pathologies having an inflammatory component. Dietary salicylic acid may help to prevent these conditions. We wondered if foods made from organically-reared plants might have a higher content of salicylic acid than those made from non-organic plants, since the latter are more likely to be protected from infection by the application of pesticides. To determine if organic vegetable soups have a higher salicylic acid content than non-organic vegetable soups. The contents of salicylic acid in organic and non-organic vegetable soups purchased from supermarkets were determined. Salicylic acid was identified by varying the chromatographic conditions and comparing the retention times of the unknown substance in the extracts with salicylic acid; by treating extracts of the soups with salicylate hydroxylase; and by using GCMS. Salicylic acid was determined by using HPLC with electrochemical detection. Salicylic acid was present in all of the organic and most of the non-organic vegetable soups. The median contents of salicylic acid in the organic and non-organic vegetable soups were 117 (range, 8-1040) ng x g(-1) and 20 (range, 0-248) ng x g(-1) respectively. The organic soups had a significantly higher content of salicylic acid (p=0.0032 Mann Whitney U test), with a median difference of 59 ng g(-1) (95 % confidence interval, 18-117ng x g(-1)). Organic vegetable soups contained more salicylic acid than non-organic ones, suggesting that the vegetables and plants used to prepare them contained greater amounts of the phenolic acid than the corresponding non-organic ingredients. Consumption of organic foods may result in a greater intake of salicylic acid.

  3. Vegetation, soil property and climatic controls over greenhouse gas fluxes in a blanket peatland hosting a wind farm

    NASA Astrophysics Data System (ADS)

    Armstrong, Alona; Waldron, Susan; Ostle, Nick; Whitaker, Jeanette

    2013-04-01

    Peatlands are important carbon (C) stores, with boreal and subarctic peatlands containing 15-30 % of the world soil carbon stock (Limpens et al., 2008). Research has demonstrated that greenhouse gas (GHG) fluxes in peatlands are influenced by vegetation, soil property and climatic variables, including plant functional type (PFT), water table height and temperature. In this paper we present data from Black Law Wind Farm, Scotland, where we examined the effect of a predicted wind turbine-induced microclimatic gradient and PFT on carbon dioxide (CO2) and methane (CH4) fluxes. Moreover, we determined the role of vegetation, soil property and climatic variables as predictors of the variation in CO2 and CH4 emissions. We measured CO2 and CH4 at 48 plots within Black Law Wind Farm at monthly intervals from May 2011 to April 2012. Four sampling sites were located along a predicted wind turbine-induced microclimatic gradient. At each site four blocks were established, each with plots in areas dominated by mosses, sedges and shrubs. Plant biomass and PFT (vegetation factors); soil moisture, water table height, peat depth, C content, nitrogen (N) content and C:N (soil properties); and soil temperature and photosynthetically active radiation (PAR) (climatic variables) were measured. Analysis of variance (ANOVA) models based on the microclimatic gradient site, PFT and season when measurements were made explained 58 %, 44 % and 49 % of the variation in ecosystem respiration, photosynthesis and CH4, respectively. Site, PFT, season and their interactions were all significant for respiration and photosynthesis (with the exception of the PFT*site interaction) but for CH4 only the main effects were significant. Parsimonious ANOVA models using the biotic, soil property and climatic explanatory data explained 62 %, 55 % and 49 % of the variation in respiration, photosynthesis and CH4, respectively. Published studies (Baidya Roy and Traiteur 2010; Zhou et al., 2012) and preliminary

  4. To What Extent Can Vegetation Mitigate Greenhouse Warming? A Modeling Approach

    NASA Technical Reports Server (NTRS)

    Bounoua, L.; Hall, F.G.; Collatz, G.J.; Tucker, C.J.; Sellers, P.J.; Kumar, A.

    2008-01-01

    Climate models participating in the IPCC Fourth Assessment Report indicate that under a 2xCO2 environment, runoff would increase faster than precipitation overland. However, observations over large U.S watersheds indicate otherwise. This inconsistency suggests that there may be important feedbacks between climate and land surface unaccounted for in the present generation of models. We postulate that the increase in precipitation associated with the increase in CO2 is also increasing vegetation density, which may already be feeding back onto climate. Including this feedback in a climate model simulation resulted in precipitation and runoff trends consistent with observations and reduced the warming by 0.6OC overland. This unaccounted for missing water may be linked to about 10% of the missing land carbon sink. A recent compilation of outputs from 19 coupled atmosphere-ocean general circulation models used in the IPCC Fourth Assessment Report (AR4) shows projected increases in air temperature, precipitation and river discharge for 24 major rivers in the world in response to doubling CO2 by the end of the century (1). The ensemble mean from these models also indicates that, compared to their respective baselines overland, the global mean of the runoff change would increase faster (8.9% per year) than that of the precipitation (5% per year). We analyze century-scale observed annual runoff time-series (1901-2002) over 9 hydrological units covering large regions of the Eastern United States (Fig.1) compiled by the United States Geological Survey (USGS)(2). These regions were selected because they are the most forested; the least water-limited and are not under extensive irrigation. We compare these time-series to similar time-series of observed annual precipitation anomalies spanning the period 1900-1995 (3). Both time-series exhibit a positive longterm trend (Fig. 2); however, in contrast to the analysis of (I), these historic data records show that the rate of

  5. Toxicological assessment of heavy metals accumulated in vegetables and fruits grown in Ginfel river near Sheba Tannery, Tigray, Northern Ethiopia.

    PubMed

    Gebrekidan, Abraha; Weldegebriel, Yirgaalem; Hadera, Amanual; Van der Bruggen, Bart

    2013-09-01

    The accumulation of heavy metals in vegetables resulting from irrigation with contaminated water obtained from industrial effluents may create a potential public health risk. We quantified the concentration of heavy metals (Cu, Zn, Fe, Mn, Cr, Cd, Ni, Co and Pb) in soil, vegetables and the water used for irrigation at two sites (Laelay Wukro and Tahtay Wukro) around Wukro Town, Tigray, Northern Ethiopia. The concentrations of heavy metals in irrigation water measured during this study were lower than permissible limits of heavy metals allowed for irrigation water. The mean concentrations of heavy metals in irrigated soil samples obtained from Tahtay Wukro were higher for Mn, Zn, Cr, and Cu. The overall results of soil samples ranged 2.62-827, 1.4-51.6, 25.5-33.6, 23.5-28.2, 2.52-25.1, 15-17.8, 3-4, 2.5-40.49 and 0.7-0.8 mg/kg for Mn, Zn, Cr, Ni, Cu, Co, Pb, Fe and Cd, respectively. Higher concentrations of heavy metals were also observed in vegetable samples from Tahtay Wukro. Pb was found to accumulate the most in all vegetable samples. It was observed that green pepper and lettuce accumulate high amounts of Cu and Zn; Swiss chard accumulates excessive amounts of Fe, Mn, Cr, Cd, Ni and Co; lettuce and tomato higher amounts of Cd; and green pepper, tomato and onion a higher concentration of Pb. Significant differences in the elemental concentrations between the vegetables analyzed from Laelay and Tahtay Wukro were observed. This was attributed in part to the geological nature of the study area and the discharges from the town and from a tannery. The results also indicate that Fe, Pb and Cd have high transfer factor values (mean values: 42.89, 0.84 and 0.37, respectively). The transfer pattern for heavy metals in different vegetables showed a trend in the order: Fe>Pb>Cd>Mn>Cu>Zn>Ni>Zn>Cr=Co. The heavy metal contamination of vegetables grown in Tahtay Wukro, located downstream of the tannery, may pose increased health risks in the future to the local population

  6. Assessment of Heavy Metal Contamination in Vegetables Grown Using Paper Mill Wastewater in Wonji Gefersa, Ethiopia.

    PubMed

    Eliku, Temesgen; Leta, Seyoum

    2016-11-01

    Heavy metals are among the major contaminants of vegetables. A study was conducted at Wonji Gefersa farms where paper wastewater is used for cultivation of vegetable crops. Four vegetable samples, namely Swiss chard, carrot, tomato, green pepper, as well as paper wastewater were examined for heavy metal [Lead (Pb), Zinc (Zn), Cadmium (Cd), Iron (Fe), Copper (Cu), Chromium (Cr) and Cobalt (Co)] contamination using atomic absorption spectroscopy. The levels of Pb, Cd and Cr in paper wastewater were all above the safe limit for FAO standards for wastewater quality for irrigation. The concentration of Pb in Swiss chard and Green peeper was exceeded the permissible limits. The study reveals that Pb metal contamination in the study area which poses health risk with time unless an urgent step is taken by relevant agencies to address this issue.

  7. Efficiency of a novel "Food to waste to food" system including anaerobic digestion of food waste and cultivation of vegetables on digestate in a bubble-insulated greenhouse.

    PubMed

    Stoknes, K; Scholwin, F; Krzesiński, W; Wojciechowska, E; Jasińska, A

    2016-10-01

    At urban locations certain challenges are concentrated: organic waste production, the need for waste treatment, energy demand, food demand, the need for circular economy and limited area for food production. Based on these factors the project presented here developed a novel technological approach for processing organic waste into new food. In this system, organic waste is converted into biogas and digester residue. The digester residue is being used successfully as a stand-alone fertilizer as well as main substrate component for vegetables and mushrooms for the first time - a "digeponics" system - in a closed new low energy greenhouse system with dynamic soap bubble insulation. Biogas production provides energy for the process and CO2 for the greenhouse. With very limited land use highly efficient resource recycling was established at pilot scale. In the research project it was proven that a low energy dynamic bubble insulated greenhouse can be operated continuously with 80% energy demand reduction compared to conventional greenhouses. Commercial crop yields were achieved based on fertilization with digestate; in individual cases they were even higher than the control yields of vegetables such as tomatoes, cucumber and lettuce among others. For the first time an efficient direct use of digestate as substrate and fertilizer has been developed and demonstrated.

  8. Characterization of free nitrogen fixing bacteria of the genus Azotobacter in organic vegetable-grown Colombian soils.

    PubMed

    Jiménez, Diego Javier; Montaña, José Salvador; Martínez, María Mercedes

    2011-07-01

    With the purpose of isolating and characterizing free nitrogen fixing bacteria (FNFB) of the genus Azotobacter, soil samples were collected randomly from different vegetable organic cultures with neutral pH in different zones of Boyacá-Colombia. Isolations were done in selective free nitrogen Ashby-Sucrose agar obtaining a recovery of 40%. Twenty four isolates were evaluated for colony and cellular morphology, pigment production and metabolic activities. Molecular characterization was carried out using amplified ribosomal DNA restriction analysis (ARDRA). After digestion of 16S rDNA Y1-Y3 PCR products (1487pb) with AluI, HpaII and RsaI endonucleases, a polymorphism of 16% was obtained. Cluster analysis showed three main groups based on DNA fingerprints. Comparison between ribotypes generated by isolates and in silico restriction of 16S rDNA partial sequences with same restriction enzymes was done with Gen Workbench v.2.2.4 software. Nevertheless, Y1-Y2 PCR products were analysed using BLASTn. Isolate C5T from tomato (Lycopersicon esculentum) grown soils presented the same in silico restriction patterns with A. chroococcum (AY353708) and 99% of similarity with the same sequence. Isolate C5CO from cauliflower (Brassica oleracea var. botrytis) grown soils showed black pigmentation in Ashby-Benzoate agar and high similarity (91%) with A. nigricans (AB175651) sequence. In this work we demonstrated the utility of molecular techniques and bioinformatics tools as a support to conventional techniques in characterization of the genus Azotobacter from vegetable-grown soils.

  9. Characterization of free nitrogen fixing bacteria of the genus Azotobacter in organic vegetable-grown Colombian soils

    PubMed Central

    Jiménez, Diego Javier; Montaña, José Salvador; Martínez, María Mercedes

    2011-01-01

    With the purpose of isolating and characterizing free nitrogen fixing bacteria (FNFB) of the genus Azotobacter, soil samples were collected randomly from different vegetable organic cultures with neutral pH in different zones of Boyacá-Colombia. Isolations were done in selective free nitrogen Ashby-Sucrose agar obtaining a recovery of 40%. Twenty four isolates were evaluated for colony and cellular morphology, pigment production and metabolic activities. Molecular characterization was carried out using amplified ribosomal DNA restriction analysis (ARDRA). After digestion of 16S rDNA Y1-Y3 PCR products (1487pb) with AluI, HpaII and RsaI endonucleases, a polymorphism of 16% was obtained. Cluster analysis showed three main groups based on DNA fingerprints. Comparison between ribotypes generated by isolates and in silico restriction of 16S rDNA partial sequences with same restriction enzymes was done with Gen Workbench v.2.2.4 software. Nevertheless, Y1-Y2 PCR products were analysed using BLASTn. Isolate C5T from tomato (Lycopersicon esculentum) grown soils presented the same in silico restriction patterns with A. chroococcum (AY353708) and 99% of similarity with the same sequence. Isolate C5CO from cauliflower (Brassica oleracea var. botrytis) grown soils showed black pigmentation in Ashby-Benzoate agar and high similarity (91%) with A. nigricans (AB175651) sequence. In this work we demonstrated the utility of molecular techniques and bioinformatics tools as a support to conventional techniques in characterization of the genus Azotobacter from vegetable-grown soils. PMID:24031700

  10. Spherical Lactic Acid-producing Bacteria of Southern-grown Raw and Processed Vegetables

    PubMed Central

    Mundt, J. Orvin; Graham, Wanda F.; McCarty, I. E.

    1967-01-01

    The frequency and levels of population of the spherical lactic acid-producing bacteria were determined on raw and processed yellow summer and zucchini squash, a variety of greens, green beans, okra, southern peas, and butter and lima beans, and on fresh cucumbers and corn flowers. Six taxa occurred consistently: Leuconostoc mesenteroides, yellow-pigmented streptococci, Streptococcus faecium, Aerococcus viridans, and S. faecalis and S. faecalis var. liquefaciens. The same taxa occurred with the same order of frequency on processed, frozen vegetables, but with a marked decrease in the occurrence of S. faecalis var. liquefaciens. S. lactis, S. cremoris, S. equinus, S. bovis, and pediococci were isolated infrequently. No other member of the viridans group of the streptococci and no member of the pyogenic group was isolated. Approximately 88% of the cultures were identified. Total counts of the lactic-acid-producing bacteria rarely exceeded 105 per gram of sample, and there was a reduction by 90% during the second year of study, probably because of drought. Only one bacterial species was found on 40% of the raw and 34% of the processed vegetable samples. Two or more species or taxa were present on the remainder of 153 raw and 56 processed vegetable samples. A. viridans was present on squash, greens, okra, and southern peas, and its frequency of occurrence on vegetables suggests that plants are its natural habitat. PMID:16349739

  11. Solar greenhouse project. Final technical report

    SciTech Connect

    Not Available

    1983-06-03

    Three (3) passive solar greenhouses were constructed as lean-to attachment to the homes of three (3) low-income families in Mecklenburg County, North Carolina as a demonstration project. CETA labor was provided by a training and work experience project for home repair and construction skills. Some of the walls were constructed from old salvaged windows and a local block company donated blocks that were used for the foundation. Recipients of the greenhouses reported reduced air drafts and fuel consumption savings. Flowers and vegetables were successfully grown during the winter months.

  12. Accumulation of cadmium in the edible parts of six vegetable species grown in Cd-contaminated soils.

    PubMed

    Yang, Yong; Zhang, Fu-Suo; Li, Hua-Fen; Jiang, Rong-Feng

    2009-02-01

    Species difference in Cd accumulation is important for selection of agronomic technologies aimed at producing low-Cd vegetables. Six vegetable species (Chinese leek, pakchoi, carrot, radish, tomato and cucumber) were grown in pot and field experiments to study the accumulation of Cd under different conditions. In the field trial (Cd 2.55 mg kg(-1)), Cd concentrations in the edible parts ranged from 0.01 to 0.1 mg kg(-1) and were below the permissible limits (0.2 mg kg(-1) for pakchoi and leek; 0.1 mg kg(-1) for carrot and radish; 0.05 mg kg(-1) for cucumber and tomato), but exceeded the limit in pakchoi, Chinese leek, carrot and tomato at a Cd addition level of 2.0 mg kg(-1). Plant Cd concentrations increased linearly with the increasing concentration of Cd added to the soil, with the slope of the regression lines varying by 28-fold among the six species. The bioconcentration factor (BCF) varied substantially, and was much higher in the pot experiment than in the field trial. It is concluded that the vegetable species differed markedly in the Cd accumulation and species performed consistently under different growth conditions.

  13. Greenhouse (III): Gas-Exchange and Seed-to-Seed Experiments on the Russian Space Station MIR and Earth-grown, Ethylene-Treated Wheat Plants

    NASA Technical Reports Server (NTRS)

    Campbell, William F.; Bingham, Gail; Carman, John; Bubenheim, David; Levinskikh, Margarita; Sytchev, Vladimir N.; Podolsky, Igor B.; Chernova, Lola; Nefodova, Yelena

    2001-01-01

    The Mir Space Station provided an outstanding opportunity to study long-term plant responses when exposed to a microgravity environment. Furthermore, if plants can be grown to maturity in a microgravity environment, they might be used in future bioregenerative life-support systems (BLSS). The primary objective of the Greenhouse experiment onboard Mir was to grow Super Dwarf and Apogee wheat through complete life cycles in microgravity; i.e., from seed-to-seed-to-seed. Additional objectives were to study chemical, biochemical, and structural changes in plant tissues as well as photosynthesis, respiration, and transpiration (evaporation of water from plants). Another major objective was to evaluate the suitability clothe facilities on Mir for advanced research with plants. The Greenhouse experiment was conducted in the Russian/Bulgarian plant growth chamber, the Svet, to which the United States added instrumentation systems to monitor changes in CO2 and water vapor caused by the plants (with four infrared gas analyzers monitoring air entering and leaving two small plastic chambers). In addition, the US instrumentation also monitored O2; air, leaf (IR), cabin pressure; photon flux; and substrate temperature and substrate moisture (16 probes in the root module). Facility modifications were first performed during the summer of 1995 during Mir 19, which began after STS-72 left Mir. Plant development was monitored by daily observations and some photographs.

  14. Build a Solar Greenhouse.

    ERIC Educational Resources Information Center

    Conservation and Renewable Energy Inquiry and Referral Service (DOE), Silver Spring, MD.

    Attached solar greenhouses are relatively inexpensive and easy to build; they can provide additional heat to homes all winter as well as fresh vegetables and flowers. This bulletin: (1) describes the characteristics of a solar greenhouse; (2) provides a checklist of five items to consider before building a solar greenhouse; (3) describes the four…

  15. [Concentration and distribution of PAHs in vegetables grown near an iron and steel industrial area].

    PubMed

    Shen, Fei; Zhu, Li-Zhong

    2007-03-01

    Concentrations of 15 kinds of polycyclic aromatic hydrocarbon (PAHs) were determined in 8 vegetable species and their growing environment (soil and atmosphere) near an iron and steel industrial area. The total concentrations of 15 kinds of PAHs (sigma PAHs) were 227.1 - 1 533.2 ng/g, 759.1 ng/g in average. The concentrations of 8 carcinogenic PAHs (sigma carePAHs) were 7.1 - 231.2 ng/g, 70.6 ng/g in average. Of the various vegetable species determined, the highest polyaromatic burden was observed in the leafy vegetables, followed by melon and fruit species, while the rhizome species accumulated the lowest amount. In melon and fruit species, most PAHs were accumulated on the peel, only about 30% transfer into the core. The ability of the plant accumulating PAHs was mainly influenced by the lipid content of the plant. Leaf with pubescence or rough surface was found to have higher sigma PAHs than the other, and the fibre higher than the taproot, when the lipid contents were close.

  16. Environmental surveillance of commonly-grown vegetables for investigating potential lead and chromium contamination intensification in Bangladesh.

    PubMed

    Hossain, A M M Maruf; Islam, M Shahidul; Mamun, M Mustafa; Al-Jonaed, H M; Imran, M; Rahman, M Hasibur; Kazi, M Azizul Islam; Elahi, Syed Fazle

    2016-01-01

    With regard to previously reported Lead (Pb) and Chromium (Cr) contamination in egg, a semi-quantitative assessment of the general environment of Bangladesh is carried out through nation-wide sampling of commonly grown and consumed vegetables. Five vegetables, namely, White Potato (Solanum tuberosum), Green Cabbage (Brassica oleracea capitata var. alba L.), Red Spinach (Amaranthus dubius), White Radish (Raphanus sativus var. longipinnatus), and Green Bean (Phaseolus vulgaris) were selected for sampling from all 64 Districts of the country as per their availability during the sampling season. This results in a collection of 292 samples. Due to the necessity of incorporating a wide spectrum of vegetable types (e.g. tuber, brassica, leafy, root, and fruiting vegetables) as well as the need for including the geographic expanse of the whole country, replicates were not accommodated in the study, hence, the study being semi-quantitative in nature. The results do not substantiate evidence of public health risk due to Cr yet, with only 0.69 % of the samples found contaminated with Cr. Pb contamination (concentrations above a health-based guidance value) is found in 29.47 % of the samples; and together with the insight of such contamination likely being non-point origin, communicates on potential public health risk due to Pb as residual effects of extensive ambient atmospheric Pb pollution in recent history of the country. For the purpose of comparison, Cadmium (Cd) contents of the samples are also analyzed. Although there is no extensive Cd pollution history/source in the country, the likely point-source nature of Cd contamination found in 17.83 % of the samples indicates the scope of managing any existing contamination source by directing efforts into the potential point-sources.

  17. Analysis of vegetable seedlings grown in contact with Apollo 14 lunar surface fines.

    NASA Technical Reports Server (NTRS)

    Walkinshaw, C. H.; Johnson, P. H.

    1971-01-01

    Study of plant seedlings treated with lunar material, grown for 14 to 21 days, and then subjected to chemical analyses and other measurements. The purpose of the study was to determine whether plants growing in contact with lunar-surface fines contained a different elemental composition compared with untreated seedlings. The results indicate a direct interaction between germfree plants and lunar material. Treated plants dissolved and absorbed significant quantities of Al, Fe, and Ti from the lunar fines. Cabbage and Brussel sprouts were particularly efficient in the dissolution and absorption of Mn.

  18. Analysis of vegetable seedlings grown in contact with Apollo 14 lunar surface fines.

    NASA Technical Reports Server (NTRS)

    Walkinshaw, C. H.; Johnson, P. H.

    1971-01-01

    Study of plant seedlings treated with lunar material, grown for 14 to 21 days, and then subjected to chemical analyses and other measurements. The purpose of the study was to determine whether plants growing in contact with lunar-surface fines contained a different elemental composition compared with untreated seedlings. The results indicate a direct interaction between germfree plants and lunar material. Treated plants dissolved and absorbed significant quantities of Al, Fe, and Ti from the lunar fines. Cabbage and Brussel sprouts were particularly efficient in the dissolution and absorption of Mn.

  19. The Influence of Sun Position and Clouds on Reflectance and Vegetation Indices of Greenhouse-Grown Corn

    USDA-ARS?s Scientific Manuscript database

    The reflectance characteristics of plants and plant canopies far from solar noon or with cloudy skies are not well known. This is an obstacle to making real-time variable-rate N fertilizer applications based on canopy reflectance because such a system must work under cloudy skies and at all times of...

  20. Boron nutrition and mobility, and its relation to the elemental composition of greenhouse grown root crops I. rutabaga

    SciTech Connect

    Shelp, B.J.; Shattuck, V.I.

    1987-01-01

    The nutrition and mobility of B, and its relation to the elemental composition of two cultivars of rutabaga (Brassica napus ssp. rapifera cv. Laurentian and Wilhelmsberger) plants were investigated in greenhouse experiments. Laurentian exhibited a greater response than Wilhelmsberger to continuing B deficiency as indicated by the severity in the roots of brown heart, of external roughness and elongation and of the decrease in B concentration. Signs of B deficiency were not found when the B contents of the root and young leaves were 27 and 56 ..mu..g and g/sup -1/ DM respectively. Root B levels of 14 and 17-20 ..mu..g f/sup -1/ gave moderate and slight internal signs of brown discoloration. Foliar applications of B partially restored the B concentrations of the roots; however, the mechanisms of movement was unclear. The Mg, Mn and Zn contents of roots were the only elements that consistently increased and accumulated under B deficiency. The relative element composition of the root compared to the mature leaves is consistent with the root being supplied predominantly with nutrients by the phloem.

  1. Field measurements of key parameters associated with nocturnal OBT formation in vegetables grown under Canadian conditions.

    PubMed

    Kim, S B; Workman, W G; Korolevych, V; Davis, P A

    2012-02-01

    The objective of this study was to provide the parameter values required to model OBT formation in the edible parts of plants following a hypothetical accidental tritium release to the atmosphere at night. The parameters considered were leaf area index, stomatal resistance, photosynthesis rate, the photosynthetic production rate of starch, the nocturnal hydrolysis rate of starch, the fraction of starch produced daily by photosynthesis that appears in the fruits, and the mass of the fruit. Values of these parameters were obtained in the summer of 2002 for lettuce, radishes and tomatoes grown under typical Canadian environmental conditions. Based on the maximum observed photosynthetic rate and growth rate, the fraction of starch translocated to the fruit was calculated to be 17% for tomato fruit and 14% for radish root. Copyright © 2011 Elsevier Ltd. All rights reserved.

  2. Soil versus foliar iodine fertilization as a biofortification strategy for field-grown vegetables.

    PubMed

    Lawson, Patrick G; Daum, Diemo; Czauderna, Roman; Meuser, Helmut; Härtling, Joachim W

    2015-01-01

    Iodine (I) biofortification of vegetables by means of soil and foliar applications was investigated in field experiments on a sandy loam soil. Supply of iodine to the soil in trial plots fertilized with potassium iodide (KI) and potassium iodate directly before planting (0, 1.0, 2.5, 7.5, and 15 kg I ha(-1)) increased the iodine concentration in the edible plant parts. The highest iodine accumulation levels were observed in the first growing season: In butterhead lettuce and kohlrabi the desired iodine content [50-100 μg I (100 g FM)(-1)] was obtained or exceeded at a fertilizer rate of 7.5 kg IO3 (-)-I ha(-1) without a significant yield reduction or impairment of the marketable quality. In contrast, supplying KI at the same rate resulted in a much lower iodine enrichment and clearly visible growth impairment. Soil applied iodine was phytoavailable only for a short period of time as indicated by a rapid decline of CaCl2-extractable iodine in the top soil. Consequently, long-term effects of a one-time iodine soil fertilization could not be observed. A comparison between the soil and the foliar fertilization revealed a better performance of iodine applied aerially to butterhead lettuce, which reached the desired iodine accumulation in edible plant parts at a fertilizer rate of 0.5 kg I(-)-I ha(-1). In contrast, the iodine content in the tuber of sprayed kohlrabi remained far below the targeted range. The results indicate that a sufficient spreading of iodine applied on the edible plant parts is crucial for the efficiency of the foliar approach and leafy vegetables are the more suitable target crops. The low iodine doses needed as well as the easy and inexpensive application may favor the implementation of foliar sprays as the preferred iodine biofortification strategy in practice.

  3. Soil versus foliar iodine fertilization as a biofortification strategy for field-grown vegetables

    PubMed Central

    Lawson, Patrick G.; Daum, Diemo; Czauderna, Roman; Meuser, Helmut; Härtling, Joachim W.

    2015-01-01

    Iodine (I) biofortification of vegetables by means of soil and foliar applications was investigated in field experiments on a sandy loam soil. Supply of iodine to the soil in trial plots fertilized with potassium iodide (KI) and potassium iodate directly before planting (0, 1.0, 2.5, 7.5, and 15 kg I ha-1) increased the iodine concentration in the edible plant parts. The highest iodine accumulation levels were observed in the first growing season: In butterhead lettuce and kohlrabi the desired iodine content [50–100 μg I (100 g FM)-1] was obtained or exceeded at a fertilizer rate of 7.5 kg IO3--I ha-1 without a significant yield reduction or impairment of the marketable quality. In contrast, supplying KI at the same rate resulted in a much lower iodine enrichment and clearly visible growth impairment. Soil applied iodine was phytoavailable only for a short period of time as indicated by a rapid decline of CaCl2-extractable iodine in the top soil. Consequently, long-term effects of a one-time iodine soil fertilization could not be observed. A comparison between the soil and the foliar fertilization revealed a better performance of iodine applied aerially to butterhead lettuce, which reached the desired iodine accumulation in edible plant parts at a fertilizer rate of 0.5 kg I--I ha-1. In contrast, the iodine content in the tuber of sprayed kohlrabi remained far below the targeted range. The results indicate that a sufficient spreading of iodine applied on the edible plant parts is crucial for the efficiency of the foliar approach and leafy vegetables are the more suitable target crops. The low iodine doses needed as well as the easy and inexpensive application may favor the implementation of foliar sprays as the preferred iodine biofortification strategy in practice. PMID:26157445

  4. Assessment of Total Phenolic and Flavonoid Content, Antioxidant Properties, and Yield of Aeroponically and Conventionally Grown Leafy Vegetables and Fruit Crops: A Comparative Study

    PubMed Central

    Chandra, Suman; Khan, Shabana; Avula, Bharathi; Lata, Hemant; Yang, Min Hye; ElSohly, Mahmoud A.; Khan, Ikhlas A.

    2014-01-01

    A comparison of the product yield, total phenolics, total flavonoids, and antioxidant properties was done in different leafy vegetables/herbs (basil, chard, parsley, and red kale) and fruit crops (bell pepper, cherry tomatoes, cucumber, and squash) grown in aeroponic growing systems (AG) and in the field (FG). An average increase of about 19%, 8%, 65%, 21%, 53%, 35%, 7%, and 50% in the yield was recorded for basil, chard, red kale, parsley, bell pepper, cherry tomatoes, cucumber, and squash, respectively, when grown in aeroponic systems, compared to that grown in the soil. Antioxidant properties of AG and FG crops were evaluated using 2,2-diphenyl-1-picrylhydrazyl (DDPH) and cellular antioxidant (CAA) assays. In general, the study shows that the plants grown in the aeroponic system had a higher yield and comparable phenolics, flavonoids, and antioxidant properties as compared to those grown in the soil. PMID:24782905

  5. The expansion of Phytophthora clade 8b: three new species associated with winter grown vegetable crops.

    PubMed

    Bertier, L; Brouwer, H; de Cock, A W A M; Cooke, D E L; Olsson, C H B; Höfte, M

    2013-12-01

    Despite its association with important agricultural crops, Phytophthora clade 8b is a poorly studied group of species. The clade currently consists of three officially described species (Phytophthora porri, P. brassicae and P. primulae) that are host-specific pathogens of leek, cabbages and Primula spp., respectively. However, over the past few decades, several other clade 8b-like Phytophthoras have been found on a variety of different host plants that were all grown at low temperatures in winter seasons. In this study, a collection of 30 of these isolates was subjected to a phylogenetic study using two loci (the rDNA ITS region and the mitochondrial cox1 gene). This analysis revealed a clear clustering of isolates according to their host plants. To verify whether these isolates belong to separate species, a detailed morphological study was conducted. On the basis of genetic and morphological differences and host specificity, we now present the official description of three new species in clade 8b: Phytophthora cichorii sp. nov., P. dauci sp. nov. and P. lactucae sp. nov. Two other groups of isolates (Phytophthora taxon castitis and Phytophthora taxon parsley) might also represent new species but the data available at this time are insufficient for an official description. This brings Phytophthora clade 8b to a group of six species that are all host-specific, slow-growing and specifically infect herbaceous crops at low temperatures.

  6. Content of Cadmium and Lead in Vegetables and Fruits Grown in the Campania Region of Italy.

    PubMed

    Esposito, Mauro; Picazio, Giuseppe; Serpe, Paola; Lambiase, Sara; Cerino, Pellegrino

    2015-09-01

    Illegal practices of waste combustion and their burial in some land devoted to agricultural crops caused a severe economic crisis of the agriculture and food sector in the Campania region of Italy. To assess the levels of contamination by lead and cadmium, the only metals subject to European Union legislation, a system of monitoring of plant foods in the whole territory of the region has been promoted, with the goal of certifying productions and consumer protection. In fact, products that comply with European Union standards are assigned a Quick Response Code, which guarantees the traceability of the product (manufacturer and location). The code also ensures the safety of the product, as it allows the consumer to see the results of the analysis performed on the specific chain of production. The content of lead and cadmium was determined in 750 vegetable samples by using the atomic absorption spectrophotometry after microwave mineralization. These levels were below the maximum limits in all but three samples; two samples of tomatoes exceeded the maximum level of cadmium, and one sample of valerian contained an excess of lead.

  7. Phthalate esters contamination in soils and vegetables of plastic film greenhouses of suburb Nanjing, China and the potential human health risk.

    PubMed

    Ma, Ting Ting; Wu, Long Hua; Chen, Like; Zhang, Hai Bo; Teng, Ying; Luo, Yong Ming

    2015-08-01

    The contamination of phthalate esters (PAEs) has become a potential threat to the environment and human health because they could be easily released as plasticizers from the daily supply products, especially in polyethylene films. Concentration levels of total six PAEs, nominated as priority pollutants by the US Environmental Protection Agency (USEPA), were investigated in soils and vegetables from four greenhouse areas in suburbs of Nanjing, East China. Total PAEs concentration ranged from 930 ± 840 to 2,450 ± 710 μg kg(-1) (dry weight (DW)) in soil and from 790 ± 630 to 3,010 ± 2,130 μg kg(-1) in vegetables. Higher concentrations of PAEs were found in soils except in Suo Shi (SS) area and in vegetables, especially in potherb mustard and purple tsai-tai samples. Risk assessment mainly based on the exposures of soil ingestion and daily vegetable intake indicated that bis(2-ethylhexyl) phthalate (DEHP) in the samples from Gu Li (GL) and Hu Shu (HS) exhibited the highest hazard to children less than 6-year old. Therefore, the human health risk of the PAEs contamination in soils and vegetables should greatly be of a concern, especially for their environmental estrogen analog effects.

  8. Short-term fluctuations in vegetation and phytoplankton during the Middle Eocene greenhouse climate: a 640-kyr record from the Messel oil shale (Germany)

    NASA Astrophysics Data System (ADS)

    Lenz, Olaf K.; Wilde, Volker; Riegel, Walter

    2011-11-01

    The Palaeogene was the most recent greenhouse period on Earth. Especially for the Late Palaeocene and Early Eocene, several superimposed short-term hyperthermal events have been described, including extremes such as the Palaeocene-Eocene Thermal Maximum. Major faunal and floral turnovers in the marine and terrestrial realms were recorded in association with these events. High-resolution palynological analysis of the early Middle Eocene maar lake sediments at Messel, near Darmstadt, Germany, provides an insight into the dynamics of a climax vegetation during the Middle Eocene greenhouse climate in a time span without significant climatic excursions. Numerical techniques like detrended correspondence analysis and wavelet analysis have been applied to recognize cyclic fluctuations and long-term trends in the vegetation through a time interval of approximately 640 kyr. Based on the numerical zoning of the pollen diagram, three phases in the development of the vegetation may be distinguished. Throughout these phases, the climax vegetation did not change substantially in qualitative composition, but a trend towards noticeably less humid conditions probably in combination with a drop of the water level in the lake may be recognized. A shift in algal population from the freshwater dinoflagellate cyst Messelodinium thielepfeifferae to a dominance of Botryococcus in the uppermost part of the core is interpreted as a response to changes in acidity and nutrient availability within the lake. Time series analyses of pollen assemblages show that variations in the Milankovitch range of eccentricity, obliquity and precession can be distinguished. In addition, fluctuations in the sub-Milankovitch range are indicated. This demonstrates that floral changes during steady depositional conditions in the Middle Eocene of Messel were controlled by orbital forcing.

  9. Fungicidal activities of soil humic/fulvic acids as related to their chemical structures in greenhouse vegetable fields with cultivation chronosequence

    NASA Astrophysics Data System (ADS)

    Wu, Meng; Song, Mengya; Liu, Ming; Jiang, Chunyu; Li, Zhongpei

    2016-09-01

    In the background of rapid expansion of plastic greenhouse vegetable production in China, many environmental risks have emerged in recent years. In this study, the soils with a chronosequence in greenhouse vegetable fields were collected and the soil humic acids (HAs) and fluvic acids (FAs) were extracted and purified. The soil HAs and FAs were found to show inhibition activities against phytopathogenic fungi for the first time. Fourier transform infrared spectroscopy was performed to investigate the chemical structures of HAs and FAs. The variation of relative peak areas indicated the chemical structure of HAs become more complex and stable under continuous cultivation. The PCA analysis showed HAs and FAs could be distinctly separated from each other and cultivation years mainly determined the variation. Mantel test and RDA analysis indicated the active components (aliphatic peaks for HAs and COOH, OH peaks for FAs) had positive correlation with the inhibition rates of HAs and FAs against phytopathogenic fungi. According to our research, the active fungicidal components in soil HAs and FAs decreased along with the extension of cultivation years, which made the soil suffer more risk to phytopathogenic fugi. So we believe continuous cultivation too many years in PGVP systems is inadvisable.

  10. Fungicidal activities of soil humic/fulvic acids as related to their chemical structures in greenhouse vegetable fields with cultivation chronosequence

    PubMed Central

    Wu, Meng; Song, Mengya; Liu, Ming; Jiang, Chunyu; Li, Zhongpei

    2016-01-01

    In the background of rapid expansion of plastic greenhouse vegetable production in China, many environmental risks have emerged in recent years. In this study, the soils with a chronosequence in greenhouse vegetable fields were collected and the soil humic acids (HAs) and fluvic acids (FAs) were extracted and purified. The soil HAs and FAs were found to show inhibition activities against phytopathogenic fungi for the first time. Fourier transform infrared spectroscopy was performed to investigate the chemical structures of HAs and FAs. The variation of relative peak areas indicated the chemical structure of HAs become more complex and stable under continuous cultivation. The PCA analysis showed HAs and FAs could be distinctly separated from each other and cultivation years mainly determined the variation. Mantel test and RDA analysis indicated the active components (aliphatic peaks for HAs and COOH, OH peaks for FAs) had positive correlation with the inhibition rates of HAs and FAs against phytopathogenic fungi. According to our research, the active fungicidal components in soil HAs and FAs decreased along with the extension of cultivation years, which made the soil suffer more risk to phytopathogenic fugi. So we believe continuous cultivation too many years in PGVP systems is inadvisable. PMID:27597259

  11. Fungicidal activities of soil humic/fulvic acids as related to their chemical structures in greenhouse vegetable fields with cultivation chronosequence.

    PubMed

    Wu, Meng; Song, Mengya; Liu, Ming; Jiang, Chunyu; Li, Zhongpei

    2016-09-06

    In the background of rapid expansion of plastic greenhouse vegetable production in China, many environmental risks have emerged in recent years. In this study, the soils with a chronosequence in greenhouse vegetable fields were collected and the soil humic acids (HAs) and fluvic acids (FAs) were extracted and purified. The soil HAs and FAs were found to show inhibition activities against phytopathogenic fungi for the first time. Fourier transform infrared spectroscopy was performed to investigate the chemical structures of HAs and FAs. The variation of relative peak areas indicated the chemical structure of HAs become more complex and stable under continuous cultivation. The PCA analysis showed HAs and FAs could be distinctly separated from each other and cultivation years mainly determined the variation. Mantel test and RDA analysis indicated the active components (aliphatic peaks for HAs and COOH, OH peaks for FAs) had positive correlation with the inhibition rates of HAs and FAs against phytopathogenic fungi. According to our research, the active fungicidal components in soil HAs and FAs decreased along with the extension of cultivation years, which made the soil suffer more risk to phytopathogenic fugi. So we believe continuous cultivation too many years in PGVP systems is inadvisable.

  12. Spatial variation related to hydroloigc patterns and vegetation in greenhouse gas fluxes from the Mississippi Delta agricultural region

    USDA-ARS?s Scientific Manuscript database

    Methane (CH4), nitrous oxide (N2O), and carbon dioxide (CO2) fluxes from agricultural landscapes may contribute significantly to regional greenhouse gas budgets due to stimulation of soil microbial activity through fertilizer application and variable soil moisture effects. In this study, measuremen...

  13. [Level of cadmium and lead in vegetables, fruit, cereal and soil from areas differing in the degree of industrial pollution and from greenhouses].

    PubMed

    Szymczak, J; Ilow, R; Regulska-Ilow, B

    1993-01-01

    The content of cadmium and lead was measured in vegetables, fruit, cereals and soil from areas exposed and non-exposed to industrial pollution and in vegetables and soil from greenhouses. The elements were measured after dry mineralization by atomic absorption spectrophotometry following extraction of complexes from APDS into the organic phase (MIBK). Lead and cadmium were determined in 482 samples of vegetables, 101 fruit samples, 132 cereal samples and 297 soil samples. In the vegetables from the areas not exposed to industrial pollution lead content was below the detectability range (< d.r.) to 576.1 micrograms/kg, and cadmium was from < d.r. to 73.5 micrograms/kg. In the vegetables from areas exposed to industrial pollution lead was from 9.3 to 1044.0 micrograms/kg and cadmium from < d.r. to 552.3 micrograms/kg and cadmium from 2.3 to 132.5 micrograms/kg. In the soil from greenhouses lead was found in amounts from 17.5 to 212.0 mg/kg of air dry mass (adm), and cadmium from 125 to 750 micrograms/kg of adm. In soil from vegetable gardens lead was from 3.3 to 15.3 mg/kg of adm., and cadmium from < d.r. to 385.0 mu/kg adm. In soil from orchards lead was from 2.8 to 141.3 mg/kg adm, and cadmium from < d.r. to 810.0 micrograms/kg adm. In the soil from fields of cereals lead was from 3.0 to 67.5 mg/kg amd, and cadmium from < d.r. to 295.0 micrograms/kg adm. In fruit lead was present in amounts from 12.8 to 144.0 micrograms/kg and cadmium from < d.r. to 42.0 micrograms/kg. In cereals lead was found in amounts from < d.r. to 760.0 micrograms/kg and cadmium from < d.r. to 200 micrograms/kg.

  14. Characterization and detection of emerging viroids in North American greenhouse tomatoes

    USDA-ARS?s Scientific Manuscript database

    Tomato is an economically important vegetable in many countries around the world, with major productions in China, the U.S., Spain, Italy, India, Turkey, and Egypt. Although, most of the tomato production is field grown, there is a growing trend in protective production (greenhouse). Nearly 40% of...

  15. Food Safety and Bioavailability Evaluations of Four Vegetables Grown in the Highly Arsenic-Contaminated Soils on the Guandu Plain of Northern Taiwan

    PubMed Central

    Su, Shaw-Wei; Tsui, Chun-Chih; Lai, Hung-Yu; Chen, Zueng-Sang

    2014-01-01

    Arsenic contamination in a large area of agricultural fields on the Guandu Plain of northern Taiwan was confirmed in a survey conducted in 2006, but research concerning the relationship between bioavailable As concentrations in contaminated soils and crop production in Taiwan is not available. Pot experiments were conducted to examine the growth and accumulation of As in four vegetable crops grown in As-contaminated soils and to assess As intake through consumption. The phytotoxic effects of As in soils were not shown in the pot experiments in which vegetable crops were grown in soils contaminated with different As levels in situ collected from Guandu Plain (120–460 mg/kg) or artificially spiked As-contaminated soils (50–170 mg/kg). Experimental results showed that the bioavailable As extracted with 5 M NaHCO3 from soils can be used to estimate As concentrations in vegetables. The As concentrations in the vegetables were compared with data shown in the literature and As limits calculated from drinking water standards and the provisional tolerance weekly intake (PTWI) of inorganic As established by the Food and Agriculture Organization of the United Nations/World Health Organization (FAO/WHO). Although the As levels in the vegetables were not high and the bioavailability of As in the soils was quite low, long-term consumption may result in higher As intake in the human body. PMID:24736690

  16. Health risk assessment of heavy metals for edible parts of vegetables grown in sewage-irrigated soils in suburbs of Baoding City, China.

    PubMed

    Xue, Zhan-Jun; Liu, Shu-Qing; Liu, Yan-Ling; Yan, Yong-Lu

    2012-06-01

    With the long-term application of wastewater to vegetable production fields, there is concern about potential health risks of heavy metals contaminating the edible parts of vegetables grown in contaminated soils in the suburban areas of Baoding City, China. The average concentration of elemental Zn in sewage-irrigated soil was the highest (153.77 mg kg(-1)), followed by Pb (38.35 mg kg(-1)), Cu (35.06 mg kg(-1)), Ni (29.81 mg kg(-1)), and Cd (0.22 mg kg(-1)) which were significantly higher (P < 0.05) than those in the reference soil. The results showed that long-term sewage irrigation had led to a growing accumulation of heavy metals in the soils, especially for Cd, Zn, and Pb. Furthermore, the concentrations of elemental Cd, Zn, and Ni in vegetables (e.g., Beassica pekinensis L., Allium fistulosum L., Spinacia oleracea L.) collected from the wastewater-irrigated soils exceeded the maximum permissible limits, and this also increased the daily intake of metals by food. However, compared with the health risk index of <1 for heavy metals, the ingestion of vegetables from the soils irrigated with sewage effluent posed a low health risk. Nevertheless, heavy metal concentrations should be periodically monitored in vegetables grown in these soils together with the implementation effective remediation technologies to minimize possible impacts on human health.

  17. Food safety and bioavailability evaluations of four vegetables grown in the highly arsenic-contaminated soils on the Guandu Plain of northern Taiwan.

    PubMed

    Su, Shaw-Wei; Tsui, Chun-Chih; Lai, Hung-Yu; Chen, Zueng-Sang

    2014-04-14

    Arsenic contamination in a large area of agricultural fields on the Guandu Plain of northern Taiwan was confirmed in a survey conducted in 2006, but research concerning the relationship between bioavailable As concentrations in contaminated soils and crop production in Taiwan is not available. Pot experiments were conducted to examine the growth and accumulation of As in four vegetable crops grown in As-contaminated soils and to assess As intake through consumption. The phytotoxic effects of As in soils were not shown in the pot experiments in which vegetable crops were grown in soils contaminated with different As levels in situ collected from Guandu Plain (120-460 mg/kg) or artificially spiked As-contaminated soils (50-170 mg/kg). Experimental results showed that the bioavailable As extracted with 0.5M NaHCO3 from soils can be used to estimate As concentrations in vegetables. The As concentrations in the vegetables were compared with data shown in the literature and As limits calculated from drinking water standards and the provisional tolerance weekly intake (PTWI) of inorganic As established by the Food and Agriculture Organization of the United Nations/World Health Organization (FAO/WHO). Although the As levels in the vegetables were not high and the bioavailability of As in the soils was quite low, long-term consumption may result in higher As intake in the human body.

