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排序方式: 共有446条查询结果,搜索用时 15 毫秒
91.
92.
Nimesha Fernando Joe Panozzo Michael Tausz Robert M. Norton Glenn J. Fitzgerald Samuel Myers Cassandra Walker James Stangoulis Saman Seneweera 《Journal of Cereal Science》2012
We investigated wheat (Triticum aestivum) grain quality under Free Air CO2 Enrichment (FACE) of 550 ± 10% CO2 μmol mol−1. In each of two full growing seasons (2008 and 2009), two times of sowing were compared, with late sowing designed to mimic high temperature during grain filling. Grain samples were subjected to a range of physical, nutritional and rheological quality assessments. Elevated CO2 increased thousand grain weight (8%) and grain diameter (5%). Flour protein concentration was reduced by 11% at e[CO2], with the highest reduction being observed at the late time of sowing in 2009, (15%). Most of the grain mineral concentrations decreased under e[CO2] - Ca (11%), Mg (7%), P (11%) and S (7%), Fe (10%), Zn (17%), Na (19%), while total uptake of these nutrients per unit ground area increased. Rheological properties of the flour were altered by e[CO2] and bread volume reduced by 7%. Phytate concentration in grains tended to decrease (17%) at e[CO2] while grain fructan concentration remained unchanged. The data suggest that rising atmospheric [CO2] will reduce the nutritional and rheological quality of wheat grain, but at high temperature, e[CO2] effects may be moderated. Reduced phytate concentrations at e[CO2] may improve bioavailability of Fe and Zn in wheat grain. 相似文献
93.
94.
微喷灌结合滴灌对温室高温环境和作物生长生理特性的影响 总被引:1,自引:3,他引:1
微喷灌结合滴灌是指在作物根区滴灌的基础上对作物冠层进行微喷灌来改善作物生长环境的一种灌水方式。为了探明微喷灌结合滴灌(micro-sprinkler irrigation combined with drip irrigation,MSDI)和地表滴灌(surface drip irrigation,SDI)2种灌水方式下温室高温环境及作物生长生理特性的差异及响应规律,该研究以黄瓜为试验对象,于2017年2-6月开展了2种灌水方式下温室环境及黄瓜生长生理特性的观测试验。结果表明:在改变温室环境方面,MSDI灌水方式较SDI可增加温室内相对湿度,降低气温,同时降低叶片温度约4℃;在作物生长生理特性方面,采用MSDI可增加黄瓜株高与茎粗,降低作物茎流速率,促进黄瓜生长;2种灌水方式下黄瓜最大光合效率几乎一致,分别为0.74和0.77,但日平均实际光合效率差异明显,分别为0.57和0.47,MSDI灌水方式下黄瓜叶片日平均气孔导度和光合速率比SDI方式分别高182.8%和92.4%。该研究成果对于合理调控温室高温环境、提高温室作物产量具有重要的指导意义。 相似文献
95.
Mak Chanratana Gwang Hyun Han Manoharan Melvin Joe Aritra Roy Choudhury Seshadri Sundaram Md. Abdul Halim 《Archives of Agronomy and Soil Science》2018,64(11):1489-1502
Methylobacterium oryzae CBMB20, a promising plant growth promoting bacteria (PGPB) and a biocontrol agent, was immobilized in different formulations such as wet chitosan, dry chitosan, wet alginate and dry alginate and were tested for tomato plant growth promotion. Chitosan solution (1.5%) with pH 5.5–6.0 and 90 min contact time was found optimal for immobilization. The chitosan formulations showed better entrapment efficiency and good degradability resistance apart from slow release of cells under prolonged incubation. Survivability of bacteria (80%) was observed in wet chitosan formulation even after 90 days of storage at 4°C. The spermosphere survival of bacteria was high in both dry and wet chitosan formulations applied soils even after 21 days under greenhouse conditions. While the alginate formulation degraded fully, partial degradation of chitosan formulation was observed even after 30 days, indicating its ability to support the survival of M. oryzae CBMB20 in soil. Plants inoculated with wet chitosan formulation registered 1.3 fold increase in the shoot and root length and dry weight compared to other treatments. Hence, chitosan formulation supporting better plant growth compared to alginate will be a better carrier for taking bacteria to the plant rhizosphere and thereby promote plant growth. 相似文献
96.
