杂交粳稻主要农艺性状的配合力及遗传力分析

目的]分析杂交粳稻主要农艺性状的配合力及遗传力,探讨三系亲本的配合力、遗传力等规律及参数。方法]以5个千粒重介于23.5～27.4 g的BT型不育系和40个千粒重介于18.7～31.2 g的三系粳稻恢复系,采用p×q不完全双列杂交(NCⅡ)设计,配制200个杂交F1为试验材料,对9个主要农艺性状的配合力进行分析。结果]母本一般配合力方差除单株有效穗、每穗实粒数和单株谷重3个性状外,其他6个性状均达极显著水平;父本一般配合力方差和组合特殊配合力方差均达极显著水平。在组合的单株谷重性状中以非加性效应为主,而其余8个性状均以加性效应占主导地位。组合的所有性状受恢复系的影响比受不育系的影响大。各农艺性状狭义遗传力的大小顺序依次为千粒重>株高>播始历期>结实率>穗长>每穗总粒数>每穗实粒数>单株谷重>单株有效穗数。结论]该研究可为进一步选择和利用这些不育系、恢复系及其配组F1杂种优势提供理论依据。

Analysis of Combining Ability and Heritability of Major Agronomic Characters of Japonica Hybrid Rice

Objective] The aim was to analyze the combining ability and heritability of major agronomic characters of Japonica hybrid rice,and discuss the law and parameters of the combining ability and heritability of the parents of the three-line.Method] 5 BT-type cytoplasmic male sterility(CMS) lines and 40 three-line japonica restorer lines with major difference in 1 000-grain weight were chosen to analyze the combining ability of 9 agronomic characters by way of p×q incomplete diallele cross(NCⅡ) design.Result] Both general combining ability(GCA) and specific combining ability(SCA) of all the characters were significant at 1% level except for the number of panicles per plant,filled spikelets per panicle,grain weight per plant in which the GCA of female was not significant.The additive variation was principal in days from sowing to heading,plant height,panicle length,panicles per plant,spikelets per panicle,filled spikelets per panicle,seed setting rate,1 000-grain weight while the nonadditive variation was greater in grain weight per plant.All characters were influenced more greatly by restorer lines than by male sterile lines.The h2N was ordered from high to low as 1000-grain weight,plant height,days from sowing to heading,filled spikelets per panicle,seed setting rate,panicle length,spikelets per panicle,filled spikelets per panicle,grain weight per plant,panicles per plant.Conclusion] The study provides a theoretical basis for selecting and utilizing the heterosis of these CMS lines,restorer lines and their F1.