  18. Concentrations of lead, cadmium and barium in urban garden-grown vegetables: the impact of soil variables

    PubMed Central

    McBride, Murray B.; Shayler, Hannah A.; Spliethoff, Henry M.; Mitchell, Rebecca G.; Marquez-Bravo, Lydia G.; Ferenz, Gretchen S.; Russell-Anelli, Jonathan M.; Casey, Linda; Bachman, Sharon

    2014-01-01

    Paired vegetable/soil samples from New York City and Buffalo, NY, gardens were analyzed for lead (Pb), cadmium (Cd) and barium (Ba). Vegetable aluminum (Al) was measured to assess soil adherence. Soil and vegetable metal concentrations did not correlate; vegetable concentrations varied by crop type. Pb was below health-based guidance values (EU standards) in virtually all fruits. 47% of root crops and 9% of leafy greens exceeded guidance values; over half the vegetables exceeded the 95th percentile of market-basket concentrations for Pb. Vegetable Pb correlated with Al; soil particle adherence/incorporation was more important than Pb uptake via roots. Cd was similar to market-basket concentrations and below guidance values in nearly all samples. Vegetable Ba was much higher than Pb or Cd, although soil Ba was lower than soil Pb. The poor relationship between vegetable and soil metal concentrations is attributable to particulate contamination of vegetables and soil characteristics that influence phytoavailability. PMID:25163429

  19. Concentrations of lead, cadmium and barium in urban garden-grown vegetables: the impact of soil variables.

    PubMed

    McBride, Murray B; Shayler, Hannah A; Spliethoff, Henry M; Mitchell, Rebecca G; Marquez-Bravo, Lydia G; Ferenz, Gretchen S; Russell-Anelli, Jonathan M; Casey, Linda; Bachman, Sharon

    2014-11-01

    Paired vegetable/soil samples from New York City and Buffalo, NY, gardens were analyzed for lead (Pb), cadmium (Cd) and barium (Ba). Vegetable aluminum (Al) was measured to assess soil adherence. Soil and vegetable metal concentrations did not correlate; vegetable concentrations varied by crop type. Pb was below health-based guidance values (EU standards) in virtually all fruits. 47% of root crops and 9% of leafy greens exceeded guidance values; over half the vegetables exceeded the 95th percentile of market-basket concentrations for Pb. Vegetable Pb correlated with Al; soil particle adherence/incorporation was more important than Pb uptake via roots. Cd was similar to market-basket concentrations and below guidance values in nearly all samples. Vegetable Ba was much higher than Pb or Cd, although soil Ba was lower than soil Pb. The poor relationship between vegetable and soil metal concentrations is attributable to particulate contamination of vegetables and soil characteristics that influence phytoavailability.

  20. Residual behaviour of profenofos on some field-grown vegetables and its removal using various washing solutions and household processing.

    PubMed

    Radwan, M A; Abu-Elamayem, M M; Shiboob, M H; Abdel-Aal, A

    2005-04-01

    Profenofos (Selecron 72% EC), was sprayed on field-grown pepper and eggplant at the recommended rate of 1.28 kg a,i/ha. Fruit samples were collected at 1 h to 14 days after application and analysed to determine the content and dissipation rate of profenofos. The effect of different washing solutions and some household processing on the removal of such residues from treated vegetables were also investigated. Profenofos residues were quantified by using gas chromatography. The results showed that the consumable safety time were found to be 10 days on sweet pepper and 14 days on hot pepper and eggplant fruits. The initial disappearance of profenofos appeared to follow first order kinetics with different rates of reaction of 0.38, 0.40 and 0.35 day(-1) for hot pepper, sweet pepper and eggplant, respectively. The corresponding half-lives (t1/2) were 1.84, 1.74 and 1.96 days. Also, the results indicated that tap water, potassium permenganate and acetic acid solution gave high percent removal of profenofos residues from hot and sweet pepper fruits, while no detectable residues was found in eggplant fruit after washing with soap and acetic acid solutions. In general, all tested washing solutions gave higher percent removal of profenofos residues from eggplant fruit than the two other pepper fruits. Blanching and frying of pepper and eggplant fruits resulted in great reduction to almost completely removed (approximately 100%) of the deposited profenofos. In addition, pickling process removed 92.58 and 95.61% from hot pepper fruit after one week and after two weeks, respectively.

  1. Heavy metals health risk assessment for population via consumption of vegetables grown in old mining area; a case study: Banat County, Romania

    PubMed Central

    2011-01-01

    Background The aim of this study is to measure the levels of heavy metals (Fe, Mn, Zn, Cu, Ni, Cd and Pb) found in common vegetables (parsley, carrot, onion, lettuce, cucumber and green beans) grown in contaminated mining areas compared with those grown in reference clear area and to determine their potential detrimental effects via calculation of the daily metal intake (DImetal) and Target Hazard Quotients (THQ) for normal daily consumption of these vegetables, for male and female gender. Results Compared with the reference in contaminated areas, soil and plant contents of all analyzed metals are higher, usually over normally content for Mn, Zn, Cu, Cd and Pb. Particularly, in soil, higher values than intervention threshold values (ITV) were found for Cu and Pb and higher than maximum allowable limits (MAL) for Zn, Cu, Cd and Pb for parsley roots and leaves, carrot roots, cabbage, lettuce and cucumber. DImetal and THQ values for male and female were calculated for each vegetable and metal and for which oral reference doses exist. The combined THQ values calculated are concerning in that they are usually below the safe level of THQ<1 for all vegetables grown in reference area. In contaminated Moldova Noua (M) area the combined THQ exceeded the safe level only for parsley roots, while in more contaminated Ruschita (R) area combined THQ exceeded the safe level for parsley and carrot roots, lettuce and cabbage. Cd and Pb, most toxic metals to humans, have an increasing prevalence in the combined THQ for leafy (cabbage and lettuce) and fruit vegetables (cucumber). In the root vegetables only Pb has an increasing prevalence in combined THQ values. In all areas female THQ is higher than male THQ. Conclusion The results of this study regarding metal contents in soils, vegetables, DImetal and THQ suggest that the consumption of some vegetables (especially parsley, carrot and cabbage and less for lettuce, cucumber and green beans) is not free of risks in these areas. The

  2. Passive-solar greenhouse

    SciTech Connect

    Not Available

    1982-01-01

    Our project objective was to design, construct, and operate a commercialized (16' x 50') passive, solar greenhouse. The structure was originally intended as a vegetable forcing facility to produce vegetable crops in the off-season. Building and size constraints and economic considerations convinced us to use the greenhouse for producing bedding plants and vegetable starts in the spring, high value vegetables (tomatoes, cucumbers) in the fall and forced bulbs in the winter. This crop sequence allows us to use the greenhouse all year without additional heat as the crops are adopted to the temperature regime of the greenhouse during each particular season. In our first season, the greenhouse performed beautifully. The lowest temperature recorded was 38/sup 0/F after 4 cold, cloudy days in February. The production of bedding plants has allowed us to diversify our products and the early transplants we produced were a great asset to our vegetable farming operation. Although construction cost (4.57 sq. ft.) is higher than that of a conventional polyethylene-covered, quonset-type greenhouse (approx. $1.92 sq. ft.), our annual operating cost is cheaper than that of a conventional greenhouse (0.49 cents sq. ft. versus 0.67 cents sq. ft.) due to a longer usable lifetime of the structure and the elimination of heating costs. Our structure has been toured by interested individuals, school and farm groups. We plan to publicize the structure and its advantages by promoting more visits to the site.

  3. Greenhouse Gas (CO2, CH4 & N2O) Feedbacks are Regulated by Phenological Changes in Herbivore-Vegetation Interactions in Alaskan Coastal Tundra

    NASA Astrophysics Data System (ADS)

    Kelsey, K.; Leffler, A. J.; Beard, K. H.; Lynoe, K. B.; Choi, R. T.; Welker, J. M.

    2016-12-01

    Changing phenology is a central component of climate change in northern ecosystems. Phenological changes, such as advancement of the growing season, are particularly important in ecosystems that host long-distance migratory herbivores which alter local biogeochemical cycling through grazing, trampling and defecation, and have important effects on primary production and patterns of greenhouse gas fluxes. In the Yukon-Kuskokwim River Delta in western Alaska, such changes have created the potential for a `phenological mismatch' between the rapidly advancing growing season, and the timing of migration of ca. one million herbivorous geese to this region in the summer. Here we investigated the effects of this potential mismatch on greenhouse gas fluxes (CO2, CH4 and N2O) through a replicated factorial experiment in which we manipulated the onset of the growing season (advanced vs. ambient) and timing of grazing (early, typical, late or none). Our plot-scale measurements indicated that grazed coastal tundra was a small sink of CO2 during the growing season ( 4 µmol m-2 s-1). CH4 emissions were higher in the early season ( 20-80 nmols m-2 s-1) than later in the growing season ( 0-40 nmols m-2 s-1) and N2O emissions were consistently below 1 nmol m-2 s-1. Both advancing the growing season and delaying the timing of grazing increased net CO2 uptake. Unlike CO2 exchange, CH4 emissions were driven by small-scale heterogeneity in vegetation more than advanced growing season and timing of grazing, and N2O emissions were negligible under all treatments. These results indicate that while an advancing growing season and a delay in the timing of goose grazing may increase the growing season C sink strength of these grazed systems, CH4 emissions, which are also sizeable, are not driven by phenological changes, making the future overall greenhouse gas forcing of this region difficult to anticipate.

  4. Hazardous impact and translocation of vanadium (V) species from soil to different vegetables and grasses grown in the vicinity of thermal power plant.

    PubMed

    Khan, Sumaira; Kazi, Tasneem Gul; Kolachi, Nida Fatima; Baig, Jameel Ahmed; Afridi, Hassan Imran; Shah, Abdul Qadir; Kumar, Sham; Shah, Faheem

    2011-06-15

    The distribution of vanadium (V) species in soil (test soil), vegetables and grasses, collected from the vicinity of a thermal power plant has been studied. For comparison purpose soil (control soil), same vegetable and grass samples were collected from agricultural land devoid of any industrial area. A simple and efficient ultrasonic assisted extraction method has been developed for the extraction of V(5+) species from soil, vegetable and grass samples using Na(2)CO(3) in the range of 0.1-0.5 mol/L. For comparison purpose same sub samples were also extracted by conventional heating method. The total and V species were determined by electrothermal atomic absorption spectrometry using different modifiers. The validity of V(5+) and V(4+) determination had been confirmed by the spike recovery and total amount of V by the analysis of CRM 1570 (spinach leave) and sub samples of agricultural soil. The concentration of total V was found in the range of 90-215 and 11.4-42.3 μg/g in test and control soil samples, respectively. The contents of V(5+) and total V in vegetables and grasses grown around the thermal power plant were found in the range of 2.9-5.25 and 8.74-14.9 μg/g, respectively, which were significantly higher than those values obtained from vegetables and fodders grown in non exposed agricultural site (P<0.01). Statistical evaluations indicate that the sum of concentrations of V(5+) and V(4+) species was not significantly different from total concentration of V in same sub samples of vegetable, grass and soil of both origins, at 95% level of confidence.

  5. Greenhouse Gases

    MedlinePlus

    ... and the Environment Greenhouse Gases Effect on the Climate Where Greenhouse Gases Come From Outlook for Future ... greenhouse effect that results in global warming and climate change. Many gases exhibit these greenhouse properties. Some ...

  6. The impact of exogenous N supply on soluble organic nitrogen dynamics and nitrogen balance in a greenhouse vegetable system.

    PubMed

    Liang, Bin; Kang, Lingyun; Ren, Tao; Junliang, Li; Chen, Qing; Wang, Jingguo

    2015-05-01

    A long-term greenhouse experiment (2004-2012) was conducted with continuous tomato (Lycopersicum esculentum Mill.) plantings to understand the influence of an exogenous nitrogen supply from irrigation water, chemical fertilizer, or organic amendment on the N balance and soluble organic nitrogen (SON). The results from 16 tomato growing seasons indicated that the application of organic amendment (manure and straw) alone (Or-N) resulted in the same yield as the conventional chemical N with organic amendment (Co-N) and the reduced chemical N with organic amendment (Re-N) treatments. The annual apparent N loss was >1000 and 438 kg N ha(-1) in the Co-N and Re-N treatments, respectively. Over the study period, the SON in the 1.8 m soil profile was 1449 and 1978 kg N ha(-1) in the Re-N and Co-N treatments, respectively, it was 1.7- and 2.3-fold higher than that observed in the Or-N treatment, which indicated that SON increased with the chemical N application. The percentage of SON in the cumulative soluble N (SON plus mineral N) ranged from 28% to 44%, and there were no significant differences across the 0-0.6, 0.6-1.2, and 1.2-1.8 m soil profile, which indicated that the leaching and distribution of SON was similar to those of the mineral N in the 0-1.8 m soil profile. We conclude that the mobility of soluble organic N in the 0-1.8 m of the soil was synchronous with the mineral N under a greenhouse production system, and the risk of soluble organic N leaching increased with inorganic N application rate. Therefore, leaching of SON in the intensive agriculture should not be ignored when evaluating the risk of N leaching.

  7. Attempts to reduce exposure to fungi, β-glucan, bacteria, endotoxin and dust in vegetable greenhouses and a packaging unit.

    PubMed

    Madsen, Anne Mette; Tendal, Kira; Frederiksen, Margit W

    2014-01-15

    Indoor handling of large amounts of plant materials occurs in different occupational settings including greenhouses and causes exposure to bioaerosols. The bioaerosol components fungi, β-glucan, bacteria and endotoxin are involved in different airway symptoms and health effects can be dose-dependent. Therefore, there is a persistent need to reduce exposure. The aims of this study were to identify tasks causing exposure and to evaluate preventive measures aimed at reducing exposure of greenhouse workers to bioaerosols, and to study factors affecting the exposure. We have focused on different exposure scenarios; one with high short-term exposure found during clearing of old cucumber plants; the other with long-term, mid-level exposure found during tomato picking, leaf nipping, stringing up tomato plants, and packaging of cucumbers. Clearing of non-dried cucumber plants compared with clearing of dried cucumber plants significantly reduced the exposure to dust, endotoxin, bacteria, fungal spores and β-glucan. More endotoxin and fungi are emitted and more of the emitted particles were of respirable size if the leaves were dried. Along the cucumber packaging line, exposure levels were highly specific to each personal subtask. The subtask 'unloading of cucumbers' was the source of exposure making task ventilation or shielding of the process a possibility. Elimination of leaf debris on the floor reduced the exposure to fungi significantly. However, leaf debris on the floor did not contribute significantly to the exposure to dust, endotoxin and bacteria. Furthermore, to eliminate leaf debris, it had to be cleared away and this was associated with a higher exposure to dust and endotoxin. The age of the plants affected the exposure level to bioaerosols with higher exposures from old plants. In conclusion, different tasks and subtasks cause very different exposure levels. It is possible to reduce exposure by identifying subtasks causing the exposure and by modifying work

  8. Accumulation and potential health risks of cadmium, lead and arsenic in vegetables grown near mining sites in Northern Vietnam.

    PubMed

    Bui, Anh T K; Nguyen, Ha T H; Nguyen, Minh N; Tran, Tuyet-Hanh T; Vu, Toan V; Nguyen, Chuyen H; Reynolds, Heather L

    2016-09-01

    The effect of environmental pollution on the safety of vegetable crops is a serious global public health issue. This study was conducted to assess heavy metal concentrations in soil, irrigation water, and 21 local vegetable species collected from four sites near mining activities and one control site in Northern Vietnam. Soils from vegetable fields in the mining areas were contaminated with cadmium (Cd), lead (Pb), and arsenic (As), while irrigation water was contaminated with Pb. Average concentrations of Pb and As in fresh vegetable samples collected at the four mining sites exceeded maximum levels (MLs) set by international food standards for Pb (70.6 % of vegetable samples) and As (44.1 % of vegetable samples), while average Cd concentrations in vegetables at all sites were below the MLs of 0.2. The average total target hazard quotient (TTHQ) across all vegetable species sampled was higher than the safety threshold of 1.0, indicating a health risk. Based on the weight of evidence, we find that cultivation of vegetables in the studied mining sites is an important risk contributor for local residents' health.

  9. Health risk assessment of polycyclic aromatic hydrocarbons and heavy metals via dietary intake of vegetables grown in the vicinity of thermal power plants.

    PubMed

    Khillare, P S; Jyethi, Darpa Saurav; Sarkar, Sayantan

    2012-05-01

    Six different vegetables grown in the vicinity of three thermal power plants and a background site in Delhi, India were analyzed for 16 priority polycyclic aromatic hydrocarbons (PAHs) and 7 heavy metals (Cd, Cu, Cr, Ni, Zn, Fe and Mn). Annual mean concentrations of PAHs and all metals were found to be significantly higher (ANOVA, p<0.001) at power plant sites as compared to the background site. Higher abundances of coal tracer PAHs such as Phen, Anth, Flan, Pyr and Chry in power plant vegetables suggested possible impacts of coal combustion emissions. Higher ratios of polluted sample-to-background sample of vegetables were found especially for Cr, Cd, Ni and Zn. Spinach and radish showed greater accumulation of PAHs and metals on a mass basis at the power plant sites while vegetables belonging to the gourd family showed highest relative enrichment. Power plant samples showed 184-475% greater metal pollution index (MPI) values as compared to the background location while health risk indices (HRI) for Cd and Ni exceeded the safe limit for most vegetables. Incremental lifetime cancer risk (ILCR) assessment showed that up to 58 excess cancer cases are likely in Delhi for lifetime ingestion exposure to PAHs at their observed concentrations.

  10. [Contamination and health risk for heavy metals via consumption of vegetables grown in fragmentary vegetable plots from a typical nonferrous metals mine city].

    PubMed

    Li, Ru-Zhong; Pan, Cheng-Rong; Xu, Jing-Jing; Chen, Jing; Jiang, Yan-Min

    2013-03-01

    A systematic survey of As, Ni, Cu, Pb, Cd and Zn concentrations in eight kinds of vegetables (involving 226 samples) and their corresponding soils at 35 sampling sites in the fragmentary vegetable plots of a typical nonferrous metals mine city, Tongling, was carried out for assessing heavy metal pollution, bio-accumulation ability and potential health risk to local inhabitants due to exposure via consumption of vegetables. The results showed that: (1) The soils of the studied vegetable plots were seriously contaminated by heavy metals and the mean concentrations of As, Ni, Cu, Pb, Cd and Zn reached 96.96, 56.64, 1 247.82, 313.59, 6.743 and 600.96 mg x kg(-1), respectively, all significantly exceeding the soil background value of Tongling city; (2) The mean values of integrated pollution index corresponding to eight varieties of vegetables were all higher than the threshold value (i. e. 3.0) of heavy pollution; (3) In general, the largest bioaccumulation factor of heavy metals in vegetables was As, followed by Ni and Cu, and the order of pollution degree of heavy metals in vegetables was Ni > Zn > Cu > Pb > As > Cd; (4) The target hazard quotients (THQs) of As, Ni, Cu, Pb, Cd and Zn were 17.92, 1.01, 10.14, 0.73, 0.21 and 1.93, respectively. Arsenic and copper were the major risk contributors for inhabitants since the THQs of them respectively mounted to 56.10% and 31.75% of the total THQ value according to the average vegetable consumption; (5) The estimated daily intake (DI) of As, Ni, Cu, Pb, Cd and Zn from vegetables was 324.38, 1 211.25, 24 326.25, 176.25, 12.75 and 34 800 microg x d(-1) for adult residents, respectively; and (6) The target cancer risk (TR) of vegetables polluted by As to individual human health was 8.06 x 10(-3), significantly higher than the management standard (i. e. 10(-6) - 10(-4)) of United States Environmental Protection Agency (US EPA) and the standard (i. e. 5.0 x 10(-5)) of International Commission on Radiological Protection (ICRP

  11. Measuring calcium, potassium, and nitrate in plant nutrient solutions using ion-selective electrodes in hydroponic greenhouse of some vegetables.

    PubMed

    Vardar, Gökay; Altıkatoğlu, Melda; Ortaç, Deniz; Cemek, Mustafa; Işıldak, İbrahim

    2015-01-01

    Generally, the life cycle of plants depends on the uptake of essential nutrients in a balanced manner and on toxic elements being under a certain concentration. Lack of control of nutrient levels in nutrient solution can result in reduced plant growth and undesired conditions such as blossom-end rot. In this study, sensitivity and selectivity tests for various polyvinylchloride (PVC)-based ion-selective membranes were conducted to identify those suitable for measuring typical concentration ranges of macronutrients, that is, NO(3-), K(+), and Ca(2+), in hydroponic solutions. The sensitivity and selectivity of PVC-membrane-based ion-selective sensors prepared with tetradodecylammoniumnitrate for NO(3-), valinomycin for K(+), and Ca ionophore IV for Ca(2+) were found to be satisfactory for measuring NO(3-), K(+), and Ca(2+) ions in nutrient solutions over typical ranges of hydroponic concentrations. Potassium, calcium, and nitrate levels that were utilized by cucumber and tomato seedlings in the greenhouse were different. The findings show that tomato plants consumed less amounts of nitrate than cucumber plants over the first 2 months of their growth. We also found that the potassium intake was higher than other nutritional elements tested for all plants.

  12. Effects of vegetation structure on soil carbon, nutrients and greenhouse gas exchange in a savannah ecosystem of Mount Kilimanjaro Region

    NASA Astrophysics Data System (ADS)

    Becker, J.

    2015-12-01

    The savannah biome is a hotspot for biodiversity and wildlife conservation in Africa and recently got in the focus of research on carbon sequestration. Savannah ecosystems are under strong pressure from climate and land-use change, especially around populous areas like the Mt. Kilimanjaro region. Savannah vegetation consists of grassland with isolated trees and is therefore characterized by high spatial variation of canopy cover, aboveground biomass and root structure. The canopy structure is a major regulator for soil ecological parameters and soil-atmospheric trace gas exchange (CO2, N2O, CH4) in water limited environments. The spatial distribution of these parameters and the connection between above and belowground processes are important to understand and predict ecosystem changes and estimate its vulnerability. Our objective was to determine spatial trends and changes of soil parameters and relate their variability to the vegetation structure. We chose three trees from each of the two most dominant species (Acacia nilotica and Balanites aegyptiaca) in our research area. For each tree, we selected transects with nine sampling points of the same relative distances to the stem. At these each sampling point a soil core was taken and separated in 0-10 cm and 10-30 cm depth. We measured soil carbon (C) and nitrogen (N) storage, microbial biomass C and N, Natural δ13C, soil respiration, available nutrients, pH, cation exchange capacity (CEC) as well as root biomass and -density, soil temperature and soil water content. Concentrations and stocks of C and N fractions, CEC and K+ decreased up to 50% outside the crown covered area. Microbial C:N ratio and CO2 efflux was about 30% higher outside the crown. This indicates N limitation and low C use efficiency in soil outside the crown area. We conclude that the spatial structure of aboveground biomass in savanna ecosystems leads to a spatial variance in nutrient limitation. Therefore, the capability of a savanna ecosystem

  13. Lead/cadmium contamination and lead isotopic ratios in vegetables grown in peri-urban and mining/smelting contaminated sites in Nanjing, China.

    PubMed

    Hu, Xin; Ding, Zhuhong

    2009-01-01

    Lead/cadmium contamination in vegetables grown in peri-urban area of Nanjing, China was assessed and the route for metals entering into plants was investigated through lead isotopic tracing. Results show that agricultural soils have been polluted with Cd. Contents of Pb (22.1-37.5 mg kg(-1 )dw) and Cd (2.53-4.19 mg kg(-1) dw) in vegetables' edible parts nearby a lead/zinc mining/smelting plant were beyond their maximum allowable limit prescribed in the (EC) No 1881/2006. Pb isotope ratios in plants differed from those in the corresponding soils, suggesting that soils were not the only contamination source of Pb and Cd in plants.

  14. Reduction of lead concentrations in vegetables grown in Tarragona Province, Spain, as a consequence of reduction of lead in gasoline

    SciTech Connect

    Belles, M.; Rico, A.; Schuhmacher, M.

    1995-12-31

    Lead concentrations were determined in 350 samples belonging to 13 different species of vegetables from Tarragona Province, Spain. The samples were subjected to lead analyses by graphite furnace atomic absorption spectrophotometry. During the period 1989-1994, an average decrease for lead concentrations of 69% was estimated. Spinach showed the lowest reduction2 in lead content (6%), while the highest decreases were observed for onion (87%) and leek (90%). Taking into account the average consumption of vegetable foodstuffs by the population of Tarragona Province, the daily lead intake through edible vegetables was reduced from 41.5 {mu}g/d in 1989 to 10.6 {mu}g/d in 1994. The results of the current study demonstrate a substantial decline in the lead levels of vegetables from Tarragona Province. The major cause of this decline is most likely the reduced leaded gasoline consumption.

  15. Coliform Contamination of Peri-urban Grown Vegetables and Potential Public Health Risks: Evidence from Kumasi, Ghana.

    PubMed

    Abass, Kabila; Ganle, John Kuumuori; Adaborna, Eric

    2016-04-01

    Peri-urban vegetable farming in Ghana is an important livelihood activity for an increasing number of people. However, increasing quality and public health concerns have been raised, partly because freshwater availability for irrigation purposes is a major constraint. This paper investigated on-farm vegetable contamination and potential health risks using samples of lettuce, spring onions and cabbage randomly selected from 18 vegetable farms in peri-urban Kumasi, Ghana. Vegetable samples were tested for total coliform, fecal coliform, Escherichia coli and Salmonella spp. bacteria contamination using the Most Probable Number method. Results show high contamination levels of total and fecal coliforms, and Escherichia coli bacteria in all 18 vegetable samples. The mean total coliform/100 ml concentration for spring onions, lettuce and cabbage were 9.15 × 10(9), 4.7 × 10(7) and 8.3 × 10(7) respectively. The mean fecal coliform concentration for spring onions, lettuce and cabbage were also 1.5 × 10(8), 4.15 × 10(7) and 2.15 × 10(7) respectively, while the mean Escherichia coli bacteria contamination for spring onions, lettuce and cabbage were 1.4 × 10(8), 2.2 × 10(7) and 3.2 × 10(7) respectively. The level of total coliform, fecal coliform and Escherichia coli bacteria contamination in all the vegetable samples however declined as the distance between the main water source (Wiwi River) and farms increases. Nonetheless, all contamination levels were well above acceptable standards, and could therefore pose serious public health risks to consumers. Increased education and supervision of farmers, as well as public health and food hygiene education of consumers, are critical to reducing on-farm vegetable contamination and the health risks associated with consumption of such vegetables.

  16. Plant Growth-Promoting Rhizobacteria Inoculation to Enhance Vegetative Growth, Nitrogen Fixation and Nitrogen Remobilisation of Maize under Greenhouse Conditions

    PubMed Central

    Kuan, Khing Boon; Othman, Radziah; Abdul Rahim, Khairuddin; Shamsuddin, Zulkifli H.

    2016-01-01

    Plant growth-promoting rhizobacteria (PGPR) may provide a biological alternative to fix atmospheric N2 and delay N remobilisation in maize plant to increase crop yield, based on an understanding that plant-N remobilisation is directly correlated to its plant senescence. Thus, four PGPR strains were selected from a series of bacterial strains isolated from maize roots at two locations in Malaysia. The PGPR strains were screened in vitro for their biochemical plant growth-promoting (PGP) abilities and plant growth promotion assays. These strains were identified as Klebsiella sp. Br1, Klebsiella pneumoniae Fr1, Bacillus pumilus S1r1 and Acinetobacter sp. S3r2 and a reference strain used was Bacillus subtilis UPMB10. All the PGPR strains were tested positive for N2 fixation, phosphate solubilisation and auxin production by in vitro tests. In a greenhouse experiment with reduced fertiliser-N input (a third of recommended fertiliser-N rate), the N2 fixation abilities of PGPR in association with maize were determined by 15N isotope dilution technique at two harvests, namely, prior to anthesis (D50) and ear harvest (D65). The results indicated that dry biomass of top, root and ear, total N content and bacterial colonisations in non-rhizosphere, rhizosphere and endosphere of maize roots were influenced by PGPR inoculation. In particular, the plants inoculated with B. pumilus S1r1 generally outperformed those with the other treatments. They produced the highest N2 fixing capacity of 30.5% (262 mg N2 fixed plant−1) and 25.5% (304 mg N2 fixed plant−1) of the total N requirement of maize top at D50 and D65, respectively. N remobilisation and plant senescence in maize were delayed by PGPR inoculation, which is an indicative of greater grain production. This is indicated by significant interactions between PGPR strains and time of harvests for parameters on N uptake and at. % 15Ne of tassel. The phenomenon is also supported by the lower N content in tassels of maize treated

  17. Plant Growth-Promoting Rhizobacteria Inoculation to Enhance Vegetative Growth, Nitrogen Fixation and Nitrogen Remobilisation of Maize under Greenhouse Conditions.

    PubMed

    Kuan, Khing Boon; Othman, Radziah; Abdul Rahim, Khairuddin; Shamsuddin, Zulkifli H

    2016-01-01

    Plant growth-promoting rhizobacteria (PGPR) may provide a biological alternative to fix atmospheric N2 and delay N remobilisation in maize plant to increase crop yield, based on an understanding that plant-N remobilisation is directly correlated to its plant senescence. Thus, four PGPR strains were selected from a series of bacterial strains isolated from maize roots at two locations in Malaysia. The PGPR strains were screened in vitro for their biochemical plant growth-promoting (PGP) abilities and plant growth promotion assays. These strains were identified as Klebsiella sp. Br1, Klebsiella pneumoniae Fr1, Bacillus pumilus S1r1 and Acinetobacter sp. S3r2 and a reference strain used was Bacillus subtilis UPMB10. All the PGPR strains were tested positive for N2 fixation, phosphate solubilisation and auxin production by in vitro tests. In a greenhouse experiment with reduced fertiliser-N input (a third of recommended fertiliser-N rate), the N2 fixation abilities of PGPR in association with maize were determined by 15N isotope dilution technique at two harvests, namely, prior to anthesis (D50) and ear harvest (D65). The results indicated that dry biomass of top, root and ear, total N content and bacterial colonisations in non-rhizosphere, rhizosphere and endosphere of maize roots were influenced by PGPR inoculation. In particular, the plants inoculated with B. pumilus S1r1 generally outperformed those with the other treatments. They produced the highest N2 fixing capacity of 30.5% (262 mg N2 fixed plant-1) and 25.5% (304 mg N2 fixed plant-1) of the total N requirement of maize top at D50 and D65, respectively. N remobilisation and plant senescence in maize were delayed by PGPR inoculation, which is an indicative of greater grain production. This is indicated by significant interactions between PGPR strains and time of harvests for parameters on N uptake and at. % 15Ne of tassel. The phenomenon is also supported by the lower N content in tassels of maize treated with

  18. Salmonella enterica Serovar Typhimurium and Escherichia coli Contamination of Root and Leaf Vegetables Grown in Soils with Incorporated Bovine Manure

    PubMed Central

    Natvig, Erin E.; Ingham, Steven C.; Ingham, Barbara H.; Cooperband, Leslie R.; Roper, Teryl R.

    2002-01-01

    Bovine manure, with or without added Salmonella enterica serovar Typhimurium (three strains), was incorporated into silty clay loam (SCL) and loamy sand (LS) soil beds (53- by 114-cm surface area, 17.5 cm deep) and maintained in two controlled-environment chambers. The S. enterica serovar Typhimurium inoculum was 4 to 5 log CFU/g in manure-fertilized soil. The conditions in the two environmental chambers, each containing inoculated and uninoculated beds of manure-fertilized soil, simulated daily average Madison, Wis., weather conditions (hourly temperatures, rainfall, daylight, and humidity) for a 1 March or a 1 June manure application and subsequent vegetable growing seasons ending 9 August or 28 September, respectively. Core soil samples were taken biweekly from both inoculated and uninoculated soil beds in each chamber. Radishes, arugula, and carrots were planted in soil beds, thinned, and harvested. Soils, thinned vegetables, and harvested vegetables were analyzed for S. enterica serovar Typhimurium and Escherichia coli (indigenous in manure). After the 1 March manure application, S. enterica serovar Typhimurium was detected at low levels in both soils on 31 May, but not on vegetables planted 1 May and harvested 12 July from either soil. After the 1 June manure application, S. enterica serovar Typhimurium was detected in SCL soil on 7 September and on radishes and arugula planted in SCL soil on 15 August and harvested on 27 September. In LS soil, S. enterica serovar Typhimurium died at a similar rate (P ≥ 0.05) after the 1 June manure application and was less often detected on arugula and radishes harvested from this soil compared to the SCL soil. Pathogen levels on vegetables were decreased by washing. Manure application in cool (daily average maximum temperature of <10°C) spring conditions is recommended to ensure that harvested vegetables are not contaminated with S. enterica serovar Typhimurium. Manure application under warmer (daily average maximum

  19. Effect of a full-grown vegetative filter strip on herbicide runoff: maintaining of filter capacity over time.

    PubMed

    Otto, S; Vianello, M; Infantino, A; Zanin, G; Di Guardo, A

    2008-03-01

    Narrow vegetative filter strips (VFS) proved to effectively reduce herbicide runoff from cultivated fields mainly due to the ability of vegetation to delay surface runoff, promote infiltration and adsorb herbicides. Since VFS are dynamic systems, their performance would not remain constant over the years indicating the need to define suitable buffer management. In order to evaluate the performance of different five and six year-old VFS, the runoff of the herbicides metolachlor and terbuthylazine was monitored in 2002 and 2003 in an experimental site in northern Italy. The structure of the herbaceous cover in the buffers changes over time. When rows of trees are present, the grass cover is decreased by the shading action of the trees, but the leaf litter gains importance. In VFS with grass cover only, the cover composition changes because of the substitution of grass by broadleaf species. Six metres wide VFS are very effective in reducing runoff volume and concentration during both wet and dry years. Classification analysis showed that runoff concentration and volume are linked to the characteristics of the rainfall event, buffer, source of herbicides and time after application. Regression analysis showed that the significant predictors for runoff volume are rainfall amount and intensity, total vegetal cover in the VFS, crop leaf area index and time after treatment; for concentration they are rainfall intensity, crop leaf area index and total vegetal cover in the VFS. The role of VFS is complex, so appropriate management is required to maintain its increasing filtering capacity over time.

  20. Bioaccumulation and cancer risk of polycyclic aromatic hydrocarbons in leafy vegetables grown in soils within automobile repair complex and environ in Uyo, Nigeria.

    PubMed

    Inam, Edu; Ibanga, Felicia; Essien, Joseph

    2016-12-01

    Using gas chromatography-mass spectrometry and an incremental lifetime cancer risks (ILCRs) assessment model, the bioaccumulation and cancer risk of 16 USEPA priority polycyclic aromatic hydrocarbons (PAHs) in leafy vegetables (Vernonia amygdalina and Lasianthera africanum) grown in soils within an automobile repair complex environment in Uyo, Nigeria was studied. The total PAHs concentrations recorded for soils ranged from 0.02 to 1.77 mg/kg. The highest level of 1.77 mg/kg was recorded for soils from the main automobile repair complex (site 1). Low molecular weight (LMW) PAHs were predominant although some high molecular weight (HMW) PAHs suites (0.04 mg/kg of chrysene and 0.04 of benzo[k]fluoranthene) were also found in site 1. The leafy vegetables accumulated PAHs were mostly LMW. Accumulation levels were similar but the extent of PAH uptake in vegetables was species dependent as V. amygdalina accumulated more (0.81 mg/kg). The bioaccumulation factors (BaFs) calculated ranged from 0.22 to 0.63 for L. africanum, and 0.18 to 0.55 for V. amygdalina in site 1 where high PAH levels were recorded in soil. Pearson correlation coefficient analysis revealed a strong positive relation between the PAH content of soil and the amount accumulated by L. africanum (r = 0.5) and V. amygdalina (r = 0.8) at p = 0.05. The vegetable's potential to bioaccumulate PAHs is indicative of their use as good bioindicators for PAH contamination in soil. Only two of the USEPA possible human carcinogenic PAHs were detected, and carcinogenic risk assessment based on occupational exposures to soil particles by adults revealed that the total risk level (7.17 × 10(-5)) contribution from incidental soil ingestion, dermal contact, and soil particle dust inhalation slightly exceed the USEPA acceptable limits (< 1.00 × 10(-5)). There is a need for public education on consumption of vegetables grown in and around automobile repair complexes across Nigeria.

  1. The Greenhouse effect: impacts of ultraviolet-B (UV-B) radiation, carbon dioxide (CO2), and ozone (O3) on vegetation.

    PubMed

    Krupa, S V; Kickert, R N

    1989-01-01

    radiative cloud forcing. The effects of UV-B, CO2 and O3 on plants have been studied under growth chamber, greenhouse and field conditions. Few studies, if any, have examined the joint effects of more than one variable on plant response. There are methodological problems associated with many of these experiments. Thus, while results obtained from these studies can assist in our understanding, they must be viewed with caution in the context of the real world and predictions into the future. Biomass responses of plants to enhanced UV-B can be negative (adverse effect); positive (stimulatory effect) or no effect (tolerant). Sensitivity rankings have been developed for both crop and tree species. However, such rankings for UV-B do not consider dose-response curves. There are inconsistencies between the results obtained under controlled conditions versus field observations. Some of these inconsistencies appear due to the differences in responses between cultivars and varieties of a given plant species; and differences in the experimental methodology and protocol used. Nevertheless, based on the available literature, listings of sensitive crop and native plant species to UV-B are provided. Historically, plant biologists have studied the effects of CO2 on plants for many decades. Experiments have been performed under growth chamber, greenhouse and field conditions. Evidence is presented for various plant species in the form of relative yield increases due to CO2 enrichment. Sensitivity rankings (biomass response) are agein provided for crops and native plant species. However, most publications on the numerical analysis of cause-effect relationships do not consider sensitivity analysis of the mode used. Ozone is considered to be the most phytotoxic regional scale air pollutant. In the pre-occupation of loss in the O3 column, any increases in tropospheric O3 concentrations may be undermined relative to vegetation effects. As with the other stress factors, the effects of O3 have been

  2. Lipid formation and γ-linolenic acid production by Mucor circinelloides and Rhizopus sp., grown on vegetable oil

    PubMed Central

    Tauk-Tornisielo, Sâmia M.; Arasato, Luciana S.; de Almeida, Alex F.; Govone, José S.; Malagutti, Eleni N.

    2009-01-01

    The fungi strains were tested in Bioscreen automated system to select the best nutritional source. Following, shaking submserse cultures were studied in media containing sole carbon or nitrogen source. The growth of these strains improved in media containing vegetable oil, with high concentration of lipids. The high concentration of γ-linolenic acid was obtained with M. circinelloides in culture containing sesame oil. PMID:24031370

  3. [Greenhouse gases fluxes of biological soil crusts and soil ecosystem in the artificial sand-fixing vegetation region in Shapotou area].

    PubMed

    Hu, Yi-Gang; Feng, Yu-Lan; Zhang, Zhi-Shan; Huang, Lei; Zhang, Peng; Xu, Bing-Xin

    2014-01-01

    Uncertainties still existed for evaluating greenhouse gases fluxes (GHGs), including carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) at the regional scale for desert ecosystem because available GHGs data about biological soil crusts (BSCs) was very scarce. In 2011 and 2012, soil ecosystem covered by various types of BSCs and BSCs at different succession stages in an artificial sand-fixing vegetation region established in various periods at southeast of the Shapotou area in Tengger Desert was selected to measure fluxes of CO2, CH4 and N2O using static chamber and gas chromatography. The results showed that curst type, recovery time and their interactions with sampling date significantly affected CO2 flux. Recovery time and interaction of crust type and sampling date significantly affected CH4 flux. Sampling date significantly affected the fluxes of CO2, CH4 and N2O. The mean annual flux of CO2 for moss crust (105.1 mg x m(-2) x h(-1)) was significantly higher than that of algae crust (37.7 mg x m(-2) x h(-1)) at the same succession stage. Annual mean CH4 and N2O consumption was 19.9 and 3.4 microg x m(-2) x h(-1), respectively. Mean annual consumption of CH4 and N2O for algae crust was slightly higher than that of moss crust, however, significant difference was not found. Ecosystem respiration (Re) of desert soil covered by BSCs increased with the recovery process of desert ecosystem, in contrast, consumption of CH4 and N2O decreased. Re of moss crust was more sensitive to temperature and moisture variation than algae crust and Re sensitivity of temperature and moisture gradually increased with the development and succession of BSCs. Both soil temperature and moisture were not the main factor to determine CH4 and N2O fluxes of BSCs-soil in desert ecosystem.

  4. Establishment of an efficient and rapid method of multiple shoot regeneration and a comparative phenolics profile in in vitro and greenhouse-grown plants of psophocarpus tetragonolobus (L.) DC

    PubMed Central

    Singh, Vinayak; Chauhan, Namita Singh; Singh, Mohit; Idris, Asif; Madanala, Raju; Pande, Veena; Mohanty, Chandra Sekhar

    2014-01-01

    An in vitro method of multiple shoot induction and plant regeneration in Psophocarpus tetragonolobus (L.) DC was developed. Cotyledons, hypocotyls, epicotyls, internodal and young seedling leaves were used as explants. MS media supplemented with various concentrations of either thidiazuron (TDZ) or N6-benzylaminopurine (BAP) along with NAA or IAA combinations were used to determine their influence on multiple shoot induction. MS media supplemented with TDZ induced direct shoot regeneration when epicotyls and internodal segments were used as explants. TDZ at 3 mg L−1 induced highest rate (89.2 ± 3.28%) of regeneration with (13.4 ± 2.04) shoots per explant. MS media supplemented with BAP in combination with NAA or IAA induced callus mediated regeneration when cotyledons and hypocotyls were used as explants. BAP (2.5 mg L−1) and IAA (0.2 mg L−1) induced highest rate (100 ± 2.66%) of regeneration with (23.2 ± 2.66) shoots per explant. Mature plants produced from regenerated shoots were transferred successfully to the greenhouse. In a comparative study, the phenolics contents of various parts of greenhouse-grown plants with that of in vitro-raised plants showed significant variations. PMID:25482808

  5. [Irrigation scheduling with a 20 cm standard pan for drip-irrigated cucumber grown in solar greenhouse in the North China Plain].

    PubMed

    Gong, Xue-wen; Sun, Jing-sheng; Liu, Hao; Zhang, Hao; Wu, Xiao-lei; Sun, Yu-hong

    2015-11-01

    An experiment was conducted in 2013 and 2014 at the Xinxiang Comprehensive Experimental Station, Chinese Academy of Agriculture Sciences. Water amount was estimated with the Ep-20 and pan coefficient. Responses of cucumber evapotranspiration (ET), yield, quality and water use efficiency (WUE) to different drip irrigation amounts (Kcp1: 0.25; Kcp2: 0.5; Kcp3: 0.75; Kcp4: 1.0; Kcp5: 1.25) were investigated. The possibility of developing drip irrigation scheduling using the 20 cm pan was also discussed. Results showed that the seasonal evapotranspiration of cucumber ranged between 129 and 314 mm, and the water consumption generally increased with the increase in drip irrigation water amount. There was no significance difference in cucumber yield between the treatments with Kcp > 0.75, and the responses of mean fruit mass, number and length to water amount had a threshold value (0.75Ep-20). Regarding the fruit quality, the contents of total soluble solids, vitamin C and soluble sugar slightly decreased with increasing the irrigation water amount, while the soluble protein content varied in order as: Kcp2 > Kcp3 > Kcp4 > Kcp1 > Kcp5. There was a significant positive correlation (P < 0.01) between the pan evaporation and the reference crop evapotranspiration estimated based on a modified Penman-Monteith equation. In a conclusion, the drip water amount calculated with Kcp of 0.75 and the 20 cm pan were easy and feasible for cucumber cultivation in solar greenhouse in the North China Plain.

  6. Browns Ferry waste heat greenhouse. Progress report. Circular Z-117

    SciTech Connect

    Burns, E.R.; Carter, J.; Pile, R.S.; Roetheli, J.C.

    1980-08-01

    A 25,000-ft/sup 2/ experimental greenhouse at Browns Ferry Nuclear Plant was divided into three sections to compare two heat exchange systems using waste heat in condenser cooling water (CCW) with a conventionally heated zone. A 125-hp pump at each of the three power plant units provides a 3000 gal/min pumping capacity for the CCW which is pumped about 2000 ft through a 12-in. pipe to the greenhouse. Construction was completed in November 1978; initial engineering tests were not conducted on system performance until January 1979; and the first tomato crop was planted January 10, 1979. Harvest was completed in July 1979; and cucumbers, chrysanthemums, poinsettias, and gloxinias were grown during the following summer and fall. Low winter greenhouse temperatures reduced the yield and quality of tomatoes in the two waste heat sections which averaged 13.0 lbs/plant. The conventionally heated zone produced 15.4 lbs/plant. In January and February, temperatures of the CCW were sometimes as low as 52/sup 0/F, or 18/sup 0/F below the predicted 70/sup 0/F which was the minimum simulated CCW temperature used to develop the pilot greenhouse heating system at Muscle Shoals. The two heat exchange systems using CCW performed near design expectations - keeping the greenhouse air temperature within 10/sup 0/ to 12/sup 0/F of the incoming water temperature. Summer and fall production of cucumbers and ornamental crops was successful in all three sections, which were conventionally cooled. Production budgets indicated a greater potential for ornamental production than vegetable production in waste heat greenhouses. Economic studies showed that heat exchange systems using waste heat from CCW will require higher capital investment and greater electrical consumption than a conventionally heated greenhouse. However, depending upon the costs charged for CCW, the waste heat systems may show potential economic advantages as a result of reduced heating costs.

  7. Free amino acid and phenolic contents and antioxidative and cancer cell-inhibiting activities of extracts of 11 greenhouse-grown tomato varieties and 13 tomato-based foods.

    PubMed

    Choi, Suk-Hyun; Kim, Hyen-Ryung; Kim, Hyun-Jeong; Lee, In-Seon; Kozukue, Nobuyuki; Levin, Carol E; Friedman, Mendel

    2011-12-28

    Tomato (Solanum lycopersicum) plants synthesize nutrients, pigments, and bioactive compounds that benefit nutrition and human health. The nature and concentrations of these compounds are strongly influenced by varietal factors such as size and color as well as by processing. To better understand how these factors affect the concentration of nutrients and bioactive compounds, we analyzed 11 Korean tomato varieties grown under the same greenhouse conditions and 13 processed commercial tomato products for free amino acids and amino acid metabolites by HPLC, for individual phenolics by HPLC-MS, for total phenolics by the Folin-Ciocalteu method, for antioxidative activity by the FRAP and DPPH methods, and for cancer cell-inhibiting effects by the MTT assay. We also determined the protein content of the tomatoes by an automated Kjeldahl method. The results show that there is a broad range of bioactive compounds across tomato varieties and products. Small tomatoes had higher contents of bioactive compounds than the large ones. The content of phenolic compounds of processed products was lower than that of fresh tomatoes. Tomato extracts promoted growth in normal liver (Chang) cells, had little effect in normal lung (Hel299) cells, mildly inhibited growth of lung cancer (A549) cells, and first promoted and then, at higher concentrations, inhibited growth in lymphoma (U937) cells. The relationship of cell growth to measured constituents was not apparent. Dietary and health aspects of the results are discussed.

