Mate choice of an endogeic earthworm revealed by microsatellite markers

Endogeic earthworms are difficult study subjects due to the cryptic medium in which they live; thus, only the behaviour of epigeic and anecic earthworms has been studied before. We used microsatellite markers as a tool to elucidate the mate choice processes of Hormogaster elisae, an endogeic earthworm. It was shown to normally mate with two partners, preferably of the same size that are found in close proximity thereby eliminating the need for long-distance dispersion, which could explain the previously observed high genetic differentiation between populations. The genetic analyses of the sperm within each of its four spermathecae showed a uniform distribution with no signs of differential storage of sperm from different partners.     

An investigation of the relationship between the F1 potential and the measures of genetic distance among wheat lines

Summary Three groups of characters selected using three methods were used to calculate genetic distance among two groups of winter wheat lines using Euclidean distance based on principal components. These wheat lines were then clustered by the unweighted pair-group arithmetic average method. The relationship between genetic distance and standardized potence was seemingly influenced by genetic materials. In order to obtain promising crosses, it is advisable to select parents from intercluster rather than intracluster materials. The results suggested that the repeatability method was better than the conventional and weighting methods for selecting characters for distance analysis.     

论语境与翻译选词

本文旨在通过对决定语言意义的具体语言环境，即直接语言环境、间接语言环境及语言所蕴含的文化背景等三个方面进行全而的剖析，以期寻求如何正确地理解原文的含义以及如何把原文的含义在译文中巧妙体现出来的应对策略，并因此强调说明语境对翻译选词的重要影响和决定性作用。     

作物轮作方式产量效应模拟与优化选择研究

针对田间轮作试验周期长、工作量大的实际问题 ,采用作物生长模型 DSSAT3和 AL MANAC模拟研究了黄土高原典型地区作物轮作方式的产量效益 ,提出了轮作耗水系数、轮作耗氮系数和轮作经济收益值的概念与计算公式 ,并应用于作物轮作方式资源利用效率和经济效益评价 ,得出了关中平原区、渭北高原区和银川平原区的最优轮作方式分别为“小麦—玉米→小麦—玉米”一年二熟制、“小麦→小麦—谷子→玉米”三年四熟制和“小麦 /玉米→小麦 /玉米”套作一年二熟制     

水样中氟化物的测定方法比较

研究了氟离子选择性电极法和氟试剂分光光度法测定水样中氟化物的差异,探讨了2种方法的优劣.结果表明:电极法标准曲线的相关性好于分光光度法;氟化物浓度为5～10mg/L时,2种方法准确度和精密度在0.05水平上无差异;电极法的回收率高于分光光度法;电极法的最低检出限为0.011 mg/L,分光光度法的最低检出限为0.037mg/L.     

绿色营销是现代企业发展战略的必然选择

介绍了可持续发展及绿色营销的理念和特点，分析了企业开展绿色营销的外在要求和内在的原因，指出绿色营销是现代企业发展战略的必然选择，并就现代企业实施绿色营销的对策作了探讨。     

公共消费的理论创新与政策选择

公共消费包括政府自身消费和社会性消费,以公共风险为逻辑基础,并兼具经济和社会双重属性,既有利于维护经济稳定平衡,是可持续发展的基础;又有利于促进社会公平正义,是国民素质和社会文明程度提高的保障。目前理论界对公共消费问题的探讨大多基于经济视角,基于经济与社会双重视角审视公共消费理论,应树立“消费者主权”意识,明确我国公共消费政策方向。     

不同作物根系分泌物对黄瓜的化感作用

就不同作物根系分泌物溶液对黄瓜种子和黄瓜幼苗的化感作用进行了研究。结果表明,油菜、玉米、小麦和小白菜对黄瓜种子发芽势和发芽率的抑制作用均较低;除玉米根系分泌物溶液外,其余作物根系分泌物溶液均抑制黄瓜种子胚根和胚芽生长,且胚芽的受抑制强度大于胚根;玉米、油菜、小白菜和黄瓜根系分泌物溶液对黄瓜幼苗苗高和茎粗有促进作用,且对黄瓜幼苗根长和根数的抑制作用较小。说明玉米是黄瓜种植最适宜的前茬作物,其次是油菜和小白菜,而豇豆、豆角和黑豆等豆科作物不宜作为黄瓜种植的前茬作物。     

过水围堰导流方式选择的模糊层次综合决策

本研究应用层次分析法和模糊综合评判原理，提出了过水围堰导流方式选择的模糊层次综合评判方法     

On the Restricting Factors ＆ System Arrangements of Chinese Land Tenure Marketization

As a general rule of Economics of Development,economic growth and development require rational institution guarantee. Land Tenure. As a main institution factor in agricultural development ,closely relates to the reform of Chinese agriculture. Based on the relevant theories of Economics of Institution and Economics of Development ,and combined with the marketization process of Chinese Land Tenure of Property Rights,the article studied the effects of institutional factors and put forward some choices in the development of agriculture, which is of both significant and practical importance.