蓖麻Lm型雌性系及其杂交组合的杂种优势分析

Heterosis Analysis of Castor Lm-type Female Lines and Their Hybrid Combinations

为了解Lm型雌性系蓖麻的配合力遗传基础,以5个蓖麻Lm型雌性系为母本,3个蓖麻两性系为父本,根据NC-Ⅱ不完全双列杂交组配15个杂交组合,对蓖麻杂交组合的配合力、遗传力以及杂种优势进行分析。结果表明:雌性系A1和两性系B2的GCA和杂交组合SCA在蓖麻大部分农艺性状中均表现优秀,可在提高蓖麻产量的亲本选育中作为优异亲本进行杂交组合的构建。对亲本杂种优势研究发现,两性系B2参与组配的杂交组合在多个农艺性状上表现为强杂种优势,而Lm型雌性系则表现为在单个性状上具有较强的杂种优势。从遗传力分析结果来看,蓖麻的主茎蒴果数、一级分枝蒴果数、主茎穗长、主茎节数、一级分枝百粒质量和产量受加性效应和非加性效应共同影响,且受环境影响较小,适宜在早代进行选择。

In order to understand the genetic basis of combining ability of Lm-type female line castor,this study analyzed the combining ability,heritability and heterosis of castor hybrid combinations with five castor Lm-type female lines as the maternal parents and three castor bisexual lines as the male parents.A total of 15 hybrid combinations were formed according to NC-Ⅱincomplete diallel cross group.The results showed that the General Combining Ability(GCA)and Specific Combining Ability(SCA)of female line A1 and bisexual line B2 showed excellent performance in most agronomic traits of castor.These lines could be used as excellent parents in constructing the hybrid combinations for parental breeding to increase the yield of castor.The study of parental heterosis found that the hybrid combination of bisexual line B2 exhibited strong heterosis in multiple agronomic traits,while the female line of Lm showed strong heterosis in single traits.Based on the results of heritability analysis,traits such as the number of capsules on the main stem,capsules on the primary branch,spike length of the main stem,the number of nodes on the main stem,hundred-grain mass in primary branch,and yield of castor were affected by both additive and non-additive effects,and these traits were less affected by the environment,making them suitable for selection in the early generation.