  8. Effects of air pollution on plant-insect interactions: increased susceptibility of greenhouse-grown soybeans to the Mexican bean beetle after plant exposure to SO/sub 2/

    SciTech Connect

    Hughes, P.R.; Potter, J.E.; Weinstein, L.H.

    1982-02-01

    Foliage from greenhouse-grown soybeans fumigated with 524 ..mu..g m/sup -3/ of SO/sub 2/ or from control plants held under the same conditions without fumigation was fed to Mexican bean beetle larvae and adults. The larvae developed faster and grew larger when fed on the fumigated leaves; larval mortality was consistently low and showed no apparent relationship to the type of leaves used as the food source. Adult females showed a significant feeding preference for discs cut from fumigated leaves and were more fecund when fed on the treated foliage than when fed on control leaves. A greater percentage of the females laid eggs, and the viability of the eggs was higher when the females were fed on fumigated leaves. These females produced more eggs per individual, with significant increases in both the number of eggs per mass and the number of masses per female. The longevity of egg-laying females did not differ significantly between the treatments.

  9. Effects of air pollution on plant-insect interactions: increased susceptibility of greenhouse-grown soybeans to the Mexican bean beetle after plant exposure to SO/sub 2/

    SciTech Connect

    Hughes, P.R.; Potter, J.E.; Weinstein, L.H.

    1982-02-15

    Foliage from greenhouse-grown soybeans fumigated with 524 ..mu..g.m/sup -3/ of SO/sub 2/ or from control plants held under the same conditions without fumigation was fed to Mexican bean beetle larvae and adults. The larvae developed faster and grew larger when fed on the fumigated leaves; larva mortality was consistently low and showed no apparent relationship to the type of leaves used as the food source. Adult females showed a significant feeding preference for discs cut from fumigated leaves and were more fecund when fed on the treated foliage than when fed on control leaves. A greater percentage of the females laid eggs, and the viability of the eggs was higher when the females were fed on fumigated leaves. These females produced more eggs per individual, with significant increases in both the number of eggs per mass and the number of masses per female. The longevity of egg-laying females did not differ significantly between the treatments.

  10. A geographical assessment of vegetation carbon stocks and greenhouse gas emissions on potential microalgae-based biofuel facilities in the United States.

    PubMed

    Quiroz Arita, Carlos; Yilmaz, Özge; Barlak, Semin; Catton, Kimberly B; Quinn, Jason C; Bradley, Thomas H

    2016-12-01

    The microalgae biofuels life cycle assessments (LCA) present in the literature have excluded the effects of direct land use change (DLUC) from facility construction under the assumption that DLUC effects are negligible. This study seeks to model the greenhouse gas (GHG) emissions of microalgae biofuels including DLUC by quantifying the CO2 equivalence of carbon released to the atmosphere through the construction of microalgae facilities. The locations and types of biomass and Soil Organic Carbon that are disturbed through microalgae cultivation facility construction are quantified using geographical models of microalgae productivity potential including consideration of land availability. The results of this study demonstrate that previous LCA of microalgae to biofuel processes have overestimated GHG benefits of microalgae-based biofuels production by failing to include the effect of DLUC. Previous estimations of microalgae biofuel production potential have correspondingly overestimated the volume of biofuels that can be produced in compliance with U.S. environmental goals. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Use of an in vitro digestion method to estimate human bioaccessibility of Cd in vegetables grown in smelter-impacted soils: the influence of cooking.

    PubMed

    Pelfrêne, Aurélie; Waterlot, Christophe; Guerin, Annie; Proix, Nicolas; Richard, Antoine; Douay, Francis

    2015-08-01

    Metal contamination of urban soils and homegrown vegetables has caused major concern. Some studies showed that cadmium (Cd) was among the most significant hazards in kitchen garden soils and prolonged exposure to this metal could cause deleterious health effects in humans. In general, most risk assessment procedures are based on total concentrations of metals in vegetables. The present study assesses human bioaccessibility of Cd in vegetables cultivated in smelter-impacted kitchen garden soils. Seven vegetables (radish, lettuce, French bean, carrot, leek, tomato, and potato) were considered. Using the UBM protocol (unified BARGE bioaccessibility method), the bioaccessibility of Cd was measured in raw/cooked vegetables. A considerable amount of Cd was mobilized from raw vegetables during the digestion process (on average 85% in the gastric phase and 69% in the gastrointestinal phase), which could be attributed to a high uptake of Cd during the growth of the vegetables. Most Cd is accumulated in the vacuoles of plant cells, except what is absorbed by the cell wall, allowing Cd to be released from plant tissues under moderate conditions. Cooking by the steaming process generally increased the bioaccessibility of Cd in French bean, carrot, and leek. For potato, few or no significant differences of Cd bioaccessibility were observed after the steaming process, while the frying process strongly decreased bioaccessibility in both phases. The estimation of metal bioaccessibility in vegetables is helpful for human health risk assessment.

  12. Greenhouse Gases

    MedlinePlus

    ... U.S. and international estimates of greenhouse gas emissions: Carbon dioxide (CO2) Methane (CH4) Nitrous oxide (N2O) Industrial ... From Outlook for Future Emissions FAQs How much carbon dioxide is produced when different fuels are burned? — ...

  13. Lead and cadmium contamination and exposure risk assessment via consumption of vegetables grown in agricultural soils of five-selected regions of Pakistan.

    PubMed

    Rehman, Zahir Ur; Khan, Sardar; Brusseau, Mark L; Shah, Mohammad Tahir

    2017-02-01

    Rapid urbanization and industrialization result in serious contamination of soil with toxic metals such as lead (Pb) and cadmium (Cd), which can lead to deleterious health impacts in the exposed population. This study aimed to investigate Pb and Cd contamination in agricultural soils and vegetables in five different agricultural sites in Pakistan. The metal transfer from soil-to-plant, average daily intake of metals, and health risk index (HRI) were also characterized. The Pb concentrations for all soils were below the maximum allowable limits (MAL 350 mg kg(-1)) set by State Environmental Protection Administration of China (SEPA), for soils in China, while Cd concentrations in the soils were exceeded the MAL (61.7-73.7% and 4.39-34.3%) set by SEPA (0.6 mg kg(-)), and European Union, (1.5 mg kg(-1)) respectively. The mean Pb concentration in edible parts of vegetables ranged from 1.8 to 11 mg kg(-1). The Pb concentrations for leafy vegetables were higher than the fruiting and pulpy vegetables. The Pb concentrations exceeded the MAL (0.3 mg kg(-1)) for leafy vegetables and the 0.1 mg kg(-1) MAL for fruity and rooty/tuber vegetables set by FAO/WHO-CODEX. Likewise, all vegetables except Pisum sativum (0.12 mg kg(-1)) contained Cd concentrations that exceeded the MAL set by SEPA. The HRI values for Pb and Cd were <1 for both adults and children for most of the vegetable species except Luffa acutangula, Solanum lycopersicum, Benincasa hispada, Momordi charantia, Aesculantus malvaceae, Cucumis sativus, Praecitrullus fistulosus, Brassica oleracea, and Colocasia esculanta for children. Based on these results, consumption of these Pb and Cd contaminated vegetables poses a potential health risk to the local consumers. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Gardener's solar greenhouse: how to build and use a solar greenhouse for year-round gardening

    SciTech Connect

    Wolf, R.

    1984-01-01

    The design of a solar greenhouse is presented. Subtleties of its use are discussed, and site selection criteria for it are discussed. Rather complete instructions for construction are presented in sections. Separate sections are included for foundation, framing, glazing and trim, and movable insulation. Recipes for using the goodies grown in the greenhouse are also included. 92 figures.

  15. Urban Options Solar Greenhouse Demonstration Project. Final report

    SciTech Connect

    Cipparone, L.

    1980-10-15

    The following are included: the design process, construction, thermal performance, horticulture, educational activities, and future plans. Included in appendices are: greenhouse blueprints, insulating curtain details, workshop schedules, sample data forms, summary of performance calculations on the Urban Options Solar Greenhouse, data on vegetable production, publications, news articles on th Solar Greenhouse Project, and the financial statement. (MHR)

  16. Effect of biweekly shoot tip harvests on the growth and yield of Georgia Jet sweet potato grown hydroponically

    NASA Technical Reports Server (NTRS)

    Ogbuehi, Cyriacus R.; Loretan, Phil A.; Bonsi, C. K.; Hill, Walter A.; Morris, Carlton E.; Biswas, P. K.; Mortley, Desmond G.

    1989-01-01

    Sweet potato shoot tips have been shown to be a nutritious green vegetable. A study was conducted to determine the effect of biweekly shoot tip harvests on the growth and yield of Georgia Jet sweet potato grown in the greenhouse using the nutrient film technique (NFT). The nutrient solution consisted of a modified half Hoagland solution. Biweekly shoot tip harvests, beginning 42 days after planting, provided substantial amounts of vegetable greens and did not affect the fresh and dry foliage weights or the storage root number and fresh and dry storage root weights at final harvest. The rates of anion and cation uptake were not affected by tip harvests.

  17. Heavy metal pollution in vegetables grown in the vicinity of a multi-metal mining area in Gejiu, China: total concentrations, speciation analysis, and health risk.

    PubMed

    Li, Yanyan; Wang, Hongbin; Wang, Haijuan; Yin, Fei; Yang, Xiaoyan; Hu, Yongjun

    2014-11-01

    A field survey was conducted to investigate the present situation and health risk of arsenic (As), lead (Pb), cadmium (Cd), copper (Cu), and zinc (Zn) in soils and vegetables in a multi-metal mining area, Gejiu, China. Furthermore, three vegetables (water spinach, potato, and summer squash) containing high metal concentrations were selected to further analyze metal speciation. The results showed that the average concentrations of five metals in soil exceeded the limiting values, and their bioavailable concentrations were significantly positively correlated to the total ones. Heavy metals in the edible parts of vegetables also exceeded the corresponding standards. The leaves of pakchoi, peppermint, and coriander had a strong metal-accumulative ability and they were not suitable for planting. Except the residue forms, the main forms of metals in the edible parts of three selected vegetables were ethanol-, NaCl-, and HAc-extractable fractions for As, Pb, and Cd, respectively; however, Cu was mainly presented as NaCl-extractable and Zn as HAc-extractable fractions. A high proportion of ethanol-extractable As showed that As bioactivity and toxic effects were the highest. Although the total and bioavailable Cd were high in soil, its speciation in vegetables was mainly presented as HAc-extractable fraction, which has a relatively low bioactivity. Lead and arsenic were imposing a serious threat on the local residents via vegetable consumption.

  18. Three years exclusion of large herbivores in a high arctic mire in NE Greenland resulted in changed vegetation density and greenhouse gas emission and uptake

    NASA Astrophysics Data System (ADS)

    Falk, Julie M.; Schmidt, Niels Martin; Christensen, Torben R.; Forchhammer, Mads C.; Jackowicz-Korczynski, Marcin; Ström, Lena

    2014-05-01

    Herbivory is an important part of many ecosystems and their presence effects the ecosystems carbon balance with both direct and indirect effects. Little is known about what will happen to an arctic ecosystem that is influenced by herbivory, if the animals disappear. We hypothesized that trampling and grazing by large herbivores influence the vegetation density and composition and hereby the carbon balance. Method: In 2010 an in-situ field experiment in Zackenberg, NE Greenland, were initiated to study the effects of herbivory on the vegetation and carbon balance. Exclosures were established to exclude the muskoxen (Ovibos moschatus), which are a natural part of these ecosystems. The experiment consists of five block replicates with three treatments within each block, i.e., control, exclosure and a snow fence (the treatment area is 10x10 m and the fences are 1 m high). During the growing season we have since 2011 performed weekly measurements of CO2 and CH4fluxes, the concentration of labile substrate for CH4 formation (organic acid concentration) in pore-water and additional ecosystem properties, i.e., water table depth, active layer depth and soil temperature. In 2013 a detailed analysis of the vascular plant species composition and density within each measurement plot were performed. Furthermore biomass (including mosses) samples 20x20 cm were harvested within all treatments. Results: The third year after the initiation of the experiment we observed a clear effect of excluding muskoxen grazing from the ecosystem. The exclosures had lower uptake of CO2 and lower CH4 emission. The vegetation analysis inside the plots showed a decrease in total number of vascular tillers and of Eriophorum scheuchzeri (ES) tillers. Correspondingly, the biomass samples from the exclosures had lower number of total plant tillers, ES tillers, total green leaves and green ES leaves and the height of all vascular plants and of ES plants were higher. Finally, the dry weight of the biomass

  19. Influence of CO2 change during 90-day experiment on growth characteristics and photosynthetic activity in vegetables grown in Lunar Palace 1

    NASA Astrophysics Data System (ADS)

    Shao, Lingzhi; Liu, Hong; Wang, Minjuan; Fu, Yuming; Dong, Chen; Liu, Guanghui

    To establish bioregenerative life support system (BLSS) on lunar or Mars bases in the future, it is necessary to firstly conduct manned simulation experiments on the ground. For this purpose, Lunar palace 1 as an integrative experimental facility for permanent astrobase life support artificial closed ecosystem was set up, and 90-day experiment was carried out in this system. Vegtables as one of the important plant units, provide various nutrient content for crews in the system, such as vitamin, antioxidants and so on. However, it is not clear yet that how the CO _{2} change during 90-day experiment to affect on growth characteristics and photosynthetic activity in vegtables grown in the system. In this study, red lettuce, red rape, romaine lettuce, and bibb lettuce grown in the system were chosen as the subject investigated. Growth, expressed as dry weight, length of shoot and root, leaf area, was mearsured, and photosynthesis,expressed as net photosynthetic rate, intercellular CO _{2} concentration, chlorophyll contents and fluorescence was analyzed to detemind influence of CO _{2} change during 90-day experiment on growth in vegtables grown in the system.

  20. [Growth and development of plants in a row of generations under the conditions of space flight (experiment Greenhouse-5)

    NASA Technical Reports Server (NTRS)

    Levinskikh, M. A.; Sychev, V. N.; Derendiaeva, T. A.; Signalova, O. B.; Podol'skii, I. G.; Avdeev, S. V.; Bingheim, G. E.; Campbell, W. F. (Principal Investigator)

    2001-01-01

    Results of the experiment aimed at harvesting a second space generation of wheat var. Apogee in Mir greenhouse Svet (experiment GREENHOUSE-5) are presented. In space flight, germination rate of space seeds from the first crop made up 89% against 100% of the ground seeds. The full biological ripeness was observed in 20 plants grown from the ground seeds and one plant grown from the space seeds following 80- to 90-d vegetation. The plant of the second space generation was morphologically different neither from the species in the first space crop nor from the ground controls. To study the biological characteristics of Apogee seeds gathered in the first and second crops in spaceflight experiment GREENHOUSE-5, the seeds were planted on their return to the laboratory. Morphometric analysis showed that they were essentially similar to the controls. Hence, the space experiments in Mir greenhouse Svet performed during 1998-1999 gave proof that plants cultivated in microgravity can pass the ontogenetic cycle more than once. However, initial results of the investigations into growth and development of plants through several generations are still in-sufficient to speak of possible delayed effects of the spaceflight factors (microgravity, multicomponent radiation, harmful trace contaminants etc.).

  1. [Growth and development of plants in a row of generations under the conditions of space flight (experiment Greenhouse-5)

    NASA Technical Reports Server (NTRS)

    Levinskikh, M. A.; Sychev, V. N.; Derendiaeva, T. A.; Signalova, O. B.; Podol'skii, I. G.; Avdeev, S. V.; Bingheim, G. E.; Campbell, W. F. (Principal Investigator)

    2001-01-01

    Results of the experiment aimed at harvesting a second space generation of wheat var. Apogee in Mir greenhouse Svet (experiment GREENHOUSE-5) are presented. In space flight, germination rate of space seeds from the first crop made up 89% against 100% of the ground seeds. The full biological ripeness was observed in 20 plants grown from the ground seeds and one plant grown from the space seeds following 80- to 90-d vegetation. The plant of the second space generation was morphologically different neither from the species in the first space crop nor from the ground controls. To study the biological characteristics of Apogee seeds gathered in the first and second crops in spaceflight experiment GREENHOUSE-5, the seeds were planted on their return to the laboratory. Morphometric analysis showed that they were essentially similar to the controls. Hence, the space experiments in Mir greenhouse Svet performed during 1998-1999 gave proof that plants cultivated in microgravity can pass the ontogenetic cycle more than once. However, initial results of the investigations into growth and development of plants through several generations are still in-sufficient to speak of possible delayed effects of the spaceflight factors (microgravity, multicomponent radiation, harmful trace contaminants etc.).

  2. Assessment of the potential health risks associated with the aluminium, arsenic, cadmium and lead content in selected fruits and vegetables grown in Jamaica.

    PubMed

    Antoine, Johann M R; Fung, Leslie A Hoo; Grant, Charles N

    2017-01-01

    Thirteen Jamaican-grown food crops - ackee (Blighia sapida), banana (Musa acuminate), cabbage (Brassica oleracea), carrot (Daucus carota), cassava (Manihot esculenta), coco (Xanthosoma sagittifolium), dasheen (Colocasia esculenta), Irish potato (Solanum tuberosum), pumpkin (Cucurbita pepo), sweet pepper (Capsicum annuum), sweet potato (Ipomoea batatas), tomato (Solanum lycopersicum) and turnip (Brassica rapa) - were analysed for aluminium, arsenic, cadmium and lead by atomic absorption spectrophotometry and instrumental neutron activation analysis. The fresh weight mean concentrations in these food crops (4.25-93.12 mg/kg for aluminium; 0.001-0.104 mg/kg for arsenic; 0.015-0.420 mg/kg for cadmium; 0.003-0.100 mg/kg for lead) were used to calculate the estimated daily intake (EDI), target hazard quotient (THQ), hazard index (HI) and target cancer risk (TCR) for arsenic, associated with dietary exposure to these potentially toxic elements. Each food type had a THQ and HI < 1 indicating no undue non-carcinogenic risk from exposure to a single or multiple potentially toxic elements from the same food. The TCR for arsenic in these foods were all below 1 × 10(-4), the upper limit used for acceptable cancer risk. There is no significant health risk to the consumer associated with the consumption of these Jamaican-grown food crops.

  3. Super-optimal CO2 reduces wheat yield in growth chamber and greenhouse environments

    NASA Astrophysics Data System (ADS)

    Grotenhuis, T.; Reuveni, J.; Bugbee, B.

    1997-01-01

    Seven growth chamber trials (six replicate trials using 0.035, 0.12, and 0.25 % CO_2 in air and one trial using 0.12, 0.80, and 2.0% CO_2 in air) and three replicate greenhouse trials (0.035, 0.10, 0.18, 0.26, 0.50, and 1.0% CO_2 in air) compare the effects of super-optimal CO_2 on the seed yield, harvest index, and vegetative growth rate of wheat (Triticum aestivum L. cvs. USU-Apogee and Veery-10). Plants in the growth chamber trials were grown hydroponically under fluorescent lamps, while the greenhouse trials were grown under sunlight and high pressure sodium lamps and in soilless media. Plants in the greenhouse trials responded similarly to those in the growth chamber trials; maximum yields occurred near 0.10 and 0.12 % CO_2 and decreased significantly thereafter. This research indicates that the toxic effects of elevated CO_2 are not specific to only one environment and has important implications for the design of bio-regenerative life support systems in space, and for the future of terrestrial agriculture.

  4. [Growth and development of plants in a sequence of generations under the conditions of space flight (experiment Greenhouse-3)

    NASA Technical Reports Server (NTRS)

    Levinskikh, M. A.; Sychev, V. N.; Signalova, O. B.; Derendiaeva, T. A.; Podol'skii, I. G.; Masgreiv, M. E.; Bingheim, G. E.; Musgrave, M. E. (Principal Investigator); Campbell, W. F. (Principal Investigator)

    2001-01-01

    The purpose was to study characteristic features of growth and development of several plant generations in space flight in experiment GREENHOUSE-3 as a part of the Russian-US space research program MIR/NASA in 1997. The experiment consisted of cultivation of Brassica rapa L. in board greenhouse Svet. Two vegetative cycles were fully completed and the third vegetation was terminated on day 13 on the phase of budding. The total duration of the space experiment was 122 days, i.e. same as in the ground controls. In the experiment with Brassica rapa L. viable seeds produced by the first crop were planted in space flight and yielded next crop. Crops raised from the ground and space seeds were found to differ in height and number of buds. Both parameters were lowered in the plants grown from the space seeds. The prime course for smaller size and reduced organogenic potential of plantTs reproductive system seems to be a less content of nutrients in seeds that had matured in the space flight. Experiment GREENHOUSE-3 demonstrated principle feasibility of plant reproduction in space greenhouse from seeds developed in microgravity.

  5. [Growth and development of plants in a sequence of generations under the conditions of space flight (experiment Greenhouse-3)

    NASA Technical Reports Server (NTRS)

    Levinskikh, M. A.; Sychev, V. N.; Signalova, O. B.; Derendiaeva, T. A.; Podol'skii, I. G.; Masgreiv, M. E.; Bingheim, G. E.; Musgrave, M. E. (Principal Investigator); Campbell, W. F. (Principal Investigator)

    2001-01-01

    The purpose was to study characteristic features of growth and development of several plant generations in space flight in experiment GREENHOUSE-3 as a part of the Russian-US space research program MIR/NASA in 1997. The experiment consisted of cultivation of Brassica rapa L. in board greenhouse Svet. Two vegetative cycles were fully completed and the third vegetation was terminated on day 13 on the phase of budding. The total duration of the space experiment was 122 days, i.e. same as in the ground controls. In the experiment with Brassica rapa L. viable seeds produced by the first crop were planted in space flight and yielded next crop. Crops raised from the ground and space seeds were found to differ in height and number of buds. Both parameters were lowered in the plants grown from the space seeds. The prime course for smaller size and reduced organogenic potential of plantTs reproductive system seems to be a less content of nutrients in seeds that had matured in the space flight. Experiment GREENHOUSE-3 demonstrated principle feasibility of plant reproduction in space greenhouse from seeds developed in microgravity.

  6. Heavy metal accumulation in soils, plants, and hair samples: an assessment of heavy metal exposure risks from the consumption of vegetables grown on soils previously irrigated with wastewater.

    PubMed

    Massaquoi, Lamin Daddy; Ma, Hui; Liu, Xue Hui; Han, Peng Yu; Zuo, Shu-Mei; Hua, Zhong-Xian; Liu, Dian-Wu

    2015-12-01

    It is common knowledge that soils irrigated with wastewater accumulate heavy metals more than those irrigated with cleaner water sources. However, little is known on metal concentrations in soils and cultivars after the cessation of wastewater use. This study assessed the accumulation and health risk of heavy metals 3 years post-wastewater irrigation in soils, vegetables, and farmers' hair. Soils, vegetables, and hair samples were collected from villages previously irrigating with wastewater (experimental villages) and villages with no history of wastewater irrigation (control villages). Soil samples were digested in a mixture of HCL/HNO3/HCLO4/HF. Plants and hair samples were digested in HNO3/HCLO4 mixture. Inductive coupled plasma-optical emission spectrometer (ICP-OES) was used to determine metal concentrations of digested extracts. Study results indicate a persistence of heavy metal concentration in soils and plants from farms previously irrigated with wastewater. In addition, soils previously irrigated with wastewater were severely contaminated with cadmium. Hair metal concentrations of farmers previously irrigating with wastewater were significantly higher (P < 0.05) than farmers irrigating with clean water, but metal concentrations in hair samples of farmers previously irrigating with wastewater were not associated with current soil metal concentrations. The study concludes that there is a persistence of heavy metals in soils and plants previously irrigated with wastewater, but high metal concentrations in hair samples of farmers cannot be associated with current soil metal concentrations.

  7. Effect of drying and cooking on nutritional value and antioxidant capacity of morogo (Amaranthus hybridus) a traditional leafy vegetable grown in South Africa.

    PubMed

    Medoua, Gabriel Nama; Oldewage-Theron, Wilna H

    2014-04-01

    Morogo (vegetables in Tswana) is a green leafy vegetable from the Amaranthaceae family that can be harvested from wild growing or cultivated. The objective of this study was to determine the nutritional value, the total antioxidant capacity and selected bioactive compounds present in morogo leaves, and evaluate the effect of drying and cooking. Results showed that morogo contained a significant amount of protein (3.6 ± 0.1 g/100 g FW) and minerals which the level exceed 1% of fresh weight. The total antioxidant capacity (μmole TE/ 100 g FW) determined by DPPH and FRAP assays were 118.3 ± 15.3 and 128.4 ± 11.9 respectively. Total polyphenols (109.4 ± 7.5 mg GAE/100 g FW), vitamin C (36.6 ± 1.0 mg /100 g FW) and carotenoids represented by β carotene (25.3 ± 1.3 mg /100 g FW) and xanthophylls (7.48 ± 0.31 mg /100 g FW) formed a significant part of bioactive compounds content of morogo leaves. Since the boiling can cause significant losses of compounds in the boiling water, it can be recommended to avoid cooking methods that can include a boiling step with discard of boiling water.

  8. Program to monitor and evaluate a passive solar greenhouse/aquaculture system. Final report

    SciTech Connect

    Not Available

    1982-01-01

    A temperature monitoring program of Amity's solar greenhouse demonstrated that air, soil, and water temperatures can be maintained at optimal levels without supplemental heat. A foil reflector placed in front of the greenhouse glazing at an angle of between 0 and 5/sup 0/ above horizontal enhanced direct light entering the greenhouse by as much as 22%. Aquaculture in the water heat storage of a solar greenhouse has been a success. Fish reached harvest size in about seven months. The two species that were received the best by the public were African perch (Tilapia mossambica) and channel catfish (Ictalurus punctatus). Although carp (Cyprinus carpio) were the fastest growers they were not well received by the public. Linking hydroponics to greenhouse aquaculture shows a lot of promise. Different support medias were examined and tomatoes and European cucumbers were raised successfully. A savonius windmill was successfully linked to an aquaculture aeration system but because of the wind pattern in the Willamette valley the windmill system did not provide air in the evening when it was needed most. Alternate designs are discussed. Locally grown fish diets were evaluated for their ability to promote fish growth. Diets such as water hyacinth, duckweed, earthworms, beans, and comfrey were raised on the Amity site, pelleted with a hand grinder and solar dried. Duckweed and earthworms appear to hold promise for a nutritous, easy to grow and pelletize, food source. Amity's solar greenhouse, three coldframe designs and a PVC tunnel cloche were compared in a vegetable growing trial. Most impressive was the cloche design because it provided adequate protection, was inexpensive and very easy to build.

  9. Dissipation, half-lives, and mass spectrometric identification of endosulfan isomers and the sulfate metabolite on three field-grown vegetables.

    PubMed

    Antonious, George; Hill, Regina; Ross, Kyla; Coolong, Timothy

    2012-01-01

    Endosulfan 3 EC, a mixture of α- and β-stereo isomers, was sprayed on field-grown pepper, melon, and sweet potato plants at the recommended rate of 0.44 kg A.I. acre(-1). Plant tissue samples (leaves, fruits, or edible roots) were collected 1 h to 30 days following spraying and analyzed for endosulfan isomers (α- and β-isomers). Analysis of samples was accomplished using a gas chromatograph (GC) equipped with a mass detector in total ion mode. The results indicated the formation of endosulfan sulfate as the major metabolite of endosulfan sulfite and the relatively higher persistence of the β-isomers as compared to the α-isomer. The initial total residues (α- and β-isomers plus endosulfan sulfate) were higher on leaves than on fruits. On pepper and melon fruits, the α-isomer, which is the more toxic to mammals, dissipated faster (T(1/2) = 1.22 and 0.95 d, respectively) than the less toxic β-isomer (T(1/2) = 3.0 and 2.5 d, respectively). These results confirm the greater loss of the α-isomer compared to the β-isomer, which can ultimately impact endosulfan dissipation in the environment. Additionally, the higher initial residues of endosulfan on pepper and sweet potato leaves should be considered of great importance for timing field operations and the safe entry of harvesters due to the high mammalian toxicity of endosulfan.

  10. Gardening with Greenhouses

    ERIC Educational Resources Information Center

    Keeler, Rusty

    2010-01-01

    Greenhouses come in all shapes, sizes, and price ranges: from simple hand-built plastic-covered frames to dazzling geodesic domes. Some child care centers install greenhouses as a part of their outdoor garden space. Other centers have incorporated a greenhouse into the building itself. Greenhouses provide a great opportunity for children to grow…

  11. Gardening with Greenhouses

    ERIC Educational Resources Information Center

    Keeler, Rusty

    2010-01-01

    Greenhouses come in all shapes, sizes, and price ranges: from simple hand-built plastic-covered frames to dazzling geodesic domes. Some child care centers install greenhouses as a part of their outdoor garden space. Other centers have incorporated a greenhouse into the building itself. Greenhouses provide a great opportunity for children to grow…

  12. The Greenhouse: A Place for Year-Round Plant Investigations.

    ERIC Educational Resources Information Center

    Hanif, Muhammad

    1989-01-01

    Activities that may take place in a greenhouse are discussed. Included are learning how to grow plants, plant growth, soil, vegetative reproduction, and plant habitat adaptations. Materials, procedures, and results are presented for the activities. (CW)

  13. Induced abnormality in Mir- and earth grown super dwarf wheat

    NASA Astrophysics Data System (ADS)

    Bubenheim, D. L.; Stieber, J.; Campbell, W. F.; Salisbury, F. B.; Levinski, M.; Sytchev, V.; Pdolsky, I.; Chernova, L.

    Super-dwarf wheat grown on the Mir space station using the Svet ``Greenhouse'' exhibited morphological, metabolic and reproductive abnormalities compared with Earth-grown wheat. Of prominent importance were the abnormalities associated with reproductive ontogeny and the total absence of seed formation on Mir. Changes in the apical meristem associated with transition from the vegetative phase to floral initiation and development of the reproductive spike were all typical of `Super-Dwarf' wheat up to the point of anthesis. Observation of ruptured anthers from the Mir-grown plants revealed what appeared to be normally developed pollen. These pollen gains, however, contained only one nuclei, while normal viable pollen is tri-nucleate. A potentially important difference in the flight experiment, compared with ground reference studies, was the presence of a high level of atmospheric ethylene (1,200 ppb). Ground studies conducted by exposing `Super-Dwarf' wheat to ethylene just prior to anthesis resulted in manifestation of the same abnormalities observed in the space flight samples.

  14. Induced abnormality in Mir- and Earth grown Super Dwarf wheat

    NASA Technical Reports Server (NTRS)

    Bubenheim, D. L.; Stieber, J.; Campbell, W. F.; Salisbury, F. B.; Levinski, M.; Sytchev, V.; Podolsky, I.; Chernova, L.; Pdolsky, I.

    2003-01-01

    Super-dwarf wheat grown on the Mir space station using the Svet "Greenhouse" exhibited morphological, metabolic and reproductive abnormalities compared with Earth-grown wheat. Of prominent importance were the abnormalities associated with reproductive ontogeny and the total absence of seed formation on Mir. Changes in the apical meristem associated with transition from the vegetative phase to floral initiation and development of the reproductive spike were all typical of 'Super-Dwarf' wheat up to the point of anthesis. Observation of ruptured anthers from the Mir-grown plants revealed what appeared to be normally developed pollen. These pollen gains, however, contained only one nuclei, while normal viable pollen is tri-nucleate. A potentially important difference in the flight experiment, compared with ground reference studies, was the presence of a high level of atmospheric ethylene (1,200 ppb). Ground studies conducted by exposing 'Super-Dwarf' wheat to ethylene just prior to anthesis resulted in manifestation of the same abnormalities observed in the space flight samples. c2002 Published by Elsevier Science Ltd on behalf of COSPAR.

  15. Induced abnormality in Mir- and Earth grown Super Dwarf wheat

    NASA Technical Reports Server (NTRS)

    Bubenheim, D. L.; Stieber, J.; Campbell, W. F.; Salisbury, F. B.; Levinski, M.; Sytchev, V.; Podolsky, I.; Chernova, L.; Pdolsky, I.

    2003-01-01

    Super-dwarf wheat grown on the Mir space station using the Svet "Greenhouse" exhibited morphological, metabolic and reproductive abnormalities compared with Earth-grown wheat. Of prominent importance were the abnormalities associated with reproductive ontogeny and the total absence of seed formation on Mir. Changes in the apical meristem associated with transition from the vegetative phase to floral initiation and development of the reproductive spike were all typical of 'Super-Dwarf' wheat up to the point of anthesis. Observation of ruptured anthers from the Mir-grown plants revealed what appeared to be normally developed pollen. These pollen gains, however, contained only one nuclei, while normal viable pollen is tri-nucleate. A potentially important difference in the flight experiment, compared with ground reference studies, was the presence of a high level of atmospheric ethylene (1,200 ppb). Ground studies conducted by exposing 'Super-Dwarf' wheat to ethylene just prior to anthesis resulted in manifestation of the same abnormalities observed in the space flight samples. c2002 Published by Elsevier Science Ltd on behalf of COSPAR.

  16. Induced Abnormality In Mir- and Earth-Grown Super Dwarf Wheat

    NASA Technical Reports Server (NTRS)

    Bubenheim, David L.; Stieber, Joseph; Campbell, William F.; Salisbury, Frank B.; Levinski, Margarita; Sytchev, Vladimir; Podolsky, Igor; Chernova, Lola; Ivanova, Irene; Kliss, Mark (Technical Monitor)

    1998-01-01

    Super-dwarf wheat grown on the Mir space station using the Svet "Greenhouse" exhibited morphological, metabolic and reproductive abnormalities compared with normal wheat. Of prominent importance were the abnormalities associated with reproductive ontogeny and the total absence of seed formation on Mir. Changes in the apical meristem associated with transition from the vegetative phase to floral initiation and development of the reproductive spike were all typical of 'Super Dwarf' wheat up to the point of anthesis. Observation of ruptured anthers from the Mir-grown plants revealed what appeared to be normally developed pollen. These pollen grains however, contain only one nucleus, while normal viable pollen is trinucleate. A potentially important difference in the flight experiment, compared with ground reference studies, was identified - a high level of atmospheric ethylene (1200 ppb). Ground studies conducted exposing "Super-dwarf" wheat to ethylene at just prior to anthesis resulted in manifestation of the same abnormalities observed in the space flight samples.

  17. Induced Abnormality In Mir- and Earth-Grown Super Dwarf Wheat

    NASA Technical Reports Server (NTRS)

    Bubenheim, David L.; Stieber, Joseph; Campbell, William F.; Salisbury, Frank B.; Levinski, Margarita; Sytchev, Vladimir; Podolsky, Igor; Chernova, Lola; Ivanova, Irene; Kliss, Mark (Technical Monitor)

    1998-01-01

    Super-dwarf wheat grown on the Mir space station using the Svet "Greenhouse" exhibited morphological, metabolic and reproductive abnormalities compared with normal wheat. Of prominent importance were the abnormalities associated with reproductive ontogeny and the total absence of seed formation on Mir. Changes in the apical meristem associated with transition from the vegetative phase to floral initiation and development of the reproductive spike were all typical of 'Super Dwarf' wheat up to the point of anthesis. Observation of ruptured anthers from the Mir-grown plants revealed what appeared to be normally developed pollen. These pollen grains however, contain only one nucleus, while normal viable pollen is trinucleate. A potentially important difference in the flight experiment, compared with ground reference studies, was identified - a high level of atmospheric ethylene (1200 ppb). Ground studies conducted exposing "Super-dwarf" wheat to ethylene at just prior to anthesis resulted in manifestation of the same abnormalities observed in the space flight samples.

  18. A Greenhouse for Mars and Beyond

    NASA Astrophysics Data System (ADS)

    Rahaim, Christopher P.; Czysz, Paul A.

    2008-01-01

    A detailed design study for a deployable greenhouse for Mars mission is has been completed. The greenhouse has been designed so that it has a life span of at least 20 years, a leakage rate of no more that 1% of the total volume per day at the target working pressure of 50 kPa and provides at least six crewmembers with approximately twenty five percent of their food supply. Artificial light is provided by high intensity red and blue light emitting diodes, but sunlight is also used by installing small Lexan windows on the rooftop. The greenhouse structure is a rigid IM7/977-3 graphite/epoxy sandwich structure with a footprint of 38 m2. Radioisotope thermal electric generators are used to produce power for the greenhouse and its subsystems and the plants are grown in nested pockets located on vertical cylinders which allows for a growth area of 48 m2. An aeroponic water and nutrient delivery system is used in order to reduce the greenhouse water usage. Harvesting and planting is achieved through the use of robotics specifically designed for this mission. The greenhouse structure and subsystems have a total weight of less than 10 metric tons. In this paper the design highlights of several of the subsystems of the greenhouse design will be summarized.

  19. Response of sun-grown and shade-grown northern red oak seedlings to outplanting in clearcuts and shelterwoods in North Alabama

    Treesearch

    Callie Jo Schweitzer; Emile S. Gardiner; David L. Loftis

    2006-01-01

    The primary objective of this study was to determine if greenhouse light environment would affect outplanting success for northern red oak (Quercus rubra L.) in clearcuts and shelterwoods. In 2002, northern red oak seedlings were grown from acorns under full-ambient (sun) and half-ambient (shade) light conditions in a greenhouse. Seedlings grown...

  20. Growing Media Affect Size of Container-Grown Red Pine

    Treesearch

    Howard M. Phipps

    1974-01-01

    Red pine seedlings were grown in nine different soil media and in two types of containers in a greenhouse. Growth differed significantly among the media after 16 weeks, with the largest seedlings produced in a peat-vermiculite mix

  1. Pesticide residue analysis of vegetables by gas chromatography with electron-capture detection.

    PubMed

    Fenoll, José; Hellín, Pilar; Martínez, Carmen M; Flores, Pilar

    2007-01-01

    A new and original analytical method was developed for the routine analysis of 28 multiclass pesticide residues in vegetables (green pepper, red pepper, and tomato). The extraction was performed with acetone, and the pesticides were partitioned into ethyl acetate-cyclohexane (1 + 1, v/v). Residue levels in vegetables were determined by gas chromatography (GC) with electron-capture detection. Residue identities were confirmed by GC coupled with mass spectrometry in the selected ion monitoring mode. The average recoveries in pepper and tomato obtained for all analytes studied were 67.3 and 123.1%, respectively, with relative standard deviation between 1.8 and 7.0%. The detection limit for the pesticides studied varied from 0.1 to 2.6 microg/kg. The proposed method was applied to the analysis of these compounds in vegetables grown in experimental greenhouses.

  2. The Dynamic Greenhouse Challenge

    ERIC Educational Resources Information Center

    Roman, Harry T.

    2010-01-01

    Greenhouses are marvelous devices, allowing one to enjoy the flower spectacle of summer all year round. At night, greenhouses use supplemental heat to keep the fragile plants warm. Over the last 30 years, greenhouse technology has undergone many changes, with the structures being automated and monitored and low-cost plastic structures emerging as…

  3. The Dynamic Greenhouse Challenge

    ERIC Educational Resources Information Center

    Roman, Harry T.

    2010-01-01

    Greenhouses are marvelous devices, allowing one to enjoy the flower spectacle of summer all year round. At night, greenhouses use supplemental heat to keep the fragile plants warm. Over the last 30 years, greenhouse technology has undergone many changes, with the structures being automated and monitored and low-cost plastic structures emerging as…

  4. Carbon balance, partitioning and photosynthetic acclimation in fruit-bearing grapevine (Vitis vinifera L. cv. Tempranillo) grown under simulated climate change (elevated CO2, elevated temperature and moderate drought) scenarios in temperature gradient greenhouses.

    PubMed

    Salazar-Parra, Carolina; Aranjuelo, Iker; Pascual, Inmaculada; Erice, Gorka; Sanz-Sáez, Álvaro; Aguirreolea, Jone; Sánchez-Díaz, Manuel; Irigoyen, Juan José; Araus, José Luis; Morales, Fermín

    2015-02-01

    Although plant performance under elevated CO2 has been extensively studied in the past little is known about photosynthetic performance changing simultaneously CO2, water availability and temperature conditions. Moreover, despite of its relevancy in crop responsiveness to elevated CO2 conditions, plant level C balance is a topic that, comparatively, has received little attention. In order to test responsiveness of grapevine photosynthetic apparatus to predicted climate change conditions, grapevine (Vitis vinifera L. cv. Tempranillo) fruit-bearing cuttings were exposed to different CO2 (elevated, 700ppm vs. ambient, ca. 400ppm), temperature (ambient vs. elevated, ambient +4°C) and irrigation levels (partial vs. full irrigation). Carbon balance was followed monitoring net photosynthesis (AN, C gain), respiration (RD) and photorespiration (RL) (C losses). Modification of environment (13)C isotopic composition (δ(13)C) under elevated CO2 (from -10.30 to -24.93‰) enabled the further characterization of C partitioning into roots, cuttings, shoots, petioles, leaves, rachides and berries. Irrespective of irrigation level and temperature, exposure to elevated CO2 induced photosynthetic acclimation of plants. C/N imbalance reflected the inability of plants grown at 700ppm CO2 to develop strong C sinks. Partitioning of labeled C to storage organs (main stem and roots) did not avoid accumulation of labeled photoassimilates in leaves, affecting negatively Rubisco carboxylation activity. The study also revealed that, after 20 days of treatment, no oxidative damage to chlorophylls or carotenoids was observed, suggesting a protective role of CO2 either at current or elevated temperatures against the adverse effect of water stress. Copyright © 2014 Elsevier GmbH. All rights reserved.

  5. Accumulation and health risk of heavy metals in vegetables from harmless and organic vegetable production systems of China.

    PubMed

    Chen, Yong; Hu, Wenyou; Huang, Biao; Weindorf, David C; Rajan, Nithya; Liu, Xiaoxiao; Niedermann, Silvana

    2013-12-01

    Heavy metal accumulation in vegetables is a growing concern for public health. Limited studies have elucidated the heavy metal accumulation characteristics and health risk of different vegetables produced in different facilities such as greenhouses and open-air fields and under different management modes such as harmless and organic. Given the concern over the aforementioned factors related to heavy metal accumulation, this study selected four typical greenhouse vegetable production bases, short-term harmless greenhouse vegetable base (SHGVB), middle-term harmless greenhouse vegetable base (MHGVB), long-term harmless greenhouse vegetable base (LHGVB), and organic greenhouse vegetable base (OGVB), in Nanjing City, China to study heavy metal accumulation in different vegetables and their associated health risks. Results showed that soils and vegetables from SHGVB and OGVB apparently accumulated fewer certain heavy metals than those from other bases, probably due to fewer planting years and special management, respectively. Greenhouse conditions significantly increased certain soil heavy metal concentrations relative to open-air conditions. However, greenhouse conditions did not significantly increase concentrations of As, Cd, Cu, Hg, and Zn in leaf vegetables. In fact, under greenhouse conditions, Pb accumulation was effectively reduced. The main source of soil heavy metals was the application of large amounts of low-grade fertilizer. There was larger health risk for producers' children to consume vegetables from the three harmless vegetable bases than those of residents' children. The hazard index (HI) over a large area exceeded 1 for these two kinds of children in the MHGVB and LHGVB. There was also a slight risk in the SHGVB for producers' children solely. However, the HI of the whole area of the OGVB for two kinds of children was below 1, suggesting low risk of heavy metal exposure through the food chain. Notably, the contribution rate of Cu and Zn to the HI were

  6. 4. Perspective view, greenhouse, from the southwest. The greenhouse is ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. Perspective view, greenhouse, from the southwest. The greenhouse is the portion of the seed house to the right (south) of the double doors. - John Bartram House & Garden, Greenhouse, 54th Street & LIndbergh Boulevard, Philadelphia, Philadelphia County, PA

  7. Thoughts from the Greenhouse

    ERIC Educational Resources Information Center

    Sonstrom, Wendy Jean

    2006-01-01

    In this article, the author compares the functions of a graduate adult education program and a greenhouse. A graduate adult education program is a place where, like in a greenhouse, exciting new hybrids can be developed--working with people outside the school of education, in different disciplines and beyond the university's walls, sharing what…

  8. Thoughts from the Greenhouse

    ERIC Educational Resources Information Center

    Sonstrom, Wendy Jean

    2006-01-01

    In this article, the author compares the functions of a graduate adult education program and a greenhouse. A graduate adult education program is a place where, like in a greenhouse, exciting new hybrids can be developed--working with people outside the school of education, in different disciplines and beyond the university's walls, sharing what…

  9. Increasing the Vegetable Intake Dose Is Associated with a Rise in Plasma Carotenoids without Modifying Oxidative Stress or Inflammation in Overweight or Obese Postmenopausal Women123

    PubMed Central

    Crane, Tracy E.; Kubota, Chieri; West, Julie L.; Kroggel, Mark A.; Wertheim, Betsy C.; Thomson, Cynthia A.

    2011-01-01

    The optimal amount of vegetable consumption required to reduce chronic disease risk is widely debated. Intervention trials evaluating biological activity of vegetables at various doses are limited. We conducted a 3-dose, crossover feeding trial to test the hypothesis that vegetable intake is associated in a dose-dependent manner with increased plasma carotenoids and subsequently reduced oxidative stress and inflammation in 49 overweight, postmenopausal women. Participants were assigned in random order to 2 (130 g), 5 (287 g), and 10 (614 g) daily servings of fresh, greenhouse-grown vegetables for 3-wk intervals with a 4-wk washout period between treatments. Plasma total carotenoids significantly increased from 1.63 to 2.07 μmol/L with a dose of 2 vegetable servings, from 1.49 to 2.84 μmol/L with a dose of 5 vegetable servings, and from 1.40 to 4.42 μmol/L with a dose of 10 vegetable servings (pre-post paired ttests, all P < 0.001). The change during each feeding period increased with each dose level (P < 0.001). Urine concentrations of 8-isoprostane F2α, hexanoyl lysine, and serum high sensitivity C-reactive protein were not affected by any administered vegetable dose. In this variable-dose vegetable study, a dose-response for plasma carotenoids was demonstrated without significant change in oxidative stress and inflammation in overweight, postmenopausal women. PMID:21865569

  10. Cannabis plants illicitly grown in Jutland (Denmark).

    PubMed

    Kaa, E

    1989-01-01

    Four hundred forty-nine fresh cannabis plants and 26 fruiting tops harvested in Jutland (Denmark) from July to September 1988 were characterized according to weight, height, marihuana yield, and cannabinoid content. The median weights were 308 g and 584 g for plants grown outdoors (n = 418) and in greenhouses (n = 31), respectively. The average marihuana yield was 8.7% for the plants grown outdoors and slightly lower for the greenhouse plants. Great variations, however, were seen both between and within the individual harvests. The mean concentration of total THC (tetrahydrocannabinol) was 0.87% for the plants grown outdoors. An increase according to the month of harvest was observed. For plants grown in greenhouses the mean value of total THC was 1.35%, while the mean concentration of fruiting tops was 2.13%. All plants contained cannabidiol (CBD), but only negligible concentrations of other cannabinoids. In approximately 80% of the plants the THC content was higher than the CBD content (drug type), while the rest either contained equal concentrations (intermediate type) or most CBD (fiber type).

