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以优良玉米(Zea maysL.)自交系抗感杂交组合(R15×掖478)的F2群体为材料,构建了239个分子标记(包括151个SSR标记和88个AFLP标记)的玉米分子连锁图,覆盖全基因组3 463.5 cM,相邻标记间的平均间距为14.5 cM。在239个标记中,16个SSR标记和9个AFLP标记表现偏分离(P<0.05)。在4条不同的染色体上发现5个偏分离的热点区域,其中3个与已经定位的配子体基因的位置相近,表明配子体基因可能是导致偏分离的部分原因。还发现SDR2和SDR7可能是2个偏分离的新热点区域。进一步讨论了引起偏分离的原因,以及偏分离标记对估算遗传距离的影响。当存在单个的配子体基因时,遗传距离的估算不受偏分离的影响;当存在2个或者2个以上配子体基因时,对遗传距离的估算有偏差。
A total of 239 molecular markers (including 151 SSR markers and 88 AFLP markers) were constructed from F2 populations of Zea mays L. inbred lines (R15 × tuck 478) Covering 3 463.5 cM of the whole genome with an average spacing of 14.5 cM between adjacent markers. Of the 239 markers, 16 SSR markers and 9 AFLP markers showed partial segregation (P <0.05). Five hot spots of partial segregation were found on four different chromosomes, of which three were located close to those of the already-located gametophyte genes, suggesting that gametocyte genes may be responsible for partial segregation. It is also found that SDR2 and SDR7 may be two new hotspot areas that are partially separated. Further discussing the causes of partial segregation and the effect of partial segregation markers on estimating genetic distance. When there is a single gametophyte gene, the estimation of the genetic distance is not affected by the partial segregation; when there are two or more gametophyte genes, the estimation of the genetic distance is biased.