早熟陆地棉亲本遗传距离与杂种优势的相关性分析

【目的】为早熟陆地棉杂交亲本选配及杂种优势预测提供参考信息。【方法】将12个早熟陆地棉品种初步划分成两组亲本,田间调查17个主要性状,并进行SSR分子标记检测,对基于表现型和基因型差异的遗传距离与F1代主要性状杂种优势的相关性进行分析。【结果】基于5个主成分因子得分两组亲本间的平均遗传距离为5.535,最大为9.097,最小为3.097;基于SSR扩增结果两组亲本间的平均遗传距离为4.186,最大为5.099,最小为2.646。36个组合F1代生育期、铃数、单铃重、衣分、绒长、籽棉产量和皮棉产量的平均中亲优势分别为0.367、-1.256、14.176、6.691、1.000、11.206和15.235,平均超亲优势分别为-0.966、-1.464、6.457、0.110、-2.500、7.561和10.816。基于性状主成分因子得分的遗传距离只与F1代衣分的中亲优势呈极显著正相关;基于SSR扩增结果的遗传距离与生育期的中亲优势、衣分和绒长的超亲优势呈显著负相关。【结论】早熟陆地棉的铃重和产量具有较强的杂种优势;衣分具有较强的中亲优势。亲本的遗传距离只与F1代个别性状的杂种优势具有显著相关,且与产量不是简单的线性关系。部分性状的杂种优势随遗传距离的增大而增大,但部分性状则减小。

Correlation Analysis of Genetic Distance and Heterosis of Early Maturing Upland Cotton Parent Line

【Objective】 The purpose of this paper is to provide useful information for selecting the cross parent and predicting heterosis of early maturing upland cotton.【Method】12 parent lines are divided into two groups initially,and correlation analysis of genetic distance based on the difference of phenotype and genotype and heterosis that is based on main characteristics in F1 was carried out.【Result】The average genetic distance based on 5 principal components of two groups parent lines was from 3.097 to 9.097 in range with an average of 5.535.Combined with SSR molecular markers result,the genetic distance was from 2.646 to 5.099 in range with an average of 4.18.In F1 of 36 combinations,the mid-parent heterosis of the growth periods,bolls per plant,boll weight,lint percentage,fuzz length,row cotton yield,and lint yield was 0.367,-1.256,14.176,6.691,1.000,11.206,and 15.235,respectively,the over-parent heterosis was-0.966,-1.464,6.457,0.110,-2.500,7.561,and 10.816,respectively.There was only an extremely significant positive correlation between the genetic distance based on the principal components and the mid-parent heterosis of F1 lint percentage.The genetic distance based on SSR molecular markers result had significant negative correlation with over-parent heterosis of lint percentage and fuzz length,mid-parent heterosis of the growth periods,respectively.【Conclusion】Early maturing upland cotton boll weight and yield characters had higher heterosis,and lint percentage had higher mid-parent heterosis.The genetic distance of two groups' parent lines is only significantly related with partial characters of F1,and has no simple linear relationship with yield.Genetic distances of partial characters increase with heterosis increasing but some properties decreased.