二倍

In the self-bred progenies of autopolyploid,we found that a very few chimaeraexist in the cells of root tips,but most of them had no change in ploidy. We also found13 diploid plants in the experimental plot (ratio is 0.46%) and can be divided into 4categories.

在部分同源多倍体株系的自交结实后代中，随机取样进行根尖染色体检查，结果表明多倍株系体的自交结实后代倍性没有变化，但发现有个别细胞为不同倍性的嵌合体；田间观察到分离出来的极少数正常二倍体，占0.46％，按照形态特征可以分成四个不同的类型。

Tetraploid embryos could be produced by electrofusion at the stage of two-cell embryos, which could develop to blastocysts followed by fusion of cyto-plasm and nucleus and cleavage in vitro. During the fusion of cytoplasm, the DNA methylation levels of the fused embryos are as high as these of two-cell diploid embryos in vivo Then the embryos are rapidly demethylated when the nucleus begin to fuse, resulting in the lowest DNA methylation levels when the nucleus are fused completely. After that, the DNA methy-lation levels of the fused embryos are gradually increased until the morula stage. However, whereas an asymmetric distribu-tion of DNA methylation is established in vivo-derived blastocysts with a higher methylation level in the inner cell mass than that in the trophectoderm, we can not detect the asymmetric distribution in most in vitro-derived tetraploid blastocysts.

结果表明：利用电融合方法制备的小鼠四倍体胚胎在体外培养体系中经历细胞质融合、细胞核融合及细胞继续分裂发育直到囊胚期的过程，在细胞质融合的时候胚胎卵裂球同体内体外培养二倍体胚胎一样，呈现高度甲基化状态；在细胞核开始融合的时候，甲基化水平急速下降，在细胞核完全融合的时候甲基化水平达到最低点；随着胚胎继续分裂，胚胎甲基化水平逐渐增加，在桑葚胚期甲基化水平最高；但是囊胚期四倍体胚胎内细胞团同滋养层细胞甲基化荧光信号没有差别，这与体内体外培养二倍体囊胚内细胞团细胞甲基化荧光强度高于滋养层细胞甲基化荧光强度不同。

Tetraploid embryos could be produced by electrofusion at the stage of two-cell embryos, which could develop to blastcysts fellowed by fusion of cytoplasm and nucleus and cleavage in vitro.After fusion of cytoplasm, the DNA methylation levels of the fused embryos was very high as well as two-cell diploid embryos in vivo.Then the embryos was rapiddly demethylated when the nucleus begin to fuse, resulting the lowest DNA methylation levels when the nucleus fused completely.After that, the DNA methylation levels of fused embryos were gradually increased until the blastocysts stage.However, whereas an asymmetric distribution of DNA methylation was established in an vivo-derived blastocysts with a higher methylation level in the inner cell mass than in the trophectoderm, in most vitro-derived tetraploid blastocysts, we can not detect the asymmetric distribution.

结果表明：利用电融合方法制备的小鼠四倍体胚胎在体外培养体系中经历细胞质融合、细胞核融合及细胞继续分裂发育直到囊胚期的过程，在细胞质融合的时候胚胎卵裂球同体内体外培养二倍体胚胎一样，呈现高度甲基化状态；在细胞核开始融合的时候，甲基化水平急速下降，在细胞核完全融合的时候甲基化水平达到最低点；随着胚胎继续分裂，胚胎甲基化水平逐渐增加，在囊胚期甲基化水平最高；但是囊胚期四倍体胚胎内细胞团同滋养层细胞甲基化荧光信号没有差别，这与体内体外培养二倍体囊胚内细胞团细胞甲基化荧光强度高于滋养层细胞甲基化荧光强度不同。

F〓 of transgenic allotetraploid fish containing"all-fish"transgene——pCAgcGHc was obtained respectively by inbreeding and gynogenesis. Positive rate of pCAgcGHc detected by PCR was 90％ in F〓 of transgenic allotetraploid fish produced by inbreeding, while most F〓 of transgenic allotetraploid fish produced by gynogenesis showed diploidy measured by flow cytometer. The results above imply that developing the pure line of transgenic allotetraploid fish through inbreeding is feasible, but the operation should be modified if gynogenesis is introduced.

采用近交和雌核发育方法培育出转pCAgcGHc基因异源四倍体鲫鲤F〓代，通过PCR检测，外源基因pCAgcGHc在近交转pCAgcGHc基因异源四倍体鲫鲤F〓中的整合率为90％，而流式细胞技术检测雌核发育转pCAgcGHc基因异源四倍体鲫鲤F〓的倍性多为二倍体，说明通过近交筛选转基因异源四倍体鲫鲤纯系的方法是可行的，但是通过雌核发育来筛选转基因异源四倍体鲫鲤纯系还要就方法上进一步的改进。

Tetraploid organisms may arise by the fusion of two diploid gametes that have resulted from the nondisjunction of chromosomes at meiosis, or by nondisjunction of the chromoosomes during the mitotic division of a zygote.

