基因型×环境互作效应对水稻茎秆抗倒性杂种优势的影响

Effect of genotype×environment interaction on heterosis for lodging resistance of the culm in rice

用包括基因型×环境互作效应的加性—显性—加性×加性上位性遗传模型和统计方法 ,对水稻茎秆抗倒性杂种优势进行了研究 .结果表明 ,评价水稻茎秆抗倒性的 5个性状 (秆长、茎粗、茎基抗折力、秆型指数和抗倒指数 )的杂种优势既由基因型控制也受环境 (年份 )互作效应影响 .茎粗对环境的敏感性较弱 ,表现较低的正向群体平均优势和负向群体超亲优势 .基因型×环境互作效应影响了秆型指数和抗倒指数杂种优势表达的程度和方向 .秆长、茎基抗折力在不同环境中均表现正向基因型×环境互作效应 。

Genetic studies were conducted on heterosis for lodging resistance of the culm in rice (Oryza sativa L.), by using genetic models including genetic effects and genotype×environment(GE) interaction for additive dominant additive×additive epistasis. The results indicated that heterosis for lodging resistance of the culm in five traits, such as culm length (CL), culm thickness (CT),breaking strength of the based culm with leaf sheaths (BSBCLS),culm type index (CTI) and resistant index to lodging (RIL) were affected by genotype and environmental factors (i.e year). Slight positive heterosis over mid parents based on population mean (H MP ) and negative heterobeltiosis based on population means (H BP ) were observed in CT, because of its insensitivity to environment, The expression extents and directions of heterosis were influenced by GE interaction in CTI and RIL. However, the same direction positive GE interaction effects were also observed in CL and BSBCLS on different environments. It implied that the heterosis could be enhanced by improving environmental conditions.