杂交早稻垩白度的杂种优势和相关性研究

选用7个早籼稻恢复系和6个不育系,采用不完全双列杂交,配组42个杂交组合,对这些组合和亲本进行垩白度测定,进而分析了垩白度的中亲优势、超亲优势、亲本的一般配合力(GCA)、组合的特殊配合力(SCA)以及垩白度与其他性状间的相关性。结果表明,杂交早稻垩白度与亲本的GCA和组合的SCA具有密切的关系,通常GCA越低,SCA的方差越大,所配组合更易出现垩白度低的组合。垩白度低的不育系配组的组合,中亲优势多为正值;垩白度高的不育系配组的组合,中亲优势偏向负值。不育系对杂种垩白度影响较大,育种中应加强不育系的垩白度改良。

Study on the Heteorsis of Chalkiness and Correlation of Early India Hybrid Rice

The chalkiness ratio of 7 male-sterile lines,6 restorer lines and their 42 combinations were tested and the correlation between GCA,SCA and others and chalkiness ratio were investigated.The results showed that F1 chalkiness ratio had close correlation with GCA and the VAR of SCA.The lower GCA was,the larger VAR of GSA was,so that it was easier to choose the combination with lower chalkiness ratio.While the CMS chalkiness ratio was low,its mid-parent hybrid was positive,and while the CMS chalkiness ratio was larger,its heterosis of mid-parent hybrid was negative.The CMS had important effect on the F1 chalkiness ratio,so it should be importance to improve chalkiness ratio of CMS.