柱花草遗传家系建立及遗传变异分析

Establishment of Stylosanthes Genetic Family and Analysis of Its Genetic Variability

以1979柱花草(S.guianensis TPRC1979)为母本、品45柱花草(S.guianensis TPRCR273)为父本杂交,F1杂种自交获得202株F2代分离群体,对此柱花草家系的形态学性状、农艺学性状及营养成分含量变化进行分析,以此探究该家系内各个性状的遗传特性及其遗传规律。结果表明:柱花草花色遗传可能由一对等位基因控制,黄花对白花为显性性状;F2代出现了亲本及F1没有的斜倚型,其中直立型87株(43.07%),斜倚型115株(56.93%);农艺学性状平均变异系数为20%,变异最大的是鲜重(46.19%)和干重(44.84%),变异系数最小的为叶长(8.31%);营养成分含量变异系数排前3位的为粗脂肪>钙>磷。F_2代群体的形态学性状、农艺学性状和营养成分含量的各个性状都有不同的变异,符合数量性状遗传特点,能为后续柱花草遗传图谱构建和QTL定位提供一定的基础。

Stylosanthesguianensis TPRC1979(female) and Stylosanthesguianensis TPRCR273(male) were crossed as parent lines. The hybrid F_1 was selfcrossed to produce 202 individuals of F_2 segregating population. The morphological characters, agronomic traits and nutrient content changes of this Stylosanthes genetic pedigree were analyzed in order to explore the genetic characteristics of the individual and inheritance law within its family. The results showed that the color of Stylosanthes may be controlled by a pair of main genetic alleles and yellow flower is the dominant trait to white flower. There were 87 plants with erect types(43.07%) and 115 plants with creeping types(56.93%). The creeping type in F2 generation was not appeared in parent and F1 generation plants; The average variation coefficient of agronomic traits was 20%, Fresh weight(46.19%) and dry weight(44.84%) were the main variation traits. The minimum coefficient of variation was leaf length(8.31%). The largest three coefficient of variation was Fat, Ca and P. Differences existing among the morphological characters, agronomic characters and nutrient content in F_2 population presented quantitative genetic character. This research provided a foundation for Stylosanthes subsequent map construction and QTL location.