高丹草是一年生禾本科新型饲用牧草,提高其饲草产量是高丹草育种的重要目标。以高粱314A×棕壳苏丹草的F2:3遗传作图群体的后代材料建立的重组自交系(Recombinant inbred line,RIL)群体为材料,对后代进行遗传变异和DNA多样性分析。结果表明:通过采用两种方法(性状和分子标记)进行同时选择,获得了9个高产的超亲重组后代。通过SSR标记分析RIL群体的DNA多样性,可知家系间存在较大的遗传变异,杂交重组产生的超亲高产种质分布在不同类群中。鉴定获得了2组SSR遗传距离接近0而且在主要农艺性状和产量等方面相似,只在抗性方面有差异的不同家系。农艺性状和抗性等鉴定试验筛选了4份性状优良的高丹草新种质并已有2份进入区域试验。
Sorghum-Sudan grass which is an annual forage grass in Gramineae have been bred for biomass promotion.The recombinant inbred line(RIL) populations were derived from the F2:3 genetic mapping population of Sorghum 314A×zongke Sudan grass.The breeding selection based on agronomic characters and DNA molecular marker statistical analysis was carried among the progenies of the RIL populations,and 9 recombinant breeding progenies were determined as heterobeltiosis with high yield.According to DNA diversity analysis of simple sequence of repeats(SSR) marker, the genetic varieties were abundant among the families, and the recombinant breeds of high yield were distributed among the different RIL populations. 2 family lines, which have similar agronomic characters and yield, and whose genetic distance nearly equal to zero, showed difference on arid tolerance;4 breeding lines were selected on agronomic characters and resistance in the field trials, and 2 breed lines were qualified for the regional testing.