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Alan FRANZLUEBBERS Derek HUNT Gary TELFORD Shabtai BITTMAN Quirine KETTERINGS 《农业科学与工程前沿(英文版)》2021,8(1):81-96
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Variation in diosgenin levels among 10 accessions of fenugreek seeds produced in western Canada 总被引:1,自引:0,他引:1
Taylor WG Zulyniak HJ Richards KW Acharya SN Bittman S Elder JL 《Journal of agricultural and food chemistry》2002,50(21):5994-5997
A collection of 10 accessions of fenugreek (Trigonella foenum-graecum L.), an annual legume, was grown during two summers at three plot locations in western Canada to assess whether genetic (accession) and environmental factors (site and year of production) influenced levels of diosgenin, a steroidal sapogenin. The 60 harvested seed samples, each analyzed by single determinations on three subsamples of defatted and dried seed material, were hydrolyzed by a microscale procedure in water containing 2-propanol (70%) and sulfuric acid (1 M). The extracts were analyzed by capillary gas chromatography with 6-methyldiosgenin as internal standard. Diosgenin levels from mature seeds ranged from 0.28 to 0.92% (28-92 microg/10 mg). Analysis of variance on combined diosgenin levels from the three sites and two years revealed that accession, accession x year, and site x year effects were significant for diosgenin content, whereas site, year, and site x accession effects were not. Four accessions, CN 19062, CN 19067, CN 19070, and CN 19071, were identified with high levels of diosgenin on the basis of the 2-year data set. In these accessions, mean levels of diosgenin plus yamogenin from seven site years were estimated at 0.70, 0.98, 0.84, and 0.87%, respectively. 相似文献
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Saad El Din Hassan Aiguo Liu Shabtai Bittman Thomas A. Forge Derek E. Hunt Mohamed Hijri Marc St-Arnaud 《Biology and Fertility of Soils》2013,49(8):1109-1121
The effect of manure and mineral fertilization on the arbuscular mycorrhizal (AM) fungal community structure of sunflower (Helianthus annuus L.) plants was studied. Soils were collected from a field experiment treated for 12 years with equivalent nitrogen (N) doses of inorganic N, dairy manure slurry, or without N fertilization. Fresh roots of tall fescue (Festuca arundinacea Schreb.) grass collected from the field plots without N fertilization and unfumigated field soils were used as native microbial inoculum sources. Sunflower plants were sown in pots containing these soils, and three different means of manipulating the microbial community were set: unfumigated soil with fresh grass roots, fumigated soil with fresh grass roots, or fumigated soil with sterilized grass roots. Assessing the implications with respect to plant productivity and mycorrhizal community structure was investigated. Twelve AM fungal OTUs were identified from root or soil samples as different taxa of Acaulospora, Claroideoglomus, Funneliformis, Rhizophagus, and uncultured Glomus, using PCR-DGGE and sequencing of an 18S rRNA gene fragment. Sunflower plants grown in manure-fertilized soils had a distinct AMF community structure from plants either fertilized with mineral N or unfertilized, with an abundance of Rhizophagus intraradices-like (B2). The results also showed that AM inoculation increased P and N contents in inorganic N-fertilized or unfertilized plants, but not in manure-fertilized plants. 相似文献
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Katarina?R.?NeufeldEmail author Sue?J.?Grayston Shabtai?Bittman Maja?Krzic Derek?E.?Hunt Sean?M.?Smukler 《Biology and Fertility of Soils》2017,53(6):613-626
Removing solids from liquid dairy manure slurry reduces manure phosphorus (P) and increases the available (mineral) fraction of nitrogen (N) but also decreases the organic matter content of the manure. While this novel treatment reduces environmental concerns associated with excess N and P application to soils, it may also reduce microbial biomass and activity in soil. This study evaluated the long-term effects of this alternative manure treatment compared to more typical nutrient applications in a perennial grass sward (tall fescue, Festuca arundinacea Schreb.) on soil microbial biomass, community composition, hydrolytic enzyme activity, and forage yield. Nutrient treatments for this long-term field experiment in Agassiz, British Columbia, Canada were started in 2003. The treatments included liquid dairy manure slurry, liquid dairy manure with solids removed, commercial fertilizer, a combination of fertilizer and dairy manure, and a control. All treatments were applied at 400–600 kg total N ha?1 year?1 in four equal doses. Soil microbial community composition (phospholipid fatty acid analysis) and activity (hydrolytic enzyme activity) were determined several times during the 2013 and 2014 growing seasons to a depth of 15 cm. Time of sampling (date) had a strong influence on microbial biomass, community composition, and activity, while the response to soil properties and yield was more varied. All manure treatments (dairy manure slurry, liquid fraction, and the combination) increased microbial biomass (by 19–32%) and the potential activity of cellulose-degrading enzymes (by 31–47%) compared to commercial fertilizer and unamended plots. The commercial fertilizer and liquid fraction lowered fungal/bacterial ratios compared with both whole manure and unamended plots. Our results indicate that separating the solid from the liquid fraction of manure, to improve crop yield and reduce P loading, did not reduce microbial community size and activity and that all manure treatments increased microbial biomass and activity compared to mineral fertilizer application. 相似文献
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Tal Kanety Amos Naor Ami Gips Uri Dicken J. Hugo Lemcoff Shabtai Cohen 《Irrigation Science》2014,32(1):1-13
A 3-year irrigation trial provided basic information on the response of persimmon (Diospyros kaki cv. Triumph) water use and development to irrigation levels. Constant experimental factors applied to recommended “baseline” crop factors resulted in ratios of irrigation (I) to FAO56 reference crop evapotranspiration (ET0) ranging from 0.35 to 1.14. Vegetative and reproductive growth, sap flow, stem water potential (SWP), and local climate were monitored. An overall increase in yield and vegetative growth in response to irrigation was found, which suggests a potential yield increase for higher irrigation levels (40 tons/ha for annual irrigation of 1,000 mm). At high irrigation, the yield response curve levelled off and the marginal contribution of additional water declined. The up to threefold increase in number of fruits with irrigation, with no influence on natural abscission, suggests that differences in fruit quantities stem from response to irrigation at the earlier growth stages. Mean fruit size and fruit quality, as indicated by the ratio of rejected fruit, increased with irrigation up to I/ET0 of ~0.8. Relative yield increased linearly with relative transpiration. However, post-harvest quality was not influenced. SWP, sap flow, and non-transpirable water fractions indicated that the seasonal irrigation tables were not well tuned. Initial adjustments were made during the final season of the experiment and a new table was developed based on our results. The new table should be a basis for further trials. 相似文献
6.