  11. Metabolic profiling of turmeric (Curcuma longa L.) plants derived from in vitro micropropagation and conventional greenhouse cultivation.

    PubMed

    Ma, Xiaoqiang; Gang, David R

    2006-12-13

    Turmeric (Curcuma longa) was considered only a culinary spice in many parts of the world until the notable anti-inflammation curcuminoids were discovered from this herb. Because it is a sterile triploid and is propagated vegetatively by rhizome division, turmeric is susceptible to pathogens that accumulate and are transmitted from generation to generation, and amplification of particularly useful stocks is a slow process. An in vitro propagation method has been developed to alleviate these problems. Metabolic profiling, using GC-MS and LC-ESI-MS, was used to determine if chemical differences existed between greenhouse-grown and in vitro micropropagation derived plants. The major chemical constituent curcuminoids, a group of diarylheptanoid compounds, as well as major mono- and sesquiterpenoids were identified and quantified. Principal component analysis and hierarchical cluster analysis revealed chemical differences between lines (T3C turmeric vs Hawaiian red turmeric) and tissues (rhizome, root, leaf, and shoot). However, this analysis indicated that no significant differences existed between growth treatments (conventional greenhouse-grown vs in vitro propagation derived plants).

  12. Sustainability of Switchgrass for Cellulosic Ethanol: Evaluating Net Energy, Greenhouse Gas Emissions, and Feedstocks Costs

    USDA-ARS?s Scientific Manuscript database

    Perennial herbaceous plants such as switchgrass are being evaluated as cellulosic bioenergy crops. Sustainability concerns with switchgrass (Panicum virgatum L.) and similar energy crops have been about net energy efficiency, potential greenhouse gas (GHG) emissions, and economic feasibility grown ...

  13. Productivity of Mizuna Cultivated in the Space Greenhouse Onboard the Russian Module of the Iss

    NASA Astrophysics Data System (ADS)

    Levinskikh, Margarita; Sychev, Vladimir; Podolsky, Igor; Bingham, Gail; Moukhamedieva, Lana

    As stipulated by the science program of research into the processes of growth, development, metabolism and reproduction of higher plants in microgravity in view of their potential use in advanced life support systems, five experiments on Mizuna plants (Brassica rapa var. nipponisica) were performed using the Lada space greenhouse onboard the ISS Russian Module (RM) during Expeditions ISS-5, 17 and 20-22. One of the goals of the experiments was to evaluate the productivity of Mizuna plants grown at different levels of ISS RM air contamination. Mizuna plants were cultivated for 31 - 36 days when exposed to continuous illumination. The root growing medium was made of Turface enriched with a controlled release fertilizer Osmocote. In the course of the flight experiments major parameters of plant cultivation, total level of ISS RM air contamination and plant microbiological status were measured. The grown plants were returned to Earth as fresh or frozen samples. After the three last vegetation cycles the plants were harvested, packed and frozen at -80 0C in the MELFI freezer on the ISS U.S. Module and later returned to Earth onboard Space Shuttle. It was found that the productivity and morphometric (e.g., plant height and mass, number of leaves) parameters of the plants grown in space did not differ from those seen in ground controls. The T coefficient, which represents the total contamination level of ISS air), was 4 (ISS-5), 22 (ISS-17), 55 (ISS-20), 22 (ISS-21) and 28 (ISS-22) versus the norm of no more than 5. In summary, a significant increase in the total contamination level of the ISS RM air did not reduce the productivity of the leaf vegetable plant used in the flight experiments.

  14. Fort Yukon Greenhouse Project

    EPA Pesticide Factsheets

    The Tanana Chiefs Conference is an EPA Climate Showcase Community. EPA’s Climate Showcase Communities Program helps local governments and tribal nations pilot innovative, cost-effective and replicable community-based greenhouse gas reduction projects.

  15. Listeria monocytogenes internalizes in Romaine Lettuce grown in greenhouse conditions

    USDA-ARS?s Scientific Manuscript database

    Listeria monocytogenes has been implicated in a number of outbreaks involving fresh produce, including an outbreak in 2016 resulting from contaminated packaged salads. The persistence and internalization potential of L. monocytogenes in romaine lettuce was evaluated, and the persistence of two L. mo...

  16. Greenhouse gas fluxes from no-till rotated corn in the Upper Midwest

    USDA-ARS?s Scientific Manuscript database

    We determined soil surface fluxes of greenhouse gases (carbon dioxide, nitrous oxide, methane) from no-till, dryland corn (Zea mays L.) in eastern South Dakota and tested the effect of rotation on greenhouse gas fluxes from corn. The corn was grown within a randomized, complete block study that incl...

  17. Solar greenhouses in Minnesota

    SciTech Connect

    Polich, M.

    1981-12-01

    After a discussion of solar greenhouse phenomena and the potential for heat collection and food production, design recommendations are provided for attached heat collecting solar sunspaces and for attached food producing solar greenhouses. Also, design of a single solar structure to maximize heat collection and food production is considered. A method of predicting the performance for attached heat collecting solar sunspaces is given in which the solar savings fraction is calculated. (LEW)

  18. Operating and Maintaining the Greenhouse.

    ERIC Educational Resources Information Center

    Gresser, Priscilla A.

    This learning guide is designed to assist vocational agriculture students in mastering 20 tasks involved in the operation and maintenance of a greenhouse. Addressed in the individual sections of the guide are the following topics: identification of greenhouse designs, greenhouse construction, basic greenhouse maintenance to conserve energy,…

  19. Greenhouse Management Curriculum Guide for Vocational Agriculture/Agribusiness. Curriculum Development. Bulletin No. 1824.

    ERIC Educational Resources Information Center

    University of Southwestern Louisiana, Lafayette.

    This document contains teacher's materials for an 8-unit course in greenhouse management for 11th and 12th graders. The units are as follows: Producing Annual Bedding Plants; Foliage Plants; General Greenhouse Management; Poinsettia Production; Vegetable Bedding Plant Production: Tomatoes, Peppers, and Eggplants; Production of Potted…

  20. Greenhouse Management Curriculum Guide for Vocational Agriculture/Agribusiness. Curriculum Development. Bulletin No. 1824.

    ERIC Educational Resources Information Center

    University of Southwestern Louisiana, Lafayette.

    This document contains teacher's materials for an 8-unit course in greenhouse management for 11th and 12th graders. The units are as follows: Producing Annual Bedding Plants; Foliage Plants; General Greenhouse Management; Poinsettia Production; Vegetable Bedding Plant Production: Tomatoes, Peppers, and Eggplants; Production of Potted…

  1. First report of cucumber green mottle mosaic virus infecting greenhouse cucumber in Canada

    USDA-ARS?s Scientific Manuscript database

    Cucumber green mottle mosaic virus (CGMMV), in the genus Tobamovirus and family Virgaviridae, is a seed-borne pathogen on cucurbits. In early 2013, serious viral disease outbreaks on greenhouse cucumber crops were experienced by greenhouse vegetable growers in Alberta, Canada. CGMMV was detected i...

  2. Assessing the health risk of heavy metals in vegetables to the general population in Beijing, China.

    PubMed

    Song, Bo; Lei, Mei; Chen, Tongbin; Zheng, Yuanming; Xie, Yunfeng; Li, Xiaoyan; Gao, Ding

    2009-01-01

    A systematic survey of As, Cd, Cr, Cu, Ni, Pb and Zn concentrations in vegetables from 416 samples (involving 100 varieties) in Beijing was carried out for assessing the potential health risk to local inhabitants. The results indicated that the metal concentrations in vegetables ranged from < 0.001 to 0.479 microg/g fresh weight (fw) (As), < 0.001 to 0.101 microg/g fw (Cd), < 0.001 to 1.04 microg/g fw (Cr), 0.024 to 8.25 microg/g fw (Cu), 0.001 to 1.689 microg/g fw (Ni), < 0.001 to 0.655 microg/g fw (Pb) and 0.01 to 25.6 microg/g fw (Zn), with average concentrations of 0.013, 0.010, 0.023, 0.51, 0.053, 0.046 and 2.55 microg/g fw, respectively. The results showed that the concentrations of As, Cr, Cu, Cd, Pb and Ni in vegetables from open-fields were all significantly higher than those grown in greenhouses. In addition, in local-produced vegetables, all HMs except Zn were significantly higher than those in provincial vegetables. The estimated daily intake (EDI) of As, Cd, Cr, Cu, Ni, Pb and Zn from vegetables was 0.080, 0.062, 0.142, 3.14, 0.327, 0.283 and 15.7 microg/(kg body weight (bw) x d) for adults, respectively. Arsenic was the major risk contributor for inhabitants since the target hazard quotient based on the weighted average concentration (THQw) of arsenic amounted to 44.3% of the total THQ (TTHQ) value according to average vegetable consumption. The TTHQ was lower than 1 for all age groups, indicating that it was still safe for the general population of Beijing to consume vegetables.

  3. Culture of the Tomato Micro-Tom Cultivar in Greenhouse.

    PubMed

    Rothan, Christophe; Just, Daniel; Fernandez, Lucie; Atienza, Isabelle; Ballias, Patricia; Lemaire-Chamley, Martine

    2016-01-01

    Micro-Tom tomato cultivar is particularly adapted to the development of genomic approaches in tomato. Here, we describe the culture of this plant in greenhouse, including climate regulation, seed sowing and watering, vegetative development, plant maintenance, including treatment of phytosanitary problems, and reproductive development.

  4. [Soils salinity content of greenhouse in Shanghai suburb].

    PubMed

    Yao, Chun-Xia; Chen, Zhen-Lou; Xu, Shi-Yuan

    2007-06-01

    Salinity content and characteristic of farmland soil in Shanghai suburb was studied. Result indicates that soils in greenhouse in Shanghai suburb are partially salted. Soils of suburb where melons or vegetables grow in Shanghai city, 88.52% soil is non-salted while 10.37% mildly salted, 0.74% obviously salted and 0.37% badly salted. Anions component of salt salinity in soil are mainly SO4(2-), Cl-, NO3(-) and cations component are mainly Ca2+, Na+, Mg2+, K+. These ions are mostly from fertilizer auxiliary component or fertilizer transformation component besides some original deposition in soil. The formation of soil secondary salted in greenhouse cultivation in suburbs of Shanghai has a close relationship with improper fertilization or employing too much fertilizer. Soil salinity is different with different cultivation mode and utilization time. From high to low, sequence of soil salinity content in 0 - 20 cm cultivation layer of different crop mode is greenhouse vegetable soil, melon soil, vegetable melon rotation soil and hypaethral vegetable soil respectively. In the same region, salinity in greenhouse soil continually increases and accumulates from underlayer to surface along with more utilization years.

  5. Optimization of lamp spectrum for vegetable growth

    NASA Technical Reports Server (NTRS)

    Prikupets, L. B.; Tikhomirov, A. A.

    1994-01-01

    An increase in the demand for and production of vegetables in the winter, mainly in northern and Siberian regions, inevitably leads to mass building of structures for growing plants under completely artificial conditions. An industrial lighting technology is required whose main parameters (spectrum, irradiance, photoperiod) should be assigned carefully and should uniquely determine, along with other important characteristics of the artificial climate, the productivity of the plant-production facility. The most widespread crops grown in our country under indoor conditions are cucumber and tomato plants, which account for more than 98% of the area in greenhouses. These plants are good prospects for growing completely under intense artificial lighting conditions (photocultures). Optimization of the main parameters of optical radiation when growing these plants is the most important task of achieving their profitable production. At present, considerable experience has been gained in studying the dependence of productivity of cucumber and tomato communities on irradiation conditions. Fundamental studies of the Agrophysical Research Institute of the Russian Academy of Sciences, Timiryazev Institute of Plant Physiology of the Russian Academy of Sciences, Timiryazev Agricultural Academy, and other institutes create a good basis for a detailed study of the given problem. Commercial sources of radiation substantially differing in spectral characteristics in the region of photosynthetically active radiation (PAR) were used in the studies.

  6. Passive solar renovation of an existing commercial greenhouse

    SciTech Connect

    McGinnis, J.W.; Whitehead, N.

    1980-01-01

    The renovation of an existing 1800 square foot commercial greenhouse to incorporate passive solar reliant and energy conserving features is detailed. The Aquatic-Agriculture Institute for Research, a non-profit group, sponsored the project to develop efficient production methods to raise vegetables and fish at the community level. The performance of the remodeled greenhouse will be compared to the performance of the same greenhouse as it was originally designed. The restored greenhouse began operation in September 1979. Accurate fuel and temperature records maintained through-out the past winter, show the cost of back-up heating under operating conditions to be approximately $150.00. Old fuel receipts dating back into the 1940's show an average use of 2000 gallons of heating fuel each winter prior to remodeling. This would indicate a yearly fuel savings of better than 90% through the use of passive solar techniques.

  7. 15. Interior view, greenhouse, from the northwest. The greenhouse interior ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    15. Interior view, greenhouse, from the northwest. The greenhouse interior was quite modest, the space between the floor of the lower level and the joists carrying the loft floor is only five-and-one-half feet. - John Bartram House & Garden, Greenhouse, 54th Street & LIndbergh Boulevard, Philadelphia, Philadelphia County, PA

  8. Greenhouse Gas Court Decision

    EPA Pesticide Factsheets

    View the June 26, 2012, U.S. Court of Appeals- D.C. Circuit's decision to uphold EPA's Endangerment Finding and greenhouse gas regulations issued under the Clean Air Act (CAA) for passenger vehicles and CAA permitting for stationary sources.

  9. Application Problem of Biomass Combustion in Greenhouses for Crop Production

    NASA Astrophysics Data System (ADS)

    Kawamura, Atsuhiro; Akisawa, Atsushi; Kashiwagi, Takao

    It is consumed much energy in fossil fuels to production crops in greenhouses in Japan. And fl ue gas as CO2 fertilization is used for growing crops in modern greenhouses. If biomass as renewable energy can use for production vegetables in greenhouses, more than 800,000 kl of energy a year (in crude oil equivalent) will be saved. In this study, at fi rst, we made the biomass combustion equipment, and performed fundamental examination for various pellet fuel. We performed the examination that considered an application to a real greenhouse next. We considered biomass as both a source of energy and CO2 gas for greenhouses, and the following fi ndings were obtained: 1) Based on the standard of CO2 gas fertilization to greenhouses, it is diffi cult to apply biomass as a CO2 fertilizer, so that biomass should be applied to energy use only, at least for the time being. 2) Practical biomass energy machinery for economy, high reliability and greenhouses satisfying the conservatism that it is easy is necessary. 3) It is necessary to develop crop varieties and cultivation systems requiring less strict environmental control. 4) Disposal of combustion ash occurring abundantly, effective practical use is necessary.

  10. Operation GREENHOUSE-1951. Final report

    SciTech Connect

    Berkhouse, L.; Davis, S.E.; Gladeck, F.R.; Hallowell, J.H.; Jones, C.B.

    1983-06-15

    GREENHOUSE was a four-detonation atmospheric nuclear weapon's test series conducted in the Marshall Islands at Enewetak Atoll in April and May 1951. This is a report of DOD personnel in GREENHOUSE with an emphasis on operational radiological safety.

  11. Microbiological profile of greenhouses in a farm producing hydroponic tomatoes.

    PubMed

    Orozco, Leopoldo; Rico-Romero, Leticia; Escartín, Eduardo F

    2008-01-01

    Produce, including tomatoes, has been implicated in several outbreaks of foodborne illness. A number of the sources of contamination for produce grown in open fields are known. However, as an alternative agricultural system, hydroponic greenhouses are reasonably expected to reduce some of these sources. The objective of the present study was to determine the microbiological profile of tomatoes grown in greenhouses at a Mexican hydroponic farm with a high technological level and sanitary agricultural practices (SAPs) in place. Tomatoes and other materials associated with the farm were analyzed for the presence of Salmonella enterica and populations of Escherichia coli, coliforms, and Enterobacteriaceae. Tomatoes showed median levels of 0.8 log CFU per tomato for Enterobacteriaceae, < 0.5 log CFU per tomato for coliforms, and 0.5 most probable number per tomato for E. coli. Despite the physical barriers that the facilities provide and the implemented SAPs, we found that 2.8% of tomatoes were contaminated with Salmonella and 0.7% with E. coli. Other Salmonella-positive materials were puddles, soil, cleaning cloths, and sponges. Samples from the nursery and greenhouses were positive for E. coli, whereas Salmonella was found only in the latter. Although hydroponic greenhouses provide physical barriers against some sources of enteric bacterial contamination, these results show that sporadic evidence of fecal contamination and the presence of Salmonella can occur at the studied greenhouse farm.

  12. Supplemental photosynthetic lighting for greenhouse tomato production

    SciTech Connect

    Godfriaux, B.L.; Wittman, W.K. ); Janes, H.W.; McAvoy, R.J.; Putman, J.; Logendra, S. . Dept. of Horticulture and Forestry); Mears, D.R.; Giacommelli, G.; Giniger, M. . Dept. of Biological and Agricultural Engineering)

    1989-12-01

    The influence of supplemental light on the growth and productivity of greenhouse tomatoes grown to a single cluster on movable benches is examined, and the economic feasibility of such a system is evaluated. Experiments were conducted to quantify the tomato plants' response to various levels of supplemental light in terms of growth rate and yield at various stages in their development (e.g., seedling, flowering plant, etc.). The 1984--85 experiments showed that supplemental photosynthetic lighting nearly doubled tomato yields, from 0.48 to 0.86 lbs/plant. Subsequent experiments in 1985--86 identified the best tomato varieties for this treatment and further increased yields to 1.3 lbs/plant. In addition, the use of supplemental lighting was found to hasten tomato crop maturity. An economic analysis was performed on the 1985--86 empirical data using the tax rates and provisions then in force. It indicated that a 10-acre greenhouse could provide an after-tax internal rate of return of 10% to 12% using only equity financing. This return could likely be increased to 15--18% with the use of combined debt/equity financing. Using supplemental lighting on 10,000 acres of greenhouse production would require an estimated 7.5 billion kWh of additional electricity per year and, at 4.7 cents/kWh, generate an estimated $350 million in additional utility revenues. 48 refs., 34 figs., 24 tabs.

  13. Vegetative reproduction capacities of floodplain willows--cutting response to competition and biomass loss.

    PubMed

    Radtke, A; Mosner, E; Leyer, I

    2012-03-01

    While several studies on regeneration in Salicaceae have focused on seedling recruitment, little is known about factors controlling their vegetative reproduction. In two greenhouse experiments, we studied the response of floodplain willows (Salix fragilis, S. viminalis, S. triandra) to competition with Poa trivialis, and to shoot and root removal when planted as vegetative cuttings. In the first experiment, growth performance variables were analysed in relation to full competition, shoot competition, root competition and control, taking into account two different water levels. After 9 weeks, shoots were removed and the resprouting capacity of the bare cuttings was recorded. In the second experiment, the cutting performance of the three floodplain and an additional two fen willow species (S. cinerea, S. aurita) was compared when grown in three different soil compositions and with two different water levels. After 9 weeks, shoot and root biomass was removed and the bare cuttings were replanted to test their ability to resprout. Cutting performance and secondary resprouting were negatively affected by full and shoot competition while root competition had no or weak effects. The floodplain species performed better than the fen species in all soil types and water levels. Secondary resprouting capacity was also higher in the floodplain species, which showed an additional strong positive response to the previous waterlogging treatment. The results contribute to understanding of the vegetative regeneration ecology of floodplain willows, and suggest that the use of vegetative plantings in restoration plantings could be an effective strategy for recovering floodplain forests.

  14. Pathogen filtration to control plant disease outbreak in greenhouse production

    NASA Astrophysics Data System (ADS)

    Jeon, Sangho; Krasnow, Charles; Bhalsod, Gemini; Granke, Leah; Harlan, Blair; Hausbeck, Mary; Zhang, Wei

    2016-04-01

    Previous research has been extensively focused on understanding the fate and transport of human microbial pathogens in soil and water environments. However, little is known about the transport of plant pathogens, although these pathogens are often found in irrigation waters and could cause severe crop damage and economical loss. Water mold pathogens including Phytophthora spp. and Pythium spp. are infective to a wide range of vegetable and floriculture crops, and they are primarily harbored in soils and disseminated through water flow. It is challenging to control these pathogens because they often quickly develop resistance to many fungicides. Therefore, this multi-scale study aimed to investigate physical removal of plant pathogens from water by filtration, thus reducing the pathogen exposure risks to crops. In column-scale experiments, we studied controlling factors on the transport and retention of Phytophthora capsici zoospores in saturated columns packed with iron oxide coated-sand and uncoated-sand under varying solution chemistry. Biflagellate zoospores were less retained than encysted zoospores, and lower solution pH and greater iron oxide content increased the retention of encysted zoospores. These results provided insights on environmental dispersal of Phytophthora zoospores in natural soils as well as on developing cost-effective engineered filtration systems for pathogen removal. Using small-scale greenhouse filtration systems, we further investigated the performance of varying filter media (i.e., granular sand, iron oxide coated ceramic porous media, and activated carbon) in mitigating disease outbreaks of Phytophthora and Pythium for greenhouse-grown squash and poinsettia, respectively, in comparison with fungicide treatment. For squash, filtration by iron oxide coated media was more effective in reducing the Phytophthora infection, comparing to sand filtration and fungicide application. For poinsettia, sand filtration performed better in controlling

  15. Grafting effects on vegetable quality

    USDA-ARS?s Scientific Manuscript database

    Vegetable grafting began in the 1920s to control soil-borne disease. It is now a common practice in Asia, parts of Europe, and the Middle East. In Japan and Korea most of the cucurbits and tomatoes (Lycopersicon esculentum Mill.) grown are grafted. This practice is rare in the U.S. and there have...

  16. An Introduction to Greenhouse Production. Second Edition.

    ERIC Educational Resources Information Center

    McMahon, Robert W.

    This student manual is presented in its first revision, providing a current, basic text for those preparing for greenhouse and floriculture work. Its fourteen chapters are: Overview of the Greenhouse Industry; Greenhouse Structures; Controlling the Greenhouse Environment; Greenhouse Equipment and Lighting; Greenhouse Irrigation Systems; Root Media…

  17. (Solar pods (greenhouses))

    SciTech Connect

    Kerr, R.T.

    1985-01-01

    Detailed instructions for the construction of solar pads are presented. The materials necessary for constructing the solar pad are made available in kit form. A list of the materials includes: dome shaped double glazing; end plates and supports; 2 x 4's; a snow support rib; and pressure strips. Assembly of the structure is made easy with an electric drill and simple hand tools. The solar pads resemble miniature greenhouses and are used for year round horticulture. (BCS)

  18. Iron versus the greenhouse

    SciTech Connect

    Monastersky, R.

    1995-09-30

    This paper reports on the possible repercussions of a Pacific Ocean experiment which demonstrated the effects of adding iron to the ocean. The plant growth stimulated was enough to use 350000 kilograms of carbon dioxide from the seawater. If performed on a large scale, fertilization of ocean water could absorb billions of tones of carbon dioxide from the air, enough to slow the rate of greenhouse warming. A variety of opinions are presented in the article.

  19. The greenhouse trap

    SciTech Connect

    Lyman, F.; Mintzer, I.; Courrier, K.; MacKenzie, J.

    1990-01-01

    This book describes evidence of global warming and the contributions of man's activities to the process. The impacts of greenhouse gases on climate and health are discussed and recommendations are made for mitigation of these effects. Changes in fuel use, expansion of carbon sinks through planting of trees, and personal commitments to energy conservation are among these recommendations. Individual chapters were indexed separately for the data base.

  20. Operation GREENHOUSE-1951

    DTIC Science & Technology

    1983-06-15

    potential for exposure of weapon diagnostics participants. 26 Effects Experiments All four GREENHOUSE shots tested new weapon developments. Priorities of...but crawling some of the way. Each round trip took about 15 minutes and was made in a different set of test trousers (Reference 72, p. 10). Th...aboard two VB -29s, and aboard an RB-29 from the Strategic Air Command (SAC). flown in specifically to participate in this S. experiment. The film was

  1. Manipulating Sensory and Phytochemical Profiles of Greenhouse Tomatoes Using Environmentally Relevant Doses of Ultraviolet Radiation.

    PubMed

    Dzakovich, Michael P; Ferruzzi, Mario G; Mitchell, Cary A

    2016-09-14

    Fruits harvested from off-season, greenhouse-grown tomato plants have a poor reputation compared to their in-season, garden-grown counterparts. Presently, there is a gap in knowledge with regard to the role of UV-B radiation (280-315 nm) in determining greenhouse tomato quality. Knowing that UV-B is a powerful elicitor of secondary metabolism and not transmitted through greenhouse glass and some greenhouse plastics, we tested the hypothesis that supplemental UV-B radiation in the greenhouse will impart quality attributes typically associated with garden-grown tomatoes. Environmentally relevant doses of supplemental UV-B radiation did not strongly affect antioxidant compounds of fruits, although the flavonol quercetin-3-O-rutinoside (rutin) significantly increased in response to UV-B. Physicochemical metrics of fruit quality attributes and consumer sensory panels were used to determine if any such differences altered consumer perception of tomato quality. Supplemental UV-A radiation (315-400 nm) pre-harvest treatments enhanced sensory perception of aroma, acidity, and overall approval, suggesting a compelling opportunity to environmentally enhance the flavor of greenhouse-grown tomatoes. The expression of the genes COP1 and HY5 were indicative of adaptation to UV radiation, which explains the lack of marked effects reported in these studies. To our knowledge, these studies represent the first reported use of environmentally relevant doses of UV radiation throughout the reproductive portion of the tomato plant life cycle to positively enhance the sensory and chemical properties of fruits.

  2. ANTIOXIDANT ACTIVITY OF TISSUE CULTURE-RAISED BALLOTA NIGRA L. PLANTS GROWN EX VITRO.

    PubMed

    Makowczyńska, Joanna; Grzegorczyk-KAROLAK, Izabela; Wysokińska, Halina

    2015-01-01

    Antioxidant properties and total phenolic and flavonoid contents were evaluated in methanolic extracts of shoots from Ballota nigra plants initiated in vitro (from nodal explants) and in vivo (from seeds). The plants were grown in greenhouse and in the field, and were analyzed at the vegetative and flowering stages. The shoot extract of wild-grown plants of B. nigra was also investigated. The results indicate that antioxidant potential of the B. nigra extracts seems to be due to their scavenging of free radicals (DPPH assay) and metal reducing (FRAP test), while they were less effective at the prevention of linoleic acid peroxidation (LPO test). The extracts from shoots of in vitro derived plants were found to exhibit the greatest antioxidant properties. The extracts were also characterized by the highest content of phenolic compounds and their level was affected by plant developmental stage. The extracts of shoots collected at the flowering period exhibited higher amounts of phenolics and flavonoids than in the extracts of immature plants. A close correlation between the total phenolic content and flavonoid content and antioxidant activity using the DPPH and FRAP assays was obtained. The results of the present study suggest the use in vitro-derived plants of B. nigra instead of using wild plants for pharmaceutical purposes.

  3. Development of a cost-effective method for nitrate and nitrite determination in leafy plants and nitrate and nitrite contents of some green leafy vegetables grown in the Aegean region of Turkey.

    PubMed

    Ozdestan, Ozgül; Uren, Ali

    2010-05-12

    An accurate, fast, easily applicable, and cost-effective method for the determination of nitrate and nitrite was developed. This method was much more reliable than the cadmium column reduction method, which is a tedious and time-consuming procedure and not easily applicable. The principle of the method was reduction of nitrate to nitrite with cadmium acetate solution and zinc powder and then treatment with Griess reagent. Recovery of the method changed from 92.9 to 102.8%, and detection limit was found as 31.4 mg/kg. Coefficient of variation was 3.16% for intraday precision. Nitrate and nitrite contents of 10 types of leafy vegetables native to the Aegean region of Turkey were determined. Wild radish, chicory, fennel, blessed thistle, blue mallow, and chard were analyzed for the first time. Nitrate contents were found between 354.8 mg/kg for iceberg lettuce and 4653 mg/kg for wild radish. Tested vegetables contained <26.33 mg/kg nitrite.

  4. Micropropagation, Acclimatization, and Greenhouse Culture of Veratrum californicum.

    PubMed

    White, Sarah A; Adelberg, Jeffrey; Naylor-Adelberg, Jacqueline; Mann, David A; Song, Ju Yeon; Sun, Youping

    2016-01-01

    Micropropagation and production of Veratrum californicum is most successful when using a premixed Murishage and Skoog basal medium with vitamins and a 5-week subculture cycle at 16 °C for multiplication. These culture conditions provide the best percent survival after acclimatization in the greenhouse. However, clone response to temperature and light quality within culture conditions varies. Micropropagated plants have mass and morphology similar to 2- or 3-year-old seedlings. Acclimatized plantlets can then be grown in the greenhouse using sub-irrigation (ebb and flood) to maintain substrate volumetric water content > 44 %. Growth cycle in the greenhouse must be about 100 days, followed by dormancy for 5 months at 5 °C.

  5. Characterization of culturable bacterial endophytes and their capacity to promote plant growth from plants grown using organic or conventional practices.

    PubMed

    Xia, Ye; DeBolt, Seth; Dreyer, Jamin; Scott, Delia; Williams, Mark A

    2015-01-01

    Plants have a diverse internal microbial biota that has been shown to have an important influence on a range of plant health attributes. Although these endophytes have been found to be widely occurring, few studies have correlated agricultural production practices with endophyte community structure and function. One agricultural system that focuses on preserving and enhancing soil microbial abundance and biodiversity is organic farming, and numerous studies have shown that organically managed system have increased microbial community characteristics. Herein, the diversity and specificity of culturable bacterial endophytes were evaluated in four vegetable crops: corn, tomato, melon, and pepper grown under organic or conventional practices. Endophytic bacteria were isolated from surface-sterilized shoot, root, and seed tissues and sequence identified. A total of 336 bacterial isolates were identified, and grouped into 32 species and five phyla. Among these, 239 isolates were from organically grown plants and 97 from those grown conventionally. Although a diverse range of bacteria were documented, 186 were from the Phylum Firmicutes, representing 55% of all isolates. Using the Shannon diversity index, we observed a gradation of diversity in tissues, with shoots and roots having a similar value, and seeds having the least diversity. Importantly, endophytic microbial species abundance and diversity was significantly higher in the organically grown plants compared to those grown using conventional practices, potentially indicating that organic management practices may increase endophyte presence and diversity. The impact that these endophytes could have on plant growth and yield was evaluated by reintroducing them into tomato plants in a greenhouse environment. Of the bacterial isolates tested, 61% were found to promote tomato plant growth and 50-64% were shown to enhance biomass accumulation, illustrating their potential agroecosystem application.

  6. Characterization of culturable bacterial endophytes and their capacity to promote plant growth from plants grown using organic or conventional practices

    PubMed Central

    Xia, Ye; DeBolt, Seth; Dreyer, Jamin; Scott, Delia; Williams, Mark A.

    2015-01-01

    Plants have a diverse internal microbial biota that has been shown to have an important influence on a range of plant health attributes. Although these endophytes have been found to be widely occurring, few studies have correlated agricultural production practices with endophyte community structure and function. One agricultural system that focuses on preserving and enhancing soil microbial abundance and biodiversity is organic farming, and numerous studies have shown that organically managed system have increased microbial community characteristics. Herein, the diversity and specificity of culturable bacterial endophytes were evaluated in four vegetable crops: corn, tomato, melon, and pepper grown under organic or conventional practices. Endophytic bacteria were isolated from surface-sterilized shoot, root, and seed tissues and sequence identified. A total of 336 bacterial isolates were identified, and grouped into 32 species and five phyla. Among these, 239 isolates were from organically grown plants and 97 from those grown conventionally. Although a diverse range of bacteria were documented, 186 were from the Phylum Firmicutes, representing 55% of all isolates. Using the Shannon diversity index, we observed a gradation of diversity in tissues, with shoots and roots having a similar value, and seeds having the least diversity. Importantly, endophytic microbial species abundance and diversity was significantly higher in the organically grown plants compared to those grown using conventional practices, potentially indicating that organic management practices may increase endophyte presence and diversity. The impact that these endophytes could have on plant growth and yield was evaluated by reintroducing them into tomato plants in a greenhouse environment. Of the bacterial isolates tested, 61% were found to promote tomato plant growth and 50–64% were shown to enhance biomass accumulation, illustrating their potential agroecosystem application. PMID:26217348

  7. The greenhouse gambit

    SciTech Connect

    Dogan, D. . Environmental Information Service)

    1992-01-01

    While forecasts of the economic costs and benefits of ameliorating global warming remain speculative, so, too, are the climate change projections that gird the debate. The consensus among most of the scientific community is that a doubling of atmospheric carbon dioxide is likely to raise the mean global temperature of the Earth 3 to 8 degrees Fahrenheit by 2050. To put this forecast in some perspective, the planet was about 10 degrees cooler during the last Great Ice Age and about 10 degrees warmer dozing the Age of the Dinsosaurs. Accordingly, the warming could bring about dramatic changes in climate. But a prudent investor must be careful not to invest too much in pat assumptions about the greenhouse effect. The climate may have many surprises in store. Indeed, it has surprised climate forecasters already by not warming nearly as fast as their general circulation models have suggested it would. This book examines four industries with the most at stake in the greenhouse debate: agriculture, forest products, automobiles and electric power. All of these industries essentially face two choices: Act now to blunt the possible momentum of climate change, or wait and see if the basic forecast is correct, accommodating any change as it occurs. These choices involve a trade-off between further information-gathering to ensure a proper course of action and implementing a strategy, quickly to its intended effect. Such a trade-off is the essence of risk, the stuff of investing. For the purposes of this book, it defines the greenhouse gambit.''

  8. Design and development of a greenhouse growing system with a cooling facility using geothermal energy; Part 1

    SciTech Connect

    Tanaka, Shunichiro; Ishibashi, Sadato . Faculty of Agriculture); Kaieda, Masami )

    1994-03-01

    The purpose of the present work was to develop a greenhouse growing system with a night cooling facility using geothermal energy to grow fall and winter vegetables during high summer temperatures. In this paper, the authors first designed and constructed a greenhouse cooling facility using geothermal water for the driving energy, and then conducted a cooling performance test and growth experiment in the growing of vegetables. As a result of the investigation, first, the facility showed the cooling performance as designed, since the air in the greenhouse was cooled to the desired temperature of 15 C. Second, in the open division, almost all the spinach, lettuce, and Kinusaya peas died back during growing and there was therefore no yield. However, in the cooling division, all the vegetables grew normally and their yields were large. From the results mentioned above, the authors concluded that it is possible to grow vegetables during the high-temperature summer season in greenhouse cooled only at night.

  9. A decision support system (GesCoN) for managing fertigation in vegetable crops. Part II—model calibration and validation under different environmental growing conditions on field grown tomato

    PubMed Central

    Conversa, Giulia; Bonasia, Anna; Di Gioia, Francesco; Elia, Antonio

    2015-01-01

    The GesCoN model was evaluated for its capability to simulate growth, nitrogen uptake, and productivity of open field tomato grown under different environmental and cultural conditions. Five datasets collected from experimental trials carried out in Foggia (IT) were used for calibration and 13 datasets collected from trials conducted in Foggia, Perugia (IT), and Florida (USA) were used for validation. The goodness of fitting was performed by comparing the observed and simulated shoot dry weight (SDW) and N crop uptake during crop seasons, total dry weight (TDW), N uptake and fresh yield (TFY). In SDW model calibration, the relative RMSE values fell within the good 10–15% range, percent BIAS (PBIAS) ranged between −11.5 and 7.4%. The Nash-Sutcliffe efficiency (NSE) was very close to the optimal value 1. In the N uptake calibration RRMSE and PBIAS were very low (7%, and −1.78, respectively) and NSE close to 1. The validation of SDW (RRMSE = 16.7%; NSE = 0.96) and N uptake (RRMSE = 16.8%; NSE = 0.96) showed the good accuracy of GesCoN. A model under- or overestimation of the SDW and N uptake occurred when higher or a lower N rates and/or a more or less efficient system were used compared to the calibration trial. The in-season adjustment, using the “SDWcheck” procedure, greatly improved model simulations both in the calibration and in the validation phases. The TFY prediction was quite good except in Florida, where a large overestimation (+16%) was linked to a different harvest index (0.53) compared to the cultivars used for model calibration and validation in Italian areas. The soil water content at the 10–30 cm depth appears to be well-simulated by the software, and the GesCoN proved to be able to adaptively control potential yield and DW accumulation under limited N soil availability scenarios and consequently to modify fertilizer application. The DSSwell simulate SDW accumulation and N uptake of different tomato genotypes grown under Mediterranean and

  10. Occupational asthma in greenhouse workers.

    PubMed

    Monsó, Eduard

    2004-03-01

    A prevalence of asthma over 5% has been reported in flower farmers,and work inside greenhouses has emerged as an additional risk factor. Workplace determinants behind this high prevalence has been examined, and a prevalence of sensitization to workplace allergens over 30% has been reported being pollens, moulds, and Tetranychus urticae allergens the main sensitizers. Bronchial challenge tests in the workplace have demonstrated occupational asthma in more than 20% of the sensitized greenhouse growers. Air contamination inside greenhouses is mainly related to moulds, and is facilitated by the high indoor temperature and humidity. Cladosporium, Penicillium, Aspergillus, and Alternaria and a wide range of flower pollens are able to sensitize the greenhouse worker and cause occupational asthma. Tetranychus urticae have allergens shared with other mites, but the low prevalence of cross-sensitization between them confirm that Tetranychus urticae contains species-specific allergens that may cause respiratory symptoms. Additionally, working inside greenhouses has been related to an increase in the prevalence of chronic bronchitis in nonsmokers. The cultivation of greenhouse crops may cause occupational asthma through sensitization to workplace pollens, moulds, and Tetranychus urticae allergens. In greenhouse flower growers, skin testing identifies sensitization to these allergens in one third of the growers, and more than one fifth of the sensitized workers will develop occupational asthma. Greenhouse work has also been related to chronic bronchitis in nonsmokers, suggesting a causal effect of greenhouse air contaminants on this disease as well.

  11. CO/sub 2/ enrichment in a solar energy collection/storage greenhouse

    SciTech Connect

    Willits, D.H.; Peet, M.M.

    1981-01-01

    The potential of the N.C. State solar energy collection/storage greenhouse to increase the benefits of CO/sub 2/ enrichment in warm climates was investigated. Tomatoes, cucumbers, and bedding plants were grown in this house at 1000 ppm and in a conventional greenhouse unenriched. Yield increases (14.6% for tomatoes, 42.0% for cucumbers, 104% for bedding plants) compare favorably with enrichment studies done in colder climates. 9 refs.

  12. Predicting Greenhouse Gas Emissions and Soil Carbon from Changing Pasture to an Energy Crop

    PubMed Central

    Duval, Benjamin D.; Anderson-Teixeira, Kristina J.; Davis, Sarah C.; Keogh, Cindy; Long, Stephen P.; Parton, William J.; DeLucia, Evan H.

    2013-01-01

    Bioenergy related land use change would likely alter biogeochemical cycles and global greenhouse gas budgets. Energy cane (Saccharum officinarum L.) is a sugarcane variety and an emerging biofuel feedstock for cellulosic bio-ethanol production. It has potential for high yields and can be grown on marginal land, which minimizes competition with grain and vegetable production. The DayCent biogeochemical model was parameterized to infer potential yields of energy cane and how changing land from grazed pasture to energy cane would affect greenhouse gas (CO2, CH4 and N2O) fluxes and soil C pools. The model was used to simulate energy cane production on two soil types in central Florida, nutrient poor Spodosols and organic Histosols. Energy cane was productive on both soil types (yielding 46–76 Mg dry mass⋅ha−1). Yields were maintained through three annual cropping cycles on Histosols but declined with each harvest on Spodosols. Overall, converting pasture to energy cane created a sink for GHGs on Spodosols and reduced the size of the GHG source on Histosols. This change was driven on both soil types by eliminating CH4 emissions from cattle and by the large increase in C uptake by greater biomass production in energy cane relative to pasture. However, the change from pasture to energy cane caused Histosols to lose 4493 g CO2 eq⋅m−2 over 15 years of energy cane production. Cultivation of energy cane on former pasture on Spodosol soils in the southeast US has the potential for high biomass yield and the mitigation of GHG emissions. PMID:23991028

  13. Predicting greenhouse gas emissions and soil carbon from changing pasture to an energy crop.

    PubMed

    Duval, Benjamin D; Anderson-Teixeira, Kristina J; Davis, Sarah C; Keogh, Cindy; Long, Stephen P; Parton, William J; DeLucia, Evan H

    2013-01-01

    Bioenergy related land use change would likely alter biogeochemical cycles and global greenhouse gas budgets. Energy cane (Saccharum officinarum L.) is a sugarcane variety and an emerging biofuel feedstock for cellulosic bio-ethanol production. It has potential for high yields and can be grown on marginal land, which minimizes competition with grain and vegetable production. The DayCent biogeochemical model was parameterized to infer potential yields of energy cane and how changing land from grazed pasture to energy cane would affect greenhouse gas (CO2, CH4 and N2O) fluxes and soil C pools. The model was used to simulate energy cane production on two soil types in central Florida, nutrient poor Spodosols and organic Histosols. Energy cane was productive on both soil types (yielding 46-76 Mg dry mass · ha(-1)). Yields were maintained through three annual cropping cycles on Histosols but declined with each harvest on Spodosols. Overall, converting pasture to energy cane created a sink for GHGs on Spodosols and reduced the size of the GHG source on Histosols. This change was driven on both soil types by eliminating CH4 emissions from cattle and by the large increase in C uptake by greater biomass production in energy cane relative to pasture. However, the change from pasture to energy cane caused Histosols to lose 4493 g CO2 eq · m(-2) over 15 years of energy cane production. Cultivation of energy cane on former pasture on Spodosol soils in the southeast US has the potential for high biomass yield and the mitigation of GHG emissions.

  14. Dynamics of Nitrogen Uptake and Mobilization in Field-grown Winter Oilseed Rape (Brassica napus) From Stem Extension to Harvest. II. An 15N-labelling-based Simulation Model of N Partitioning Between Vegetative and Reproductive Tissues

    PubMed Central

    MALAGOLI, P.; LAINE, P.; ROSSATO, L.; OURRY, A.

    2005-01-01

    • Background and Aims Oilseed rape (Brassica napus) has often been used as a catch crop to deal with the issue of N leaching, but for this to be effective, prediction of the crop's N uptake capability and N partitioning is required. The aim of this work was to build a compartmental model of N dynamics in oilseed rape, based on the kinetic description of N uptake, partitioning and mobilization in each organ. • Model In this study, logistic and exponential equations were fitted to the N relations of each compartment, especially the leaf at each node. Data previously obtained from an 15N-labelling field experiment was used to quantify the partitioning of total N content, the allocation of N taken up and subsequent changes in the sink/source status for endogenous N in each tissue throughout the growth cycle. • Key Results and Conclusions This modelling approach provides a unique tool for the quantitative estimation of cycling of endogenous N in relation to changes in N uptake at the whole-plant level. Furthermore, as oilseed rape is known to release large amounts of N to the soil during spring through leaf loss, this model was used to identify potential methods for improving the N harvest index of the crop. Simulations showed that N content or yield could be improved by 15 % by optimizing N transfer from vegetative to reproductive tissues and by reducing the residual %N (DW) in abscised leaves. PMID:15802311

  15. Dissipation of pyrethroid residues in peppers, zucchinis, and green beans exposed to field treatments in greenhouses: evaluation by decline curves.

    PubMed

    Martinez Galera, Maria; Gil Garcia, Maria D; Rodriguez Lallena, Jose A; Lopez Lopez, Trinidad; Martinez Vidal, Jose L

    2003-09-10

    Dissipation of seven pyrethroid insecticides under field conditions was evaluated on green beans, zucchinis, and peppers grown in experimental greenhouses (Almería, Spain). Pyrethroid residues were determined by high performance liquid chromatography using continuous on-line post-elution photoirradiation with fluorescence detection after dichloromethane extraction and cleanup on florisil phase cartridges. Mathematically defined decline curves were established by determining optimal relationships between pyrethroid residues and time. Different models were used to find these curves. The 1st-order model achieved the best adjustment to the experimental data in 42.9% of cases. The RF (root function) 1st-order model was the best in 33.3% of times. Each of the 1.5th- and 2nd-order models provided the best adjustment in a 9.5% of the cases. Finally, the RF 1.5th-order model was the most appropriate in only 4.8% of cases. Half-life times for these three vegetables were estimated from the optimal models. The preharvest intervals for the residues in these three vegetables was obtained, taking into account the maximum residue levels established by the existing legislation. They were all lower than the ones specified by the makers of commercial formulates, which ensures a safe enough consumption.

  16. Effects of light-emitting diode supplementary lighting on the winter growth of greenhouse plants in the Yangtze River Delta of China.

    PubMed

    Li, Xue; Lu, Wei; Hu, Guyue; Wang, Xiao Chan; Zhang, Yu; Sun, Guo Xiang; Fang, Zhichao

    2016-12-01

    The winter in the Yangtze River Delta area of China involves more than 1 month of continuous low temperature and poor light (CLTL) weather conditions, which impacts horticultural production in an unheated greenhouse; however, few greenhouses in this area are currently equipped with a heating device. The low-cost and long-living light-emitting diode (LED) was used as an artificial light source to explore the effects of supplementary lighting during the dark period in CLTL winter on the vegetative characteristics, early yield, and physiology of flowering for pepper plants grown in a greenhouse without heating. Two LED lighting sets were employed with different light source to provide 65 μmol m(-2) s(-1) at night: (1) LED-A: red LEDs (R, peak wavelength 660 nm) and blue LEDs (B, peak wavelength 460 nm) with an R:B ratio of 6:3; and (2) LED-B: R and B LEDs at an R:B ratio of 8:1. Plants growth parameters and chlorophyll fluorescence characteristics were compared between lighting treatments and the control group. Plants' yield and photosynthesis ability were improved by LED-A. Pepper grown under the LED-A1 strategy showed a 303.3 % greater fresh weight of fruits and a 501.3 % greater dry mass compared with the control group. Plant leaves under LED-A1 showed maximum efficiency of the light quantum yield of PSII, electron transfer rate, and the proportion of the open fraction of PSII centers, with values 113.70, 114.34, and 211.65 % higher than those of the control group, respectively, and showed the lowest rate constant of thermal energy dissipation of all groups. LED-B was beneficial to the plant height and stems diameter of the pepper plants more than LED-A. These results can serve as a guide for environment control and for realizing low energy consumption for products grown in a greenhouse in the winter in Southern China.

  17. Has your greenhouse gone virtual?

    USDA-ARS?s Scientific Manuscript database

    Virtual Grower is a free decision-support software program available from USDA-ARS that allows growers to build a virtual greenhouse. It was initially designed to help greenhouse growers estimate heating costs and conduct simple simulations to figure out where heat savings could be achieved. Featu...

