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911.
EIN3 Binding F-box protein (EBF) is an essential signaling component necessary for ethylene response. However, little information is available on EBF genes during banana fruit ripening. Two EBF genes designated MaEBF1 and MaEBF2 were isolated and characterized from banana fruit. Subcellular localization analysis showed that MaEBF1 and MaEBF2 were both nuclear proteins. Expression of MaEBF1 and MaEBF2 in fruit with four ripening characteristics revealed that MaEBF2 was enhanced by ethylene during fruit ripening, while MaEBF1 changed only slightly. Moreover, the MaEBF2 promoter was activated after ethylene treatment, further supporting its involvement in fruit ripening. More importantly, MaEBF2 was shown to physically interact with MaEIL5, using yeast two-hybrid (Y2H) and bimolecular fluorescence complementation (BiFC) assays. Together, these results suggest that MaEBF may be involved in banana fruit ripening, at least partly via interaction with MaEIL5. Our findings expand our understanding of the regulatory network of ethylene signaling cascade in banana fruit ripening.  相似文献   
912.
[目的]计算机技术飞速发展之际,设计并开发一个完善的中草药管理系统对药材信息进行有效管理,具有一定的社会意义和应用价值。[方法]以MicrosoftVisualBasic6.0为主导设计软件,设计人机交互界面,利用MicrosoftOfficeAccess2007建立.Jet数据库,开发出中草药鉴定及资源信息库。[结果]通过该系统,用户可以按中草药的药材名称、药材异名、性状、功能、服用禁忌、采集加工和资源利用等信息进行单项检索,还可以通过多项信息组合的方式进行检索;也可以先按形态学特征进行分类鉴定后,浏览药物的各类属性。[结论]该系统能为生产、教学、科研和管理决策等提供高效服务。  相似文献   
913.
施用氮磷钾肥对水稻产量的影响及养分交互作用研究   总被引:1,自引:0,他引:1  
为探讨氮磷钾肥料施用对水稻产量的影响以及氮、磷、钾养分交互作用,以水稻为研究对象,进行氮磷钾配比试验。结果表明:氮、磷、钾肥之间存在一定的交互作用,本试验条件下,N—195.0kg/hm^2、P2O5—60kg/hm^2、K2O—150kg/hm^2时最有利于各养分效果的发挥,氮、磷、钾肥合理配施对水稻产量有重大影响。  相似文献   
914.
为了探明河北省农村人口与环境系统的关系,运用主成分分析方法,从人口数量、人口素质、人口结构和人口消费4方面对河北省农村人口与环境系统协调发展的关系进行分析.结果表明:河北省农村人口的综合发展水平明显提高,环境综合发展水平大幅下降,两系统协调系数的波动性较大,系统间的矛盾较为突出.因此,要实现河北农村人口与环境的协调发展,必须提高农村居民的环保意识,统筹城乡基础设施建设,大力发展农业循环经济.  相似文献   
915.
抽穗期是水稻重要的农艺性状,它决定水稻品种的地域适应性和季节适应性,是重要的育种目标之一。本研究从两个水稻单片段代换系杂交分离群体中筛选到8个次级单片段代换系和2个双片段聚合系,经重叠群作图分析,鉴定出2个与抽穗期有关的QTL。qHD3位于第3染色体短臂,qHD6位于第6染色体的短臂中部。在长日照条件下,Lemont的qHD3等位基因可促进水稻早抽穗,Tetep的qHD6等位基因则延迟水稻抽穗。另外,上位性分析表明,在长日照条件下,qHD3和qHD6之间存在着显著的上位性互作效应。  相似文献   
916.
917.
Abstract