Alon Ben-Gal Eviatar Ityel Lynn Dudley Shabtai Cohen Uri Yermiyahu Eugene Presnov Leah Zigmond Uri Shani 《Agricultural Water Management》2008,95(5):587-597
Maximization of crop yields when the salinity of irrigation water is high depends on providing plant transpiration needs and evaporative losses, as well as on maintaining minimum soil solution salinity through leaching. The effect of the amount of applied irrigation water was studied regarding transpiration, yields, and leaching fractions as a function of irrigation water salinity. Bell pepper (Capsicum annum L. vars. Celica and 7187) in protected growing environments in the Arava Valley of Israel was used as a case study crop to analyze water quantity–salinity interactions in a series of lysimeter, field and model simulation experiments. Leaching fraction was found to be highly influenced by plant feedback, as transpiration depended on root zone salinity. Increased application of saline irrigation water led to increased transpiration and yields. The higher the salinity level, the greater the relative benefit from increased leaching. The extent of leaching needed to maximize yields when irrigating with saline water may make such practice highly unsustainable. 相似文献
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网室内作物蒸散量的变化和影响要素研究 总被引:1,自引:0,他引:1
在香蕉种植网室内,研究了网室内外作物蒸散量和参考作物蒸散量的关系,以及网室内小气候变化对参考作物蒸散量的影响.研究结果显示,网室内参考作物蒸散量(ET0)和A级蒸发皿水面蒸发量分别比大田减少39%和42%,网室内香蕉树蒸腾量较网室外下降53%.网室内净辐射降低和风速减小是网室内香蕉树蒸腾量和参考作物蒸散量降低的主要原因,而网室内温度和饱和水汽压差变化对蒸散量的影响较小.建立了网室内参考作物蒸散量和网室内外水面蒸发量的关系,计算出该地区的A级蒸发皿系数为0.84. 相似文献
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Matthias Langensiepen Marcel Fuchs Homero Bergamaschi Samuel Moreshet Yehezkel Cohen Peter Wolff Samuel C. Jutzi Shabtai Cohen Luis Mauro G. Rosa Yan Li Thomas Fricke 《Agricultural and Forest Meteorology》2009,149(6-7):1063-1072
The uncertainties of transpiration calculations with the Penman–Monteith equation were quantified under different climate conditions of Brazil, Germany and Israel using maize as a common crop type. All experiments were carried out under non-limiting growing conditions. Canopy resistance was determined by scaling to canopy level specific relations between in situ measurements of incident radiation and stomatal conductance using a light penetration model. The model was tested against heat-pulse measured sap flow in plant stems. The root mean square error (RMSE) of daily calculated transpiration minus measured sap flow was 0.4 mm/day. It was dominated by its variance component (variance = 0.2 {mm/day}2; bias = 0.0 mm/day). Calculated transpiration closely matched the measured trends at the three locations. No significant differences were found between seasons and locations. Uncertainties of canopy conductance parameterizations led to errors of up to 2.1 mm/day. The model responded most sensitively to a 30% change of net radiation (absolute bias error = 1.6 mm/day), followed by corresponding alterations of canopy resistances (0.8 mm/day), vapour pressure deficits (0.5 mm/day) and aerodynamic resistances (0.34 mm/day). Measured and calculated 30-min or hourly averaged transpiration rates are highly correlated (r2 = 0.95; n = 10634), and the slope of the regression line is close to unity. The overall RMSE of calculated transpiration minus measured sap flow was 0.08 mm/h and was dominated by its variance component (0.005 {mm/h}2). Measured sap flow consistently lagged behind calculated transpiration, because plant hydraulic capacitance delays the change of leaf water potential that drives water uptake. Calculated transpiration significantly overestimated sap flow during morning hours (mean = 0.068 mm/h, n = 321) and underestimated it during afternoon hours (mean = ?0.065 mm/h; n = 316). The Penman–Monteith approach as implemented in the present study is sufficiently sensitive to detect small differences between transpiration and water uptake and provides a robust tool to manage plant water supply under unstressed conditions. 相似文献