杂种的

The study on kenaf sterile line may be a base for the utilization of heterosis. In this paper, the research progress of kenaf sterile line was summarized based on the level of morphology, cell and molecule. We also discussed some related technological problems of heterosis.

红麻雄性不育系的研究是红麻杂种优势利用的重要基础，本文从个体形态、细胞和分子生物学层面上综述红麻雄性不育系的研究进展，并讨论和展望了红麻雄性不育与杂种优势利用的关键科学技术问题。

Chromosome pairing behavior in meiosis of the hybrid F1 was carried out. Results showed that in an average , 1.25 rod bivalents were observed in one PMC, meiotic configuration was 2n=14=11.49Ⅰ+1.25Ⅱ(Xta=1.25) and most of PMCs possessed 1～5 bivalens, indicating that the relatively high homeology was detected between the D genome of Ae.tauschii and the V genome of D.villosum. The morphological differences between F1 hybrids and their parents were significant. F1 plants were highly self-sterile, but partially self-fertile after treated by chromosome doubling technique.

对杂种F1花粉母细胞减数分裂中期Ⅰ染色体配对行为进行观察发现，"节节麦×簇毛麦"杂种F1平均每PMC有1.25个棒状二价体，染色体的平均构型为2n=14=11.49Ⅰ+1.25Ⅱ(Xta=1.25)，大部分被观察的细胞出现1～5个二价体，表明节节麦D染色体与簇毛麦V染色体间具有相对较高的部分同源配对， D和V染色体之间存在一定的部分同源性。F1植株高度自交不育，经染色体加倍处理后能够自交结实。

Sex-linkage model reveals that hybrid vigor rate is a complex function related withdominance of gene effects of hybrid,additivity and dominance of the parent genes,and ef-fects of sex-linked genes.Owing to interaction of genes and environment,hybrid vigor ratevaries with seasons.

性连锁模型揭示，杂种优势率是一个与杂交种的显性效应、亲本的加性效应、显性效应、性连锁效应等基因效应有关的复杂函数，由于基因与环境的互作，造成杂种优势率在不同季节表现不一致。

Based on the Liriodendron interspecies hybridization study by professor Ye Peizhong,according to the satisfying and exact mating system and field design,the reciprocal cross with extensive genetic background of Liriodendron tulipifera Linn., the backcross and F 1 crossing which had never been made, and the genetic analysis of heterosis of the hybrid tulip tree were carried out.

在叶培忠先生的鹅掌楸属种间杂交育种研究基础上按遗传设计与环境设计开展了扩大北美鹅掌楸遗传基础条件下的正反交以及前人从未做过的回交和F1 间杂交，并进行了杂种马褂木杂种优势的遗传分析。

Mayr also introduced the biological species concept that defined a species as a group of interbreeding or potentially interbreeding populations that were reproductively isolated from all other populations.

迈尔还提出了生物学的物种概念，定义物种为一个杂种繁殖的群体（或潜在地杂种繁殖的群体），与所有其它的种群在生殖上隔离。

Dentatus male (H1) were found to be viable, while the reciprocal hybrids from P. dentatus female and P. olivaceus male (H2) were completely inviable. All the H2 individuals showed morphological deformities and died before first feeding.

褐牙鲆和夏牙鲆正反交的活力是不对称的，褐牙鲆♀×夏牙鲆♂的正交杂种活力正常，能够正常存活、生长和发育，而反交夏牙鲆♀×褐牙鲆♂的杂种体态畸形，孵出后不久死亡。

Is one of the most important vegetable crops, it shows remarkable heterosis, producing hybrid seed using Cytoplasmic Male Sterile line as female parent is a very important way to utilize the heterosis in radish.

是一种非常重要的蔬菜作物，其具有明显的杂种优势，以细胞质雄性不育系为母本，实行三系配套的制种方式是萝卜杂种优势利用的重要途径。

Dogs most at risk were Labradors, Beagles and cross-breeds（10） such as Labradoodles —— a mixture of a Labrador and a Poodle（11）—— with household moggies（12） more at risk than other types of cats.

最容易患病的狗狗是拉布拉多猎犬、毕尔格猎犬和如拉布拉多和狮子狗所生的杂种小狗，宠物猫中最容易患病的是杂种小猫。

With some 40,000 mongrels born in Denmark every year, a mass cull of mutts would reach alarming proportions.

随着丹麦每年40，000只杂种狗的诞生，大规模对杂种狗的宰杀将会达到惊人的地步。

There was significant difference of fibre length of willow nursery stock and it exists both among different hybrids and clones.

柳树的纤维长与纤维素含量在苗期即有显著差异，其纤维长的遗传变异，无论是在杂种间，还是在杂种内无性系间都是显著的。

I can not make it blossom and suits me

我不能让树为我开花

When temperatures are above approximately 80 °C discolouration of the raceways or rolling elements is a frequent feature.

当温度高于 80 °C 左右时，滚道或滚动元件褪色是很常见的特征。