Combining Ability and Parent-Offspring Correlation of Maize（Zea may L.） Grain β-Carotene Content with a Complete Diallel

Vitamin A deficiency has become a worldwide problem.Biofortified foods can potentially be an inexpensive,locally adaptable,and long-term solution to dietary-nutrient deficiency.In order to improve the β-carotene content in maize grain by breeding and minimize vitamin A deficiency,a complete diallel cross was designed with eight inbred lines of maize,and 64 combinations were obtained in this study.The experimental combinations were planted in Yunnan and Sichuan provinces,respectively,with a random complete block design.The β-carotene contents in the grains of the experimental materials were analyzed by high-performance liquid chromatography.Among the tested materials,the effect difference of general combining ability of the β-carotene content was significant;however,the effect difference of the special combining ability and the reciprocal effect were not significant.The β-carotene content of maize grain was not influenced significantly by the cross and the reciprocal cross.There was a significant correlation about the β-carotene content in the maize grains between the F 1 and their parents.The combinations with high β-carotene content were obviously influenced by the environment,and the mean value of β-carotene content for the experimental materials planted in Ya’an of Sichuan was higher than that planted in Yuanjiang of Yunnan,with the results being significant at the 0.01 level.     

陆地棉主要经济性状的配合力和遗传力分析

本研究以４个南疆自育中熟陆地棉品种（系）和在新疆引种推广的５个中棉所系列品种为材料，采用不完全双列杂交设计，对１３个经济性状作了配合力和遗传力分析。结果表明，南疆自育品种（系）单铃重、第一果枝高度主要受基因加性效应控制，中棉所品种的第一果枝节位、２．５％跨长、马克隆值、伸长率主要受加性效应控制，而在株高、果枝数性状上两类亲本主要受非加性效应控制，衣分同时受加性和非加性效应控制。衣分、２．５％跨长、单铃重的广义和狭义遗传力较高，宜在早代选择     

Diallel analysis of sugar composition of 10 vegetable soybean lines

Few studies have evaluated vegetable soybean for sugar content at the green pod stage. Information on combining ability and type of gene action that governs inheritance of seed traits can help breeders to select suitable parents and devise an appropriate breeding strategy. Ten vegetable soybean accessions were crossed in a complete diallel mating design. Parent lines and F₂ and F₃ progenies were evaluated for two nutritional components. In this study, both general and specific combining ability and reciprocal effects were significant for sucrose and total sugar. Cultivars 'Kanrich', 'Pella', 'Verde' and V81-1603 had good general combining ability for high sucrose. In general, high sucrose content was observed in progeny of the early maturity group genotypes 'Kanrich', 'Pella' and 'Verde'. The best combiners for high total sugar content were 'Verde', V81-1603 and PI 399055. These genotypes could serve as genetic sources in a vegetable soybean breeding programme.     

Rooting response of late summer cuttings taken from Pinus sylvestris half-sib families

Abstract

One-year-old Pinus sylvestris donor plants were top-pruned in early May, allowing cuttings of three types to develop: shoots from adventitious buds near the top of the plant (T), weaker shoots from adventitious buds emerging further down the stem (M) and shoots from normal buds on branches (B). Cuttings from 46 half-sib families were collected at the beginning of August, treated with indole-butyric acid, immediately inserted in containers with porous substrate and put in a greenhouse, where soil was heated and high air humidity was maintained. The rooting frequency, estimated by counting living plants 10 months after insertion, was 54%. The family variance component for rooting was small and non-significant, while the clone-within-family component was strongly significant and accounted for 21% of the total random variance. Type M and type B cuttings showed significantly better rooting ability than type T cuttings. Including only plants with at least four acceptable shoots in the propagation experiment, 61% of the potential donor plants remained, without loss of any family. If a more restricted selection criterion was applied, including only plants with at least eight acceptable shoots, 21% remained, with a loss of 13 families. It was concluded that rooting ability of P. sylvestris can be brought to a level that could justify its inclusion in a breeding programme. The lack of family variation was also favourable in this respect, as no families were lost owing to low rooting response. However, the number of suitable cuttings produced by the donor plants needs to be increased.     

拟澳洲赤眼蜂和短管赤眼蜂在菜芯地的扩散动态

在不同生长期的菜芯地释放赤眼蜂防治小菜蛾，当蜂量为2000头／点时，拟澳洲赤眼蜂在田间的有效扩散距离(寄生率大于60％)，苗期为3米，生长中期和收获期为4米。短管赤眼蜂在田间的有效扩散距离，苗期和生长中期为4米，收获期为5米，较拟澳洲赤眼蜂具有更强的扩散能力。     

提升政府执行力对构建和谐新农村的意义及实现途径

当前我国在构建和谐新农村的过程中,经济和社会发展中的问题以及潜伏的深层次的问题日益凸现.政府执行力是政府的核心要素之一,是政府履行职责与提高自身存在合法性的重要前提.政府执行力与和谐新农村具有一定的同构性和互补性,提升政府执行力对于构建和谐新农村具有十分重要的意义.提升政府执行力需要培育良好的政府执行力文化环境,进行政府人事管理制度创新,提高政府人员的素质,建立健全对农村的利益补偿和调节机制.     

论不同饲料添加剂对獭兔生产性能的影响

糖萜素饲料添加剂的推广应用,将加快我国饲料和畜禽养殖业的安全绿色进程,对提高人民健康水平,实现动物源性食品安全绿色化,特别是解决药物残留问题,加快畜产品出口创汇,具有十分重要的意义。     

花期喷施生长调节剂和氨基酸肥对枣树结实和育性的影响

以两个枣品种为试材,研究了花期喷施生长调节剂和氨基酸肥对自花授粉和自然授粉条件下的结实及种仁发育的影响。结果表明,低浓度的GA3(5~10 mg/L))虽可提高枣树的结实率但降低了枣果的可育率,当GA3浓度达到35 mg/L时结实率亦降低;150 mg/L的6-BA0、.02 g/L氨基酸肥对自花结实率、自然结实率、自然可育率都有降低作用。     

10种热带牧草根际高效解磷细菌的筛选及其培养条件

从热研2号柱花草等10种不同牧草中筛选出9株无机解磷细菌及6株有机磷细菌,并利用平板溶磷圈法、钼锑抗比色法对分离得到的细菌进行测定,最后得到解磷效果最好的解磷细菌株,牧草根际解无机磷细菌解磷能力最高达216.57 mg/L.选定2株具有代表性的解无机磷细菌GI2-6(Bacillus spp.)和GI9-4-3(Serratia spp.),通过单因子试验对其解磷特性和培养条件进行研究,结果表明:当解磷细菌GI2-6以蔗糖为碳源、KNO_3为氮源、pH为7.5、温度为30℃,解磷细菌GI9-4-3以葡萄糖为碳源、KNO_3为氮源、pH为7.0、温度为30℃时,两者的菌体量最大,解磷效果最好.     

高校图书馆特色服务研究

从特色服务的概念及特点出发，本文阐述了高校图书馆开展特色服务的必要性及应遵循的原则，并介绍了我馆几种主要的特色服务方式。