杂交水稻稻米外观品质性状的遗传相关分析

GENETIC ANALYSIS ON EXTERIOR QUALITY TRAITS IN HYBRID RICE

用６个不育系和恢复系按不完全双列杂交组配的材料，研究了稻米外观品质性状的遗传效应及相关关系。结果表明，稻米外观品质性状均以加性基因效应为主，不育系的作用大于恢复系。千粒重、粒长和长宽比具有较高的广义和狭义遗传力。垩白率和垩白面积的遗传力较小。长宽比与粒长、垩白率与垩白面积和粒宽均呈极显著正相关。长宽比与粒宽、垩白率与社长呈极显著负相关。通径分析结果与简单相关的趋势一致。千粒重对长宽比主要通过粒长间接影响，直接作用较小。本文还分析讨论了优质高产组合的育种途径。

crosses were made with a few CMS lines and restorer lines according to method ofincomplete cross in order to study the inheritance of exterior quality traits in hybrid rice.The results indicated that all of the 6 exterior quality traits were mainly govermed by theadditive gene effects and determined by the female parents.1000-grain weight ,kernallenghth/width all had very higy and ;chalky area and chalky rice percentage had lowheritabilities ,their were 38.4l%and 35.31% respectively. Correlations betweenlength/width and chalky area ,chalky rice percentage and kernal length ,chalky ricepercentage and kernal width were significantly positive,but length/width and kernalwidth,chalky rice percentage and kernal length were significantly negative. The results ofpath analysis showed that direct path coefficients from kernal length,kernal width and1000-grain weight to length/width were 0.7044,-0. 425l and 0.0123 respectively,thedirect path coefficients from chalky area,kernal width,1000-grain weight and kernal lengthto chalky rice percentage were 0.5136,0.4348,0.3607 and -0.1762 respectively. It issuggested that,in order to get desirable exterior quality through breeding,it is necessary toreduce the chalky rice percentage and to increase the kernal length and shorten the kernalwidth.