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为探讨偏凸山羊草-柱穗山羊草双二倍体SDAU18在小麦遗传改良中的利用价值,以SDAU18和普通小麦品种烟农15及其9个杂种世代为材料,分析不同自交和回交世代染色体和性状分离的特点。结果表明,随自交世代和以烟农15为轮回亲本回交世代的增加,染色体数目逐渐减少,回交比自交能使后代的染色体数目更快趋近普通小麦的42条,至F5和BC3F1代,染色体数目为42的植株已分别达93.9%和92.0%。与自交世代相比,回交后代减数第一分裂中期的花粉母细胞的染色体构型较为简单,回交次数过多不利于外源染色体与普通小麦染色体发生重组,一般应以回交2~3次为宜;随自交和回交世代的增进,杂种的育性提高,至F3和BC2F1代育性基本稳定。在不同杂种世代可分离出具有矮秆、大穗、大粒、对白粉病、条锈病免疫或高抗及外观品质优良的变异类型,以F3和BC1F1代的变异类型最丰富。
In order to investigate the value of SDAU18, a diploid Aegilops colchicus-Leucaena leucocephalus diploid, for genetic improvement in wheat, SDAU18 and common wheat cultivar Yannong 15 and its 9 hybrids were used as materials to analyze the genetic diversity of different selfing and backcross generations Chromosome and trait separation characteristics. The results showed that the number of chromosomes decreased with the increase of backcross generation in the cross between selfing and reincarnation of tobacco farmers 15, and the number of chromosomes of progeny in backcross was faster than that of selfing, reaching 42 of common wheat to F5 and BC3F1 Plants with chromosome number 42 had 93.9% and 92.0%, respectively. Compared with the selfing generation, the chromosome configuration of the pollen mother cells with the first division of the next generation backcrossing is relatively simple, and the number of backcrosses is not conducive to the recombination of exogenous chromosomes and common wheat chromosomes. ~ 3 times. With the improvement of selfing and backcross generation, the fertility of hybrids increased, and the fertility of F3 and BC2F1 was basically stable. In the different hybrid generations can be isolated with dwarf, big spike, large grain, powdery mildew, stripe rust immunity or high resistance and appearance quality of the variation types to F3 and BC1F1 generation of the most abundant types of variation.