四倍体的产生可能是由于两个二倍体配子发生融合，这种二倍体配子又是在减数分裂中染色体不发生分离而形成。四倍体也可能因为受精卵进行有丝分裂时染色单体未发生分离而形成。

Diploid, triploid, tetraploid, pentaploid and hexaploid hybrid plants have been recovered from protoplast fusion, among which the tetraploid ones accounted for almost90%.

这些体细胞杂种有二倍体、倍体、倍体、倍体和六倍体，但主要是四倍体。

Results showed that the PMC meiosis of autotetraploid was similar to the diploid except some particularities. In metaphase Ⅰ, multivalent, quadrivalent, trivalent, bivalent and univalent were observed and some of the chromosomes were found not to rank on the metaphase plate and so did in metaphase Ⅱ cells. In anaphase Ⅰ and anaphase Ⅱ cells, there were lagging chromosomes, chromosome bridge and fragment. During anaphase Ⅱ and telophase Ⅱ, chromosome segregation was not synchronous or equal. At tetrad stage, dyad, triad, tetrad with micronucleus and polyad appeared.

结果表明，同源四倍体花粉母细胞减数分裂过程与二倍体相比，中期Ⅰ染色体构型复杂，有多价体、四价体、三价体、二价体和单价体；中期Ⅰ及中期Ⅱ有部分染色体没有排列在赤道板上；后期Ⅰ及后期Ⅱ出现落后染色体、染色体桥及断片；后期Ⅱ和末期Ⅱ有染色体不同步分离及不等分裂的现象；四分体时期还出现二分体、三分体、含微核的异常四分体及多分体。

However, the use of Aegliops tauschii in improvement of wheat yield trait has not been reported. In this study, T.durum-Ae.Squarrosa amphidiploids was crossed with common wheat PH85-16, then backcrossed with PH85-16. The variation characteristic of the main yield traits of BC1F1 and BC1F2 were analyzed. Then, QTLs affecting yield traits were detected by 130 SSR primer pairs of D genome in BC_1F_1 and BC_1F_2.The result showed chromosomes in D genome from Aegliops tauschii affected yield trait of wheat significantly.

本研究以二倍体小麦粗山羊草与四倍体硬粒小麦合成的双二倍体Am6为亲本，与普通小麦PH85-16 进行杂交，再用PH85-16 进行回交，对获得的回交后代进行了主要产量性状调查，利用位于小麦D 基组的SSR 分子标记进行了分子标记分析，对来自粗山羊草与产量性状相关的数量性状位点进行定位，探讨粗山羊草对小麦产量性状的影响。

There are three parts included. The first part is the prepositive-amplifier, it gets broadband high gain and flat frequency response. The second part is the U band quadrupler, which composed of two doublers using a PHEMT chip HMMC-5040, a Schottky diode of DMK-2790, a HMMC-5040 amplifier, and a fin-line transitional stage. Maximum output power higher than 60mW is obtained in V band. The third part is a 2nd harmonic gunn oscillator injection locked by the Fundamental Wave,which get about 2GHz locked bandwidth in W band.

电路主要由三部分组成，第一部分为采用HMMC-5618设计的前置放大器，实现了宽带高增益和平坦的频率响应；第二部分为设计的主体，由HMMC-5040设计的二倍频器、DMK-2790设计的二倍频器、HMMC-5040设计的放大器及鳍线过渡段组成的U波段四倍频器，在U波段实现了最高60mW以上的输出功率；第三部分为基波注入锁定谐波Gunn振荡器，在W波段实现了近2GHz锁定带宽。

In grain-filling stage, the qP values of evolutionary wheats decreased under water stress, while Shan253 and Changwu134 hadn't decreased, indicated that the effect of water stress on the re-oxidation in Q-A of modern wheat was slight, while before this stage, the electron transport from PSⅡto QA restrained by water stress was main factor of photosynthesis non-stomata limitation to modern wheat; The qNP values of hexaploid were higher than diploid and tetraploid wheat, indicated that the ability of using light energy

随小麦由二倍体向四倍体、六倍体及现代小麦进化，表观电子传递速率有增大趋势，其受水分胁迫影响的程度在花前期有加剧趋势，花前期栽培一粒、栽培二粒、普通小麦、陕253和长武134这五种小麦在水分胁迫下表观量子产额的降幅分别为5%、7.47%、14.29%、33.3%和53.49%，光饱和Pn的降幅分别为8.8%、26.14%、23.25%、44.22%和51.29%，光饱和点整体上也是下降的，且这三个指标的降幅随进化程度提高有增大趋势，表明小麦在进化过程中能量转换系统受水分胁迫影响的程度加剧；而在水分胁迫下，小麦的羧化效率和RuBP再生速率也均下降，下降的程

The labia have now been sutured together almost completely.The drains and the Foley catheter come out at the top.

此刻阴唇已经几乎完全的缝在一起了，排除多余淤血体液的管子和Foley导管从顶端冒出来。

To get the business done, I suggest we split the difference in price.

为了做成这笔生意，我建议我们在价格上大家各让一半。