  18. Mars inflatable greenhouse analog.

    PubMed

    Sadler, Philip D; Giacomelli, Gene A

    2002-01-01

    Light intensities on the Martian surface can possibly support a bioregenerative life support system (BLSS) utilizing natural sunlight for hydroponic crop production, if a suitable controlled environment can be provided. Inflatable clear membrane structures offer low mass, are more easily transported than a rigid structure, and are good candidates for providing a suitable controlled environment for crop production. Cable culture is one hydroponic growing system that can take advantage of the beneficial attributes of the inflatable structure. An analog of a Mars inflatable greenhouse can provide researchers data on issues such as crew time requirements for operation, productivity for BLSS, human factors, and much more at a reasonable cost. This is a description of one such design.

  19. The greenhouse of Titan.

    NASA Technical Reports Server (NTRS)

    Sagan, C.

    1973-01-01

    Analysis of non-gray radiative equilibrium and gray convective equilibrium on Titan suggests that a massive molecular-hydrogen greenhouse effect may be responsible for the disagreement between the observed IR temperatures and the equilibrium temperature of an atmosphereless Titan. Calculations of convection indicate a probable minimum optical depth of 14 which corresponds to a molecular hydrogen shell of substantial thickness with total pressures of about 0.1 bar. It is suggested that there is an equilibrium between outgassing and blow-off on the one hand and accretion from the protons trapped in a hypothetical Saturnian magnetic field on the other, in the present atmosphere of Titan. It is believed that an outgassing equivalent to the volatilization of a few kilometers of subsurface ice is required to maintain the present blow-off rate without compensation for all geological time. The presence of an extensive hydrogen corona around Titan is postulated, with surface temperatures up to 200 K.

  20. The MdTFL1 gene of apple (Malus x domestica Borkh.) reduces vegetative growth and generation time.

    PubMed

    Flachowsky, Henryk; Szankowski, Iris; Waidmann, Sascha; Peil, Andreas; Tränkner, Conny; Hanke, Magda-Viola

    2012-10-01

    TFL1 is known as a floral repressor in Arabidopsis thaliana (L.) Heynh. In apple there are two TFL1 homologs, MdTFL1-1 and MdTFL1-2. The MdTFL1-1 gene was silenced in transgenic clones expressing a hairpin gene construct of a 323 bp fragment of MdTFL1-1. The hairpin gene construct was transferred to three different apple genotypes. Of 22 transgenic clones, 21 showed a significant reduction in MdTFL1-1 mRNA expression. Precocious flowering was obtained for 20 clones, which flowered already during in vitro cultivation. Nineteen clones could successfully be transferred to the greenhouse where 18 of them flowered within a few weeks followed by the death or at least a strongly inhibited vegetative growth of the plant. Most of the transgenic flowers developed abnormally. Results obtained on greenhouse-grown plants of the transgenic clones and transgenic seedlings clearly demonstrated the major role of MdTFL1 genes in maintaining the vegetative growth as prerequisite for a perennial lifecycle. It was shown that MdTFL1 dsRNAi promotes a life history similar to annual plants. Preliminary results obtained from grafting experiments with non-transgenic scions grafted onto MdTFL1 dsRNAi transgenic rootstocks indicated that the flower-inducing signal obtained after silencing of MdTFL1 genes seems not to be graft-transmissible.

  1. Pathogenicity of Two Species of Entomopathogenic Nematodes Against the Greenhouse Whitefly, Trialeurodes vaporariorum (Hemiptera: Aleyrodidae), in Laboratory and Greenhouse Experiments.

    PubMed

    Rezaei, Nastaran; Karimi, Javad; Hosseini, Mojtaba; Goldani, Morteza; Campos-Herrera, Raquel

    2015-03-01

    The greenhouse whitefly Trialeurodes vaporariorum (Hemiptera: Aleyrodidae) is a polyphagous pest in greenhouse crops. The efficacy of two entomopathogenic nematodes (EPN), Steinernema feltiae and Heterorhabditis bacteriophora, as biological control agents against T. vaporariorum was evaluated using two model crops typical of vegetable greenhouse productions: cucumber and pepper. Laboratory tests evaluated adults and second nymphal instars for pest susceptibility to different EPN species at different concentrations of infective juveniles (IJ; 0, 25, 50, 100, 150, 200, and 250 IJ per cm(2)); subsequent greenhouse trials against second nymphal instars on cucumber and pepper plants evaluated more natural conditions. Concentrations were applied in combination with Triton X-100 (0.1% v/v), an adjuvant for increasing nematode activity. In laboratory studies, both life stages were susceptible to infection by the two nematode species, but S. feltiae recorded a lower LC50 than H. bacteriophora for both insect stages. Similarly, in greenhouse experiments, S. feltiae required lower concentrations of IJ than H. bacteriophora to reach the same mortality in nymphs. In greenhouse trials, a significant difference was observed in the triple interaction among nematode species × concentration × plant. Furthermore, the highest mortality rate of the second nymphal instars of the T. vaporariorum was obtained from the application of S. feltiae concentrated to 250 IJ/cm(2) on cucumber (49 ± 1.23%). The general mortality caused by nematodes was significantly higher in cucumber than in pepper. These promising results support further investigation for the optimization of the best EPN species/concentration in combination with insecticides or adjuvants to reach a profitable control of this greenhouse pest.

  2. Pathogenicity of Two Species of Entomopathogenic Nematodes Against the Greenhouse Whitefly, Trialeurodes vaporariorum (Hemiptera: Aleyrodidae), in Laboratory and Greenhouse Experiments

    PubMed Central

    Rezaei, Nastaran; Karimi, Javad; Hosseini, Mojtaba; Goldani, Morteza; Campos-Herrera, Raquel

    2015-01-01

    The greenhouse whitefly Trialeurodes vaporariorum (Hemiptera: Aleyrodidae) is a polyphagous pest in greenhouse crops. The efficacy of two entomopathogenic nematodes (EPN), Steinernema feltiae and Heterorhabditis bacteriophora, as biological control agents against T. vaporariorum was evaluated using two model crops typical of vegetable greenhouse productions: cucumber and pepper. Laboratory tests evaluated adults and second nymphal instars for pest susceptibility to different EPN species at different concentrations of infective juveniles (IJ; 0, 25, 50, 100, 150, 200, and 250 IJ per cm2); subsequent greenhouse trials against second nymphal instars on cucumber and pepper plants evaluated more natural conditions. Concentrations were applied in combination with Triton X-100 (0.1% v/v), an adjuvant for increasing nematode activity. In laboratory studies, both life stages were susceptible to infection by the two nematode species, but S. feltiae recorded a lower LC50 than H. bacteriophora for both insect stages. Similarly, in greenhouse experiments, S. feltiae required lower concentrations of IJ than H. bacteriophora to reach the same mortality in nymphs. In greenhouse trials, a significant difference was observed in the triple interaction among nematode species × concentration × plant. Furthermore, the highest mortality rate of the second nymphal instars of the T. vaporariorum was obtained from the application of S. feltiae concentrated to 250 IJ/cm2 on cucumber (49 ± 1.23%). The general mortality caused by nematodes was significantly higher in cucumber than in pepper. These promising results support further investigation for the optimization of the best EPN species/concentration in combination with insecticides or adjuvants to reach a profitable control of this greenhouse pest. PMID:25861117

  3. Veracruz State Preliminary Greenhouse Gases Emissions Inventory

    NASA Astrophysics Data System (ADS)

    Welsh Rodriguez, C.; Rodriquez Viqueira, L.; Guzman Rojas, S.

    2007-05-01

    At recent years, the international organisms such as United Nations, has discussed that the temperature has increased slightly and the pattern of precipitations has changed in different parts of the world, which cause either extreme droughts or floods and that the extreme events have increased. These are some of the risks of global climate change because of the increase of gas concentration in the atmosphere such as carbon dioxides, nitrogen oxides and methane - which increase the greenhouse effect. Facing the consequences that could emerge because of the global temperature grown, there is a genuine necessity in different sectors of reduction the greenhouse gases and reduced the adverse impacts of climate change. To solve that, many worldwide conventions have been realized (Rio de Janeiro, Kyoto, Montreal) where different countries have established political compromises to stabilize their emissions of greenhouse gases. The mitigation and adaptation policies merge as a response to the effects that the global climate change could have, on the humans as well as the environment. That is the reason to provide the analysis of the areas and geographic zones of the country that present major vulnerability to the climate change. The development of an inventory of emissions that identifies and quantifies the principal sources of greenhouse gases of a country, and also of a region is basic to any study about climate change, also to develop specific political programs that allow to preserve and even improve a quality of the atmospheric environment, and maybe to incorporate to international mechanisms such as the emissions market. To estimate emissions in a systematic and consistent way on a regional, national and international level is a requirement to evaluate the feasibility and the cost-benefit of instrumented possible mitigation strategies and to adopt politics and technologies to reduce emissions. Mexico has two national inventories of emissions, 1990 and 1995, now it is

  4. Greenhouse Gas Data Publication Tool

    EPA Pesticide Factsheets

    This tool to gives you access to greenhouse gas data reported to EPA by large facilities and suppliers in the United States through EPA's Greenhouse Gas Reporting Program. The tool allows you to view data in several formats including maps, tables, charts and graphs for individual facilities or groups of facilities. You can search the data set for individual facilities by name or location or filter the data set by state or county, industry sectors and sub-sectors, annual facility emission thresholds, and greenhouse gas type. For more information on the GHG Reporting Program and this data, please visit https://www.epa.gov/ghgreporting

  5. Greenhouse gas trading starts up

    NASA Astrophysics Data System (ADS)

    Showstack, Randy

    While nations decide on whether to sign on to the Kyoto Protocol on climate change, some countries and private companies are moving forward with greenhouse gas emissions trading.A 19 March report, "The Emerging International Greenhouse Gas Market," by the Pew Center on Global Climate Change, reports that about 65 greenhouse gas emissions trades for quantities above 1,000 metric tons of carbon dioxideequivalent already have occurred worldwide since 1996. Many of these trades have taken place under a voluntary, ad hoc framework, though the United Kingdom and Denmark have established their own domestic emissions trading programs.

  6. (Limiting the greenhouse effect)

    SciTech Connect

    Rayner, S.

    1991-01-07

    Traveler attended the Dahlem Research Conference organized by the Freien Universitat, Berlin. The subject of the conference was Limiting the Greenhouse Effect: Options for Controlling Atmospheric CO{sub 2} Accumulation. Like all Dahlem workshops, this was a meeting of scientific experts, although the disciplines represented were broader than usual, ranging across anthropology, economics, international relations, forestry, engineering, and atmospheric chemistry. Participation by scientists from developing countries was limited. The conference was divided into four multidisciplinary working groups. Traveler acted as moderator for Group 3 which examined the question What knowledge is required to tackle the principal social and institutional barriers to reducing CO{sub 2} emissions'' The working rapporteur was Jesse Ausubel of Rockefeller University. Other working groups examined the economic costs, benefits, and technical feasibility of options to reduce emissions per unit of energy service; the options for reducing energy use per unit of GNP; and the significant of linkage between strategies to reduce CO{sub 2} emissions and other goals. Draft reports of the working groups are appended. Overall, the conference identified a number of important research needs in all four areas. It may prove particularly important in bringing the social and institutional research needs relevant to climate change closer to the forefront of the scientific and policy communities than hitherto.

  7. Reducing airborne ectomycorrhizal fungi and growing non-mycorrhizal loblolly pine (Pinus taeda L.) seedlings in a greenhouse.

    PubMed

    Stottlemyer, Aaron D; Wang, G Geoff; Wells, Christina E; Stottlemyer, David W; Waldrop, Thomas A

    2008-07-01

    Atmospheric spores of ectomycorrhizal (ECM) fungi are a potential source of contamination when mycorrhizal studies are performed in the greenhouse, and techniques for minimizing such contamination have rarely been tested. We grew loblolly pine (Pinus taeda L.) from seed in a greenhouse and inside a high-efficiency particulate air-filtered chamber (HFC) constructed within the same greenhouse. Seedlings were germinated in seven different sand- or soil-based and artificially based growth media. Seedlings grown in the HFC had fewer mycorrhizal short roots than those grown in the open greenhouse atmosphere. Furthermore, the proportion of seedlings from the HFC that were completely non-mycorrhizal was higher than that of seedlings from the greenhouse atmosphere. Seedlings grown in sterilized, artificially based growth media (>50% peat moss, vermiculite, and/or perlite by volume) had fewer mycorrhizal short roots than those grown in sand- or soil-based media. The HFC described here can minimize undesirable ECM colonization of host seedlings in greenhouse bioassays. In addition, the number of non-mycorrhizal seedlings can be maximized when the HFC is used in combination with artificially based growth media.

  8. Overview of global greenhouse effects

    SciTech Connect

    Reck, R.A.

    1993-09-01

    This report reviews the factors that influence the evolution of climate and climate change. Recent studies have confirmed that CO{sub 2}, O{sub 3}, N{sub 2}O, CH{sub 4}, and chlorofluorocarbos are increasing in abundance in the atmosphere and can alter the radiation balance by means of the so-called greenhouse effect. The greenhouse effect is as well-accepted phenomenon, but the prediction of its consequences is much less certain. Attempts to detect a human-caused temperature change are still inconclusive. This report presents a discussion of the scientific basis for the greenhouse effect, its relationship to the abundances of greenhouse gases, and the evidence confirming the increases in the abundances. The basis for climate modeling is presented together with an example of the model outputs from one of the most sophisticated modeling efforts. Uncertainties in the present understanding of climate are outlined.

  9. Policy implications of greenhouse warming

    NASA Astrophysics Data System (ADS)

    Coppock, Rob

    1992-03-01

    A study panel of the National Academy of Sciences, National Academy of Engineering, and Institute of Medicine recently issued the report Policy Implications of Greenhouse Warming. That report examined relevant scientific knowldeg and evidence about the potential of greenhouse warming, and assayed actions that could slow the onset of warming (mitigation policies) or help human and natural systems of plants and animals adapt to climatic changes (adaptation policies). The panel found that, even given the considerable uncertainties knowledge of the relevant phenomena, greenhouse warming poses a threat sufficient to merit prompt action. People in this country could probably adapt to the changes likely to accompany greenhouse warming. The costs, however, could be substantial. Investment in mitigation acts as insurance protection against the great uncertainties and the possibility of dramatic surprises. The panel found mitigation options that could reduce U.S. emissions by an estimated 10 to 40 percent at modest cost.

  10. Climate science: Agricultural greenhouse gases

    NASA Astrophysics Data System (ADS)

    Pollock, Chris

    2011-05-01

    Mitigating greenhouse gas emissions from agriculture is important and achievable. However, cutting emissions to meet the UK's legal targets for 2050 will bring technical and political challenges, and may affect food production.

  11. Field trials measuring the effects of ultraviolet-absorbing greenhouse plastic films on insect populations.

    PubMed

    Costa, H S; Robb, K L; Wilen, C A

    2002-02-01

    Field studies were conducted to compare insect population levels in greenhouse crops covered with plastics that block the transmission of UV light in two wavelength ranges. Crops grown in greenhouses under a plastic that blocked UV light at wavelengths of 380 nm and below had lower numbers of aphids and thrips compared with a plastic that blocked UV light at wavelengths of 360 nm and below. This is consistent with the results found for thrips in previous studies using small, completely enclosed tunnels with no plant material. The effects were not as dramatic in the commercial greenhouses, perhaps due to unfiltered light entering through the open sides of those greenhouses. There was no reduction in greenhouse whitefly, Trialeurodes vaporariorum Westwood, populations under the <380 UV-absorbing plastic compared to <360 nm UV-absorbing plastic in these field trials. This is inconsistent with results found in small, completely enclosed tunnels, where sticky traps caught a significantly higher proportion (95 +/- 2%) of released greenhouse whiteflies inside tunnels covered with <360 nm absorbing plastic compared with the <380 nm absorbing plastic. The results of these studies suggest that the type of greenhouse plastic used in a structure can affect population levels of some insect species, and may be useful tools in developing integrated pest management programs for insect management. The design of the greenhouse and amount of unfiltered light that enters the system appear to be important factors in determining the level of effect.

  12. European greenhouse gas fluxes from land use: the impact of expanding the use of dedicated bioenergy crops.

    NASA Astrophysics Data System (ADS)

    Hastings, Astley; Böttcher, Hannes; Clifton-Brown, John; Fuchs, Richard; Hillier, Jon; Jones, Ed; Obersteiner, Michael; Pogson, Mark; Richards, Mark; Smith, Pete

    2013-04-01

    Bioenergy derived from vegetation cycles carbon to and from the atmosphere using the chemical energy fixed by the plants by photosynthesis using solar energy. However bioenergy is not carbon neutral as energy is used and greenhouse gasses (GHG) are emitted in the process of growing bioenergy feeedstocks and processing them into a usable fuel, whether it is biomass or liquid fuel such as biodiesel or bioethanol. Using bio instead of fossil fuels replaces greenhouse gas emissions from coal, oil and gas by those of the biofuel. To estimate the impact on European greenhouse gas fluxes of expanding the use of bioenergy, it is necessary to quantify the difference between the GHG emissions associated with producing and using the biofuel and the fossil fuel it replaces, and to take into account any emissions associated with the change from the original land use to that of growing the bioenergy feedstock. This involves estimating any displacement of food, fibre and timber production to other geographical areas. Here we report on a study of the GHG emissions from the potential increasing use of a variety of biofuels produced from feedstocks grown in the EU countries. The GHG emissions of the historical land use of EU27 have been modelled using ECOSSE on a 1 km grid to estimate the impact the agriculture intensification and land use change of the last 50 years and the associated crop yield gains. The excess land made available from the yield gains is considered to be available for use for bioenergy, and the yields of potential bioenergy feedstocks are estimated from EUROSTAT data or modelled using the bioenergy crop growth model MISCANFOR. These yields are used to calculate the energy used and GHG emissions associated with the use of the resulting biofuel using a life cycle analysis, and to estimate the organic matter input into the soil. The ECOSSE model is then used to estimate the soil carbon change and GHG emissions associated with the land use change to growing the

  13. Greenhouses and their humanizing synergies

    NASA Astrophysics Data System (ADS)

    Haeuplik-Meusburger, Sandra; Paterson, Carrie; Schubert, Daniel; Zabel, Paul

    2014-03-01

    Greenhouses in space will require advanced technical systems of automatic watering, soil-less cultivation, artificial lighting, and computerized observation of plants. Functions discussed for plants in space habitats include physical/health requirements and human psychology, social cohesion, as well as the complex sensorial benefits of plants for humans. The authors consider the role of plants in long-term space missions historically since 1971 (Salyut 1) and propose a set of priorities to be considered within the design requirements for greenhouses and constructed environments given a range of benefits associated with plant-human relationships. They cite recent research into the use of greenhouses in extreme environments to reveal the relative importance of greenhouses for people living in isolated locations. Additionally, they put forward hypotheses about where greenhouses might factor into several strata of human health. In a recent design-in-use study of astronauts' experiences in space habitats discussed in Architecture for Astronauts (Springer Press 2011) it was found that besides the basic advantages for life support there are clearly additional "side benefits" for habitability and physical wellbeing, and thus long-term mission success. The authors have composed several key theses regarding the need to promote plant-human relationships in space, including areas where synergy and symbiosis occur. They cite new comprehensive research into the early US Space Program to reveal where programmatic requirements could be added to space architecture to increase the less quantifiable benefits to astronauts of art, recreation, and poetic engagement with their existential condition of estrangement from the planet. Specifically in terms of the technological requirements, the authors propose the integration of a new greenhouse subsystem component into space greenhouses—the Mobile Plant Cultivation Subsystem—a portable, personal greenhouse that can be integrated

  14. Greenhouse Earth: A Traveling Exhibition

    SciTech Connect

    Booth, W.H.; Caesar, S.

    1992-09-01

    The Franklin Institute Science Museum provided an exhibit entitled the Greenhouse Earth: A Traveling Exhibition. This 3500 square-foot exhibit on global climate change was developed in collaboration with the Association of Science-Technology Centers. The exhibit opened at The Franklin Institute on February 14, 1992, welcoming 291,000 visitors over its three-month stay. During its three-year tour, Greenhouse Earth will travel to ten US cities, reaching two million visitors. Greenhouse Earth aims to deepen public understanding of the scientific issues of global warming and the conservation measures that can be taken to slow its effects. The exhibit features hands-on exhibitry, interactive computer programs and videos, a theater production, a demonstration cart,'' guided tours, and lectures. supplemental educational programs at the Institute included a teachers preview, a symposium on climate change, and a satellite field trip.'' The development of Greenhouse Earth included front-end and formative evaluation procedures. Evaluation includes interviews with visitors, prototypes, and summative surveys for participating museums. During its stay in Philadelphia, Greenhouse Earth was covered by the local and national press, with reviews in print and broadcast media. Greenhouse Earth is the first large-scale museum exhibit to address global climate change.

  15. Midwestern Greenhouse Gas Reduction Accord

    SciTech Connect

    2007-07-01

    The Midwestern Greenhouse Gas Reduction Acccord, or Midwestern Greenhouse gas Accord (MGA), is a regional agreement by governors of the states in the US Midwest and one Canadian province to reduce greenhouse gas emissions to combat climate change. Signatories to the accord include the US states of Minnesota, Wisconsin, Illinois, Indiana, Iowa, Michigan, Kansas, Ohio and South Dakota, and the Canadian Province of Manitoba. The accord, signed on November 15, 2007, established the Midwestern Greenhouse Gas Reduction Program, which aims to: establish greenhouse gas reduction targets and timeframes consistent with MGA member states' targets; develop a market-based and multi-sector cap-and-trade mechanism to help achieve those reduction targets; establish a system to enable tracking, management, and crediting for entities that reduce greenhouse gas emissions; and develop and implement additional steps as needed to achieve the reduction targets, such as a low-carbon fuel standards and regional incentives and funding mechanisms. The GHG registry will be managed by the Climate Registry, which manages the registry for other US state schemes. One of the first actions was to convene an Energy Security under Climate Stewardship Platform to guide future development of the Midwest's energy economy.

  16. Recent Greenhouse Gas Concentrations

    DOE Data Explorer

    Blasing, T. J.

    2016-01-01

    Gases typically measured in parts per million (ppm), parts per billion (ppb) or parts per trillion (ppt) are presented separately to facilitate comparison of numbers. Global Warming Potentials (GWPs) and atmospheric lifetimes are from the Intergovernmental Panel on Climate Change (IPCC, 2013, Table 8.A.1), except for the atmospheric lifetime of carbon dioxide (CO2) which is explained in footnote 4. Additional material on greenhouse gases can be found in CDIAC's Reference Tools. To find out how CFCs, HFCs, HCFCs, and halons are named, see Name that compound: The numbers game for CFCs, HFCs, HCFCs, and Halons. Concentrations given apply to the lower 75-80 percent of the atmosphere, known as the troposphere. Sources of the current and preindustrial concentrations of the atmospheric gases listed in the table below are given in the footnotes. Investigators at the National Oceanic and Atmospheric Administration have provided the recent concentrations. Much of the data provided results from the work of various investigators at institutions other than CDIAC, and represent considerable effort on their part. We ask as a basic professional courtesy that you acknowledge the primary sources, indicated in the footnotes below, or in the links given in the footnotes. Concentrations of ozone and water vapor are spatially and temporally variable due to their short atmospheric lifetimes. A vertically and horizontally averaged water vapor concentration is about 5,000 ppm. Globally averaged water vapor concentration is difficult to measure precisely because it varies from one place to another and from one season to the next. This precludes a precise determination of changes in water vapor since pre-industrial time. However, a warmer atmosphere will likely contain more water vapor than at present. For a more detailed statement on water vapor from the National Oceanic and Atmospheric Administration, see the "water vapor" page at http://lwf.ncdc.noaa.gov/oa/climate/gases.html

  17. Potato (Solanum tuberosum) greenhouse tuber production as an assay for asexual reproduction effects from herbicides

    EPA Science Inventory

    The present study determined whether young potato plants can be used as an assay to indicate potential effects of pesticides on asexual reproduction. Solanum tuberosum (Russet Burbank) plants were grown from seed pieces in a mineral soil in pots under greenhouse conditions. Plant...

  18. Potato (Solanum tuberosum) greenhouse tuber production as an assay for asexual reproduction effects from herbicides

    EPA Science Inventory

    The present study determined whether young potato plants can be used as an assay to indicate potential effects of pesticides on asexual reproduction. Solanum tuberosum (Russet Burbank) plants were grown from seed pieces in a mineral soil in pots under greenhouse conditions. Plant...

  19. Reducing greenhouse gas emissions, water use and grain arsenic levels in rice systems

    USDA-ARS?s Scientific Manuscript database

    Agriculture is faced with the challenge of providing healthy food for a growing population while minimizing environmental consequences. Rice (Oryza sativa), the staple crop for the largest number of people on earth, is grown under flooded soil conditions and uses more water and has higher greenhous...

  20. Milled Paulownia tomentosa as a substrate component in greenhouse annual production

    USDA-ARS?s Scientific Manuscript database

    Recent research has indicated the potential of wood fiber products as alternative substrate components. This study was conducted to determine the effects of Paulowinia tomentosa amended substrates on production of greenhouse grown annuals. Paulownia (PT) was used alone (100% PT) and combined with di...

  1. Soil Phosphorus Level Adequate for Growth of Ocala Sand Pine Seedlings, A Greenhouse Evaluation

    Treesearch

    James B. Baker; R. H. Brendemuehl

    1972-01-01

    A greenhouse study was conducted to determine the level of soil P adequate for satisfactory growth of Ocala sand pine (Pinus clausa (Chapm.) Vasey) seedlings. Various quantities of Lakeland sand with low and high P contents were blended to provide soil mixtures with a range of available P. Ocala sand pine seedlings were grown in these mixtures for 10...

  2. Trace metal accumulation in soil and their phytoavailability as affected by greenhouse types in north China.

    PubMed

    Yang, Lanqin; Huang, Biao; Mao, Mingcui; Yao, Lipeng; Hickethier, Martina; Hu, Wenyou

    2015-05-01

    Long-term heavy organic fertilizer application has linked greenhouse vegetable production (GVP) with trace metal contamination in north China. Given that trace metals release from fertilizers and their availability may be affected by discrepant environmental conditions, especially temperature under different greenhouses, this study investigated Cd, Cu, Pb, and Zn accumulation and contamination extent in soil as well as their phytoavailability under two major greenhouses in Tongshan, north China, namely solar greenhouse (SG) and round-arched plastic greenhouse (RAPG), to evaluate their presumed difference. The results showed significant Cd, Cu, Pb, and Zn accumulation in GVP soil by comparing with those in open-field soil, but their accumulation extent and rates were generally greater in SG than those in RAPG. This may be related to more release of trace metals to soil due to the acceleration of decomposition and humification process of organic fertilizers under higher soil temperature in SG relative to that in RAPG. Overall, soil in both greenhouses was generally less polluted or moderately polluted by the study metals. Similarly, decreased soil pH and elevated soil available metals in SG caused higher trace metals in leaf vegetables in SG than those in RAPG, although there was no obvious risk via vegetable consumption under both greenhouses. Lower soil pH may be predominantly ascribed to more intensive farming practices in SG while elevated soil available metals may be attributed to more release of dissolved organic matter-metal complexes from soil under higher temperature in SG. The data provided in this study may assist in developing reasonable and sustainable fertilization strategies to abate trace metal contamination in both greenhouses.

  3. Understory vegetation

    Treesearch

    Steve Sutherland; Todd F. Hutchinson; Jennifer L. Windus

    2003-01-01

    This chapter documents patterns of species composition and diversity within the understory vegetation layer and provides a species list for the four study areas in southern Ohio. Within each of 108 plots, we recorded the frequency of all vascular plant species in sixteen 2-m² quadrats. We recorded 297 species, including 187 forbs (176 perennials, 9 annuals, 2...

  4. Fermented Vegetables

    USDA-ARS?s Scientific Manuscript database

    The wide variety of fermented foods of the world can be classified by the materials obtained from the fermentation, such as alcohol (beer, wine), organic acid such as lactic acid and acetic acid (vegetables, dairy), carbon dioxide (bread), and amino acids or peptides from protein (fish fermentations...

  5. Vegetation dynamics

    Treesearch

    Sammy L. King; Marianne K. Burke; Terry J. Antrobus; Sarah Billups

    2000-01-01

    A disturbance can be defined as "any relatively discrete event in time that disrupts ecosystem, community, or population structure and changes resources, substrate availability, or the physical environment" (Pickett and White 1985). Vegetation dynamics are a function of the temporal and spatial patterns of the disturbance regime. Natural disturbance regimes...

  6. Vegetative regeneration

    Treesearch

    George A. Schier; John R. Jones; Robert P. Winokur

    1985-01-01

    Aspen is noted for its ability to regenerate vegetatively by adventitious shoots or suckers that arise on its long lateral roots. It also produces sprouts from stumps and root collars; but they are not common. In a survey of regeneration after clearcutting mature aspen in Utah. Baker (1918b) found that 92% of the shoots originated from roots, 7% from root collars, and...

  7. Nitrogen isotopic signature of vegetables from the Slovenian market and its suitability as an indicator of organic production.

    PubMed

    Sturm, Martina; Lojen, Sonja

    2011-06-01

    The aim of this study was to obtain preliminary data on δ(15)N values in organically and conventionally grown vegetables available on the Slovenian market to determine whether there are any characteristic differences in δ(15)N values, which could be used as a marker to differentiate between organically and conventionally grown vegetables, namely vegetables grown with synthetic or organic nitrogen fertilisers. Therefore, 14 different varieties of organically and conventionally grown vegetables were analysed. The results obtained show clear differences in mean δ(15)N values between organically and conventionally grown vegetables (up to 6.3\\permil). However, due to overlapping results, it was not possible to differentiate between organically and conventionally grown counterparts in eight vegetable varieties, despite the differences in mean δ(15)N values. The results obtained indicate that the method has several limitations. Hence, δ(15)N could be a reliable indicator for organic production, but nevertheless, the conclusion has to be validated by background information.

  8. The Greenhouse and Anti-Greenhouse Effects on Titan

    NASA Technical Reports Server (NTRS)

    McKay, C. P.; Cuzzi, Jeffrey N. (Technical Monitor)

    1994-01-01

    Titan is the largest moon of Saturn and is the only moon in the solar system with a substantial atmosphere. Its atmosphere is mostly made of nitrogen, with a few percent CH4, 0.1% H2 and an uncertain level of Ar (less than 10%). The surface pressure is 1.5 atms and the surface temperature is 95 K, decreasing to 71 at the tropopause before rising to stratospheric temperatures of 180 K. In pressure and composition Titan's atmosphere is the closest twin to Earth's. The surface of Titan remains unknown, hidden by the thick smog layer, but it may be an ocean of liquid methane and ethane. Titan's atmosphere has a greenhouse effect which is much stronger than the Earth's - 92% of the surface warming is due to greenhouse radiation. However an organic smog layer in the upper atmosphere produces an anti-greenhouse effect that cuts the greenhouse warming in half - removing 35% of the incoming solar radiation. Models suggest that during its formation Titan's atmosphere was heated to high temperatures due to accretional energy. This was followed by a cold Triton-like period which gradually warmed to the present conditions. The coupled greenhouse and haze anti-greenhouse may be relevant to recent suggestions for haze shielding of a CH4 - NH3 early atmosphere on Earth or Mars. When the NASA/ESA mission to the Saturn System, Cassini, launches in a few years it will carry a probe that will be sent to the surface of Titan and show us this world that is strange and yet in many ways similar to our own.

  9. The Greenhouse and Anti-Greenhouse Effects on Titan

    NASA Technical Reports Server (NTRS)

    McKay, C. P.; Cuzzi, Jeffrey N. (Technical Monitor)

    1994-01-01

    Titan is the largest moon of Saturn and is the only moon in the solar system with a substantial atmosphere. Its atmosphere is mostly made of nitrogen, with a few percent CH4, 0.1% H2 and an uncertain level of Ar (less than 10%). The surface pressure is 1.5 atms and the surface temperature is 95 K, decreasing to 71 at the tropopause before rising to stratospheric temperatures of 180 K. In pressure and composition Titan's atmosphere is the closest twin to Earth's. The surface of Titan remains unknown, hidden by the thick smog layer, but it may be an ocean of liquid methane and ethane. Titan's atmosphere has a greenhouse effect which is much stronger than the Earth's - 92% of the surface warming is due to greenhouse radiation. However an organic smog layer in the upper atmosphere produces an anti-greenhouse effect that cuts the greenhouse warming in half - removing 35% of the incoming solar radiation. Models suggest that during its formation Titan's atmosphere was heated to high temperatures due to accretional energy. This was followed by a cold Triton-like period which gradually warmed to the present conditions. The coupled greenhouse and haze anti-greenhouse may be relevant to recent suggestions for haze shielding of a CH4 - NH3 early atmosphere on Earth or Mars. When the NASA/ESA mission to the Saturn System, Cassini, launches in a few years it will carry a probe that will be sent to the surface of Titan and show us this world that is strange and yet in many ways similar to our own.

  10. Kinetic study of phytotoxicity induced by foliar lead uptake for vegetables exposed to fine particles and implications for sustainable urban agriculture.

    PubMed

    Xiong, TianTian; Austruy, Annabelle; Pierart, Antoine; Shahid, Muhammad; Schreck, Eva; Mombo, Stéphane; Dumat, Camille

    2016-08-01

    At the global scale, foliar metal transfer occurs for consumed vegetables cultivated in numerous urban or industrial areas with a polluted atmosphere. However, the kinetics of metal uptake, translocation and involved phytotoxicity was never jointly studied with vegetables exposed to micronic and sub-micronic particles (PM). Different leafy vegetables (lettuces and cabbages) cultivated in RHIZOtest® devices were, therefore, exposed in a greenhouse for 5, 10 and 15days to various PbO PM doses. The kinetics of transfer and phytotoxicity was assessed in relation to lead concentration and exposure duration. A significant Pb accumulation in leaves (up to 7392mg/kg dry weight (DW) in lettuce) with translocation to roots was observed. Lead foliar exposure resulted in significant phytotoxicity, lipid composition change, a decrease of plant shoot growth (up to 68.2% in lettuce) and net photosynthesis (up to 58% in lettuce). The phytotoxicity results indicated plant adaptation to Pb and a higher sensitivity of lettuce in comparison with cabbage. Air quality needs, therefore, to be considered for the health and quality of vegetables grown in polluted areas, such as certain megacities (in China, Pakistan, Europe, etc.) and furthermore, to assess the health risks associated with their consumption.

  11. Spatial analysis of climate factors used to determine suitability of greenhouse production in Turkey

    NASA Astrophysics Data System (ADS)

    Cemek, Bilal; Güler, Mustafa; Arslan, Hakan

    2015-12-01

    This study aimed to identify the most suitable growing periods for greenhouse production in Turkey in order to make valuable contribution to economic viability. Data collected from the meteorological databases of 81 provinces was used to determine periodic climatological requirements of greenhouses in terms of cooling, heating, natural ventilation, and lighting. Spatial distributions of mean daily outside temperatures and greenhouse heating requirements were derived using ordinary co-kriging (OCK) supported by Geographical Information System (GIS). Mean monthly temperatures throughout the country were found to decrease below 12 °C in January, February, March, and December, indicating heating requirements, whereas temperatures in 94.46 % of the country rose above 22 °C in July, indicating cooling requirements. Artificial lighting is not a requirement in Turkey except for November, December, and January. The Mediterranean, Aegean, Marmara, and Black Sea Regions are more advantageous than the Central, East, and Southeast Anatolia Regions in terms of greenhouse production because the Mediterranean and Aegean Regions are more advantageous in terms of heating, and the Black Sea Region is more advantageous in terms of cooling. Results of our study indicated that greenhouse cultivation of winter vegetables is possible in certain areas in the north of the country. Moreover, greenhouses could alternatively be used for drying fruits and vegetables during the summer period which requires uneconomical cooling systems due to high temperatures in the Mediterranean and Southeastern Anatolian Regions.

  12. Spatial analysis of climate factors used to determine suitability of greenhouse production in Turkey

    NASA Astrophysics Data System (ADS)

    Cemek, Bilal; Güler, Mustafa; Arslan, Hakan

    2017-04-01

    This study aimed to identify the most suitable growing periods for greenhouse production in Turkey in order to make valuable contribution to economic viability. Data collected from the meteorological databases of 81 provinces was used to determine periodic climatological requirements of greenhouses in terms of cooling, heating, natural ventilation, and lighting. Spatial distributions of mean daily outside temperatures and greenhouse heating requirements were derived using ordinary co-kriging (OCK) supported by Geographical Information System (GIS). Mean monthly temperatures throughout the country were found to decrease below 12 °C in January, February, March, and December, indicating heating requirements, whereas temperatures in 94.46 % of the country rose above 22 °C in July, indicating cooling requirements. Artificial lighting is not a requirement in Turkey except for November, December, and January. The Mediterranean, Aegean, Marmara, and Black Sea Regions are more advantageous than the Central, East, and Southeast Anatolia Regions in terms of greenhouse production because the Mediterranean and Aegean Regions are more advantageous in terms of heating, and the Black Sea Region is more advantageous in terms of cooling. Results of our study indicated that greenhouse cultivation of winter vegetables is possible in certain areas in the north of the country. Moreover, greenhouses could alternatively be used for drying fruits and vegetables during the summer period which requires uneconomical cooling systems due to high temperatures in the Mediterranean and Southeastern Anatolian Regions.

  13. Yield performance of cowpea genotypes grown in alkaline soils

    USDA-ARS?s Scientific Manuscript database

    Cowpea or Southernpea [Vigna unguiculata (L.) Walp.] is an important legume crop used as a feed for livestock, as a green vegetable and for consumption of its dry beans which provide 22-25% protein. The crop is very sensitive to alkaline soil conditions. When grown at soil pH of 7.5 or higher, cowp...

  14. Yield performance of cowpea plant introductions grown in calcareous soils

    USDA-ARS?s Scientific Manuscript database

    Cowpea or Southernpea [Vigna unguiculata (L.) Walp.] is an important legume crop used as a feed for livestock, as a green vegetable and for consumption of its dry beans which provide 22-25% protein. The crop is very sensitive to alkaline soil conditions. When grown at a soil pH of 7.5 or higher, co...

  15. Report urges greenhouse action now

    SciTech Connect

    Kerr, R.A.

    1988-07-01

    A recent report that is a product of a process initiated and monitored by three major international organizations, the United Nations Environmental Program, the World Meteorological Organization, and the International Council of Scientific Unions, brings the greenhouse effect into the public eye. The report estimates rates of temperature increase of the earth due to CO/sub 2/ plus the other greenhouse gases. Estimates of the greenhouse effect arising from unrestrained gas emissions and a highly sensitive climate or strong global restraint of emissions and a low climate sensitivity range from 0.8 to 0.06/sup 0/C per decade. Long term policies that the report recommends should be reexamined are increased efficiency in the consumption of energy and a shift toward alternative energy to reduce CO/sub 2/ emissions and reforestation to remove CO/sub 2/ from the atmosphere.

  16. Greenhouse-effect spurs legislation

    SciTech Connect

    Not Available

    1988-12-01

    Senator Timothy E. Wirth (D-Colo.) reintroduced legislation on February 1, 1989, to establish a national energy policy that would slow down the emission of pollutants contributing to the greenhouse effect. Wirth's comprehensive bill to combat the greenhouse effect includes initiatives to: increase energy-efficiency in all sectors of the US economy; expand research and development of nonfossil fuel sources such as solar; encourage technologies to reduce carbon dioxide emission from coal-fired power plants and other sources; direct the World Bank and the International Monetary Fund to develop policies to stop tropical deforestation; and research the greenhouse effect, its causes, and the steps needed to cope with a changing climate.

  17. Can artificial soil be used in the vegetative vigor test for U.S. pesticide registration?

    PubMed

    Bidelspach, Conor; Olszyk, David; Pfleeger, Thomas

    2008-10-01

    Current testing guidelines for pesticide registration for the protection of nontarget plants calls for the use of sterilized, standardized soil consisting of primarily sandy loam, loamy sand, loamy clay, or clay loam that contains up to 3% organic matter. Low organic matter soils can be difficult to manage in a greenhouse setting because when soils dry, they contract, causing impeded water infiltration, or when overwatered, poor drainage increases the chances of anaerobic conditions. The purpose of this study was to determine if the results for the vegetative vigor test differed when using either natural or artificial soils. The herbicide sulfometuron methyl was applied 14 d after emergence at 0.1 and 0.0032 of the suggested field application rate. Six plant species were tested, 4 of the common test species, Zea mays (corn), Glycine max (soybean), Avena sativa (oat), and Lactuca sativa (lettuce), and 2 native plants of the Willamette Valley, Oregon prairie, Bromus carinatus (California brome) and Ranunculus occidentalis (western buttercup). Herbicide application rate was the most significant factor in the experiment regardless of soil type. The different soils generally produced different results, even though the 2 native soils, one from Oregon and the other from Maryland, are both acceptable soils for the pesticide registration tests. The plants grown on artificial soil produced results generally between the Oregon and Maryland soil results. This study indicates that artificial soils may produce results similar to or more sensitive than soils currently used in the vegetative vigor test.

  18. Ecology of Fungus Gnats (Bradysia spp.) in Greenhouse Production Systems Associated with Disease-Interactions and Alternative Management Strategies

    PubMed Central

    Cloyd, Raymond A.

    2015-01-01

    Fungus gnats (Bradysia spp.) are major insect pests of greenhouse-grown horticultural crops mainly due to the direct feeding damage caused by the larvae, and the ability of larvae to transmit certain soil-borne plant pathogens. Currently, insecticides and biological control agents are being used successively to deal with fungus gnat populations in greenhouse production systems. However, these strategies may only be effective as long as greenhouse producers also implement alternative management strategies such as cultural, physical, and sanitation. This includes elimination of algae, and plant and growing medium debris; placing physical barriers onto the growing medium surface; and using materials that repel fungus gnat adults. This article describes the disease-interactions associated with fungus gnats and foliar and soil-borne diseases, and the alternative management strategies that should be considered by greenhouse producers in order to alleviate problems with fungus gnats in greenhouse production systems. PMID:26463188

  19. Ecology of Fungus Gnats (Bradysia spp.) in Greenhouse Production Systems Associated with Disease-Interactions and Alternative Management Strategies.

    PubMed

    Cloyd, Raymond A

    2015-04-09

    Fungus gnats (Bradysia spp.) are major insect pests of greenhouse-grown horticultural crops mainly due to the direct feeding damage caused by the larvae, and the ability of larvae to transmit certain soil-borne plant pathogens. Currently, insecticides and biological control agents are being used successively to deal with fungus gnat populations in greenhouse production systems. However, these strategies may only be effective as long as greenhouse producers also implement alternative management strategies such as cultural, physical, and sanitation. This includes elimination of algae, and plant and growing medium debris; placing physical barriers onto the growing medium surface; and using materials that repel fungus gnat adults. This article describes the disease-interactions associated with fungus gnats and foliar and soil-borne diseases, and the alternative management strategies that should be considered by greenhouse producers in order to alleviate problems with fungus gnats in greenhouse production systems.

  20. Mid-Atlantic Consumer Purchasing Behavior and Knowledge of Locally Grown and Seasonal Produce

    ERIC Educational Resources Information Center

    Chamberlain, Amy J.; Kelley, Kathleen M.; Hyde, Jeffrey

    2013-01-01

    Mid-Atlantic urban consumers were surveyed on their fruit and vegetable purchasing behaviors and their knowledge of produce grown in the region. Consumers were generally unaware of what produce is grown in the mid-Atlantic and during what months they are harvested. Additionally, differences pertaining to number of produce items purchased were…

  1. Mid-Atlantic Consumer Purchasing Behavior and Knowledge of Locally Grown and Seasonal Produce

    ERIC Educational Resources Information Center

    Chamberlain, Amy J.; Kelley, Kathleen M.; Hyde, Jeffrey

    2013-01-01

    Mid-Atlantic urban consumers were surveyed on their fruit and vegetable purchasing behaviors and their knowledge of produce grown in the region. Consumers were generally unaware of what produce is grown in the mid-Atlantic and during what months they are harvested. Additionally, differences pertaining to number of produce items purchased were…

  2. Retractable Roof Greenhouses and Shadehouses

    Treesearch

    Jr. Bartok

    2005-01-01

    Open-roof greenhouses provide a natural environment for plant growth when the outdoor weather is suitable and an artificial environment when it is too hot or cold. Opening the roof over the plants increases light intensity, which can help to control the growth habit, flowering, and crop timing. It also reduces electricity costs because expensive fan cooling is not...

  3. An Introduction to Greenhouse Production.

    ERIC Educational Resources Information Center

    McMahon, Robert W.

    This student manual provides a basic text for those preparing for greenhouse and floriculture work. At the beginning of each chapter, competencies are listed, along with related math and science concepts, and a list of "terms to know"; figures, tables, and photographs may be included. At the end of each chapter, a self-check can be made…

  4. Greenhouse Gas Emissions from Pasture

    USDA-ARS?s Scientific Manuscript database

    Carbon dioxide, nitrous oxide, and methane are the primary greenhouse gases associated with global climate change. Livestock production’s contribution to carbon dioxide emissions is minimal, but it is a substantial contributor to both nitrous oxide and methane emissions. In both grazing and confin...

  5. The Greenhouse Effect: Science and Policy.

    ERIC Educational Resources Information Center

    Schneider, Stephen H.

    1989-01-01

    Discusses many of the scientific questions surrounding the greenhouse effect debate and the issue of plausible responses. Discussion includes topics concerning projecting emissions and greenhouse gas concentrations, estimating global climatic response, economic, social, and political impacts, and policy responses. (RT)

  6. The Greenhouse Effect: Science and Policy.

    ERIC Educational Resources Information Center

    Schneider, Stephen H.

    1989-01-01

    Discusses many of the scientific questions surrounding the greenhouse effect debate and the issue of plausible responses. Discussion includes topics concerning projecting emissions and greenhouse gas concentrations, estimating global climatic response, economic, social, and political impacts, and policy responses. (RT)

  7. Accounting for Greenhouse Gas Emissions from Reservoirs

    EPA Science Inventory

    Nearly three decades of research has demonstrated that the impoundment of rivers and the flooding of terrestrial ecosystems behind dams can increase rates of greenhouse gas emission, particularly methane. The 2006 IPCC Guidelines for National Greenhouse Gas Inventories includes ...

  8. Accounting for Greenhouse Gas Emissions from Reservoirs

    EPA Science Inventory

    Nearly three decades of research has demonstrated that the impoundment of rivers and the flooding of terrestrial ecosystems behind dams can increase rates of greenhouse gas emission, particularly methane. The 2006 IPCC Guidelines for National Greenhouse Gas Inventories includes ...

  9. Building and using the solar greenhouse

    SciTech Connect

    1983-01-01

    Thorough directions are given for planning, constructing and using a solar greenhouse attached to a house. Included is a method of calculating the savings accruing from the use of the greenhouse. (LEW)

  10. The effect on climate change impacts for building products when including the timing of greenhouse gas emissions

    Treesearch

    Richard D Bergman

    2012-01-01

    Greenhouse gases (GHGs) trap infrared radiation emitting from the Earth’s surface to generate the “greenhouse effect” thus keeping the planet warm. Many natural activities including rotting vegetation emit GHGs such as carbon dioxide to produce this natural affect. However, in the last 200 years or so, human activity has increased the atmospheric concentrations of GHGs...

