杂种优势

The average heterosis of the grain yield per plant is 75. 79%, 57. 67% and 12. 55% in the hybrids of the common wheat with spelt wheat, club wheat and itself respectively. the heterosis degree of the interspecific hybrid was greater than that of intervarietal hybrid.

普通小麦与斯卑尔脱小麦的种间杂种每株产量的平均杂种优势为75.79%，普通小麦与密穗小麦的种间杂种每株产量的平均杂种优势为57.67%，普通小麦品种间杂种每株产量的平均杂种优势为12.55%，种间杂种优势大于品种间杂种优势。

The average heterosis of spike number per plant and 1 000-grain-weight were high and obviously related to yield heterosis at 0. 01 and 0. 05 level, respectively; the average yield heterosis of F1 hybrids between common wheat and club wheat was 77. 19%(ranged from-2. 18% to 143. 42%), the average heterosis of spike number per plant and spike grain number were high and both was also obviously related to yield heterosis at 0. 01 level.

结果发现：小麦种间杂种在产量上具有明显的杂种优势，其中斯卑尔脱小麦与普通小麦所配的30个种间杂交组合产量杂种优势平均为109.24%(43.14%～187.96%)，单株穗数及千粒重平均优势较大且与产量优势的相关分别达极显著水平和显著水平；密穗小麦与普通小麦所配的30个种间杂种的杂种优势为77.19%(-2.18%～143.42%)，单株穗数和主穗粒数优势较大且与产量优势的相关均达极显著水平。

The SCA effect was important in the heterosis of the spike number per plant of the intervarietal hybrid, the SCA and GCA were both important in the heterosis of the grain number of main spike of the intervarietal hybrid; the SCA effect played an major role in the heterosis of the spike number per plant of the interspecific crosses of the common wheat and club wheat, the SCA effect played an major role in the heterosis of the 1000-grain weight of the interspecific crosses of the common wheat and spelt wheat.

普通小麦品种间杂种每株穗数杂种优势中，特殊配合力所代表的非加性遗传效应起了主要作用，而主穗粒数杂种优势中一般配合力、特殊配合力所代表的加性、非加性遗传效应所起的作用相当；普通小麦与密穗小麦种间杂种主穗粒数杂种优势中特殊配合力所代表的非加性遗传效应起了主要作用；普通小麦与斯卑尔脱小麦间杂种千粒重杂种优势中特殊配合力所代表的非加性遗传效应起了主要作用。

Maize germplasm gets more and more mixed. To make full use of heterosis, it is very important for maize breeders to distinguish heterotic groups and to design heterotic patterns.

玉米种质日趋复杂，对现有种质资源进行杂种优势群的划分，构建杂种优势模式的基本框架，将对进一步提高杂种优势利用水平，对当前和今后的玉米育种工作有重要的指导意义。

But to make good use of them, their genetic characteristics and germplasm relationship with Chinese inbred lines representing different heterotic groups should be studied.

本研究采用传统的配合力和杂种优势分析与现代的SSR分子标记技术相结合的方法，探讨引进南斯拉夫玉米自交系与我国不同优势类群骨干自交系的配合力、杂种优势、遗传距离和杂合性，为引进自交系的高效合理利用提供理论依据；并通过各项遗传指标与F1产量的相关分析，探讨各项指标预测杂种优势的可行性和效果。

In this study, through the traditional methods, analysis of combining ability and heterosis, and modern SSR marker technique, the combining ability, heterosis, genetic distance and heterozygosity between introduced Yugoslavia inbreds and important lines representing different heterotic groups in our country were studied, which will greatly influence to make full use of those indroduced lines.

本研究采用传统的配合力和杂种优势分析与现代的SSR分子标记技术相结合的方法，探讨引进南斯拉夫玉米自交系与我国不同优势类群骨干自交系的配合力、杂种优势、遗传距离和杂合性，为引进自交系的高效合理利用提供理论依据；并通过各项遗传指标与F1产量的相关分析，探讨各项指标预测杂种优势的可行性和效果。

The higher percentage of cross-fertilized kernel specifically expressed pattern was observed in highly heterotic hybrid, after comparison of gene differential expression between cross-fertilized and self-fertilized kernels during the early development of seed in wheat and maize, respectively. This indicated that there may be have common molecular mechanism for heterosis in different crops.

本文对玉米和小麦在种子发育前期杂交和自交间基因差异表达进行了比较，发现杂交特异表达类型与杂种优势均存在一定的正向关系，说明不同作物杂种优势形成在分子水平上具有共同点，即相同表达模式的基因或基因群在不同作物杂种优势形成中发挥一致的作用。

Stuber et al.(1992) considered the overdominance is the major genetic basis of heterosis in maize; Xiao et al.(1995) suggested the dominance is the major molecular mechanism of heterosis in rice. Subsequently, Yu et al.(1997) and Hua et al.(2003) demonstrated the epistasis made the siginificant contribution to heterosis in rice.

Stuber等认为，超显性是玉米杂种优势形成的主要原因；Xiao等(1995)认为显性作用是水稻杂种优势形成的遗传基础，Yu等(1997)和Hua等(2003)认为上位性在杂种优势形成过程中起重要作用。

He not only is our country hybrid rice research founder, also is the our country hybrid rice research chief designer and the most main leaders in a scholarly field. In 1986 he proposed the hybrid rice breeding from three is the law to two is the law to one is the law and uses three development phases from the variety to the subspecies to 远缘杂种 the superiority the strategic tentative plan, this tentative plan has become the domestic and foreign recognitions hybrid rice breeding the guiding ideology.

他不仅是我国杂交水稻研究的开创者，也是我国杂交水稻研究的总设计师和最主要的学术带头人。1986年他提出杂交水稻育种由三系法到两系法到一系法和从品种间到亚种间到远缘杂种优势利用三个发展阶段的战略设想，这一设想已成为国内外公认杂交水稻育种的指导思想。1987年两系法杂交水稻技术被列为国家&863&计划的重点课题。

Major difference of gene expression occurred in the qualitative level, especially cross-fertilized kernel specifically expressed pattern.

对三个不同优势的小麦杂交种子和自交种子及其正反杂交种与其双亲种子发育前期基因表达研究表明，杂交种子和自交种子之间存在明显的基因表达差异，且以质的特异表达为主；不同优势的正反杂交当代种子与亲本间基因表达发生了显著的改变，进一步分析发现单亲表达与杂种优势存在一定的正向关系，而杂种沉默表达与杂种优势存在一定的负向关系。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。