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Two commercial hard red spring wheat cultivars were exposed to high and low temperatures, as well as drought stress when the main tiller kernels were at the soft dough stage. The trial was done in the greenhouse for two consecutive seasons to determine the effects of these stress conditions on protein content, SDS sedimentation and selected Mixsmart characteristics. Heat stress had the largest effect on mixing characteristics. Heat and drought stress caused a significant increase in flour protein content of both cultivars and had similar effects on mixing characteristics. The Mixsmart characteristics associated with dough strength were increased by heat and drought stress. Cold stress caused a slight increase in protein content of the cultivars, but in general caused a reduction in dough strength as measured with Mixsmart characteristics. The reaction of Mixsmart characteristics to heat and drought stress was much larger in Duzi than in Kariega, confirming that there is a large genotype effect in rheological characteristics. 相似文献
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Xiao Hui Li Jun Jie Bai Xing Ye Yin Chang Hu Sheng Jie Li Ling Yun Yu 《Fisheries Science》2009,75(2):351-358
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白粉病是瓜类作物重要病害之一。本研究采用苗期人工接种方法,研究了117份瓠瓜微核心种质对白粉病的抗性,并基于不同材料的病情指数和基因型数据,进行全基因组关联分析(genome-wide association analysis,GWAS)。利用2014年和2018年的抗病表型数据,分别鉴定到22个和13个与白粉病抗性相关的SNPs,其中2个SNPs位点在两年试验中同时被检测到。进一步研究发现不同瓠瓜材料的白粉病抗性与其携带有利等位变异数目成正相关。本研究为克隆瓠瓜抗白粉病相关基因、研究其抗病机制提供科学依据,促进了瓠瓜抗白粉病分子育种。 相似文献
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为了快速准确地掌握棉花虫害发生趋势,提高虫情测报的时效性和准确性,采用Apriori算法数据挖掘关联规则,对棉花上的3种害虫棉铃虫、棉叶螨、棉蚜的发生趋势进行综合分析。通过Apriori算法寻找出了气候因素与棉花三大害虫的发生发展有密切的关系,尤其气温变化直接影响到棉花害虫的发生种类、发生期及发生量。联规则数据挖掘技术,在处理大量农业信息数据中起着非常重要的作用,Apriori算法在棉花病虫测报工作中将是一项新的技术,具有非常广泛的应用前景。 相似文献
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Hydrophobic chlorinated hydrocarbons are adsorbed onto particles in the environment. Thus, uptake of chlorinated hydrocarbons into organisms is likely to be from the particle-adsorbed state. We investigated the transfer of chlorinated hydrocarbons from particles to phospholipid membranes, quantified by quenching of the fluorescence of a carbazole-labeled phospholipid which was used to label the membranes. The chlorinated hydrocarbons studied included DDT, DDE, methoxychlor, lindane, stirofos, and several polychlorinated biphenyls. The particles studied were porous glass, kaolinite, cellulose, and silica. Transfer of chlorinated hydrocarbons from particles to vesicles was independent of the chlorinated hydrocarbon concentration. The transfer rate did not depend on binding of lipids to particles, and was independent of the lipid composition of the vesicles. Membrane uptake of chlorinated hydrocarbons from the particle-adsorbed state was more rapid than uptake from the microcrystalline state, and uptake was faster when the chlorinated hydrocarbons were dispersed over larger particle surface areas. The transfer rates of chlorinated hydrocarbons correlated with their aqueous solubilities. In total, these results indicate that chlorinated hydrocarbons are transferred through the aqueous phase. We judge the rate-limiting step in membrane uptake to be the rate of solubilization of the chlorinated hydrocarbons from the particles into the bulk aqueous phase. Adsorption of chlorinated hydrocarbons onto particles may enhance the transfer rate by dispersing the chlorinated hydrocarbons and making them more available for solubilization in the bulk aqueous phase. The data are correlated with a model that assumes diffusion across an unstirred aqueous layer which interfaces with the bulk aqueous phase and the particle. 相似文献