  11. Engineering concepts for inflatable Mars surface greenhouses.

    PubMed

    Hublitz, I; Henninger, D L; Drake, B G; Eckart, P

    2004-01-01

    A major challenge of designing a bioregenerative life support system for Mars is the reduction of the mass, volume, power, thermal and crew-time requirements. Structural mass of the greenhouse could be saved by operating the greenhouse at low atmospheric pressure. This paper investigates the feasibility of this concept. The method of equivalent system mass is used to compare greenhouses operated at high atmospheric pressure to greenhouses operated at low pressure for three different lighting methods: natural, artificial and hybrid lighting.

  12. Handling Procedures of Vegetable Crops

    NASA Technical Reports Server (NTRS)

    Perchonok, Michele; French, Stephen J.

    2004-01-01

    The National Aeronautics and Space Administration (NASA) is working towards future long duration manned space flights beyond low earth orbit. The duration of these missions may be as long as 2.5 years and will likely include a stay on a lunar or planetary surface. The primary goal of the Advanced Food System in these long duration exploratory missions is to provide the crew with a palatable, nutritious, and safe food system while minimizing volume, mass, and waste. Vegetable crops can provide the crew with added nutrition and variety. These crops do not require any cooking or food processing prior to consumption. The vegetable crops, unlike prepackaged foods, will provide bright colors, textures (crispy), and fresh aromas. Ten vegetable crops have been identified for possible use in long duration missions. They are lettuce, spinach, carrot, tomato, green onion, radish, bell pepper, strawberries, fresh herbs, and cabbage. Whether these crops are grown on a transit vehicle (e.g., International Space Station) or on the lunar or planetary surface, it will be necessary to determine how to safely handle the vegetables while maintaining acceptability. Since hydrogen peroxide degrades into water and oxygen and is generally recognized as safe (GRAS), hydrogen peroxide has been recommended as the sanitizer. The objective of th is research is to determine the required effective concentration of hydrogen peroxide. In addition, it will be determined whether the use of hydrogen peroxide, although a viable sanitizer, adversely affects the quality of the vegetables. Vegetables will be dipped in 1 % hydrogen peroxide, 3% hydrogen peroxide, or 5% hydrogen peroxide. Treated produce and controls will be stored in plastic bags at 5 C for up to 14 days. Sensory, color, texture, and total plate count will be measured. The effect on several vegetables including lettuce, radish, tomato and strawberries has been completed. Although each vegetable reacts to hydrogen peroxide differently, the

  13. Graphic Grown Up

    ERIC Educational Resources Information Center

    Kim, Ann

    2009-01-01

    It's no secret that children and YAs are clued in to graphic novels (GNs) and that comics-loving adults are positively giddy that this format is getting the recognition it deserves. Still, there is a whole swath of library card-carrying grown-up readers out there with no idea where to start. Splashy movies such as "300" and "Spider-Man" and their…

  14. Graphic Grown Up

    ERIC Educational Resources Information Center

    Kim, Ann

    2009-01-01

    It's no secret that children and YAs are clued in to graphic novels (GNs) and that comics-loving adults are positively giddy that this format is getting the recognition it deserves. Still, there is a whole swath of library card-carrying grown-up readers out there with no idea where to start. Splashy movies such as "300" and "Spider-Man" and their…

  15. The Greenhouse Effect and Built Environment Education.

    ERIC Educational Resources Information Center

    Greenall Gough, Annette; Gough, Noel

    The greenhouse effect has always existed. Without the greenhouse effect, Earth could well have the oven-like environment of Venus or the deep-freeze environment of Mars. There is some debate about how much the Earth's surface temperature will rise given a certain amount of increase in the amount of greenhouse gases such as carbon dioxide, nitrous…

  16. Using waste oil to heat a greenhouse

    Treesearch

    Marla Schwartz

    2009-01-01

    During the winter of 1990, Northwoods Nursery (Elk River, ID) purchased a wood-burning system to heat the current greenhouses. This system burned slabs of wood to heat water that was then pumped into the greenhouses. The winter of 1990 was extremely harsh, requiring non-stop operation of the heating system. In order to keep seedlings in the greenhouse from freezing,...

  17. Phytotoxicity of zinc and manganese to seedlings grown in soil contaminated by zinc smelting

    USDA-ARS?s Scientific Manuscript database

    Historic emissions from two zinc smelters have damaged the forest on Blue Mountain near Palmerton, Pennsylvania, USA. Seedlings of soybeans and five tree species were grown in a greenhouse in a series of mixtures of smelter-contaminated and reference soils. As little as 10% Palmerton soil mixed wi...

  18. Ectomycorrhizal Colonization of Container-Grown Northern Red Oak as Affected by Fertility

    Treesearch

    John L. Ruehle

    1980-01-01

    Abstract - The effects of different fertility regimes on Pisolithus tinctorius ectomycorrhizal development on northern red oak grown in containers was tested in the greenhouse. Artificial infestation of a milled pine bark-sewage sludge growing medium produced the best ectomycorrhizal development (63 percent) when a nutrient solution with 100pg/ml N...

  19. Perfluoroalkyl acid distribution in various plant compartments of edible crops grown in biosolids-amended soils

    EPA Science Inventory

    Crop uptake of perfluoroalkyl acids (PFAAs) from biosolids-amended soil has been identified as a potential pathway for PFAA entry into the terrestrial food chain. This study compared the uptake of PFAAs in greenhouse-grown radish (Raphanus sativus), celery (Apium graveolens var.d...

  20. Perfluoroalkyl acid distribution in various plant compartments of edible crops grown in biosolids-amended soils

    EPA Science Inventory

    Crop uptake of perfluoroalkyl acids (PFAAs) from biosolids-amended soil has been identified as a potential pathway for PFAA entry into the terrestrial food chain. This study compared the uptake of PFAAs in greenhouse-grown radish (Raphanus sativus), celery (Apium graveolens var.d...

  1. Towner State Nursery weed control program for field-grown conifer nursery stock

    Treesearch

    Roy LaFramboise

    2002-01-01

    The Towner State Nursery is owned and operated by the North Dakota Forest Service. The nursery is 160 acres in size and is located in north-central North Dakota. The Towner Nursery specializes in the production of conifer seedlings, transplants, and greenhouse-grown container stock for conservation tree plantings. Transplants constitute 80% of the stock produced. The...

  2. A Guide to Energy Savings - For the Vegetable Producer.

    ERIC Educational Resources Information Center

    Wynn, N. A.

    This booklet gives a brief overview of energy use patterns in vegetable production and gives examples of cutting the cost of energy in fertilization, weed management, insect pest management, irrigation, harvesting, use of equipment, and greenhouses. Finally, energy use recordkeeping is discussed. (BB)

  3. Probabilistic viability calculations for cryopreserving vegetatively propagated collections in genebanks

    USDA-ARS?s Scientific Manuscript database

    Vegetatively propagated plant collections within genebanks are vulnerable to threats when they are maintained in field or greenhouse conditions. International genebanking standards recommend that these collections be securely backed-up at either secondary locations or by using in vitro culture or cr...

  4. Evaluation of cadmium in greenhouse soils and agricultural products of Jiroft (Iran) using microwave digestion prior to atomic absorption spectrometry determination.

    PubMed

    Afzali, Daryoush; Fathirad, Fariba; Afzali, Zahra; Majdzadeh-Kermani, Seyed Mohammad Javad

    2015-03-01

    This study determines total levels of potentially toxic trace element, Cd (II) in Jiroft (Kerman, Iran) greenhouse soil and agricultural products that are grown in these greenhouses (tomatoes and cucumbers), and the comparison with soil outside of greenhouse using microwave digestion prior to flame atomic absorption spectrometry determination. The results show that the cadmium concentration in greenhouse soil is 0.9-1.9 mg kg(-1) and out of greenhouse is 0.4-1.0 mg kg(-1). Also, cadmium concentration range in tomatoes and cucumbers is about 0.07-0.40 mg kg(-1). The obtained results show that the concentration of this metal in greenhouse soil is higher than outside soil samples and is below the safe limit.

  5. Mineral composition of organically grown tomato

    NASA Astrophysics Data System (ADS)

    Ghambashidze, Giorgi

    2014-05-01

    In recent years, consumer concerns on environmental and health issues related to food products have increased and, as a result, the demand for organically grown production has grown. Results indicate that consumers concerned about healthy diet and environmental degradation are the most likely to buy organic food, and are willing to pay a high premium. Therefore, it is important to ensure the quality of the produce, especially for highly consumed products. The tomato (Lycopersicon esculentum) is one of the most widely consumed fresh vegetables in the world. It is also widely used by the food industries as a raw material for the production of derived products such as purees or ketchup. Consequently, many investigations have addressed the impact of plant nutrition on the quality of tomato fruit. The concentrations of minerals (P, Na, K, Ca and Mg) and trace elements (Cu, Zn and Mn) were determined in tomatoes grown organically in East Georgia, Marneuli District. The contents of minerals and Mn seem to be in the range as shown in literature. Cu and Zn were found in considerably high amounts in comparison to maximum permissible values established in Georgia. Some correlations were observed between the minerals and trace elements studied. K and Mg were strongly correlated with Cu and Zn. Statistically significant difference have shown also P, K and Mg based between period of sampling.

  6. [Effects of arbuscular mycorrhizal fungi on the vegetation restoration of different types of coal mine spoil banks].

    PubMed

    Zhao, Ren-Xin; Guo, Wei; Fu, Rui-Ying; Zhao, Wen-Jing; Guo, Jiang-Yuan; Bi, Na; Zhang, Jun

    2013-11-01

    A greenhouse pot experiment was conducted to investigate the influence of arbuscular mycorrhizal (AM) fungi Glomus etunicatum (GE) and Glomus versiforme (GV) on the plant growth, nutrient uptake, C: N: P stoichiometric, uptake of heavy metals by maize (Zea mays L.) grown in three types of coal mine spoil banks. The aim was to provide a technical basis for the revegetation of coal mine spoil banks in grassland ecosystem. The results indicated that the symbiotic associations were successfully established between two isolates and maize grown in the three substrates, with an average mycorrhizal colonization rate ranging from 36% to 54%. The colonization of two AM fungi significantly increased the dry weight of maize grown in recent discharged and weathered coal mine spoils and GE increased those grown in weathered coal mine spoil. Inoculation with AM fungi promoted the uptake of N, P and K by maize to varying degrees. In addition, inoculation with GE and GV also decreased C: N: P ratios, supporting the growth rate hypothesis, and had significantly differences on concentrations of Cu, Fe, Mn and Zn in shoots and roots of maize. The results indicated that GE and GV had different mycorrhizal effects on maize in the three types of substrates. GV was more suitable for the revegetation of recent discharged coal mine spoil and weathered coal mine spoil, while GE was more suitable for the revegetation of spontaneous combusted coal mine spoil. The experiment demonstrates that AM fungi have a potential role for maize to enhance the ability to adapt the composite adversity of different types of coal mine spoil and play a positive role in the revegetation of different coal mine spoil banks. Further field experiments should be conducted to evaluate the practical effects of AM fungi on the vegetation restoration of different types of coal mine spoil under field conditions.

  7. Accumulation of lead and arsenic in Malabar spinach (Basella alba L.) and sweet potato (Ipomoea batatas L.) leaves grown on urban and orchard soils.

    USDA-ARS?s Scientific Manuscript database

    Migration of people of different ethnic backgrounds to U.S. urban areas has resulted in different ethnic vegetable crops being grown in urban gardens. There are concerns that some ethnic vegetable crops may accumulate heavy metals when grown on urban soils. The objective of this study was to evalua...

  8. Volcanoes can muddle the greenhouse

    SciTech Connect

    Kerr, R.A.

    1990-01-01

    As scientists and politicians anxiously eye signs of global greenhouse warming, climatologists are finding the best evidence yet that a massive volcanic eruption can temporarily bring the temperature down a notch or two. Such a cooling could be enough to set the current global warming back more than a decade, confusing any efforts to link it to the greenhouse effect. By effectively eliminating some nonvolcanic climate changes from the record of the past 100 years, researchers have detected drops in global temperature of several tenths of a degree within 1 to 2 years of volcanic eruptions. Apparently, the debris spewed into the stratosphere blocked sunlight and caused the temperature drops. For all their potential social significance, the climate effects of volcanoes have been hard to detect. The problem has been in identifying a volcanic cooling among the nearly continuous climate warmings and coolings of a similar size that fill the record. The paper reviews how this was done.

  9. Greenhouse Gas Reductions: SF6

    ScienceCinema

    Anderson, Diana

    2016-07-12

    Argonne National Laboratory is leading the way in greenhouse gas reductions, particularly with the recapture and recycling of sulfur hexafluoride (SF6). SF6 is a gas used in industry as an anti-arcing agent. It is an extremely potent greenhouse gas — one pound of SF6 is equivalent to 12 tons of carbon dioxide. While the U.S. does not currently regulate SF6 emissions, Argonne is proactively and voluntarily recovering and recycling to reduce SF6 emissions. Argonne saves over 16,000 tons of SF6 from being emitted into the atmosphere each year, and by recycling the gas rather than purchasing it new, we save taxpayers over $208,000 each year.

  10. The making of greenhouse policy

    SciTech Connect

    Bromley, D.A.

    1990-01-01

    The problem of anthropogenic climate change on a global scale has raised a public policy debate which has become the archetypical science policy issue. Against a background of natural changes in the earth's climate man has altered the surface of the earth and its atmosphere. We have evidence of increases in greenhouse gases in the atmosphere. The computer models of the climate effect take into account this input, but do not adequately simulate fundamental aspects of the Earth system which may reduce or increase the predicted climate effects. The average global temperatures did not increase from 1979 to 1989 yet global increases in releases of greenhouse gases to the atmosphere were at unprecendented levels. The Intergovernmental Panel on Climate Change, an international body, has set up three working groups to investigate different aspects of climate change. Their reports were presented to the Second World Climate Conference in Geneva from October 29 to November 7, 1990. All three groups cited uncertainties in their assessments of effects of global climate change. A government wide U.S. Global Change Research Program has been formed to monitor and understand the Earth system and predict global change. President Bush has asked for over $1 billion to fund this research program. Social and economic factors will play a large role in any policy decisions that affect climate change. Policies have been instituted by this administration which will reduce greenhouse-gas-emissions. These include the phasing out of CFCs by the year 2000, The Clean Air Act being debated by Congress, and a National Energy Strategy. President Bush has proposed the U.S. host the first negotiating sessions leading to an international agreement on greenhouse policy.

  11. Greenhouse-gas payback times for crop-based biofuels

    NASA Astrophysics Data System (ADS)

    Elshout, P. M. F.; van Zelm, R.; Balkovic, J.; Obersteiner, M.; Schmid, E.; Skalsky, R.; van der Velde, M.; Huijbregts, M. A. J.

    2015-06-01

    A global increase in the demand for crop-based biofuels may be met by cropland expansion, and could require the sacrifice of natural vegetation. Such land transformation alters the carbon and nitrogen cycles of the original system, and causes significant greenhouse-gas emissions, which should be considered when assessing the global warming performance of crop-based biofuels. As an indicator of this performance we propose the use of greenhouse-gas payback time (GPBT), that is, the number of years it takes before the greenhouse-gas savings due to displacing fossil fuels with biofuels equal the initial losses of carbon and nitrogen stocks from the original ecosystem. Spatially explicit global GPBTs were derived for biofuel production systems using five different feedstocks (corn, rapeseed, soybean, sugarcane and winter wheat), cultivated under no-input and high-input farm management. Overall, GPBTs were found to range between 1 and 162 years (95% range, median: 19 years) with the longest GPBTs occurring in the tropics. Replacing no-input with high-input farming typically shortened the GPBTs by 45 to 79%. Location of crop cultivation was identified as the primary factor driving variation in GPBTs. This study underscores the importance of using spatially explicit impact assessments to guide biofuel policy.

  12. Estimating greenhouse gas emissions from future Amazonian hydroelectric reservoirs

    NASA Astrophysics Data System (ADS)

    de Faria, Felipe A. M.; Jaramillo, Paulina; Sawakuchi, Henrique O.; Richey, Jeffrey E.; Barros, Nathan

    2015-12-01

    Brazil plans to meet the majority of its growing electricity demand with new hydropower plants located in the Amazon basin. However, large hydropower plants located in tropical forested regions may lead to significant carbon dioxide and methane emission. Currently, no predictive models exist to estimate the greenhouse gas emissions before the reservoir is built. This paper presents two different approaches to investigate the future carbon balance of eighteen new reservoirs in the Amazon. The first approach is based on a degradation model of flooded carbon stock, while the second approach is based on flux data measured in Amazonian rivers and reservoirs. The models rely on a Monte Carlo simulation framework to represent the balance of the greenhouse gases into the atmosphere that results when land and river are converted into a reservoir. Further, we investigate the role of the residence time/stratification in the carbon emissions estimate. Our results imply that two factors contribute to reducing overall emissions from these reservoirs: high energy densities reservoirs, i.e., the ratio between the installed capacity and flooded area, and vegetation clearing. While the models’ uncertainties are high, we show that a robust treatment of uncertainty can effectively indicate whether a reservoir in the Amazon will result in larger greenhouse gas emissions when compared to other electricity sources.

  13. Preliminary greenhouse design for a Martian colony: Structural, solar collection, and light distribution systems

    NASA Astrophysics Data System (ADS)

    1990-11-01

    The design of a greenhouse that will be a component of a long-term habitat on Mars is presented. The greenhouse will be the primary food source for people stationed on Mars. The food will be grown in three identical underground modules, pressurized at 1 atm to allow a shirt-sleeve environment within the greenhouse. The underground location will support the structure, moderate the large environmental variations on the surface, and protect the crops from cosmic radiation. The design effort is concentrated on the outer structure and the lighting system for the greenhouse. The structure is inflatable and made of a Kevlar 49/Epoxy composite and a pipe-arched system that is corrugated to increase stiffness. This composite is pliable in an uncured state, which allows it to be efficiently packaged for transport. The lighting system consists of several flat-plate fiber optic solar collectors with dual-axis tracking systems that will continually track the sun. This design is modeled after the Himawari collector, which was designed by Dr. Kei Mori and is currently in use in Japan. The light will pass through Fresnel lenses that filter out undesirable wavelengths and send the light into the greenhouses by way of fiber optic cables. When the light arrives at the greenhouse, it is dispersed to the plants via a waveguide and diffuser system.

  14. Preliminary greenhouse design for a Martian colony: Structural, solar collection, and light distribution systems

    NASA Technical Reports Server (NTRS)

    1990-01-01

    The design of a greenhouse that will be a component of a long-term habitat on Mars is presented. The greenhouse will be the primary food source for people stationed on Mars. The food will be grown in three identical underground modules, pressurized at 1 atm to allow a shirt-sleeve environment within the greenhouse. The underground location will support the structure, moderate the large environmental variations on the surface, and protect the crops from cosmic radiation. The design effort is concentrated on the outer structure and the lighting system for the greenhouse. The structure is inflatable and made of a Kevlar 49/Epoxy composite and a pipe-arched system that is corrugated to increase stiffness. This composite is pliable in an uncured state, which allows it to be efficiently packaged for transport. The lighting system consists of several flat-plate fiber optic solar collectors with dual-axis tracking systems that will continually track the sun. This design is modeled after the Himawari collector, which was designed by Dr. Kei Mori and is currently in use in Japan. The light will pass through Fresnel lenses that filter out undesirable wavelengths and send the light into the greenhouses by way of fiber optic cables. When the light arrives at the greenhouse, it is dispersed to the plants via a waveguide and diffuser system.

  15. Greenhouse gas emissions from constructed wetlands treating dairy wastewater

    NASA Astrophysics Data System (ADS)

    Glass, Vimy M.

    In Nova Scotia, constructed wetland systems are widely considered as effective treatment systems for agricultural wastewater. Although research has examined the water quality treatment attributes, there has been limited focus on the air quality effects of these systems. Six operational pilot-scale constructed wetlands were built with flow-through chambers for quantifying greenhouse gas (GHG) emissions in Truro, NS. Utilized within this facility were three gas analyzers to monitor GHG emissions (CO2, N 2O, CH4) and the gaseous fluxes could then be determined using the mass balance micrometeorological technique. Prior to data collection, the site underwent testing to ensure valid conclusions and replicated responses from the wetland systems. Those wetlands receiving wastewater at a typical HLR (10.6 mm d-1) and with ample vegetation displayed the best concentration reductions. During the growing season (GS), average CO 2 consumption was large (approximately -44 g CO2m -2 d-1) for wetlands with dense vegetation (approximately 100% cover) at the typical loading rate. For those wetlands at higher loading rates, CO2 emissions were observed to be as high as +9.2 g CO 2m-2 d-1. Wetlands with typical loading rates and healthy aquatic vegetation produced average CH4 fluxes of approximately 43 g CO2 eq. m-2d-1, while higher loaded systems with little vegetation approached 90 g CO 2 eq. m-2d-1. During the non-growing season (NGS), all vegetated wetlands exhibited higher CH4 emissions than the non-vegetated systems (˜15 to 20% higher). Vegetation maturity played a strong role in the GHG balance. The average CO2consumption for wetlands with established vegetation was ˜ -36 g CO2 m -2 d-1 during the GS. Wetland 4, which had been newly transplanted in 2004, had the highest single day CO2 consumption of -152 g CO2m-2 d-1 . Methane emissions from wetlands with two-year-old vegetation followed the same pattern but were approximately half of the emissions recorded from 2003. The

  16. Developmental, nutritional and hormonal anomalies of weightlessness-grown wheat.

    PubMed

    Carman, J G; Hole, P; Salisbury, F B; Bingham, G E

    2015-07-01

    The behavior of water in weightlessness, as occurs in orbiting spacecraft, presents multiple challenges for plant growth. Soils remain saturated, impeding aeration, and leaf surfaces remain wet, impeding gas exchange. Herein we report developmental and biochemical anomalies of "Super Dwarf" wheat (Triticum aestivum L.) grown aboard Space Station Mir during the 1996-97 "Greenhouse 2" experiment. Leaves of Mir-grown wheat were hyperhydric, senesced precociously and accumulated aromatic and branched-chain amino acids typical of tissues experiencing oxidative stress. The highest levels of stress-specific amino acids occurred in precociously-senescing leaves. Our results suggest that the leaf ventilation system of the Svet Greenhouse failed to remove sufficient boundary layer water, thus leading to poor gas exchange and onset of oxidative stress. As oxidative stress in plants has been observed in recent space-flight experiments, we recommend that percentage water content in apoplast free-spaces of leaves be used to evaluate leaf ventilation effectiveness. Mir-grown plants also tillered excessively. Crowns and culms of these plants contained low levels of abscisic acid but high levels of cytokinins. High ethylene levels may have suppressed abscisic acid synthesis, thus permitting cytokinins to accumulate and tillering to occur. Copyright © 2015 The Committee on Space Research (COSPAR). Published by Elsevier Ltd. All rights reserved.

  17. Developmental, nutritional and hormonal anomalies of weightlessness-grown wheat

    NASA Astrophysics Data System (ADS)

    Carman, J. G.; Hole, P.; Salisbury, F. B.; Bingham, G. E.

    2015-07-01

    The behavior of water in weightlessness, as occurs in orbiting spacecraft, presents multiple challenges for plant growth. Soils remain saturated, impeding aeration, and leaf surfaces remain wet, impeding gas exchange. Herein we report developmental and biochemical anomalies of "Super Dwarf" wheat (Triticum aestivum L.) grown aboard Space Station Mir during the 1996-97 "Greenhouse 2" experiment. Leaves of Mir-grown wheat were hyperhydric, senesced precociously and accumulated aromatic and branched-chain amino acids typical of tissues experiencing oxidative stress. The highest levels of stress-specific amino acids occurred in precociously-senescing leaves. Our results suggest that the leaf ventilation system of the Svet Greenhouse failed to remove sufficient boundary layer water, thus leading to poor gas exchange and onset of oxidative stress. As oxidative stress in plants has been observed in recent space-flight experiments, we recommend that percentage water content in apoplast free-spaces of leaves be used to evaluate leaf ventilation effectiveness. Mir-grown plants also tillered excessively. Crowns and culms of these plants contained low levels of abscisic acid but high levels of cytokinins. High ethylene levels may have suppressed abscisic acid synthesis, thus permitting cytokinins to accumulate and tillering to occur.

  18. Greenhouse Gases Monitoring from Space

    NASA Astrophysics Data System (ADS)

    Moriyama, Takashi

    The role of greenhouse gases in global warming processes and an important element of the global carbon cycle is widely recognized. With the advent of the technical means to provide new monitoring and measurement of greenhouse gases (GHG) from space, JAXA has identified the coordination of these measurements and their application by cooperating with international space agencies. In order to foster the use of space-based GHG observations and consolidate data requirements for the next generation GHG monitoring mission from space, a synergetic strategy for easy access to GHG satellite observations, including GOSAT (Greenhouse Gases Monitoring Satellite, JAXA) and current observations should be developed, and also harmonizing the next generation of GHG satellite observations shoud be facilitated. The Paper describes the current status of international activities of GHG monitoring from space and relations with policy makers and stake holders. The long term GHG monitoring from space is also proposed by respecting the GEO Carbon Strategy which is published in March 2010. Also, GOSAT sample XCO2 and XCH4 global column amount datasets will be introduced with the avtivities of validation campaign.

  19. Greenhouse Gas Emissions from Brazilian Sugarcane Soils

    NASA Astrophysics Data System (ADS)

    Carmo, J.; Pitombo, L.; Cantarella, H.; Rosseto, R.; Andrade, C.; Martinelli, L.; Gava, G.; Vargas, V.; Sousa-Neto, E.; Zotelli, L.; Filoso, S.; Neto, A. E.

    2012-04-01

    Bioethanol from sugarcane is increasingly seen as a sustainable alternative energy source. Besides having high photosynthetic efficiency, sugarcane is a perennial tropical grass crop that can re-grow up to five or more years after being planted. Brazil is the largest producer of sugarcane in the world and management practices commonly used in the country lead to lower rates of inorganic N fertilizer application than sugarcane grown elsewhere, or in comparison to other feedstocks such as corn. Therefore, Brazilian sugarcane ethanol potentially promotes greenhouse gas savings. For that reason, several recent studies have attempted to assess emissions of greenhouse gases (GHG) during sugarcane production in the tropics. However, estimates have been mainly based on models due to a general lack of field data. In this study, we present data from in situ experiments on emission of three GHG (CO2, N2O, and CH4) in sugarcane fields in Brazil. Emissions are provided for sugarcane in different phases of the crop life cycle and under different management practices. Our results show that the use of nitrogen fertilizer in sugarcane crops resulted in an emission factor for N2O similar to those predicted by IPCC (1%), ranging from 0.59% in ratoon cane to 1.11% in plant cane. However, when vinasse was applied in addition to mineralN fertilizer, emissions of GHG increased in comparison to those from the use of mineral N fertilizer alone. Emissions increased significantly when experiments mimicked the accumulation of cane trash on the soil surface with 14 tons ha-1and 21 tons ha-1, which emission factor were 1.89% and 3.03%, respectively. This study is representative of Brazilian sugarcane systems under specific conditions for key factors affecting GHG emissions from soils. Nevertheless, the data provided will improve estimates of GHG from Brazilian sugarcane, and efforts to assess sugarcane ethanol sustainability and energy balance. Funding provided by the São Paulo Research

  20. Inoculations with Arbuscular Mycorrhizal Fungi Increase Vegetable Yields and Decrease Phoxim Concentrations in Carrot and Green Onion and Their Soils

    PubMed Central

    Wang, Fa Yuan; Tong, Rui Jian; Shi, Zhao Yong; Xu, Xiao Feng; He, Xin Hua

    2011-01-01

    Background As one of the most widely used organophosphate insecticides in vegetable production, phoxim (C12H15N2O3PS) is often found as residues in crops and soils and thus poses a potential threat to public health and environment. Arbuscular mycorrhizal (AM) fungi may make a contribution to the decrease of organophosphate residues in crops and/or the degradation in soils, but such effects remain unknown. Methodology/Principal Findings A greenhouse pot experiment studied the influence of AM fungi and phoxim application on the growth of carrot and green onion, and phoxim concentrations in the two vegetables and their soil media. Treatments included three AM fungal inoculations with Glomus intraradices BEG 141, G. mosseae BEG 167, and a nonmycorrhizal control, and four phoxim application rates (0, 200, 400, 800 mg l−1, while 400 mg l−1 rate is the recommended dose in the vegetable production system). Carrot and green onion were grown in a greenhouse for 130 d and 150 d. Phoxim solution (100 ml) was poured into each pot around the roots 14d before plant harvest. Results showed that mycorrhizal colonization was higher than 70%, and phoxim application inhibited AM colonization on carrot but not on green onion. Compared with the nonmycorrhizal controls, both shoot and root fresh weights of these two vegetables were significantly increased by AM inoculations irrespective of phoxim application rates. Phoxim concentrations in shoots, roots and soils were increased with the increase of phoxim application rate, but significantly decreased by the AM inoculations. Soil phosphatase activity was enhanced by both AM inocula, but not affected by phoxim application rate. In general, G. intraradices BEG 141 had more pronounced effects than G. mosseae BEG 167 on the increase of fresh weight production in both carrot and green onion, and the decrease of phoxim concentrations in plants and soils. Conclusions/Significance Our results indicate a promising potential of AM fungi for

  1. Mitigating cadmium accumulation in greenhouse lettuce production using biochar.

    PubMed

    Zheng, Ruilun; Sun, Guoxin; Li, Cui; Reid, Brian J; Xie, Zubin; Zhang, Bo; Wang, Qinghai

    2017-03-01

    Greenhouse experiments were conducted to investigate the influence of rice straw biochar (RSB) on soil cadmium (Cd) availability and accumulation in lettuce. The RSB was applied either in bands or broadcast in the test site of four greenhouses with soil Cd concentrations ranging from 1.70-3.14 μg g(-1). Biochar doses applied in bands were half of those broadcast. The Cd levels in the shoots of lettuce were observed to be reduced by up to 57% with increasing RSB application rate (0, 6, 12, 18 t ha(-1)). Following RSB application, shoot Cd concentrations of lettuce were reduced to below the Chinese threshold value set for food, and hazard quotients for Cd associated with vegetable consumption were reduced from 0.70-1.11 to 0.42-0.65. A decrease in soil bulk density (11%) and increases in water holding capacity (16%), available phosphorus (30%), available potassium (197%), and lettuce yield (15%) were observed after RSB application. Multiple linear regression analysis suggested that the soil extractable Cd level (but not biomass dilution) and soil bulk density, as influenced by RSB addition, were the dominant contributors to the shoot Cd levels in lettuce and lettuce yield, respectively. These results highlight the potential for RSB to mitigate the phytoaccumulation of Cd and thereby to reduce human exposure from vegetable consumption. Application of biochar in band, rather than broadcasting over the entire area, represents an opportunity to halve the biochar cost while retaining a good remediation effect.

  2. Seedborne fungal contamination: consequences in space-grown wheat

    NASA Technical Reports Server (NTRS)

    Bishop, D. L.; Levine, H. G.; Kropp, B. R.; Anderson, A. J.; Hood, E. E. (Principal Investigator)

    1997-01-01

    Plants grown in microgravity are subject to many environmental stresses that may promote microbial growth and result in disease symptoms. Wheat (cv. Super Dwarf) recovered from an 8-day mission aboard a NASA (National Aeronautics and Space Administration) space shuttle showed disease symptoms, including girdling of leaf sheaths and chlorosis and necrosis of leaf and root tissues. A Neotyphodium species was isolated from the seed and leaf sheaths of symptomatic wheat used in the spaceflight mission. Certain isozymes of a peroxidase unique to extracts from the microgravity-grown plants were observed in extracts from earth-grown Neotyphodium-infected plants but were not present in noninfected wheat. The endophytic fungus was eliminated from the wheat seed by prolonged heat treatment at 50 degrees C followed by washes with water at 50 degrees C. Plants from wheat seed infected with the Neotyphodium endophyte were symptomless when grown under greenhouse conditions, whereas symptoms appeared after only 4 days of growth in closed containers. Disease spread from an infected plant to noninfected plants in closed containers. Dispersion via spores was found on asymptomatic plants at distances of 7 to 18 cm from infected plants. The size and shape of the conidia, mycelia, and phialide-bearing structures and the ability to grow rapidly on carbohydrates, especially xylose, resembled the characteristics of N. chilense, which is pathogenic on orchard grass, Doctylis glomerati. The Neotyphodium wheat isolate caused disease symptoms on other cereals (wheat cv. Malcolm, orchard grass, barley, and maize) grown in closed containers.

  3. Seedborne fungal contamination: consequences in space-grown wheat.

    PubMed

    Bishop, D L; Levine, H G; Kropp, B R; Anderson, A J

    1997-11-01

    Plants grown in microgravity are subject to many environmental stresses that may promote microbial growth and result in disease symptoms. Wheat (cv. Super Dwarf) recovered from an 8-day mission aboard a NASA (National Aeronautics and Space Administration) space shuttle showed disease symptoms, including girdling of leaf sheaths and chlorosis and necrosis of leaf and root tissues. A Neotyphodium species was isolated from the seed and leaf sheaths of symptomatic wheat used in the spaceflight mission. Certain isozymes of a peroxidase unique to extracts from the microgravity-grown plants were observed in extracts from earth-grown Neotyphodium-infected plants but were not present in noninfected wheat. The endophytic fungus was eliminated from the wheat seed by prolonged heat treatment at 50 degrees C followed by washes with water at 50 degrees C. Plants from wheat seed infected with the Neotyphodium endophyte were symptomless when grown under greenhouse conditions, whereas symptoms appeared after only 4 days of growth in closed containers. Disease spread from an infected plant to noninfected plants in closed containers. Dispersion via spores was found on asymptomatic plants at distances of 7 to 18 cm from infected plants. The size and shape of the conidia, mycelia, and phialide-bearing structures and the ability to grow rapidly on carbohydrates, especially xylose, resembled the characteristics of N. chilense, which is pathogenic on orchard grass, Doctylis glomerati. The Neotyphodium wheat isolate caused disease symptoms on other cereals (wheat cv. Malcolm, orchard grass, barley, and maize) grown in closed containers.

  4. Seedborne fungal contamination: consequences in space-grown wheat

    NASA Technical Reports Server (NTRS)

    Bishop, D. L.; Levine, H. G.; Kropp, B. R.; Anderson, A. J.; Hood, E. E. (Principal Investigator)

    1997-01-01

    Plants grown in microgravity are subject to many environmental stresses that may promote microbial growth and result in disease symptoms. Wheat (cv. Super Dwarf) recovered from an 8-day mission aboard a NASA (National Aeronautics and Space Administration) space shuttle showed disease symptoms, including girdling of leaf sheaths and chlorosis and necrosis of leaf and root tissues. A Neotyphodium species was isolated from the seed and leaf sheaths of symptomatic wheat used in the spaceflight mission. Certain isozymes of a peroxidase unique to extracts from the microgravity-grown plants were observed in extracts from earth-grown Neotyphodium-infected plants but were not present in noninfected wheat. The endophytic fungus was eliminated from the wheat seed by prolonged heat treatment at 50 degrees C followed by washes with water at 50 degrees C. Plants from wheat seed infected with the Neotyphodium endophyte were symptomless when grown under greenhouse conditions, whereas symptoms appeared after only 4 days of growth in closed containers. Disease spread from an infected plant to noninfected plants in closed containers. Dispersion via spores was found on asymptomatic plants at distances of 7 to 18 cm from infected plants. The size and shape of the conidia, mycelia, and phialide-bearing structures and the ability to grow rapidly on carbohydrates, especially xylose, resembled the characteristics of N. chilense, which is pathogenic on orchard grass, Doctylis glomerati. The Neotyphodium wheat isolate caused disease symptoms on other cereals (wheat cv. Malcolm, orchard grass, barley, and maize) grown in closed containers.

  5. Experimental Investigations on Uprooting of Riparian Vegetation

    NASA Astrophysics Data System (ADS)

    Francalanci, S.; Calvani, G.; Solari, L.; Gumiero, B.

    2016-12-01

    The morphology of a river reach is the result of many processes involving the motion of sediment (erosion, transport and deposition), the hydrological regime and the development and growth of vegetation. River evolution in the presence of vegetation depends on establishment of pioneer riparian seedlings on bars, and consequently on either their survival or death (Bertoldi et al, 2014). Flooding events can cause young vegetation mortality by burying it with sediment or by uprooting. Despite its important implications in river morphodynamics, interaction of vegetation with sediment transport and its decay due to high flow events have been poorly investigated in the past (Edmaier et al., 2011). In this work, we focused on vegetation uprooting by flow. Aims of the research are to define shear stress threshold and discharge/time relation for flow induced uprooting of juvenile seedlings. We considered two different types of vegetation: Avena Sativa, grown from seeds in external boxes, was used to reproduce annual grass, and Salix Purpurea, collected in the field, a more resistant shrub that can be commonly found in gravel bars. The experiments were carried out in a 5 m long flume in the Hydraulic Laboratory in Florence. The first part of the flume consisted of rigid bed, then a mobile vegetated bed was build for a length of about 2 m. The vegetation was subject to a stepwise increasing flow discharge in order to achieve the condition for quasi-instantaneous uprooting for the two species and to investigate the unit processes which can be observed in a vegetated gravel bar. Bertoldi, W., A. Siviglia, S. Tettamanti, M. Toffolon, D. Vetsch, and S. Francalanci (2014), Modeling vegetation controls on fluvial morphological trajectories, Geophys. Res. Lett., 41, 7167-7175, doi:10.1002/2014GL061666. Edmaier, K, P Burlando, and P Perona. 2011. `Mechanisms of Vegetation Uprooting by Flow in Alluvial Non- Cohesive Sediment'. Hydrology and Earth System Sciences 15(5): 1615-1627.

  6. The Spacelab-Mir-1 "Greenhouse-2" experiment

    NASA Technical Reports Server (NTRS)

    Bingham, G. E.; Salisbury, F. B.; Campbell, W. F.; Carman, J. G.; Bubenheim, D. L.; Yendler, B.; Sytchev, V. N.; Levinskikh, M. A.; Podolsky, I. G.

    1996-01-01

    The Spacelab-Mir-1 (SLM-1) mission is the first docking of the Space Shuttle Atlantis (STS-71) with the Orbital Station Mir in June 1995. The SLM-1 "Greenhouse-2" experiment will utilize the Russian-Bulgarian-developed plant growth unit (Svet). "Greenhouse-2" will include two plantings (1) designed to test the capability of Svet to grow a crop of Superdwarf wheat from seed to seed, and (2) to provide green plant material for post-flight analysis. Protocols, procedures, and equipment for the experiment have been developed by the US-Russian science team. "Greenhouse-2" will also provide the first orbital test of a new Svet Instrumentation System (SIS) developed by Utah State University to provide near real time data on plant environmental parameters and gas-exchange rates. SIS supplements the Svet control and monitoring system with additional sensors for substrate moisture, air temperature, IR leaf temperature, light, oxygen, pressure, humidity, and carbon-dioxide. SIS provides the capability to monitor canopy transpiration and net assimilation of the plants growing in each vegetation unit (root zone) by enclosing the canopy in separate, retractable, ventilated leaf chambers. Six times during the seed-to-seed experiment, plant samples will be collected, leaf area measured, and plant parts fixed and/or dried for ground analysis. A second planting initiated 30 days before the arrival of a U.S. Shuttle [originally planned to be STS-71] is designed to provide green material at the vegetative development stage for ground analysis. [As this paper is being edited, the experiment has been delayed until after the arrival of STS-71.].

  7. The spacelab-mir-1 ``greenhouse-2'' experiment

    NASA Astrophysics Data System (ADS)

    Bingham, G. E.; Salisbury, F. B.; Campbell, W. F.; Carman, J. G.; Bubenheim, D. L.; Yendler, B.; Sytchev, V. N.; Berkovitch, Yu. A.; Levinskikh, M. A.; Podolsky, I. G.

    1996-01-01

    The Spacelab-Mir-1 (SLM-1) mission is the first docking of the Space Shuttle Atlantis (STS-71) with the Orbital Station Mir in June 1995. The SLM-1 ``Greenhouse-2'' experiment will utilize the Russian-Bulgarian-developed plant growth unit (Svet). ``Greenhouse-2'' will include two plantings (1) designed to test the capability of Svet to grow a crop of Superdwarf wheat from seed to seed, and (2) to provide green plant material for post-flight analysis. Protocols, procedures, and equipment for the experiment have been developed by the US-Russian science team. ``Greenhouse-2'' will also provide the first orbital test of a new Svet Instrumentation System (SIS) developed by Utah State University to provide near real time data on plant environmental parameters and gas-exchange rates. SIS supplements the Svet control and monitoring system with additional sensors for substrate moisture, air temperature, IR leaf temperature, light, oxygen, pressure, humidity, and carbon-dioxide. SIS provides the capability to monitor canopy transpiration and net assimilation of the plants growing in each vegetation unit (root zone) by enclosing the canopy in separate, retractable, ventilated leaf chambers. Six times during the seed-to-seed experiment, plant samples will be collected, leaf area measured, and plant parts fixed and/or dried for ground analysis. A second planting initiated 30 days before the arrival of a U.S. Shuttle [originally planned to be STS-71] is designed to provide green material at the vegetative development stage for ground analysis. [As this paper is being edited, the experiment has been delayed until after the arrival of STS-71.

  8. The Spacelab-Mir-1 "Greenhouse-2" experiment.

    PubMed

    Bingham, G E; Salisbury, F B; Campbell, W F; Carman, J G; Bubenheim, D L; Yendler, B; Sytchev, V N; Berkovitch YuA; Levinskikh, M A; Podolsky, I G

    1996-01-01

    The Spacelab-Mir-1 (SLM-1) mission is the first docking of the Space Shuttle Atlantis (STS-71) with the Orbital Station Mir in June 1995. The SLM-1 "Greenhouse-2" experiment will utilize the Russian-Bulgarian-developed plant growth unit (Svet). "Greenhouse-2" will include two plantings (1) designed to test the capability of Svet to grow a crop of Superdwarf wheat from seed to seed, and (2) to provide green plant material for post-flight analysis. Protocols, procedures, and equipment for the experiment have been developed by the US-Russian science team. "Greenhouse-2" will also provide the first orbital test of a new Svet Instrumentation System (SIS) developed by Utah State University to provide near real time data on plant environmental parameters and gas-exchange rates. SIS supplements the Svet control and monitoring system with additional sensors for substrate moisture, air temperature, IR leaf temperature, light, oxygen, pressure, humidity, and carbon-dioxide. SIS provides the capability to monitor canopy transpiration and net assimilation of the plants growing in each vegetation unit (root zone) by enclosing the canopy in separate, retractable, ventilated leaf chambers. Six times during the seed-to-seed experiment, plant samples will be collected, leaf area measured, and plant parts fixed and/or dried for ground analysis. A second planting initiated 30 days before the arrival of a U.S. Shuttle [originally planned to be STS-71] is designed to provide green material at the vegetative development stage for ground analysis. [As this paper is being edited, the experiment has been delayed until after the arrival of STS-71.

  9. The Spacelab-Mir-1 "Greenhouse-2" experiment

    NASA Technical Reports Server (NTRS)

    Bingham, G. E.; Salisbury, F. B.; Campbell, W. F.; Carman, J. G.; Bubenheim, D. L.; Yendler, B.; Sytchev, V. N.; Levinskikh, M. A.; Podolsky, I. G.

    1996-01-01

    The Spacelab-Mir-1 (SLM-1) mission is the first docking of the Space Shuttle Atlantis (STS-71) with the Orbital Station Mir in June 1995. The SLM-1 "Greenhouse-2" experiment will utilize the Russian-Bulgarian-developed plant growth unit (Svet). "Greenhouse-2" will include two plantings (1) designed to test the capability of Svet to grow a crop of Superdwarf wheat from seed to seed, and (2) to provide green plant material for post-flight analysis. Protocols, procedures, and equipment for the experiment have been developed by the US-Russian science team. "Greenhouse-2" will also provide the first orbital test of a new Svet Instrumentation System (SIS) developed by Utah State University to provide near real time data on plant environmental parameters and gas-exchange rates. SIS supplements the Svet control and monitoring system with additional sensors for substrate moisture, air temperature, IR leaf temperature, light, oxygen, pressure, humidity, and carbon-dioxide. SIS provides the capability to monitor canopy transpiration and net assimilation of the plants growing in each vegetation unit (root zone) by enclosing the canopy in separate, retractable, ventilated leaf chambers. Six times during the seed-to-seed experiment, plant samples will be collected, leaf area measured, and plant parts fixed and/or dried for ground analysis. A second planting initiated 30 days before the arrival of a U.S. Shuttle [originally planned to be STS-71] is designed to provide green material at the vegetative development stage for ground analysis. [As this paper is being edited, the experiment has been delayed until after the arrival of STS-71.].

  10. Heat and mass transfer of a low-pressure Mars greenhouse: Simulation and experimental analysis

    NASA Astrophysics Data System (ADS)

    Hublitz, Inka

    Biological life support systems based on plant growth offer the advantage of producing fresh food for the crew during a long surface stay on Mars. Greenhouses on Mars are also used for air and water regeneration and waste treatment. A major challenge in developing a Mars greenhouse is its interaction with the thin and cold Mars environment. Operating a Mars greenhouse at low interior pressure reduces the pressure differential across the structure and therefore saves structural mass as well as reduces leakage. Experiments were conducted to analyze the heating requirements as well as the temperature and humidity distribution within a small-scale greenhouse that was placed in a chamber simulating the temperatures, pressure and light conditions on Mars. Lettuce plants were successfully grown inside of the Mars greenhouse for up to seven days. The greenhouse atmosphere parameters, including temperature, total pressure, oxygen and carbon dioxide concentration were controlled tightly; radiation level, relative humidity and plant evapo-transpiration rates were measured. A vertical stratification of temperature and humidity across the greenhouse atmosphere was observed. Condensation formed on the inside of the greenhouse when the shell temperature dropped below the dew-point. During the night cycles frost built up on the greenhouse base plate and the lower part of the shell. Heat loss increased significantly during the night cycle. Due to the placement of the heating system and the fan blowing warm air directly on the upper greenhouse shell, condensation above the plants was avoided and therefore the photosynthetically active radiation at plant level was kept constant. Plant growth was not affected by the temperature stratification due to the tight temperature control of the warmer upper section of the greenhouse, where the lettuce plants were placed. A steady state and a transient heat transfer model of the low pressure greenhouse were developed for the day and the night

  11. The Effect of Soil Manganese on Japanese Larch (Larix Leptolepis Sieb. and Zucc.) Seedlings in the Greenhouse

    Treesearch

    Callie Jo Schweitzer; William E. Sharpe; Pamela J. Edwards

    1999-01-01

    Preliminary analysis of 9 year old Japanese larch trees and soil subjected to appliitions of triple ambient annual nitrogen (N) and sulfur (S) deposftfon revealed elevated available soil and foliar manganese (Mn) levels and decreased growth compared to controls. A greenhouse study was conducted in which Japanese larch seedlings were grown in geld collected soil...