Genetic and environmental sources of variation in skin and fur characteristics were estimated within and between populations in a two year mink progeny testing scheme with approximately 200 paternal progeny groups. Animals from several populations were housed at a central test station, and corresponding full-sibs were kept at the farm of origin. Data were analysed with an animal model to estimate heritabilities, common litter effects and fixed effects due to population and environment. Genetic variation within and between populations was found, together with significant environmental effects, indicating potential improvements in the breeding scheme. An interaction of sex with population and environment was considered and found significant for traits with a large sex dimorphism. Common litter effects were unimportant for traits measured, except for length and weight of skin. Discrete, subjectively measured traits are analysed with a linear model and a threshold model.  相似文献   
918.
ABSTRACT

Field trials were carried out during 2011–2013 in three locations on 10 wheat genotypes. Traits that were investigated included grain weight, grain-filling duration, grain-filling rates and the lag phase from flowering to the commencement of effective grain filling. The grain-filling duration and rate were fitted by Richard’s equation in thermal time (growing degree-days (GDD), base temperature 9ºC). A combined ANOVA across environments showed that the grain weight was mainly affected by genotype, while most of the other grain-filling characters were influenced by the environment and G × E interactions. Grain filling lasted between 362 to 400 GDD and included a lag phase that ranged from 67 to 86 GDD. Both the effective and maximum rates of grain filling ranged from 0.12 to 0.15 mg GDD?1 and 0.18–0.22 to GDD?1, respectively. The lag phase was positively correlated with grain weight and rates of grain filling, whereas days to anthesis were significantly negatively correlated with the lag phase and both rates of grain filling. Temperature during grain filling was negatively correlated with the lag phase. The variation in grain weight was positively associated with the rate of grain filling, which, in turn, was related to the grain number per unit area. A compensating variability existed among the genotypes in both the grain number and grain-filling rate. The study of genotypic stability demonstrated that Chuanmai42 and Chuanmai104 had high grain weight and stability among most of the grain-filling parameters, and also had high grain yield. Chuanmai42 and Chuanmai104 were the best genotypes for improving the yield potential and grain weight stability.  相似文献   
919.
Abstract

Wheat provides nutrients and the raw materials for industrialized food production. Recent global economic trends and increases in urban population growth have led to an increased demand for wheat-based convenience foods (fast, ready-to-eat, frozen foods, etc.) and for new wheat-based products. These factors have resulted in a greater emphasis than ever on the end-use quality of wheat. This paper reviews grain compositional aspects influencing the processing and quality attributes of the main foods produced with wheat, as well as the breeding strategies and methodologies used to achieve germplasm with desirable end-use quality. Common wheat (Triticum aestivum) is used in bread (leavened, flat, and steamed), noodles, biscuits, and cakes. Durum wheat (T. turgidum L. var. durum) is used globally in alimentary pasta and regional foods (flat breads, couscous, and burghoul) in North Africa and West Asia. Grain characteristics (grain hardness, protein content/quality, enzymatic activity, etc.) play a moderate to important role in the processing and end-use quality of wheat-based products. Among these, gluten strength and extensibility, which are determined by glutenin (HMW and LMW) and gliadin composition, are two of the main factors that determine quality. The complex and generally additive nature of inheritance of most quality traits has led to the development of several indirect tests used in early and advanced generations to increase the frequency of high yielding lines with desirable quality attributes. Additionally, characterization of HMW and LMW glutenins and gliadins allows breeders to combine protein content and quality more effectively. The use of molecular-marker-assisted selection and genetic transformation is expected to accelerate the tailoring of new wheat varieties to meet specific end-use quality requirements. Accumulating desirable quality genes will help reduce genotype X environment effects on quality-presently among the major challenges confronting breeders.  相似文献   
920.
李明  张言召  韩振乾 《安徽农业科学》2013,(32):12554-12556
白斑综合征病毒(White spot syndrome virus,WSSV)是严重危害对虾养殖业的病原之一。随着WSSV基因组全序列的公布及蛋白质组学的飞速发展,对WSSV结构蛋白及其相互作用的研究越来越深入。通过对WSSV结构蛋白及其相互作用的分析,进一步研究其在病毒感染过程中的作用,这为有效控制甚至阻断WSSV感染奠定基础。  相似文献   
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