杂种

Subclones of the hybrid 741 took on a high insect-resistant identity to the larvae of leaf pests such as Clostera anachoreta Fabricius, Lymantria dispar Linnacus, Hyphantria cunea Drury ect., and the mean death rate of the grubs were all above the 85%, furthermore, the grubs' growth which survived could be restrained and the growth rate was reduced so that they couldn't tie cocoons as the usual.

项目简介：转双抗虫基因741杨是将部分改造BtCryIAc 基因与慈菇蛋白酶抑制剂基因，通过农杆菌介导法转化了优良白杨杂种741杨，并获得了一批具有高抗虫性无性系，对舞毒蛾和杨扇舟蛾，美国白蛾等鳞翅目幼虫死亡率达85%以上，并能抑制存活幼虫的发育，使其不能正常化蛹。

The chromosome behavior of the meio sis at MI of the hybrids between every 2 of 5 OTE types and between vevry one of the hybrids with Tr.aestivum was observed.

通过八倍体小偃麦与普通小麦杂交，八倍体小偃麦相互间杂交，观察了杂种F1花粉母细胞减数分裂行为。

So it is very necessary to study variances of Chinese Meretrix meretrix germplasm resources and their molecular genetic bases for their lasting utilization,sustained and healthy development of aquaculture industry. In this study, the genetic bases and their variances of representative populations of Meretrix clam were investigated through phenotypic traits and on the molecular level by quantitative genetic methods and molecular marker analysis technique.

本研究从表观性状和分子水平上探测我国文蛤种质资源的遗传基础和变异水平，旨在深入了解我国文蛤的种质状况并为其保护和可持续利用提供依据；在此基础上，通过杂交选择育种实践，分析和探讨文蛤由此获得杂种优势水平，为养殖文蛤的遗传改良和新品种培育提供理论指导。

Amblycephala is composed of 13 metacentric chromosome pairs, 9 submetacentric chro-mosome pairs and 2 subtelocentric chromosome pairs, which can be expressed as 26m + 18sm+ 4st.

随着鱼类杂交育种研究的深人，染色体的组型研究也逐渐应用于预测杂交成功与否、杂种能否正常生育等方面。

Accordingly we start from the definition of heterosisH=F1-MP,where H is heterosis, F1 is the first generation offspring, MP is the mean of the parents or midparent, and from the use of a binomial random variable and its extention to the multinomial case derive the basic relations of heterosis with its components.

另一在原文中未加说明的原因是，用配合力概念需要无穷多个品系才能和遗传力的结果相比较，仅此一点就把配合力的作用排斥掉了。文中的主题是杂种优势老大难题可以用笛卡尔的推理方法来解决。

The equations of heterosis areV(subscript F1)=(l/2)Na^2+(l/4)Nd^2+Vsubscript I(F1additive dominance F1 epistasisV=(1/2)Na^2+(l/2)V1,additive parental epistasisV=(1/4)Nd^2+Vsubscript I(F1+(1/2)Vl,dominance F1 epistasis parental epistasis.where N is number of genes controlling a trait,α=P(subscript i-P/2, d is deviation from midparent, while the variance components are all indicated by their names under the repective terms.

由一个二项分布随机变数及其推广至多项分布推导出杂种优势的公式：V(下标 F1)=Na^2/2+Nd^2/4+V下标(F1加性显性 F1上位V＝Na^2/2+V/2加性亲代上位V＝Nd^2/4+V下标(F1+V/2显性 F1上位亲代上位在此N=控制性状的基因数，α=p(下标 i-P/2， d=离中亲的偏差，而各方差则如方程底部所列。

Somaclonal variations analysis on mixoploid hybrid plant BI-1 showed that percentage of cells with 2n=25, 26 decreased and percentage of cells with 2n=29 ascended.Chromosome segments of I.

并对混倍体杂种BI-1的无性系变异进行了分析，发现染色体数目为25、26的细胞比例呈明显下降趋势，而染色体数为29的细胞比例明显上升，其他染色体数目的细胞比例处于动态变化之中。

By chromosome counting, the detected hybrids were mixoploid.

通过染色体计数，发现所检测杂种为混倍体，同一植株的细胞有多种染色体数目构成。

In order to reveal clearly the genetic character of the dwarfing polish wheat, artificial crossing, cytological and morphological studies were carried out in present study. In addition, the chromosomal location of dwarfing and long glume character of dwarfing polish wheat was studied by means of Langdon monosomic analysis.

本试验：(1)通过矮秆波兰小麦与8个来源不同或染色体组组成不同的小麦属材料杂交，对杂种F_1进行细胞遗传学分析；(2)采用单体分析法，对矮秆波兰小麦的矮秆、长颖基因进行了基因定位。

We can get nonmalignant hybrid cells.

我们可以获得非恶性的杂种细胞。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。