高粱数量性状的多元遗传分析

Multivariate Genetic Analyses of Quantitative Characters in Sorghum

用多元遗传统计分析方法分析了高粱 18个性状间的遗传关系。结果表明 ,多数性状都与穗粒重呈显著和极显著表型相关。千粒重与旗叶宽相关极显著 ,穗粒数与穗径、穗柄径、茎粗、一级枝梗数、二级枝梗数和旗叶宽都极显著相关。遗传相关与表型相关的方向趋势一致 ,前者一般大于后者。 18个性状分别载荷在 4个主因子上 ,第一主因子为穗部因子 ,包括 8个与穗部结构有关的性状 ;第二因子为生长因子 ,包括生育期、茎粗及有关的 6个性状 ;第三因子为旗叶因子 ,包括旗叶的 3个性状 ;第四因子为穗长因子 ,只有穗长一个性状。聚类分析把 18个数量性状分成三大类 ,第三类又可进一步细分为两个亚类 ,聚类结果与因子分析完全一致。性状间的这种相关关系反映了数量性状遗传的“一因多效”和“多因共效”特性及相关性状间的协同变异趋势。

Statistical method of multivariate genetic analysis were used to study relationships among 18 sorghum characters.The result showed that phenotypic coeffecients of correlation of seed weight/head with most of other characters,1,000 seed weight with flag leaf width,seeds/head with diameters of head,peduncle and stalk,seeds/head with primary and secondary branches in head,were significant at 5% or 1% level.The genetic coefficients of correlation between characters demonstrated the same trends as the phenotypic ones did,but were generally lager than the latter.Four factors(Fs) were loaded with all the 18 characters through principle component analysis and factor analysis,F 1,called head factor,with 8 characters related mostly to head structure,F 2,called growth factor,with 6 characters related to days from seedling emergence to heading,flowering and maturing,and stalk diameter,F 3,called flag leaf factor with 3 characters related to flag leaf,and F 4 with only one character,head length,called head length factor.By cluster analysis 18 characters were clustered into 3 main groups(G 1,G 2 and G 3),and group 3(G 3) could be further divided into 2 sub groups(G 3-1 ,G 3-2 ),each group having the same characters as those of Fs loaded.The results of cluster analysis and factor analysis were completely the same.The relationships among the quantitative characters studied reflected the properties of 'one factor with more effect and multi factor with the same effect' and the coordinated variations in correlated characters.