基于修正双作物系数模型估算温室黄瓜不同季节腾发量 总被引:1,自引:5,他引:1
为估算温室黄瓜植株蒸腾与土面蒸发,该研究基于FAO-56推荐的双作物系数模型,应用温室内实测微气象、叶面积指数(LAI)及土壤水分数据,对模型中基础作物系数(Kcb)和土面蒸发系数(Ke)进行修正,并基于修正后FAO-56Penman-Monteith(P-M)模型,确定温室参考作物蒸发蒸腾量(ET0),进而估算温室黄瓜蒸发蒸腾量(ETc)和植株蒸腾(Tr)。基于Venlo型温室内黄瓜不同种植季节(春夏季和秋冬季)Lysimeter和茎流计观测的黄瓜ETc和Tr,对修正后的双作物系数模型预测结果进行验证。结果表明,应用修正后的双作物系数模型估算的温室黄瓜ETc和Tr与实测值具有较好地一致性,春夏季温室黄瓜全生育期ETc估算值与实测值的日均值分别为3.05和2.94 mm/d,秋冬季分别为2.53和2.76 mm/d。修正后的双作物系数模型估算春夏季温室黄瓜日ETc的决定系数(R2)、均方根误差(RMSE)和模型效率系数(Ens)分别为0.95、0.41 mm/d和0.93;估算秋冬季ETc的误差计算结果依次为0.91(R2)、0.48 mm/d(RMSE)和0.90(Ens)。修正后的双作物系数模型估算春夏季日平均Tr与实测值分别为2.37和2.19mm/d,秋冬季分别为1.43和1.34 mm/d。研究结果还显示,不同种植季节温室黄瓜全生育期日平均Tr占ETc的比例分别为64.62%(春夏季)和68.59%(秋冬季)。该研究成果不仅为制定准确的温室黄瓜灌溉制度提供了理论依据,而且对实现温室环境智能化控制及减少温室内无效的土面蒸发具有重要意义。 相似文献
97.
98.
William J. Hornof DVM MS Philip D. Koblik DVM MS Donald R. Strombeck DVM PhD Joe P. Morgan DVM Vet med dr Greg Hansen 《Veterinary radiology & ultrasound》1989,30(6):242-248
A technique for scintigraphically quantitating solid-phase gastric emptying in the dog was developed in a Beagle model. The test meal was determined to empty in a linear fashion, indicating a solid-phase label. The evaluation was performed on a group of dogs presented for gastrointestinal signs that were judged to have normal liquid barium sulfate fluoroscopic and radiographic studies. The results of this study indicate that this technique is valuable for identifying those patients with surgically correctable pyloric obstruction that exhibit normal gastric emptying of liquid barium. 相似文献
99.
MAGNETIC RESONANCE IMAGING OF THE NORMAL FELINE BRAIN 总被引:2,自引:1,他引:1
Lola C. Hudson DVM PhD Laurent Cauzinille DVM Joe N. Kornegay DVM PhD Mary B. Tompkins DVM PhD 《Veterinary radiology & ultrasound》1995,36(4):267-275
The Purpose of this study was to produce an atlas of magnetic resonance images (MRI) of the feline brain and associated structures. The head of nine clinically normal cats was imaged in 2 or 3 anatomic planes and 3 sets of technical parameters resulting in T1, T2, and proton-weighted density images. Images were compared with anatomic texts, with preserved and sectioned feline cadaver heads, with preserved and sectioned feline brains, and with intact, sectioned, and disarticulated feline skulls for aid in identification of structures. Anatomic and neuroanatomic structures are identified on selected images in different planes as reference for MR morphology of the normal feline brain and related structures. 相似文献
100.
Clark S. Patton Rhonda Hake Joe Newton Robert L. Toal 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1996,10(3):139-142
Chronic esophagitis due to Pythium insidiosum infection caused weight loss, dysphagia, and hypersalivation in 2 dogs from rural Tennessee. Although dog 1 presented for evaluation in December 1984 and dog 2 in October 1992, infection likely occurred during the previous summer by drinking fresh pond water containing zoospores. Hematologic testing revealed eosinophilia and hypergammaglobulinemia in one dog. An etiologic diagnosis was not made until postmortem evaluation when hyphae within necrotic and granulomatous cellular infiltrates in the esophageal wall were identified as P insidiosum by immunoperoxidase staining. Failure to culture the organism from the esophageal wall in dog 2 was attributed to refrigeration of the tissues, since refrigeration decreases the survivability of P insidiosum. J Vet Intern Med 1996;10:139–742. Copyright © 1996 by the American College of Veterinary Internal Medicine . 相似文献