Statistical discrimination between pollen tube growth and seed set in establishing self incompatibility in Gaura lindheimeri 1

The University of Minnesota Gaura breeding program is developing USDA Z3-4 winter-hardy genotypes via interspecific hybridization of G. lindheimeri (Z5-6) and G. coccinea (Z2-4). Prior to commencing interspecific hybridization, the reproductive barriers operating in both parental species need to be characterized. The objective of this research was to determine the type and stability of reproductive barriers operating in G. lindheimeri by statistical comparisons between pollen tube growth and seed set in a full-sib diallel. Slowed or aborted pollen tube growth in the style indicated the presence of a gametophytic self incompatibility (SI) system. A statistical method, female (FCC) and male (MCC) coefficients of crossability, was used to verify that a stable SI system was operating and that other reproductive barriers were present. Several genotypes also expressed stage-specific inbreeding depression and incongruity. The simple linear regression equation for FCC/MCC, using pollen tube growth, was Y = 0.0124 + 0.974X, which was much closer to the expected Y = 0.0 + 1.0X (indicating a stable SI system) than the equation for seed set, Y = 0.012 + 0.910X. Using pollen tube length, both general combining ability (GCA) and specific combining ability (SCA) values were highly significant for G. lindheimeri (P ≤ 0.001). Histograms were used to delineate cut-offs to identify intra-incompatible/inter-compatible classes and S allele groups. Four possible classes were identified, but further research is needed to verify S allele genotypes.Scientific Research Paper No. 031210120 of the Department of Horticultural Science. This research was supported by a grant from the Perennial Plant Association and, in part, by the Minnesota Agricultural Experiment Station     

黄瓜主要品质性状配合力分析

以８个高代自交系为试材，按不完全双列杂交法配制１６个组合，并进行了配合力分析。供试８个亲本中，有１个亲本平均单瓜重、瓜把长度具有较大的正向效应值；有１个亲本瓜粗、心室直径具有较大的负向效应值。在所配的１６个组合中，有３个组合的平均单瓜重表现出较大的正向效应值，有３个组合的瓜把长度表现出较大的负向效应值。瓜条粗度和心室大小的特殊配合力在组合间表现出较大差异，瓜把长和平均单瓜重狭义遗传力较低，而瓜条长     

Inheritance of Corolla Size, Number of Stamens and Percentage of Plants with Petaloid Stamens in Evergreen Azaleas (Rhododendron Subsect. obtusa)

Research has been carried out on the inheritance of corolla size, number of stamens and percentage of plants with petaloid stamens (double flower) in evergreen azaleas (Rhododendron Subsect. obtusa). For this purpose two incomplete diallel crosses were used. The first one included seven species and one cultivar and the second diallel 13 cultivars. In both diallels for all three characters the GCA mean squares were high. Also, the positive correlation between the parental values and the GCA estimates for flower size and number of stamens indicates that the expression of these characters is mainly determined by additive gene action. A negative correlation was found between GCA estimates for die n number of stamens and the percentage of plants with petaloid stamens. When breeding azaleas with large double flowers, parents can be directly selected on the basis of these characters since additive genetic variance dominates. As no genetic correlations were found between corolla size and number of stamens (percentage of plants with petaloid stamens) the breeding will not be hampered by unfavourable linkage of genes for these characters.     

我国蚕业科研机构创新能力的评价与分析

基于为蚕业科研机构正确制定创新战略,提高科研创新能力提供依据的目的,运用层次分析法构建了我国蚕业科研机构创新能力评价指标体系。根据现有19家蚕业科研机构的统计数据,对我国蚕业科研机构的创新能力进行综合评价,并对评价结果进行客观的分析,认为：必须加大对蚕业科研机构的投入,重视蚕业科技人才队伍建设,深化蚕业科研体制改革。     

红菜薹主要矿质元素的配合力分析 

利用不完全双列杂交法,对新育成的红菜薹胞质雄性不育系Eru-3、Eru-5和16个父本材料配制的32个杂交组合进行主要矿质元素Ca、Mg、Fe、Zn的配合力和遗传力分析。结果表明:雄性不育系Eru-5和父本D、E、F和H的一般配合力较高,是提高杂种一代矿质元素含量的理想亲本;组合Eru-5×G、Eru-5×H和Eru-3×L具有较好的特殊配合力效应,是矿质营养价值较高的优良杂交组合。遗传力分析表明:Ca主要受基因加性效应控制,Mg、Zn的遗传由加性和非加性基因效应共同控制,Fe主要由非加性基因效应控制。     

