四倍

The results showed that the best effect of autotetraploid was obtained with 2.0 gL-1 colchicine solution for 6 times, and the frequency was 4.5%.

结果表明：经2.0 gL^(-1)秋水仙素处理6次获得同源四倍体的效果最佳，四倍体诱导率达到4.5%。

All these contributed to the genetic selection and improvement in rice breeding. As mentioned above, the results are not only helpful to promote the process ofrice improvement, but also to confirm the basic for further study of autotetraploid rice.

上述产量、品质性状及遗传差异分析的结果，不仅有利于加快同源四倍体水稻的遗传改良进程，而且为进一步研究、利用同源四倍体水稻奠定了初步基础。

In the crosses of the autotetraploidy rices used as the females, some seeds could be got, but more seeds were obtained in these crosses by the special treatment that the DH solution was put into the caryopses before the pollination.

在以同源四倍体水稻为杂交母本的杂交组合中，可以获得一些实粒种子，但是，如果在授粉前利用DH溶液对同源四倍体水稻的去雄颖花进行处理后再授狼尾草的花粉粒则能获得更多的实粒种子。

We could get a better induction effect when we treated at the inflorescence out 1/4,or the another co- lor changing from light green to green-yellow color .It was just the period chromosome changed from bouquet stage to diakinesis stage.

在秋水仙素诱导小报春体细胞的研究中：以0.05g L~(-1)浓度的秋水仙素浸泡萌动种子48h得到1株四倍体；组培诱导中，以秋水仙素加入培养基中，秋水仙素浓度为0.1gL~(-1)处理一周获得2株四倍体小报春。

If 〓mRNA positive expression, its DNA heteroploid type display as triploid or hypodiploidy, if 〓mRNA negative expression, its DNA heteroploid type display as hyperdiploidy、tetraploid or Bistem line. These from one flank demonstrate the role of 〓 gene suppress the proliferation of malignant tumor

表达阳性者，其DNA异倍体主要表现为三倍体或低二倍体，〓表达阴性者，其DNA异倍体主要表现为高倍体、四倍体和双干系，从一个侧面显示出〓基因的抑制恶性肿瘤细胞增殖的作用。

However, analysis of DNA methylation level indicated that the total DNA methylation levels were not significantly different between diploid and autotetraploid. Autotriploid showed a trend of low DNA methylation level. It implied that the alterations of DNA methylation levels were not linear with the autopolyploidy level in watermelon.

有趣地是，二倍体与四倍体西瓜相比DNA甲基化水准却未发生大规模的调整，而三倍体西瓜显示出较为明显的低DNA甲基化水准趋势，表明西瓜同源多倍化过程中其基因组DNA甲基化水准变化与其倍性不成线性关系。

The genetic analysis and improvement of characters, such as tuber processing quality traits and yield components which tend to be quantitatively inherited, are far more difficult than those at diploid potato. Reviewing the earlier studies indicated that a few systematic investigations on genetics of important traits in potato were untaken and most focused on estimates of combing ability for agronomic traits due to limited materials and methodologies available.

利用二倍体材料简化了遗传分离比例、可应用现有的二倍体遗传模型进行遗传分析并更有效的挖掘和利用二倍体资源中的优异基因，进而通过倍性育种及遗传工程育种将有利性状转育到四倍体普通栽培品种。

Most primers amplified same bands in diploids, tetraploids and hexaploids. It suggest that D and AB genomes have high homology and D genomes be successfully transferred from diploid to hexaploid.

从供试的绝大多数引物均能在不同倍性小麦中扩增出相同的条带证明了D染色体组和AB染色体组间存在着很高的同源性以及利用二倍体和四倍体小麦杂交人工合成六倍体小麦的真实性。

The result showed that: 1 Gill epithelium nucleus major-axis size, hemolymph nucleus diameter in the connective tissue of mantle and labial palps were significantly (P＜0.001) larger in triploids than in diploids, no significantly differences were found in rectum epithelium height between diploids and triploids.

另外，通过组织切片、扫描电镜和透射电镜等方法比较了二倍体和三倍体太平洋牡蛎的几种组织器官的细胞大小、鳃的表面结构和鳃的超微结构，二倍体和四倍体精子的超微结构上的差异，旨在为更好的发展多倍体育种技术、探索多倍体的快速生长机制提供理论依据。

Finally both SNR and slope of modulation transfer spectra of I2 with different absorption length were compared experimentally while I2 cell temperature was held at -15 ℃. The results of comparison showed that modulation transfer spectra was optimal at three-pass (120 cm).

实验上比较了碘池温度为-15 ℃时一倍程(40 cm)，二倍程(80 cm)，三倍程(120 cm)和四倍程(160 cm)的光谱信号信噪比和谱线中心斜率，得到三倍程时信号信噪比和谱线中心斜率为最大，估算得到相应的激光稳频精度为9×10-14(1 s积分时间)。

It seems likely that Kraft will return with a better offer.

看起来卡夫要重新考虑一个更好的出价了。

But he'd rather burn off my feelers and watch me squirm.

可他却放任那个家伙对我为所欲为！