  12. Translocation of arsenic contents in vegetables from growing media of contaminated areas.

    PubMed

    Baig, Jameel A; Kazi, Tasneem G

    2012-01-01

    The aim of this study was to evaluate the translocation of arsenic (As) by different vegetables grown in agricultural soil irrigated for long period with tube well water as test vegetable samples and compared those vegetables of same species grown in agricultural soil irrigated with fresh canal water marked as control vegetable samples. Moreover, the total and ethylene-diamine-tetra acetic acid (EDTA) extractable contents of As in soil irrigated by tube well and canal water were determined and correlate with total concentrations of As in edible parts of vegetables. Statistically significant correlations were obtained between the total and EDTA extractable fractions of As in soil. High level of total and EDTA extractable As were found in tested vegetable samples as compared to controlled vegetable samples. This investigation highlights the increased danger of growing vegetables in the agricultural land continuously irrigated by As contaminated water. Copyright © 2011 Elsevier Inc. All rights reserved.

  13. Greenhouse irrigation control system design based on ZigBee and fuzzy PID technology

    NASA Astrophysics Data System (ADS)

    Zhou, Bing; Yang, Qiliang; Liu, Kenan; Li, Peiqing; Zhang, Jing; Wang, Qijian

    In order to achieve the water demand information accurately detect of the greenhouse crop and its precision irrigation automatic control, this article has designed a set of the irrigated control system based on ZigBee and fuzzy PID technology, which composed by the soil water potential sensor, CC2530F256 wireless microprocessor, IAR Embedded Workbench software development platform. And the time of Irrigation as the output .while the amount of soil water potential and crop growth cycle as the input. The article depended on Greenhouse-grown Jatropha to verify the object, the results show that the system can irrigate timely and appropriately according to the soil water potential and water demend of the different stages of Jatropha growth , which basically meet the design requirements. Therefore, the system has broad application prospects in the amount of greenhouse crop of fine control irrigation.

  14. Greenhouse gas exchange in grasslands: impacts of climate, intensity of management and other factors

    NASA Astrophysics Data System (ADS)

    Smith, K. A.

    2003-04-01

    several Western European countries, very high rates of N application to both grazed grassland and to grass crops grown for winter feed have made these lands the principal source of N_2O. It has been estimated that 40% of global emissions of NO, a precursor of tropospheric ozone, come from grasslands and savannas. Global warming is expected to bring about substantial changes in the overall greenhouse gas exchange of grasslands, with a net loss of soil C as CO_2, and possibly enhanced N_2O emissions. Increased rainfall is predicted for some regions, and this can also be expected to give rise to increases in N_2O.

  15. Water loss and polyethylene glycol-mediated acclimatization of in vitro-grown seedlings of 5 cultivars of date palm (Phoenix dactylifera L.) plantlets.

    PubMed

    Zaid, A; Hughes, H

    1995-03-01

    Plantlets derived from shoot-tips of seedlings from five cultivars of date palm, Phoenix dactylifera L., were subjected to polyethylene glycol in liquid medium. Comparisons of water loss of detached leaves among in vitro-grown, polyethylene glycol-treated and greenhouse-grown plants showed significant differences with treatment for all cultivars studied. For each treatment, significant differences were also found among cultivars. The common result was that the percent of moisture loss of non-treated in vitro-grown plantlets was almost twice that of greenhouse-grown plants. Polyethylene glycol-treated plantlets showed a water loss of approximately 27%, similar to that of greenhouse plants as compared to an average of 40% in control plants. This demonstrates the possibility of using polyethylene glycol as an osmoticum for in vitro acclimatization of plantlets prior to transfer to soil.

  16. Characterization of the acylglycerols and resulting biodiesel derived from vegetable oil and microalgae (Thalassiosira pseudonana and Phaeodactylum tricornutum).

    PubMed

    Zendejas, Frank J; Benke, Peter I; Lane, Pamela D; Simmons, Blake A; Lane, Todd W

    2012-05-01

    Algal biofuels are a growing interest worldwide due to their potential in terms of sustainable greenhouse gas displacement and energy production. This article describes a comparative survey of biodiesel production and conversion yields of biodiesel via alkaline transesterification of acylglycerols extracted from the microalgae Thalassiosira pseudonana and Phaeodactylum tricornutum, grown under silicate or nitrate limitation, and that of model vegetable oils: soybean, and rapeseed oil. Acylglycerols were extracted with n-hexane and the total yield per biomass was determined by gravimetric assay. Under our conditions, the total acylglycerol yield from the microalgae studied was 13-18% of total dry weight. The biodiesel samples were analyzed using gas chromatography-flame ionization detector to determine quantitative information of residual glycerol, mono-, di-, and tri-acylglycerol concentrations in the biodiesel. All of the algal-based biodiesel demonstrated less mono-, di-, and tri-acylglycerol concentrations than the vegetable-based biodiesel under identical transesterification conditions. The fatty acid compositions of all the feedstock oils and their resultant biodiesel were also analyzed and reported. Based on the fatty acid methyl ester compositions of our samples we qualitatively assessed the suitability of the algal-derived biodiesel in terms of cetane number (CN), cold-flow properties, and oxidative stability.

  17. Scientists Inspect Plant Grown onboard the ISS in 2002

    NASA Technical Reports Server (NTRS)

    2003-01-01

    The Advanced Astroculture (tm) unit is growing plants on its second flight on the International Space Station. Dr. Weijia Zhou (left), director of the Wisconsin Center for Space Automation and Robotics at the University of Wisconsin-Madison, inspects soybeans grown in the plant growth unit aboard ISS in 2002. Coating technology is used inside the miniature plant greenhouse to remove ethylene, a chemical produced by plant leaves that can cause plants to mature too quickly. This same coating technology is used in a new anthrax-killing device. The Space Station experiment is managed by the Space Partnership Development Program at NASA's Marshall Space Flight Center in Huntsville, Ala.

  18. Teleconsultations reduce greenhouse gas emissions.

    PubMed

    Oliveira, Tiago Cravo; Barlow, James; Gonçalves, Luís; Bayer, Steffen

    2013-10-01

    Health services contribute significantly to greenhouse gas emissions. New models of delivering care closer to patients have the potential to reduce travelling and associated emissions. We aimed to compare the emissions of patients attending a teleconsultation - an outpatient appointment using video-conferencing equipment - with those of patients attending a face-to-face appointment. We estimated the total distances travelled and the direct and indirect greenhouse gas emissions for 20,824 teleconsultations performed between 2004 and 2011 in Alentejo, a Portuguese region. These were compared to the distances and emissions that would have resulted if teleconsultations were not available and patients had to attend face-to-face outpatient appointments. Estimates were calculated using survey data on mode of transport, and national aggregate data for car engine size and fuel. A sensitivity analysis using the lower and upper quartiles for survey distances was performed. Teleconsultations led to reductions in distances and emissions of 95%. 2,313,819 km of travelling and 455 tonnes of greenhouse gas emissions were avoided (22 kg of carbon dioxide equivalent per patient). The incorporation of modes of transport and car engine size and fuel in the analysis led to emission estimates which were 12% smaller than those assuming all patients used an average car. The availability of remote care services can significantly reduce road travel and associated emissions. At a time when many countries are committed to reducing their carbon footprint, it is desirable to explore how these reductions could be incorporated into technology assessments and economic evaluations.

  19. Methane Greenhouses and Anti-Greenhouses During the Precambrian

    NASA Astrophysics Data System (ADS)

    Kasting, J. F.; Pavlov, A. A.

    2003-12-01

    Methane was arguably an important greenhouse gas during the Archean and early Paleoproterozoic Eras, prior to the rise of O2 at ~2.3 Ga (1,2). Atmospheric CH4 concentrations of 1000 ppmv or more are predicted, assuming that methanogenic bacteria evolved early and that they were widely distributed in the prevailing anaerobic biosphere (2,3). Indeed, previous models (1-3) may have underestimated both the concentration of CH4 and the greenhouse effect itself at this time. Knauth and Lowe (4) have used oxygen isotopes in cherts to argue that the mean surface temperature at 3.2-3.5 Ga was between 55oC and 85oC. The Sun is thought to have been some 23 percent dimmer at that time (5), so this would have required substantial greenhouse warming by both CH4 and CO2. Further constraints are imposed by the formation of hydrocarbon haze, and an accompanying "anti-greenhouse effect", if the CH4 concentration exceeds that of CO2 (2). Thus, only certain combinations of CH4 and CO2 are possible. The rise of O2 at 2.3 Ga destabilized the methane greenhouse, leading to widespread (possibly global) glaciation (1,6). The next 1.5 billion years were warm, however, as evidenced by the absence of glacial deposits and the continuing high temperatures implied by O isotopes in cherts (7). CH4 levels could have remained relatively high during this time, 20-100 ppmv, as a consequence of low concentrations of dissolved O2 and sulfate in the deep oceans, and increased recycling of organic matter by fermentation and methanogenesis (8,9). An increase in either O2 or dissolved sulfate at around 0.75 Ga may have once again decreased atmospheric CH4 levels and triggered the widespread Neoproterozoic glaciations. References: 1. Pavlov, A. A., Kasting, J. F., Brown, L. L., Rages, K. A. & Freedman, R. J. Geophys. Res. 105, 11,981-11,990 (2000). 2. Pavlov, A. A., Kasting, J. F. & Brown, L. L. J. Geophys. Res. 106, 23,267-23,287 (2001). 3. Kasting, J. F., Pavlov, A. A. & Siefert, J. L. Origins of Life

  20. False advertising in the greenhouse?

    NASA Astrophysics Data System (ADS)

    Banse, K.

    1991-12-01

    Most scientists are convinced of the importance of their own research subjects. Broecker [1991] has deplored the temptation, if not the tendency, to go overboard and exaggerate this importance once funding enters the mind. In particular, he alleges inflated or even false claims by biological (and other) oceanographers regarding the relevance of their research to the "greenhouse effect," caused by the anthropogenic enhancement of the atmospheric CO2 content. He writes [Broecker, 1991, p. 191]: "In my estimation, on any list of subjects requiring intense study with regard to the prediction of the consequences of CO2 buildup in the atmosphere, I would place marine biological cycles near the bottom."

  1. Climate Change and Greenhouse Gases

    NASA Technical Reports Server (NTRS)

    Ledley, Tamara S.; Sundquist, Eric; Schwartz, Stephen; Hall, Dorothy K.; Fellows, Jack; Killeen, Timothy

    1999-01-01

    The American Geophysical Union (AGU), as a scientific organization devoted to research on the Earth and space sciences, provides current scientific information to the public on issues pertinent to geophysics. The Council of the AGU approved a position statement on Climate Change and Greenhouse Gases in December 1998. The statement, together with a short summary of the procedures that were followed in its preparation, review, and adoption were published in the February 2, 1999 issue of Eos ([AGU, 1999]. The present article reviews scientific understanding of this issue as presented in peer-reviewed publications that serves as the underlying basis of the position statement.

  2. Solar energy collection/storage system for greenhouses: observed and simulated performance

    SciTech Connect

    Willits, D.H.; Chandra, P.; Miller, C.H.

    1981-01-01

    Performance data are pesented and some operating characteristics of a solar energy collection/storage system for greenhouses are examined. The system uses an external rock storage connected to a 6.7 x 12.2 m, fiberglass-covered greenhouse to hold excess energy collected with the greenhouse during the day for use in supplementing heating requirements during periods of deficit. Fuel consumption in the test house is compared to that in an identical, unmodified control house for three growing seasons over 1 1/2 years. Tomatoes were grown for two of the three seasons (Fall 78 and Spring 79) and lettuce was grown during the third (Fall 79). The data indicate that a savings of 31.1% was achieved for the Fall 79 season as compared to 16.9% for the same period of the previous year. This improvement is attributed to the reduced operating temperature and evapotranspiration load of the lettuce crop as well as to some improvements made to the system during the summer of 1979. Increased electrical consumption required to pump the air through the rock storage was observed to be a small percentage of the total energy saved. Yield data for the three growing seasons are pesented but no conclusions are drawn. Simulation studies performed in an effort to answer some pertinent questions about the performance of the system indicate that: (1) the uncontrolled release of heat from internal storages can be detrimental during periods when little or no heating is required resulting in higher greenhouse temperatures, and therefore higher plant respiration rates, than houses using external storages; and (2) better performance can be expected with double polyethylene-covered greenhouses than with fiberglass greenhouses owing to reduced nighttime heating load and increased solar energy collection.

  3. [Risk of reproductive disorders in greenhouse workers].

    PubMed

    Jurewicz, Joanna; Hanke, Wojciech

    2007-01-01

    This study reviews the evidence on the association between work in greenhouses and reproductive disorders. The analysis indicate that employment in greenhouses may increase the risk of birth defects, preterm delivery and spontaneous abortion, and also may affect birth weight. The obtained results showed that employment in the agriculture production sector (greenhouses) of more than 10 years decreased the median sperm concentration in men. The data on the effect of employment in greenhouses on the time to pregnancy are unequivocal, but most of them suggest that there is a relationship between the decreased fecundity ratio and greenhouse work, mostly due to exposure to pesticides. The literature review indicates a great need to increase awareness among greenhouse workers occupationally exposed to pesticides about potential negative effects of these chemicals on their health.

  4. Reproductive Ontogeny of Wheat Grown on the MIR Space Station

    NASA Technical Reports Server (NTRS)

    Bubenheim, David L.; Stieber, Joseph

    1997-01-01

    The reproductive ontogeny of 'Super-Dwarf' wheat grown on the space station Mir is chronicled from the vegetative phase through flower development. Changes in the apical meristem associated with transition From the vegetative phase to floral initiation and development of the reproductive spike were all typical of 'Super Dwarf' wheat up to the point of anthesis. Filament elongation, which characteristically occurs just prior to anthesis and moves the anthers through the stigmatic branches thus facilitating pollination, did no1 xcur in the flowers of spikes grown on Mir. While development of spikes on tillers typically occurs later :han that of spikes on the main stem, all flowers appear to be arrested at the same developmental point.

  5. THE GREENHOUSE EFFECT OF THE ARCTIC ATMOSPHERE.

    DTIC Science & Technology

    Some of this absorbed heat is radiated back to the earth’s surface. This process is generally called the ’ greenhouse effect ’ of the atmosphere...of the terrestrial radiation escapes through the atmosphere. The values for two equations representing the ’ greenhouse effect ’ are discussed. Both...show very small geographical and temporal variations. The atmospheric greenhouse effect is remarkably stable in all latitudes and climatic zones

  6. Effect of Mulch Surface Color on Root-knot of Tomato Grown in Simulated Planting Beds.

    PubMed

    Fortnum, B A; Kasperbauer, M J; Decoteau, D R

    2000-03-01

    The effect of different-colored polyethylene mulches on quantity and spectra of reflected light, plant morphology, and root-knot disease was studied in tomato (Lycopersicon esculentum) grown in simulated planting beds. Tomato plants were inoculated with Meloidogyne incognita at initial populations (Pi) of 0, 1,000, 10,000, or 50,000 eggs/plant, and grown in a greenhouse for 50 days over white, red, or black mulch. Soil temperature was kept constant among the mulch treatments by placing an insulation barrier between the colored mulch and the soil surface. Soil temperature varied less than 0.5 degrees C between soil chambers at solar noon. Tomatoes grown over white mulch received more reflected photosynthetic light and had greater shoot weights (27%), root weights (32%), and leaf area (20%) than plants grown over black mulch. Plants grown over red mulch received a higher far-red-to-red ratio in the reflected light. Mulch color altered the plant's response to root-knot nematode infection by changing the distribution of mass in axillary shoots. At high Pi, axillary leaf area and leaf weight were greater in tomato grown over white mulch than when grown over red mulch. The root-gall index was lower for plants grown over white mulch than similar plants grown over red mulch.

  7. Effect of Mulch Surface Color on Root-knot of Tomato Grown in Simulated Planting Beds

    PubMed Central

    Fortnum, B. A.; Kasperbauer, M. J.; Decoteau, D. R.

    2000-01-01

    The effect of different-colored polyethylene mulches on quantity and spectra of reflected light, plant morphology, and root-knot disease was studied in tomato (Lycopersicon esculentum) grown in simulated planting beds. Tomato plants were inoculated with Meloidogyne incognita at initial populations (Pi) of 0, 1,000, 10,000, or 50,000 eggs/plant, and grown in a greenhouse for 50 days over white, red, or black mulch. Soil temperature was kept constant among the mulch treatments by placing an insulation barrier between the colored mulch and the soil surface. Soil temperature varied less than 0.5 °C between soil chambers at solar noon. Tomatoes grown over white mulch received more reflected photosynthetic light and had greater shoot weights (27%), root weights (32%), and leaf area (20%) than plants grown over black mulch. Plants grown over red mulch received a higher far-red-to-red ratio in the reflected light. Mulch color altered the plant's response to root-knot nematode infection by changing the distribution of mass in axillary shoots. At high Pi, axillary leaf area and leaf weight were greater in tomato grown over white mulch than when grown over red mulch. The root-gall index was lower for plants grown over white mulch than similar plants grown over red mulch. PMID:19270954

  8. Re-assessment of net energy production and greenhouse gas emissions avoidance after 40 years of photovoltaics development

    PubMed Central

    Louwen, Atse; van Sark, Wilfried G. J. H. M.; Faaij, André P. C.; Schropp, Ruud E. I.

    2016-01-01

    Since the 1970s, installed solar photovoltaic capacity has grown tremendously to 230 gigawatt worldwide in 2015, with a growth rate between 1975 and 2015 of 45%. This rapid growth has led to concerns regarding the energy consumption and greenhouse gas emissions of photovoltaics production. We present a review of 40 years of photovoltaics development, analysing the development of energy demand and greenhouse gas emissions associated with photovoltaics production. Here we show strong downward trends of environmental impact of photovoltaics production, following the experience curve law. For every doubling of installed photovoltaic capacity, energy use decreases by 13 and 12% and greenhouse gas footprints by 17 and 24%, for poly- and monocrystalline based photovoltaic systems, respectively. As a result, we show a break-even between the cumulative disadvantages and benefits of photovoltaics, for both energy use and greenhouse gas emissions, occurs between 1997 and 2018, depending on photovoltaic performance and model uncertainties. PMID:27922591

  9. Re-assessment of net energy production and greenhouse gas emissions avoidance after 40 years of photovoltaics development

    NASA Astrophysics Data System (ADS)

    Louwen, Atse; van Sark, Wilfried G. J. H. M.; Faaij, André P. C.; Schropp, Ruud E. I.

    2016-12-01

    Since the 1970s, installed solar photovoltaic capacity has grown tremendously to 230 gigawatt worldwide in 2015, with a growth rate between 1975 and 2015 of 45%. This rapid growth has led to concerns regarding the energy consumption and greenhouse gas emissions of photovoltaics production. We present a review of 40 years of photovoltaics development, analysing the development of energy demand and greenhouse gas emissions associated with photovoltaics production. Here we show strong downward trends of environmental impact of photovoltaics production, following the experience curve law. For every doubling of installed photovoltaic capacity, energy use decreases by 13 and 12% and greenhouse gas footprints by 17 and 24%, for poly- and monocrystalline based photovoltaic systems, respectively. As a result, we show a break-even between the cumulative disadvantages and benefits of photovoltaics, for both energy use and greenhouse gas emissions, occurs between 1997 and 2018, depending on photovoltaic performance and model uncertainties.

  10. Re-assessment of net energy production and greenhouse gas emissions avoidance after 40 years of photovoltaics development.

    PubMed

    Louwen, Atse; van Sark, Wilfried G J H M; Faaij, André P C; Schropp, Ruud E I

    2016-12-06

    Since the 1970s, installed solar photovoltaic capacity has grown tremendously to 230 gigawatt worldwide in 2015, with a growth rate between 1975 and 2015 of 45%. This rapid growth has led to concerns regarding the energy consumption and greenhouse gas emissions of photovoltaics production. We present a review of 40 years of photovoltaics development, analysing the development of energy demand and greenhouse gas emissions associated with photovoltaics production. Here we show strong downward trends of environmental impact of photovoltaics production, following the experience curve law. For every doubling of installed photovoltaic capacity, energy use decreases by 13 and 12% and greenhouse gas footprints by 17 and 24%, for poly- and monocrystalline based photovoltaic systems, respectively. As a result, we show a break-even between the cumulative disadvantages and benefits of photovoltaics, for both energy use and greenhouse gas emissions, occurs between 1997 and 2018, depending on photovoltaic performance and model uncertainties.

  11. Could plants help tame the greenhouse

    SciTech Connect

    Baskin, Y.

    1993-03-19

    It's easy to see how climate change might affect the globe's vegetation, driving hardwood forests into regions now covered with evergreens and causing deserts to shift. It's less easy to picture the other side of the coin: biology's impact on the atmosphere. So mathematician Berrien Moore III of the University of New Hampshire, who heads the International Geosphere-Biosphere Program task force on global analysis, interpretation, and modeling, staged a simple demonstration. He modeled the effects of a biosphere fertilized by increased CO[sub 2] - and found that it could first help, then hinder, human efforts to slow the buildup of greenhouse gases. To simulate such a biotic carbon sink, Moore combined a simple model of CO[sub 2] uptake by the ocean with an equally simple model of its uptake by photosynthesis on land and its release by deforestation and plant decay. He then forced this simple ocean-atmosphere-vegetation model with fossil fuel CO[sub 2] emissions from 1860 to the present. As expected, his model ended up with too much carbon in the atmosphere. So he turned up photosynthesis, fertilizing plant growth in his model, until the rate of CO[sub 2] buildup just matched the observed increase. Moore then explored how this terrestrial carbon sink would respond if the CO[sub 2] buildup slowed. The result: If you were to cap the rate of CO[sub 2] emissions from fossil fuel burning, [this terrestrial] sink would reduce the atmospheric lifetime of CO[sub 2] by a factor of four or five. This cleansing effect would operate on timescales of years or decades, compared with centuries for the ocean, says Moore - fast enough to aid human efforts to slow the CO[sub 2] buildup. However, it doesn't do it forever. If at some point emissions cuts and the terrestrial sink succeeded in reducing atmospheric CO[sub 2], plant growth would drop and CO[sub 2] levels would bounce back up as all the extra biomass rotted away.

  12. Daily intake of heavy metals and nitrate through greenhouse cucumber and bell pepper consumption and potential health risks for human.

    PubMed

    Khoshgoftarmanesh, Amir H; Aghili, Forough; Sanaeiostovar, Azadeh

    2009-01-01

    Limited information is available on the health quality of greenhouse vegetables. Lead, cadmium, nickel, chromium, and nitrate (NO3-) concentrations in greenhouse cucumber (Cucumis sativa L.) and bell pepper (Capsicum annuum L.) and their dietary intakes were determined. The non-cancer risk for NO3- was determined using the non-cancer hazard quotient. Lead non-cancer risk in children was calculated using the Integrated Exposure-Uptake Biokinetic model. Higher concentrations of cadmium, lead, and chromium were found in bell pepper than cucumber. The mean NO3- concentration in the greenhouse cucumber was about 2.7 times higher than the World Health Organization standard limit. Cadmium, lead, nickel, and chromium daily intake for different populations groups through consumption of the vegetables were < 0.01-0.04, 0.35-1.00, 0.03-0.24, and 0.05-0.27 microg/g, respectively. The dietary intake of NO3- for adult was greater than children. Elevated lead and NO3- concentrations in the greenhouse vegetables are important concerns for consumers. Potential health quality problems in greenhouse products have to be considered.

  13. Observational determination of the greenhouse effect

    NASA Technical Reports Server (NTRS)

    Raval, A.; Ramanathan, V.

    1989-01-01

    Satellite measurements are used to quantify the atmospheric greenhouse effect, defined here as the infrared radiation energy trapped by atmospheric gases and clouds. The greenhouse effect is found to increase significantly with sea surface temperature. The rate of increase gives compelling evidence for the positive feedback between surface temperature, water vapor and the greenhouse effect; the magnitude of the feedback is consistent with that predicted by climate models. This study demonstrates an effective method for directly monitoring, from space, future changes in the greenhouse effect.

  14. Engineering concepts for inflatable Mars surface greenhouses

    NASA Technical Reports Server (NTRS)

    Hublitz, I.; Henninger, D. L.; Drake, B. G.; Eckart, P.

    2004-01-01

    A major challenge of designing a bioregenerative life support system for Mars is the reduction of the mass, volume, power, thermal and crew-time requirements. Structural mass of the greenhouse could be saved by operating the greenhouse at low atmospheric pressure. This paper investigates the feasibility of this concept. The method of equivalent system mass is used to compare greenhouses operated at high atmospheric pressure to greenhouses operated at low pressure for three different lighting methods: natural, artificial and hybrid lighting. c2004 COSPAR. Published by Elsevier Ltd. All rights reserved.

  15. Engineering Concepts for Inflatable Mars Surface Greenhouses

    NASA Astrophysics Data System (ADS)

    Hublitz, I.; Henninger, D.; Drake, G.; Eckart, P.

    An inflatable greenhouse is an important component of the Mars mission infrastructure as plant -based life support systems offer self-sufficiency and possibly cost reduction. Resupply is prohibitive for long duration Mars missions as it increases the launching mass and consequently the launching costs. Risks for the astronauts are als o increased by relying on frequent resupply from Earth. Greenhouses are not only used for the production of edible biomass but also as air and water regeneration processors. This study provides designs and engineering considerations for inflatable Mars surface greenhouses including structural, material, lighting method and thermal aspects. Challenges for the thermal control system are presented by showing the diurnal heat gain/loss for the various greenhouse design options. Structural mass savings for operating greenhouses at lower pressures are investigated. The method of equivalent system mass is used in order to compare greenhouses operated at high pressure to greenhouses operated at low pressure for three different lighting methods: natural, artificial and hybrid lighting. This method evaluates the impact of the greenhouse implementation to other systems by reducing the physical quantities mass, power, cooling and crew-time requirements to one single parameter mass, which is the primary driver of Mars mission costs. The design comparison evaluation is a further approach to compare the different greenhouse design options regarding not only the equivalent system mass but also other important factors such as the technology maturity, safety and flexibility to mission modifications. Alternative design ideas will be presented and future work issues will be defined.

  16. Engineering concepts for inflatable Mars surface greenhouses

    NASA Technical Reports Server (NTRS)

    Hublitz, I.; Henninger, D. L.; Drake, B. G.; Eckart, P.

    2004-01-01

    A major challenge of designing a bioregenerative life support system for Mars is the reduction of the mass, volume, power, thermal and crew-time requirements. Structural mass of the greenhouse could be saved by operating the greenhouse at low atmospheric pressure. This paper investigates the feasibility of this concept. The method of equivalent system mass is used to compare greenhouses operated at high atmospheric pressure to greenhouses operated at low pressure for three different lighting methods: natural, artificial and hybrid lighting. c2004 COSPAR. Published by Elsevier Ltd. All rights reserved.

  17. The Alaska vegetation classification.

    Treesearch

    L.A. Viereck; C.T. Dyrness; A.R. Batten; K.J. Wenzlick

    1992-01-01

    The Alaska vegetation classification presented here is a comprehensive, statewide system that has been under development since 1976. The classification is based, as much as possible, on the characteristics of the vegetation itself and is designed to categorize existing vegetation, not potential vegetation. A hierarchical system with five levels of resolution is used...

  18. Greenhouse gas emissions of different land uses in the delta region of Red River, Vietnam

    NASA Astrophysics Data System (ADS)

    Zhou, Minghua; Ha, Thu; An, Ngo The; Brüggemann, Nicolas

    2017-04-01

    Agricultural activities are responsible for up to a third of total anthropogenic GHG emissions. The subtropical/tropical delta areas of the large rivers in Southeast Asia are long-term history agricultural regions in the world. However, due to lack of field measurements, the estimation of the contribution of agro-ecosystems in the subtropical/tropical delta areas to global greenhouse gas emissions remains largely uncertain. Here, we conducted field experiments since January 2016 to quantify greenhouse gases (CO2, CH4 and N2O) emissions from four agricultural land uses of annual rice-rice, rice-vegetable, continuous vegetable system and fish pond in Red River delta region of Vietnam by using the transparent static chamber-gas chromatography technique. Higher N2O emissions were observed in the rice-vegetable and continuous vegetable systems, while lower N2O emissions were observed in the rice-rice and find pond systems. Compared to rice-rice system the cumulative N2O fluxes were on average twenty-fold higher in the rice-vegetable and continuous vegetable systems but significantly lower (75%) in the fish pond. Overall the net CO2 sinks were observed in the rice-rice system while other three land uses of rice-vegetable, continuous vegetable and fish pond acted as the net CO2 sources. The rice-rice and fish pond showed net CH4 emissions while variations of CH4 emissions (i.e. shifting between sources and sinks) along variations of soil moisture and temperature were observed in rice-vegetable and continuous vegetable systems. Compared to rice-rice system, the cumulative CH4 fluxes were significantly decreased by 100% for continuous vegetable system, 94% for rice-vegetable system and 89% for fish pond. Overall, the data suggest that conversion of traditional rice-rice paddy system to rice-vegetable, continuous vegetable system and find pond, which are currently undergoing driven by the economical requests and environmental changes (e.g., salinity intrusion) in this delta

  19. Project of conveyer-type space greenhouse for cosmonauts' supply with vitamin greenery

    NASA Astrophysics Data System (ADS)

    Berkovich, Yu. A.; Krivobok, N. M.; Sinyak, Yu. E.

    1998-11-01

    Design and advantages of conveyer-type growth chamber PHYTOCYCLE with a cylindrical crop surface are featured. Based on the results of testing, an experimental prototype of conveyer-type vegetable greenhouse VITACYCLE for space vehicles is being developed at the SSC-IBMP in conjunction with a number of institutions of the Russian space industry to provide space crews with fresh greenery. Rated daily production of the greenhouse is 150 g of eatable biomass with power consumption of 1 kW. The system is to be mounted within the life support module of international space station Alpha (ISSA). Design of the greenhouse is outlined. Brief description, state-of-the-art, and further plans regarding VITACYCLE elaboration and construction are presented.

  20. Characterization of global vegetation using AVHRR data

    NASA Astrophysics Data System (ADS)

    Kiang, Richard K.

    1998-03-01

    Increase in the levels of carbon dioxide and other greenhouse gases over the next half-century may result in an increase in global mean temperature. The recent discoveries of possible advance of arctic tree line into the tundra and earlier greening of northern vegetation provide additional warnings that global warming may indeed be occurring. On the Earth surface, land cover and its changes affect the coupling between the biosphere and the atmosphere, and control many important Earth system processes. Satellite remote sensing provides long-term, repeated coverage over extended area and is the essential data source for monitoring climate changes. An Advanced Very-High Resolution Radiometer (AVHRR) Pathfinder dataset from 1987, in 1 degree latitude-longitude resolution, is used in this study. Two reflective channels, two thermal channels, and Normalized Difference Vegetation Index are the input parameters. In conjunction with a global vegetation ground truth, a multi-layer neural network is trained and used for global vegetation characterization. As the same type of vegetation may appear very differently over different parts of the Earth at any given time, global classification is more difficult than local classification. It is shown that a multitemporal approach, in which data from multiple dates are used, may improve the accuracy.

  1. DayCent model simulations for estimating soil carbon dynamics and greenhouse gas fluxes from agricultural production systems

    USDA-ARS?s Scientific Manuscript database

    DayCent is a biogeochemical model of intermediate complexity used to simulate carbon, nutrient, and greenhouse gas fluxes for crop, grassland, forest, and savanna ecosystems. Model inputs include: soil texture and hydraulic properties, current and historical land use, vegetation cover, daily maximum...

  2. Factors Affecting Greenhouse Gas Emissions From Rice Agriculture

    NASA Astrophysics Data System (ADS)

    Shearer, M. J.; Xiong, Z.; Khalil, M. K.

    2007-12-01

    Experiments have shown that a few factors control the emissions of methane from rice fields. Among the most significant factors are water management and soil amendments. Continuous flooding and organic fertilizers result in the highest emissions of methane while intermittent flooding and use of nitrogen fertilizers produce more nitrous oxide. We measured fluxes of methane and nitrous oxide from tubs planted with rice grown in a greenhouse at Portland State University. We used classical factorial experimental design to calculate interactions between water management, nitrogen fertilizer application, and organic matter (chopped rice straw) for emission of methane and nitrous oxide. We will discuss the results of three years of experiments. This research was supported by the Office of Science (BER), US Department of Energy, Grant No. DE-FG02- 04ER63913.

  3. Native Grasses as a Management Alternative on Vegetated Closure Caps

    NASA Astrophysics Data System (ADS)

    Kwit, Charles; Collins, Beverly

    2008-06-01

    Capped waste sites often are vegetated with commercial turf grasses to increase evapotranspiration and prevent erosion and possible exposure of the barrier. Fertilizer, frequent watering, and mowing may be required to establish the turf grass and prevent invasion by trees and shrubs. Oldfield vegetation of grasses and forbs is a possible sustainable alternative to turf grass communities. To determine if oldfield vegetation can establish on caps, we (1) compared establishment of a dominant oldfield grass and a commercial turf grass under different combinations of new closure cap management: spring or summer planting and presence or absence of amendments to alleviate drought (watering, mulch) or increase soil fertility (fertilizer, lime, a nitrogen-fixing legume); (2) surveyed existing caps to determine if oldfield species establish naturally; and (3) performed a greenhouse experiment to compare growth of two native grasses under low and amended (added water, soil nutrients) conditions. Both the commercial grass and oldfield species established under new cap conditions; fertilizer, water, and mulch improved vegetation establishment in spring or summer, but legumes decreased grass cover. In the greenhouse, both native grasses grew best with amendments; however, substantial stem and root length were obtained with no fertilizer and only once-weekly watering. Existing vegetated caps supported planted grasses and naturally established oldfield species. Overall, the results indicate native grasses can establish on new caps and oldfields can serve as a management model; further work is needed to determine the management strategy to maintain herbaceous vegetation and slow woody species invasion.

  4. Native grasses as a management alternative on vegetated closure caps.

    PubMed

    Kwit, Charles; Collins, Beverly

    2008-06-01

    Capped waste sites often are vegetated with commercial turf grasses to increase evapotranspiration and prevent erosion and possible exposure of the barrier. Fertilizer, frequent watering, and mowing may be required to establish the turf grass and prevent invasion by trees and shrubs. Oldfield vegetation of grasses and forbs is a possible sustainable alternative to turf grass communities. To determine if oldfield vegetation can establish on caps, we (1) compared establishment of a dominant oldfield grass and a commercial turf grass under different combinations of new closure cap management: spring or summer planting and presence or absence of amendments to alleviate drought (watering, mulch) or increase soil fertility (fertilizer, lime, a nitrogen-fixing legume); (2) surveyed existing caps to determine if oldfield species establish naturally; and (3) performed a greenhouse experiment to compare growth of two native grasses under low and amended (added water, soil nutrients) conditions. Both the commercial grass and oldfield species established under new cap conditions; fertilizer, water, and mulch improved vegetation establishment in spring or summer, but legumes decreased grass cover. In the greenhouse, both native grasses grew best with amendments; however, substantial stem and root length were obtained with no fertilizer and only once-weekly watering. Existing vegetated caps supported planted grasses and naturally established oldfield species. Overall, the results indicate native grasses can establish on new caps and oldfields can serve as a management model; further work is needed to determine the management strategy to maintain herbaceous vegetation and slow woody species invasion.

  5. Biodiversity of Terrestrial Vegetation during Past Warm Periods

    NASA Astrophysics Data System (ADS)

    Davies-Barnard, T.; Valdes, P. J.; Ridgwell, A.

    2016-12-01

    Previous modelling studies of vegetation have generally used a small number of plant functional types to understand how the terrestrial biosphere responds to climate changes. Whilst being useful for understanding first order climate feedbacks, this climate-envelope approach makes a lot of assumptions about past vegetation being very similar to modern. A trait-based method has the advantage for paleo modelling in that there are substantially less assumptions made. In a novel use of the trait-based dynamic vegetation model JeDi, forced with output from climate model HadCM3, we explore past biodiversity and vegetation carbon changes. We use JeDi to model an optimal 2000 combinations of fifteen different traits to enable assessment of the overall level of biodiversity as well as individual growth strategies. We assess the vegetation shifts and biodiversity changes in past greenhouse periods to better understand the impact on the terrestrial biosphere. This work provides original insights into the response of vegetation and terrestrial carbon to climate and hydrological changes in high carbon dioxide climates over time, including during the Late Permian and Cretaceous. We evaluate how the location of biodiversity hotspots and species richness in past greenhouse climates is different to the present day.

  6. Monitoring vegetation water uptake in a semiarid riparian corridor

    NASA Astrophysics Data System (ADS)

    Robinson, J.; Ochoa, C. G.; Leonard, J.

    2015-12-01

    With a changing global climate and growing demand for water throughout the world, responsible and sustainable land and water resource management practices are becoming increasingly important. Accounting for the amount of water used by riparian vegetation is a critical element for better managing water resources in arid and semiarid environments. The objective of this study was to determine water uptake by selected riparian vegetative species in a semiarid riparian corridor in North-Central Oregon. Exo-skin sap flow sensors (Dynamax, Houston, TX, U.S.A.) were used to measure sap flux in red alder (Alnus rubra) trees, the dominant overstory vegetation at the field site. Xylem sap flow data was collected from selected trees at the field site and in a greenhouse setting. Transpiration rates were determined based on an energy balance method, which makes it possible to estimate the mass flow of sap by measuring the velocity of electrical heat pulses through the plant stem. Preliminary field results indicate that red alder tree branches of about 1 inch diameter transpire between 2 and 6 kg of water/day. Higher transpiration rates of up to 7.3 kg of water/day were observed under greenhouse conditions. Streamflow and stream water temperature, vegetation characteristics, and meteorological data were analyzed in conjunction with transpiration data. Results of this study provide insight on riparian vegetation water consumption in water scarce ecosystems. This study is part of an overarching project focused on climate-vegetation interactions and ecohydrologic processes in arid and semiarid landscapes.

  7. Quantification and Controls of Wetland Greenhouse Gas Emissions

    SciTech Connect

    McNicol, Gavin

    2016-05-10

    Wetlands cover only a small fraction of the Earth’s land surface, but have a disproportionately large influence on global climate. Low oxygen conditions in wetland soils slows down decomposition, leading to net carbon dioxide sequestration over long timescales, while also favoring the production of redox sensitive gases such as nitrous oxide and methane. Freshwater marshes in particular sustain large exchanges of greenhouse gases under temperate or tropical climates and favorable nutrient regimes, yet have rarely been studied, leading to poor constraints on the magnitude of marsh gas sources, and the biogeochemical drivers of flux variability. The Sacramento-San Joaquin Delta in California was once a great expanse of tidal and freshwater marshes but underwent drainage for agriculture during the last two centuries. The resulting landscape is unsustainable with extreme rates of land subsidence and oxidation of peat soils lowering the surface elevation of much of the Delta below sea level. Wetland restoration has been proposed as a means to slow further subsidence and rebuild peat however the balance of greenhouse gas exchange in these novel ecosystems is still poorly described. In this dissertation I first explore oxygen availability as a control on the composition and magnitude of greenhouse gas emissions from drained wetland soils. In two separate experiments I quantify both the temporal dynamics of greenhouse gas emission and the kinetic sensitivity of gas production to a wide range of oxygen concentrations. This work demonstrated the very high sensitivity of carbon dioxide, methane, and nitrous oxide production to oxygen availability, in carbon rich wetland soils. I also found the temporal dynamics of gas production to follow a sequence predicted by thermodynamics and observed spatially in other soil or sediment systems. In the latter part of my dissertation I conduct two field studies to quantify greenhouse gas exchange and understand the carbon sources for

  8. Modeling, Characterization and Analysis of the dynamic behavior of heat transfers through polyethylene and glass walls of Greenhouses

    NASA Astrophysics Data System (ADS)

    Bibi-Triki, N.; Bendimerad, S.; Chermiti, A.; Mahdjoub, T.; Draoui, B.; Abène, A.

    The conventional agricultural tunnel greenhouse is highly widespread in Mediterranean countries, despite the shortcomings it presents, specifically the overheating during the day and the intense cooling at night. This can sometimes lead to an internal thermal inversion. The chapel-shaped glass greenhouse is relatively more efficient, but its evolution remains slow because of its investment cost and amortization. The objectives of the agricultural greenhouse are to create a microclimate that is favorable to the requirements and growth of plants from the surrounding climatic conditions and produce cheap off-season fruits, vegetables and flowers which must be highly available all along the year. The agricultural greenhouse is defined by its structural and functional architecture as well as by the optical, thermal and mechanical qualities of its wall and the accompanying technical support. The greenhouse is supposed to be a confined environment where there is an exchange of several components. The main intervening factors are: light, temperature and relative humidity. When protected, the culture heats up more than when in free air because of the wall that acts as a barrier to harmful influences of the wind and the surrounding climatic variations as well as to the reduction in internal air convection. This thermal evolution state depends on the air-tightness degree of the cover and its physical characteristics. It has to be transparent to solar rays, and must as well absorb and reflect infrared rays emitted by the soil. This leads to trapped solar rays, called the "greenhouse effect". In this article, we propose the dynamic modeling of the greenhouse system, the characterization and analysis of the thermal behavior of the wall for both experimental greenhouses, where the first one is made of polyethylene (tunnel greenhouse) and the second of glass (chapel-shaped greenhouse), throughout experimentation and simulation which finally lead to identifying the evolution in the

  9. Derivation of soil thresholds for lead applying species sensitivity distribution: A case study for root vegetables.

    PubMed

    Ding, Changfeng; Ma, Yibing; Li, Xiaogang; Zhang, Taolin; Wang, Xingxiang

    2016-02-13

    The combination of food quality standard and soil-plant transfer models can be used to derive critical limits of heavy metals for agricultural soils. In this paper, a robust methodology is presented, taking the variations of plant species and cultivars and soil properties into account to derive soil thresholds for lead (Pb) applying species sensitivity distribution (SSD). Three species of root vegetables (four cultivars each for radish, carrot, and potato) were selected to investigate their sensitivity differences for accumulating Pb through greenhouse experiment. Empirical soil-plant transfer model was developed from carrot New Kuroda grown in twenty-one soils covering a wide variation in physicochemical properties and was used to normalize the bioaccumulation data of non-model cultivars. The relationship was then validated to be reliable and would not cause over-protection using data from field experimental sites and published independent studies. The added hazardous concentration for protecting 95% of the cultivars not exceeding the food quality standard (HC5add) were then calculated from the Burr Type III function fitted SSD curves. The derived soil Pb thresholds based on the added risk approach (total soil concentration subtracting the natural background part) were presented as continuous or scenario criteria depending on the combination of soil pH and CEC. Copyright © 2015 Elsevier B.V. All rights reserved.

  10. Uptake and distribution of bisphenol A and nonylphenol in vegetable crops irrigated with reclaimed water.

    PubMed

    Lu, Jian; Wu, Jun; Stoffella, Peter J; Wilson, P Chris

    2015-01-01

    The potential uptake and distribution of bisphenol A (BPA) and nonylphenol (NP) (from reclaimed irrigation water) in edible crops was investigated. BPA and NP were spiked into simulated reclaimed water at environmentally relevant concentrations. Two crops (lettuce, Lactuca sativa and tomato, Lycopersicon esculentum) were grown hydroponically in a greenhouse using the spiked irrigation water under two irrigation exposure scenarios (overhead foliar exposure and subsurface root exposure). BPA concentrations in tomato fruit were 26.6 ± 5.8 (root exposure) and 18.3 ± 3.5 (foliar exposure) μg kg(-1), while concentrations in lettuce leaves were 80.6 ± 23.1 (root exposure) and 128.9 ± 17.4 (foliar exposure) μg kg(-1). NP concentrations in tomato fruit were 46.1 ± 6.6 (root exposure) and 24.6 ± 6.4 (foliar exposure) μg kg(-1), while concentrations in lettuce leaves were 144.1 ± 9.2 (root exposure) and 195.0 ± 16.9 (foliar exposure) μg kg(-1). BPA was relatively mobile in lettuce plants regardless of exposure route. Limited mobility was observed for NP in both crops and BPA in tomatoes. The estimated daily intake of BPA and NP through consumption of vegetables irrigated with reclaimed water ranged from 8.9-62.9 to 11.9-95.1 μg, respectively, depending on the exposure route.

  11. Field and vegetable crops as hosts of larval western spotted cucumber beetle (Coleoptera: Chrysomelidae).

    PubMed

    Pedersen, Andrew B; Godfrey, Larry D

    2011-06-01

    The western spotted cucumber beetle, Diabrotica undecimpunctata undecimpunctata Mannerheim, is an important pest of melons (Cucurmis melo L.) in northern California. Recent observations indicate that adults are using alfalfa (Medicago sativa L.) as a feeding host and larvae may be developing on the roots. Greenhouse studies were conducted during the winters of 2009 and 2010 in which larval development was compared on the roots of six field and vegetable crops commonly grown in the southern Sacramento Valley. The growth parameters used to evaluate the hosts were larval and pupal head capsule width, body width, and body length as well as total survival percentage and survival percentage to the third instar. According to larval growth and survivorship in 2009, maize (Zea mays L.) was the best host, followed by alfalfa and tomato (Solanum lycopersicum L.) that were roughly equivalent to one another. Melon was a slightly weaker host than alfalfa and tomato; sunflower (Helianthus annuus L.) was a completely incompatible host and thus dropped from the 2010 study. In 2010, melon was the weakest host for larval development. Maize was the superior host again followed closely by alfalfa that performed slightly better than tomato and lima bean (Phaseolus lunatus L.). Data suggest that larval western spotted cucumber beetles may primarily develop outside of melon fields and the adults emigrate to melons.