轮回选择对豫综5号玉米群体产量性状配合力的改良效果

玉米群体遗传基础广泛、遗传变异丰富,是培育优良玉米自交系的源泉。玉米群体的改良研究对玉米种质资源创新、优良自交系选育具有重要的指导意义。本研究采用NC II遗传交配设计,以豫综5号5个轮次改良群体为父本,以黄早四、丹340、中综5号、齐319、掖478、Mo17为测验种配制成30个测交组合,通过一年两点的产量性状及其配合力评价试验,研究轮回选择对豫综5号群体的改良效果。结果表明,轮回选择对群体单株产量的改良是有效的,群体与各测验种间的杂交后代产量平均每轮提高3.57%。半姊妹轮回选择和相互半姊妹轮回选择在改良群体产量一般配合力方面, 均得到显著提高,呈逐轮上升的趋势;采用半姊妹轮回选择对豫综5号群体3轮的选择后,C₃群体与C₀相比,一般配合力效应值从–11.63增长到5.57,差异极显著;经1轮相互半姊妹轮回选择后,群体的一般配合力效应值从C₃的5.57增加到C₄的9.75。豫综5号改良群体与黄早四的特殊配合力得到一定的提高,逐轮朝着Reid×唐四平头杂优模式水平提高的方向稳定发展。     

12个外来玉米群体与我国主要种质配合力效应和杂种优势分析

国际玉米小麦改良中心(CIMMYT)和美国玉米带种质含有丰富的遗传变异, 是拓展我国玉米种质基础的重要来源。本文采用NCII遗传交配设计, 以中综5号、中综6号和中综7号综合种为测验种, 与12个外来群体配制36个组合。以郑单958为对照, 2009—2010年分别在北京顺义、山东济南和河南新乡进行产量及相关性状测定。利用Miranda Filho-Geraldi模型, 评价外来群体主要性状配合力效应及杂种优势表现。结果表明, Pob43、La Posta、Pob21、Pob32、Pob49、Pob501等群体的产量及相关性状GCA表现优良。群体Pob49、Pob501与我国PA种质, Pob32、BS29与我国PB种质, Pob43、La posta与我国D群四平头种质的遗传关系较近。因此, 在改良外来群体适应性的基础上, 可以我国A、B和D类群种质为核心, 将群体Pob21、Pob49、Pob501与A群种质, Pob32与B群种质, Pob43、La Posta与D群的四平头种质构建复合种质并进行改良, 逐步拓宽我国主要种质类群的遗传基础。     

不同种植密度和施氮量对几个玉米新品种生长发育及产量的影响

[目的]研究不同种植密度和施氮量对几个玉米(Zea mays L.)新品种生长发育及产量的影响,以找到其最佳种植密度和施氮量。[方法]通过3因素随机区组排列试验,建立了玉米新品种云瑞6号、云瑞8号、云瑞88号和楚单11号与种植密度、施肥量的数学模型。[结果]云瑞6号的最佳氮肥施用量为900 kg/hm2,采用普通施肥方法;最佳种植密度为6.75万株/hm2。云瑞8号的最佳氮肥施用量为600 kg/hm2,采用普通施肥方法;最佳种植密度为6.75万株/hm2。云瑞88号的最佳氮肥施用量为900 kg/hm2,采用时空施肥方法;最佳种植密度为5.25万株/hm2。楚单11号的最佳氮肥施用量为600 kg/hm2,采用时空施肥方法;最佳种植密度为5.25万株/hm2。[结论]该研究可为云瑞6号、云瑞8号、云瑞88和楚单11号在云南省楚雄地区的推广提供科学依据。     

沿淮地区中稻品种适应性和丰产性研究

[目的]研究沿淮地区中稻品种的适应性和丰产性,筛选适宜的中稻品种。[方法]参试品种共20个,分别是丰两优香1号、金优527、淮两优527、D优202、丰两优1号、D优527、Ⅱ优7954、Y两优1号、Q优6号、两优培九、扬两优6号、丰两优6号、徽两优6号、Ⅱ优602、新两优6号、新两优6380、内两优6号、Ⅱ优航1号、珞优8号、两优1128。品种随机排列,2次重复,栽插规格:30.0 cm×14.7 cm。[结果]徽两优6号、D优527和Ⅱ优7954水稻品种的综合性状较好,适合在沿淮地区推广种植。[结论]该研究可为沿淮地区水稻品种选择提供科学指导。     

植物资源学的教学实践与思考

从教材选用、教学内容安排、多媒体教学、互动教学以及本科生创新能力的培养探索等方面,阐述了植物资源学课程的教学实践情况,以期为提高植物资源学课程的教学质量提供借鉴。