  12. A Hiatus of the Greenhouse Effect

    PubMed Central

    Song, Jinjie; Wang, Yuan; Tang, Jianping

    2016-01-01

    The rate at which the global average surface temperature is increasing has slowed down since the end of the last century. This study investigates whether this warming hiatus results from a change in the well-known greenhouse effect. Using long-term, reliable, and consistent observational data from the Earth’s surface and the top of the atmosphere (TOA), two monthly gridded atmospheric and surface greenhouse effect parameters (Ga and Gs) are estimated to represent the radiative warming effects of the atmosphere and the surface in the infrared range from 1979 to 2014. The atmospheric and surface greenhouse effect over the tropical monsoon-prone regions is found to contribute substantially to the global total. Furthermore, the downward tendency of cloud activity leads to a greenhouse effect hiatus after the early 1990 s, prior to the warming pause. Additionally, this pause in the greenhouse effect is mostly caused by the high number of La Niña events between 1991 and 2014. A strong La Niña indicates suppressed convection in the tropical central Pacific that reduces atmospheric water vapor content and cloud volume. This significantly weakened regional greenhouse effect offsets the enhanced warming influence in other places and decelerates the rising global greenhouse effect. This work suggests that the greenhouse effect hiatus can be served as an additional factor to cause the recent global warming slowdown. PMID:27616203

  13. A Hiatus of the Greenhouse Effect

    NASA Astrophysics Data System (ADS)

    Song, Jinjie; Wang, Yuan; Tang, Jianping

    2016-09-01

    The rate at which the global average surface temperature is increasing has slowed down since the end of the last century. This study investigates whether this warming hiatus results from a change in the well-known greenhouse effect. Using long-term, reliable, and consistent observational data from the Earth’s surface and the top of the atmosphere (TOA), two monthly gridded atmospheric and surface greenhouse effect parameters (Ga and Gs) are estimated to represent the radiative warming effects of the atmosphere and the surface in the infrared range from 1979 to 2014. The atmospheric and surface greenhouse effect over the tropical monsoon-prone regions is found to contribute substantially to the global total. Furthermore, the downward tendency of cloud activity leads to a greenhouse effect hiatus after the early 1990 s, prior to the warming pause. Additionally, this pause in the greenhouse effect is mostly caused by the high number of La Niña events between 1991 and 2014. A strong La Niña indicates suppressed convection in the tropical central Pacific that reduces atmospheric water vapor content and cloud volume. This significantly weakened regional greenhouse effect offsets the enhanced warming influence in other places and decelerates the rising global greenhouse effect. This work suggests that the greenhouse effect hiatus can be served as an additional factor to cause the recent global warming slowdown.

  14. Using a wood stove to heat greenhouses

    Treesearch

    Gloria Whitefeather-Spears

    2009-01-01

    The Red Lake Tribal Forestry Greenhouse in Red Lake, MN, utilizes four types of outdoor furnaces for heating through the fall, winter, and spring. The WoodMaster® is a highly efficient, wood-fired furnace that provides forced-air heat to the greenhouse. The HeatmorTM furnace is an economical wood-fired alternative that can provide lower...

  15. Solar Greenhouses and Sunspaces: Lessons Learned.

    ERIC Educational Resources Information Center

    Thomas, Stephen G.; And Others

    Solar technology systems are being studied, managed, built and offered as an effective alternative energy option. This publication presents background material for the building and operation of better sunspaces and greenhouses. Recent developments in solar technology are explained and information on solar greenhouse and sunspace is provided (in…

  16. Can we delay a greenhouse warming

    SciTech Connect

    Perry, A.M.

    1983-01-01

    The author comments on the EPA report dated September 1983 Can We Delay A Greenhouse Warming. He takes exception to the widely-held interpretation that the answer is not much. The contribution of other greenhouse gases such as methane and nitrous oxide to the EPA scenarios is pointed out, and the lack of understanding of their role is emphasised. (ACR)

  17. A Hiatus of the Greenhouse Effect.

    PubMed

    Song, Jinjie; Wang, Yuan; Tang, Jianping

    2016-09-12

    The rate at which the global average surface temperature is increasing has slowed down since the end of the last century. This study investigates whether this warming hiatus results from a change in the well-known greenhouse effect. Using long-term, reliable, and consistent observational data from the Earth's surface and the top of the atmosphere (TOA), two monthly gridded atmospheric and surface greenhouse effect parameters (Ga and Gs) are estimated to represent the radiative warming effects of the atmosphere and the surface in the infrared range from 1979 to 2014. The atmospheric and surface greenhouse effect over the tropical monsoon-prone regions is found to contribute substantially to the global total. Furthermore, the downward tendency of cloud activity leads to a greenhouse effect hiatus after the early 1990 s, prior to the warming pause. Additionally, this pause in the greenhouse effect is mostly caused by the high number of La Niña events between 1991 and 2014. A strong La Niña indicates suppressed convection in the tropical central Pacific that reduces atmospheric water vapor content and cloud volume. This significantly weakened regional greenhouse effect offsets the enhanced warming influence in other places and decelerates the rising global greenhouse effect. This work suggests that the greenhouse effect hiatus can be served as an additional factor to cause the recent global warming slowdown.

  18. Contents of fluorides in vegetables from areas contaminated by industrial emissions: a preliminary report

    SciTech Connect

    Machoy, Z.; Samujlo, D.

    1981-01-01

    In vegetables grown in 1978 and 1979 near a chemical plant where phosphorites and apatites are processed, according to preliminary data, fluoride was significantly elevated in roots of carrots and parsley and in the leaves of parsley.

  19. Titan's greenhouse and antigreenhouse effects

    NASA Technical Reports Server (NTRS)

    Mckay, Christopher P.; Pollack, James B.; Courtin, Regis

    1992-01-01

    Thermal mechanisms active in Titan's atmosphere are discussed in a brief review of data obtained during the Voyager I flyby in 1980. Particular attention is given to the greenhouse effect (GHE) produced by atmospheric H2, N2, and CH4; this GHE is stronger than that on earth, with CH4 and H2 playing roles similar to those of H2O and CO2 on earth. Also active on Titan is an antigreenhouse effect, in which dark-brown and orange organic aerosols block incoming solar light while allowing IR radiation from the Titan surface to escape. The combination of GHE and anti-GHE leads to a surface temperature about 12 C higher than it would be if Titan had no atmosphere.

  20. Evaluation of primary and secondary treated and disinfected wastewater irrigation of tomato and cucumber plants under greenhouse conditions, regarding growth and safety considerations.

    PubMed

    Manios, T; Papagrigoriou, I; Daskalakis, G; Sabathianakis, I; Terzakis, S; Maniadakis, K; Markakis, G

    2006-08-01

    Tomato and cucumber seedlings were distributed into 10 groups (five for each plant) of 15 plants each. The plants were irrigated for 10 weeks with primary treated wastewater (group A), secondary treated wastewater (group B), chlorinated secondary treated wastewater (group C), a fertilizer dilution (group F), and tap water (group M). All precautions were taken to secure that there was no direct contact between the wastewater and the edible portions of the crops. During this period and on a weekly basis, the height and number of leaves was monitored, while, at the end, the dry weight of leaves, stems, and roots for each plant of each group was measured. Based on these growth parameters, both types of plant in groups A and F recorded the most significant development compared to the other three groups. The plants irrigated with tap water recorded the smallest development, in every case. Plants in groups B and C were similar, with a slight (but not significant) superiority for the plants irrigated with secondary treated wastewater, probably as a result of some phytotoxic effects of residual chloride in the chlorinated wastewater. The presence of nutrients and specifically nitrogen in the various solutions explains the differences satisfactorily. The vegetables grown on the plants of each group were harvested, and their surface tissue analyzed for total coliforms (TC) and enterococci (EC). Tomatoes grown on the plants of groups A and B recorded the highest values for TC, with 505 and 490 cfu/g, respectively, whereas, for cucumbers, those values were 342 and 450 cfu/g, respectively. Enterococci were detected on the surface of harvested vegetables from groups A and B, but the small number of cases and their random character cannot support any strong relations between the used wastewater and their presence. The TC values in group C were very low, far lower than those if group F. No EC were found in either group C or group F. These primary results suggested that irrigation

  1. Greenhouse gases and agriculture. Book chapter

    SciTech Connect

    Jackson, R.B.

    1993-01-01

    Agriculture ranks third in its contribution to Earth's anthropogenically enhanced greenhouse effect. (Energy use and production and chlorofluorocarbons are ranked first and second, respectively.) Specifically, greenhouse gas sources and sinks are increased, and sinks are decreased, by conversion of land to agricultural use, using fertilizers, cultivating paddy rice, producing other plant and animal crops, and by creating and managing animal and plant wastes. However, some of these same activities increase greenhouse gas sinks and decrease greenhouse gas sources so the net effects are not obvious. The paper identifies the agricultural inputs, outputs, and wastes that alter atmospheric concentrations of carbon dioxide, methane, and nitrous oxides, and discusses agriculture's net impact on greenhouse gas fluxes.

  2. Where do California's greenhouse gases come from?

    ScienceCinema

    Fischer, Marc

    2016-07-12

    Last March, more than two years after California passed legislation to slash greenhouse gas emissions 25 percent by 2020, Lawrence Berkeley National Laboratory scientist Marc Fischer boarded a Cessna loaded with air monitoring equipment and crisscrossed the skies above Sacramento and the Bay Area. Instruments aboard the aircraft measured a cocktail of greenhouse gases: carbon dioxide from fossil fuel use, methane from livestock and landfills, CO2 from refineries and power plants, traces of nitrous oxide from agriculture and fuel use, and industrially produced other gases like refrigerants. The flight was part of the Airborne Greenhouse Gas Emissions Survey, a collaboration between Berkeley Lab, the National Oceanic and Atmospheric Administration, and the University of California, and UC Davis to pinpoint the sources of greenhouse gases in central California. The survey is intended to improve inventories of the states greenhouse gas emissions, which in turn will help scientists verify the emission reductions mandated by AB-32, the legislation enacted by California in 2006.

  3. Prevalence of antibiotic resistance genes and bacterial pathogens in long-term manured greenhouse soils as revealed by metagenomic survey.

    PubMed

    Fang, Hua; Wang, Huifang; Cai, Lin; Yu, Yunlong

    2015-01-20

    Antibiotic resistance genes (ARGs), human pathogenic bacteria (HPB), and HPB carrying ARGs pose a high risk to soil ecology and public health. Here, we used a metagenomic approach to investigate their diversity and abundance in chicken manures and greenhouse soils collected from Guli, Pulangke, and Hushu vegetable bases with different greenhouse planting years in Nanjing, Eastern China. There was a positive correlation between the levels of antibiotics, ARGs, HPB, and HPB carrying ARGs in manures and greenhouse soils. In total, 156.2–5001.4 μg/kg of antibiotic residues, 22 classes of ARGs, 32 HPB species, and 46 species of HPB carrying ARGs were found. The highest relative abundance was tetracycline resistance genes (manures) and multidrug resistance genes (greenhouse soils). The dominant HPB and HPB carrying ARGs in the manures were Bacillus anthracis, Bordetella pertussis, and B. anthracis (sulfonamide resistance gene, sul1), respectively. The corresponding findings in greenhouse soils were Mycobacterium tuberculosis and M. ulcerans, M. tuberculosis (macrolide-lincosamide-streptogramin resistance protein, MLSRP), and B. anthracis (sul1), respectively. Our findings confirmed high levels of antibiotics, ARGs, HPB, and HPB carrying ARGs in the manured greenhouse soils compared with those in the field soils, and their relative abundance increased with the extension of greenhouse planting years.

  4. Factors affecting vegetable growers' exposure to fungal bioaerosols and airborne dust.

    PubMed

    Hansen, Vinni M; Meyling, Nicolai Vitt; Winding, Anne; Eilenberg, Jørgen; Madsen, Anne Mette

    2012-03-01

    We have quantified vegetable growers' exposure to fungal bioaerosol components including (1→3)-β-d-glucan (β-glucan), total fungal spores, and culturable fungal units. Furthermore, we have evaluated factors that might affect vegetable growers' exposure to fungal bioaerosols and airborne dust. Investigated environments included greenhouses producing cucumbers and tomatoes, open fields producing cabbage, broccoli, and celery, and packing facilities. Measurements were performed at different times during the growth season and during execution of different work tasks. Bioaerosols were collected with personal and stationary filter samplers. Selected fungal species (Beauveria spp., Trichoderma spp., Penicillium olsonii, and Penicillium brevicompactum) were identified using different polymerase chain reaction-based methods and sequencing. We found that the factors (i) work task, (ii) crop, including growth stage of handled plant material, and (iii) open field versus greenhouse significantly affected the workers' exposure to bioaerosols. Packing of vegetables and working in open fields caused significantly lower exposure to bioaerosols, e.g. mesophilic fungi and dust, than harvesting in greenhouses and clearing of senescent greenhouse plants. Also removing strings in cucumber greenhouses caused a lower exposure to bioaerosols than harvest of cucumbers while removal of old plants caused the highest exposure. In general, the exposure was higher in greenhouses than in open fields. The exposures to β-glucan during harvest and clearing of senescent greenhouse plants were very high (median values ranging between 50 and 1500 ng m(-3)) compared to exposures reported from other occupational environments. In conclusion, vegetable growers' exposure to bioaerosols was related to the environment, in which they worked, the investigated work tasks, and the vegetable crop.

  5. 13. Greenhouse, east elevation. The boardandbatten wall covers an opening ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    13. Greenhouse, east elevation. The board-and-batten wall covers an opening that was originally fitted with windows which allowed sunlight into the greenhouse. - John Bartram House & Garden, Greenhouse, 54th Street & LIndbergh Boulevard, Philadelphia, Philadelphia County, PA

  6. Soil genotoxicity induced by successive applications of chlorothalonil under greenhouse conditions.

    PubMed

    Jin, Xiangxiang; Cui, Ning; Zhou, Wei; Khorram, Mahdi Safaei; Wang, Donghong; Yu, Yunlong

    2014-05-01

    Greenhouse production of vegetables has been developed rapidly in China. High temperature and humidity inside the greenhouse make this environment more suitable for fast reproduction of fungal diseases. Fungicides are among the chemicals used extensively in the greenhouse to prevent crops from invasive infections by phytopathogens; however, little is known about the accumulation of fungicides in soil and their effect on soil quality under greenhouse conditions. In the present study, the accumulation of the fungicide chlorothalonil (CT) and its toxic metabolite hydroxy-chlorothalonil (HCT) in soil as well as their related soil genotoxicity under greenhouse conditions was investigated. The results indicated that both CT and HCT accumulated in soil with repeated applications of CT, and the accumulation level was strongly correlated to application dosage and its frequency. In addition, soil genotoxicity, which was measured by Vicia faba, also increased with the accumulation of CT and HCT, and the main contributor to this phenomenon was CT rather than HCT. The data demonstrated that successive applications of fungicides may result in their accumulation in soil and thus a decline in soil quality. © 2014 SETAC.

  7. Cavity size and copper root pruning affect production and establishment of container-grown longleaf pine seedlings

    Treesearch

    Marry Anne Sword Sayer; James D. Haywood; Shi-Jean Susana. Sung

    2009-01-01

    With six container types, we tested the effects of cavity size (i.e., 60, 93, and 170 ml) and copper root pruning on the root system development of longleaf pine (Pinus palustris Mill.) seedlings grown in a greenhouse. We then evaluated root egress during a root growth potential test and assessed seedling morphology and root system development 1 year after planting in...

  8. Effects of Phosphorus on Morphology and Foliar Nutrient Concentrations of Hydroponically Grown Scaevola aemula R. Br. ‘Whirlwind Blue’

    USDA-ARS?s Scientific Manuscript database

    In commercial greenhouses, fan flower ‘Whirlwind Blue’ (Scaevola aemula R. Br.) plants appear sensitive to phosphorus rates typically applied to other floricultural crops. In order to quantify this response, fan flower plants were grown in Hoagland solutions containing 0, 20, 40, 60, or 80 mg P/L. ...

  9. Thermodynamics of greenhouse systems for the northern latitudes: analysis, evaluation and prospects for primary energy saving.

    PubMed

    Bronchart, Filip; De Paepe, Michel; Dewulf, Jo; Schrevens, Eddie; Demeyer, Peter

    2013-04-15

    In Flanders and the Netherlands greenhouse production systems produce economically important quantities of vegetables, fruit and ornamentals. Indoor environmental control has resulted in high primary energy use. Until now, the research on saving primary energy in greenhouse systems has been mainly based on analysis of energy balances. However, according to the thermodynamic theory, an analysis based on the concept of exergy (free energy) and energy can result in new insights and primary energy savings. Therefore in this paper, we analyse the exergy and energy of various processes, inputs and outputs of a general greenhouse system. Also a total system analysis is then performed by linking the exergy analysis with a dynamic greenhouse climate growth simulation model. The exergy analysis indicates that some processes ("Sources") lie at the origin of several other processes, both destroying the exergy of primary energy inputs. The exergy destruction of these Sources is caused primarily by heat and vapour loss. Their impact can be compensated by exergy input from heating, solar radiation, or both. If the exergy destruction of these Sources is reduced, the necessary compensation can also be reduced. This can be accomplished through insulating the greenhouse and making the building more airtight. Other necessary Sources, namely transpiration and loss of CO2, have a low exergy destruction compared to the other Sources. They are therefore the best candidate for "pump" technologies ("vapour heat pump" and "CO2 pump") designed to have a low primary energy use. The combination of these proposed technologies results in an exergy efficient greenhouse with the highest primary energy savings. It can be concluded that exergy analyses add additional information compared to only energy analyses and it supports the development of primary energy efficient greenhouse systems.

  10. Energy education through a demonstration urban greenhouse retrofit. Final report

    SciTech Connect

    Gilcrest, M.J.

    1981-01-01

    Construction of this passive solar retrofit in the City of Baltimore, MD began in November of 1979 and was completed in September 1980. Construction entailed the adding of a second story masonry room with 120 ft/sup 2/ of south facing glazing to an existing row home. The purpose of the structure was to add heat as well as vegetables to the home. The addition's first heating season was 1980-1981. A hydroponic gardening system was established in September 1980. Open houses were held in the Spring of 1981 to share the experience with area residents. With the insulation and windows (not provided under this grant, but by owners) and the greenhouse addition (which is the subject of this grant), the gallons of fuel oil used for heating was reduced by 47%.

  11. Integrating terrestrial sequestration into a greenhouse gas management plan

    NASA Astrophysics Data System (ADS)

    Brown, Joel R.; Sampson, Neil

    Terrestrial sequestration has the potential to contribute to national and global greenhouse gas management strategies. However, spatial and temporal variability in sequestration potential and in the implementation of sequestering technologies introduces serious questions about how to resolve uncertainties and raise the credibility of terrestrial sequestration. Carbon flux in terrestrial ecosystems without land use change generally is less than one ton CO2e/ha and driven primarily by precipitation. Land use and management changes are relatively common and are driven by economics and social considerations both in the private and public sectors. Implementing a credible greenhouse gas management program that integrates terrestrial sequestration along with other sources and sinks requires a systematic approach to identify and quantitatively monitor changes in the drivers of terrestrial sequestration. A credible terrestrial sequestration monitoring program will require close attention to integrating direct measurement of soils and vegetation, statistically valid scaling, remote sensing, and computer modeling. Predicting changes at a level of confidence useful to policy development will also require an understanding of how land owners and managers respond to private sector price signals and government conservation initiatives.

  12. Advancing agricultural greenhouse gas quantification*

    NASA Astrophysics Data System (ADS)

    Olander, Lydia; Wollenberg, Eva; Tubiello, Francesco; Herold, Martin

    2013-03-01

    1. Introduction Better information on greenhouse gas (GHG) emissions and mitigation potential in the agricultural sector is necessary to manage these emissions and identify responses that are consistent with the food security and economic development priorities of countries. Critical activity data (what crops or livestock are managed in what way) are poor or lacking for many agricultural systems, especially in developing countries. In addition, the currently available methods for quantifying emissions and mitigation are often too expensive or complex or not sufficiently user friendly for widespread use. The purpose of this focus issue is to capture the state of the art in quantifying greenhouse gases from agricultural systems, with the goal of better understanding our current capabilities and near-term potential for improvement, with particular attention to quantification issues relevant to smallholders in developing countries. This work is timely in light of international discussions and negotiations around how agriculture should be included in efforts to reduce and adapt to climate change impacts, and considering that significant climate financing to developing countries in post-2012 agreements may be linked to their increased ability to identify and report GHG emissions (Murphy et al 2010, CCAFS 2011, FAO 2011). 2. Agriculture and climate change mitigation The main agricultural GHGs—methane and nitrous oxide—account for 10%-12% of anthropogenic emissions globally (Smith et al 2008), or around 50% and 60% of total anthropogenic methane and nitrous oxide emissions, respectively, in 2005. Net carbon dioxide fluxes between agricultural land and the atmosphere linked to food production are relatively small, although significant carbon emissions are associated with degradation of organic soils for plantations in tropical regions (Smith et al 2007, FAO 2012). Population growth and shifts in dietary patterns toward more meat and dairy consumption will lead to

  13. Fruits and vegetables (image)

    MedlinePlus

    A healthy diet includes adding vegetables and fruit every day. Vegetables like broccoli, green beans, leafy greens, zucchini, cauliflower, cabbage, carrots, and tomatoes are low in calories and high in fiber, ...

  14. Greenhouse gas mitigation options for Washington State

    SciTech Connect

    Garcia, N.

    1996-04-01

    President Clinton, in 1993, established a goal for the United States to return emissions of greenhouse gases to 1990 levels by the year 2000. One effort established to help meet this goal was a three part Environmental Protection Agency state grant program. Washington State completed part one of this program with the release of the 1990 greenhouse gas emissions inventory and 2010 projected inventory. This document completes part two by detailing alternative greenhouse gas mitigation options. In part three of the program EPA, working in partnership with the States, may help fund innovative greenhouse gas reduction strategies. The greenhouse gas control options analyzed in this report have a wide range of greenhouse gas reductions, costs, and implementation requirements. In order to select and implement a prudent mix of control strategies, policy makers need to have some notion of the potential change in climate, the consequences of that change and the uncertainties contained therein. By understanding the risks of climate change, policy makers can better balance the use of scarce public resources for concerns that are immediate and present against those that affect future generations. Therefore, prior to analyzing alternative greenhouse gas control measures, this report briefly describes the phenomenon and uncertainties of global climate change, and then projects the likely consequences for Washington state.

  15. Scientists' internal models of the greenhouse effect

    NASA Astrophysics Data System (ADS)

    Libarkin, J. C.; Miller, H.; Thomas, S. R.

    2013-12-01

    A prior study utilized exploratory factor analysis to identify models underlying drawings of the greenhouse effect made by entering university freshmen. This analysis identified four archetype models of the greenhouse effect that appear within the college enrolling population. The current study collected drawings made by 144 geoscientists, from undergraduate geoscience majors through professionals. These participants scored highly on a standardized assessment of climate change understanding and expressed confidence in their understanding; many also indicated that they teach climate change in their courses. Although geoscientists held slightly more sophisticated greenhouse effect models than entering freshmen, very few held complete, explanatory models. As with freshmen, many scientists (44%) depict greenhouse gases in a layer in the atmosphere; 52% of participants depicted this or another layer as a physical barrier to escaping energy. In addition, 32% of participants indicated that incoming light from the Sun remains unchanged at Earth's surface, in alignment with a common model held by students. Finally, 3-20% of scientists depicted physical greenhouses, ozone, or holes in the atmosphere, all of which correspond to non-explanatory models commonly seen within students and represented in popular literature. For many scientists, incomplete models of the greenhouse effect are clearly enough to allow for reasoning about climate change. These data suggest that: 1) better representations about interdisciplinary concepts, such as the greenhouse effect, are needed for both scientist and public understanding; and 2) the scientific community needs to carefully consider how much understanding of a model is needed before necessary reasoning can occur.

  16. An integrated control of Pythium root rot of greenhouse tomato.

    PubMed

    Tu, J C

    2002-01-01

    Pythium root rot caused by Pythium aphanidermatum is one of the most important diseases of greenhouse tomatoes. Hydroponic culture exacerbates the problem. Both nutrient film technique (NFT) and recirculating growing systems pose a challenge in the control of this disease, because the pathogen, especially the zoospores, can spread easily in the recirculating solution to the whole growing system. Fortunately, hydroponically grown plants are easier to manipulate than soil grown plants, proper manipulation of root environments can lead to excellent disease control. This paper reports the development of an effective integrated control measure for pythium root rot of tomato by integrating pH, bioagent, and ultra-violet irradiation in a specific manner. This integrated control consists of three operations: a) before transplanting, the UV system is connected to sterilize the recirculating solution using 100 mJcm-2; b) after transplanting, the nutrient solution is delivered at pH 5.0 regime for five weeks followed by adjusting pH to 5.8 to 6.2 regime for one week; and c) bacterial bioagent, such as Pseudomonas is introduced into the root zone at 100 mL per plant at 10(8) bacteria mL-1 or added to the nutrient solution to arrive at 10(6) bacteria mL-1 in the solution. This report also discusses the advantages and limitations of this measure in the control of pythium root rot.

  17. Arbuscular mycorrhizal fungi (AMF) improved growth and nutritional quality of greenhouse-grown lettuce.

    PubMed

    Baslam, Marouane; Garmendia, Idoia; Goicoechea, Nieves

    2011-05-25

    Lettuce can be associated with arbuscular mycorrhizal fungi (AMF). This symbiosis involves a molecular dialogue between fungus and plant that includes the activation of antioxidant, phenylpropanoid, or carotenoid pathways. The objective of this study was to test if the association of lettuce with AMF benefited plant growth and increased the contents of compounds potentially beneficial for human health. Results showed that AMF improved growth of lettuce, thus producing a dilution effect on the concentrations of some mineral nutrients (e.g., Ca and Mn). However, Cu, Fe, anthocyanins, carotenoids, and, to a lesser extent, phenolics appeared in higher concentrations (on a wet basis) in mycorrhizal than in nonmycorrhizal plants.

  18. Control of downy mildew (Pseudoperonospora cubensis) of greenhouse grown cucumbers with alternative biological agents.

    PubMed

    Scherf, A; Schuster, C; Marx, P; Gärber, U; Konstantinidou-Doltsinis, S; Schmitt, A

    2010-01-01

    In organic cucumber production infection with downy mildew (Pseudoperonospora cubensis) is a major problem. Plant extracts from Glycyrrhiza glabra L. (licorice), a plant belonging to the family Fabaceae, and Salvia officinalis (sage) as well as cultures of the bacterium Aneurinibacillus migulanus were investigated for efficacy of disease control under commercial growing conditions. Contrary to bioassays, where sage extract and the microorganism showed highest activity, in the trials of 2008 G. glabra extract was more effective than sage extract or A. migulanus against P. cubensis. Parameters such as concentrations of the preparations or application intervals could have been the reason for this. In the following year's trial (2009) the concentration of these agents was therefore increased somewhat and plants were either treated in seven day application intervals or in ten day application intervals. In the semi-commercial trials of 2009 all alternative biological agents showed good efficacies up to around 80% against infection with downy mildew. The application interval seemed to have a marginal effect only. Again, the licorice extract tended to be the best agent.

  19. Antioxidant capacity and antimutagenic activity of natural oleoresin from greenhouse grown tomatoes (Lycopersicon esculentum).

    PubMed

    Rodríguez-Muñoz, Eustolia; Herrera-Ruiz, Gilberto; Pedraza-Aboytes, Gustavo; Loarca-Piña, Guadalupe

    2009-03-01

    Natural oleoresins rich in lycopene were obtained from two varieties of tomato (Zedona and Gironda) and their nutraceutical potential (antioxidant and antimutagenic capacity) was evaluated. Both oleoresins had a high content of lycopene, 58.33+/-1.67 mg/g (Zedona) and 63.97+/-0.80 mg/g (Gironda). The antioxidant activity (AA) of the oleoresins by beta-carotene method were 56.4-74.5% (Zedona) and 51-72.8% (Gironda), while when using the free radical stable 2,2-diphenyl-picryl-hydrazyl (DPPH) method, the antiradical activity (ARA) was determined to be 18.2-32.7% (Zedona) and 16.6-26.7% (Gironda) for the concentrations tested that of 200-400 microM equivalents of lycopene. The antimutagenic activity of the oleoresins was tested against aflatoxin B1 (AFB1) using the microsuspension assay, both varieties had a very high antimutagenic potential against AFB1 (60-66%).These results suggest the NCRT can be taken advantage to obtaining rich oleoresin in lycopene with a nutraceutical value.

  20. Greenhouse Gas Emission from Corn Rotations and Perennial Grasses in Iowa Grown for Biofuel Production

    USDA-ARS?s Scientific Manuscript database

    The ideal bioenergy crop is characterized by high yield, low energy input, low nutrient requirements, low production cost, and composition with minimal contaminants. Perennial grasses show better efficiency, higher biomass yield, and lower energy input and nutrient requirements than continuous corn ...

  1. Determination of diagnostic standards on saturated soil extracts for cut roses grown in greenhouses

    PubMed Central

    Cabrera, Raúl Iskander

    2017-01-01

    This work comprises the theoretical determination and validation of diagnostic standards for the analysis of saturated soil extracts for cut rose flower crops (Rosa spp.) growing in the Bogota Plateau, Colombia. The data included 684 plant tissue analyses and 684 corresponding analyses of saturated soil extracts, all collected between January 2009 and June 2013. The tissue and soil samples were selected from 13 rose farms, and from cultivars grafted on the 'Natal Briar' rootstock. These concurrent samples of soil and plant tissues represented 251 production units (locations) of approximately 10,000 m2 distributed across the study area. The standards were conceived as a tool to improve the nutritional balance in the leaf tissue of rose plants and thereby define the norms for expressing optimum productive potential relative to nutritional conditions in the soil. To this end, previously determined diagnostic standard for rose leaf tissues were employed to obtain rates of foliar nutritional balance at each analyzed location and as criteria for determining the diagnostic norms for saturated soil extracts. Implementing this methodology to foliar analysis, showed a higher significant correlation for diagnostic indices. A similar behavior was observed in saturated soil extracts analysis, becoming a powerful tool for integrated nutritional diagnosis. Leaf analyses determine the most limiting nutrients for high yield and analyses of saturated soil extracts facilitate the possibility of correcting the fertigation formulations applied to soils or substrates. Recommendations are proposed to improve the balance in soil-plant system with which the possibility of yield increase becomes more probable. The main recommendations to increase and improve rose crop flower yields would be: continuously check pH values of SSE, reduce the amounts of P, Fe, Zn and Cu in fertigation solutions and carefully analyze the situation of Mn in the soil-plant system. PMID:28542547

  2. Determination of diagnostic standards on saturated soil extracts for cut roses grown in greenhouses.

    PubMed

    Franco-Hermida, John Jairo; Quintero, María Fernanda; Cabrera, Raúl Iskander; Guzman, José Miguel

    2017-01-01

    This work comprises the theoretical determination and validation of diagnostic standards for the analysis of saturated soil extracts for cut rose flower crops (Rosa spp.) growing in the Bogota Plateau, Colombia. The data included 684 plant tissue analyses and 684 corresponding analyses of saturated soil extracts, all collected between January 2009 and June 2013. The tissue and soil samples were selected from 13 rose farms, and from cultivars grafted on the 'Natal Briar' rootstock. These concurrent samples of soil and plant tissues represented 251 production units (locations) of approximately 10,000 m2 distributed across the study area. The standards were conceived as a tool to improve the nutritional balance in the leaf tissue of rose plants and thereby define the norms for expressing optimum productive potential relative to nutritional conditions in the soil. To this end, previously determined diagnostic standard for rose leaf tissues were employed to obtain rates of foliar nutritional balance at each analyzed location and as criteria for determining the diagnostic norms for saturated soil extracts. Implementing this methodology to foliar analysis, showed a higher significant correlation for diagnostic indices. A similar behavior was observed in saturated soil extracts analysis, becoming a powerful tool for integrated nutritional diagnosis. Leaf analyses determine the most limiting nutrients for high yield and analyses of saturated soil extracts facilitate the possibility of correcting the fertigation formulations applied to soils or substrates. Recommendations are proposed to improve the balance in soil-plant system with which the possibility of yield increase becomes more probable. The main recommendations to increase and improve rose crop flower yields would be: continuously check pH values of SSE, reduce the amounts of P, Fe, Zn and Cu in fertigation solutions and carefully analyze the situation of Mn in the soil-plant system.

  3. Increased photosynthetic acclimation in alfalfa associated with arbuscular mycorrhizal fungi (AMF) and cultivated in greenhouse under elevated CO2.

    PubMed

    Goicoechea, Nieves; Baslam, Marouane; Erice, Gorka; Irigoyen, Juan José

    2014-11-15

    Medicago sativa L. (alfalfa) can exhibit photosynthetic down-regulation when grown in greenhouse conditions under elevated atmospheric CO2. This forage legume can establish a double symbiosis with nitrogen fixing bacteria and arbuscular mycorrhizal fungi (AMF), which may increase the carbon sink effect of roots. Our aim was to assess whether the association of alfalfa with AMF can avoid, diminish or delay the photosynthetic acclimation observed in previous studies performed with nodulated plants. The results, however, showed that mycorrhizal (M) alfalfa at the end of their vegetative period had lower carbon (C) discrimination than non-mycorrhizal (NM) controls, indicating photosynthetic acclimation under ECO2 in plants associated with AMF. Decreased C discrimination was due to the acclimation of conductance, since the amount of Rubisco and the expression of genes codifying both large and small subunits of Rubisco were similar or slightly higher in M than in NM plants. Moreover, M alfalfa accumulated a greater amount of soluble sugars in leaves than NM plants, thus favoring a down-regulation effect on photosynthetic rates. The enhanced contents of sugars in leaves coincided with a reduced percentage of arbuscules in roots, suggesting decreased sink of carbohydrates from shoots to roots in M plants. The shorter life cycle of alfalfa associated with AMF in comparison with the NM controls may also be related to the accelerated photosynthetic acclimation in M plants. Further research is needed to clarify to what extent this behavior could be extrapolated to alfalfa cultivated in the field and subjected to periodic cutting of shoots under climatic change scenarios. Copyright © 2014 Elsevier GmbH. All rights reserved.

  4. Natural vegetation inventory

    NASA Technical Reports Server (NTRS)

    Schrumpf, B. J.

    1973-01-01

    Unique characteristics of ERTS imagery can be used to inventory natural vegetation. While satellite images can seldom be interpreted and identified directly in terms of vegetation types, such types can be inferred by interpretation of physical terrain features and through an understanding of the ecology of the vegetation.

  5. The greenhouse and antigreenhouse effects on Titan

    NASA Technical Reports Server (NTRS)

    Mckay, Christopher P.; Pollack, James B.; Courtin, Regis

    1991-01-01

    The parallels between the atmospheric thermal structure of the Saturnian satellite Titan and the hypothesized terrestrial greenhouse effect can serve as bases for the evaluation of competing greenhouse theories. Attention is presently drawn to the similarity between the roles of H2 and CH4 on Titan and CO2 and H2O on earth. Titan also has an antigreenhouse effect due to a high-altitude haze layer which absorbs at solar wavelengths, while remaining transparent in the thermal IR; if this haze layer were removed, the antigreenhouse effect would be greatly reduced, exacerbating the greenhouse effect and raising surface temperature by over 20 K.

  6. Greenhouse gas mitigation in agriculture.

    PubMed

    Smith, Pete; Martino, Daniel; Cai, Zucong; Gwary, Daniel; Janzen, Henry; Kumar, Pushpam; McCarl, Bruce; Ogle, Stephen; O'Mara, Frank; Rice, Charles; Scholes, Bob; Sirotenko, Oleg; Howden, Mark; McAllister, Tim; Pan, Genxing; Romanenkov, Vladimir; Schneider, Uwe; Towprayoon, Sirintornthep; Wattenbach, Martin; Smith, Jo

    2008-02-27

    Agricultural lands occupy 37% of the earth's land surface. Agriculture accounts for 52 and 84% of global anthropogenic methane and nitrous oxide emissions. Agricultural soils may also act as a sink or source for CO2, but the net flux is small. Many agricultural practices can potentially mitigate greenhouse gas (GHG) emissions, the most prominent of which are improved cropland and grazing land management and restoration of degraded lands and cultivated organic soils. Lower, but still significant mitigation potential is provided by water and rice management, set-aside, land use change and agroforestry, livestock management and manure management. The global technical mitigation potential from agriculture (excluding fossil fuel offsets from biomass) by 2030, considering all gases, is estimated to be approximately 5500-6000Mt CO2-eq.yr-1, with economic potentials of approximately 1500-1600, 2500-2700 and 4000-4300Mt CO2-eq.yr-1 at carbon prices of up to 20, up to 50 and up to 100 US$ t CO2-eq.-1, respectively. In addition, GHG emissions could be reduced by substitution of fossil fuels for energy production by agricultural feedstocks (e.g. crop residues, dung and dedicated energy crops). The economic mitigation potential of biomass energy from agriculture is estimated to be 640, 2240 and 16 000Mt CO2-eq.yr-1 at 0-20, 0-50 and 0-100 US$ t CO2-eq.-1, respectively.

  7. Greenhouse Trace Gases in Deadwood

    NASA Astrophysics Data System (ADS)

    Covey, Kristofer; Bueno de Mesquita, Cliff; Oberle, Brad; Maynard, Dan; Bettigole, Charles; Crowther, Thomas; Duguid, Marlyse; Steven, Blaire; Zanne, Amy; Lapin, Marc; Ashton, Mark; Oliver, Chad; Lee, Xuhui; Bradford, Mark

    2016-04-01

    Deadwood, long recognized as playing an important role in carbon cycling in forest ecosystems, is more recently drawing attention for its potential role in the cycling of other greenhouse trace gases. We report data from four independent studies measuring internal gas concentrations in deadwood in in three Quercus dominated upland forest systems in the Northeastern and Central United States. Mean methane concentrations in deadwood were 23 times atmospheric levels, indicating a lower bound, mean radial wood surface area flux of ~6 x 10-4 μmol CH4 m-2 s-1. Site, decay class, diameter, and species were all highly significant predictors of methane abundance in deadwood, and log diameter and decay stage interacted as important controls limiting methane concentrations in the smallest and most decayed logs. Nitrous oxide concentrations were negatively correlated with methane and on average ~25% lower than ambient, indicating net consumption of nitrous oxide. These data suggest nonstructural carbohydrates fuel archaeal methanogens and confirm the potential for widespread in situ methanogenesis in both living and deadwood. Applying this understanding to estimate methane emissions from microbial activity in living trees implies a potential global flux of 65.6±12.0 Tg CH4 yr-1, more than 20 times greater than currently considered.

  8. Methane Greenhouses and Anti-Greenhouses During the Archean Era

    NASA Astrophysics Data System (ADS)

    Kasting, J. F.; Pavlov, A. A.

    2002-12-01

    Climate and life are coupled today through the biogeochemical carbon cycle, but they may have been even more tightly coupled in the distant past when atmospheric O2 levels were lower. The finding of mass-independently fractionated S isotopes in Archean rocks confirms that pO2 was very low, probably <10-13 times the present level, prior to 2.3 Ga (1). The Sun was also some 20 percent less luminous at this time (2). High CO2 levels were initially proposed to solve this `faint young Sun problem' (3); however, these levels are in conflict in data from paleosols (4). CH4 is an alternative greenhouse gas which could have kept the Archean climate warm if present at concentrations of 0.01-0.1 percent by volume (5). The primary source of methane is biological. CH4 is produced by methanogenic bacteria that today live in anaerobic environments such as the intestines of ruminants and the water-logged soils underlying rice paddies. During the Archean, however, methanogens should have been widespread, and the methane they produced would have had a long photochemical lifetimes, around 10,000 years (6). Most methanogens are thermophiles or hyperthermophiles, and those which are more thermophilic have shorter doubling times than those that prefer cooler temperatures. This suggests that a positive feedback loop may have existed, whereby methanogens warmed the climate by releasing CH4, which in turn promoted the proliferation of faster-growing methanogens. This positive feedback would have been halted, however, once the ratio of CH4 to CO2 in the atmosphere exceeded unity. At this point, polymerization of CH4 by solar UV radiation would have caused the formation of an organic haze layer similar to that observed today on Titan. Such a haze layer would have cooled the climate by creating an `anti-greenhouse effect.' This creates an overall negative feedback loop that may have been responsible for maintaining a stable Archean climate. The rise of O2 at 2.3 Ga disrupted this equilibrium

  9. [Low risk of reproductive disorders among female greenhouse workers--safe work conditions or health selection for the light work?].

    PubMed

    Jurewicz, Joanna; Hanke, Wojciech; Makowiec-Dabrowska, Teresa

    2008-01-01

    There are two major potential hazards typical of work in greenhouses: hard physical work or exposure to pesticides. The aim of the study was to investigate whether the work in greenhouse during pregnancy have an adverse effect on its outcome (preterm delivery, spontaneous abortion and birth defects). The study was performed in a group of 460 women employed in 14 greenhouses involved in growing vegetables and flowers. The rate of spontaneous abortions was much elbeit insignificantly higher in the women working in greenhouses during pregnancy than in those employed out of them; that applied mostly to the women performing light jobs in greenhouses. An increased risk of preterm delivery and spontaneous abortion was also observed in women performing greenhouse light jobs. No significantly increased risk of birth defects was observed in children born to women working in greenhouses. Neither was there any relationship between exposure to RD or ED pesticides exposure--and the occurrence of preterm delivery, spontaneous abortion and birth defects. No higher risk of pathological pregnancy that could be associated with hard physical work and pesticide exposure was observed. This may result from the fact that women themselves select an appropriate kind of job during pregnancy and a possible removal of women with pathological pregnancy from jobs involving pesticide exposure, as well as from the promotion of biological protection. The greenhouse workers should be aware of the two typical hazards found in greenhouses (hard work and exposure to pesticides) and their potential negative effects on the reproduction. The results of this study warrant the need for further study of the effect of pesticide exposure and work load on the pregnancy outcome.

  10. Vegetable oil fuel standards

    SciTech Connect

    Pryde, E.H.

    1982-01-01

    Suggested standards for vegetable oils and ester fuels, as well as ASTM specifications for No. 2 diesel oil are given. The following physical properties were discussed: cetane number, cloud point, distillation temperatures, flash point, pour point, turbidity, viscosity, free fatty acids, iodine value, phosphorus, and wax. It was apparent that vegetable oils and their esters cannot meet ASTM specifications D975 for No. 2 diesel oil for use in the diesel engine. Vegetable oil modification or engine design modification may make it possible eventually for vegetable oils to become suitable alternative fuels. Vegetable oils must be recognized as experimental fuels until modifications have been tested thoroughly and generally accepted. 1 table. (DP)

  11. Performance of an energy conserving greenhouse with solar heated plant-root-soil

    SciTech Connect

    Dale, A.C.; Hammer, P.A.

    1983-06-01

    This project was initiated in October 1980 with the goal of the development of an energy efficient greenhouse with a south front solar energy collector which, when combined with an active air fluid solar heat collector for heating the plant soil, would reduce the need for fossil fuels by about 85 percent. The experimental greenhouse selected is 7.32 m wide by 10.97 long. It has a single-sloped roof with a 4.88 m high south front and a 2.44 m high north wall. It also has a permanently insulated north wall, a removable insulated ceiling, and openable and closeable insulating curtains (drapes) over the south, east and west walls. Three crops of tomatoes were grown in the greenhouse. In the first trial in 1981-1982, a too low minimum ambient temperature was selected for supplementary heat to be added, thus tomato production was low. In the second crop in 1982 Cultivar-Tropic tomatoes were grown and production was excellent exceeding normal production for the period in which the tomatoes were harvested. Production in the fall of 1982 with Cultivar-Dombito tomatoes was low with yields about one-half as good as the spring, 1982 production. Supplementary energy requirements were low with solar energy supplying about 45 percent of all heat required for all crops.

  12. Economic aspects of mycotoxins in fruits and vegetables

    USDA-ARS?s Scientific Manuscript database

    International trade in fresh fruit and vegetables has grown greatly in the past twenty years, and is presently a multi-billion dollar business representing the major export for many developing countries. There has been a global effort to develop and implement safe food handling for the entire food ...

  13. Relations between red alder composition and understory vegetation in young mixed forests of southeast Alaska.

    Treesearch

    Thomas A. Hanley; Robert L. Deal; Ewa H. Orlikowska

    2006-01-01

    Interest in mixed red alder (Alnus rubra Bong.)—conifer young-growth stands has grown in southeast Alaska, USA, because they appear to provide much more productive understory vegetation and wildlife habitat than do similar-aged pure conifer stands. We studied understory vegetation in nine even-aged young-growth stands (38-42 years old)...

  14. Voluntary reporting of greenhouse gases, 1995

    SciTech Connect

    1996-07-01

    The Voluntary Reporting Program for greenhouse gases is part of an attempt by the U.S. Government to develop innovative, low-cost, and nonregulatory approaches to limit emissions of greenhouse gases. It is one element in an array of such programs introduced in recent years as part of the effort being made by the United States to comply with its national commitment to stabilize emissions of greenhouse gases under the Framework Convention on Climate Change. The Voluntary Reporting Program, developed pursuant to Section 1605(b) of the Energy Policy Act of 1992, permits corporations, government agencies, households, and voluntary organizations to report to the Energy Information Administration (EIA) on actions taken that have reduced or avoided emissions of greenhouse gases.

  15. Multiagency Initiative to Provide Greenhouse Gas Information

    NASA Astrophysics Data System (ADS)

    Boland, Stacey W.; Duren, Riley M.

    2009-11-01

    Global Greenhouse Gas Information System Workshop; Albuquerque, New Mexico, 20-22 May 2009; The second Greenhouse Gas Information System (GHGIS) workshop brought together 74 representatives from 28 organizations including U.S. government agencies, national laboratories, and members of the academic community to address issues related to the understanding, operational monitoring, and tracking of greenhouse gas emissions and carbon offsets. The workshop was held at Sandia National Laboratories and organized by an interagency collaboration among NASA centers, Department of Energy laboratories, and the U.S. National Oceanic and Atmospheric Administration. It was motivated by the perceived need for an integrated interagency, community-wide initiative to provide information about greenhouse gas sources and sinks at policy-relevant temporal and spatial scales. Such an initiative could significantly enhance the ability of national and regional governments, industry, and private citizens to implement and evaluate effective climate change mitigation policies.

  16. The Greenhouse Effect in a Vial.

    ERIC Educational Resources Information Center

    Golden, Richard; Sneider, Cary

    1989-01-01

    Presents an example of a greenhouse-effect experiment from the Climate Protection Institute. Analyzes the amount of carbon dioxide in ambient air, human exhalation, automobile exhaust, and nearly pure carbon dioxide by titrating with ammonia and bromthymol blue. (MVL)

  17. The Greenhouse Effect in a Vial.

    ERIC Educational Resources Information Center

    Golden, Richard; Sneider, Cary

    1989-01-01

    Presents an example of a greenhouse-effect experiment from the Climate Protection Institute. Analyzes the amount of carbon dioxide in ambient air, human exhalation, automobile exhaust, and nearly pure carbon dioxide by titrating with ammonia and bromthymol blue. (MVL)

  18. Non-Profit Greenhouse Gas Reductions Program

    EPA Pesticide Factsheets

    Baltimore City, Maryland, is an EPA Climate Showcase Community. EPA’s Climate Showcase Communities Program helps local governments and tribal nations pilot innovative, cost-effective and replicable community-based greenhouse gas reduction projects.

  19. Arctic climate change: Greenhouse warming unleashed

    NASA Astrophysics Data System (ADS)

    Mauritsen, Thorsten

    2016-04-01

    Human activity alters the atmospheric composition, which leads to global warming. Model simulations suggest that reductions in emission of sulfur dioxide from Europe since the 1970s could have unveiled rapid Arctic greenhouse gas warming.

  20. Advancing Greenhouse Gas Reductions through Affordable Housing

    EPA Pesticide Factsheets

    James City County, Virginia, is an EPA Climate Showcase Community. EPA’s Climate Showcase Communities Program helps local governments and tribal nations pilot innovative, cost-effective and replicable community-based greenhouse gas reduction projects.