亚种间杂交稻籽粒充实率表现及其配合力

GRAIN FILLING AND COMBINING ABILITIES OF JAPONICAL/INDICA HYBRIDS

以５个典型的粳型广亲和材料和５个典型籼稻品种为亲本，按ｐ×ｑ模式配组出２５个亚种间杂交组合，分析亚种间杂交稻籽粒充实率和受精率，结果表明：（１）亚种间杂交稻不同基因型籽粒充实率和受精率间不存在显著相关，是２个独立表现的性状。（２）籽粒充实不良的表现具有全穗性，但籽粒充实率在不同粒位间存在一定的差异，上位＞中位＞下位。（３）供试各父母本的籽粒充实率的一般配合力效应具有显著差异，各供试组合的特殊配合力效应亦达显著水平。在亚种间杂交稻的籽粒充实率的遗传中，加性效应和非加性效应相互独立，共同决定其性状表现。试验证明通过遗传改良提高亚种间杂交稻的籽粒充实率是完全可能的，选配得当可得到籽粒充实率和受精率俱高的优良亚杂组合。

An experiment was carried out to study the grain-filling and fertilitles of 25 hybrlds between 5 typical wide compatibility Jing(O. Japonica )varieties and 5 typical Xian(O. Indica )rices. The results are as follows : The fertility and grain,filling are not significantly correlated.they are two independent traits. The position effects of grain-filling exist,ie,the grains of upper panicles are better than those in middle,which are furiher better than those of lower parts. However,the low grain- filling is generally on whole pan-icles for some combinations,There are apparent differences in general combining ability of parents. The spe-cial combining abillties are also significant in some combinatlons. The genetic expression of the trait is controlled by both additive and non-additive effects. It is feasible to improve the grain-filling of varietal hybrids by selecting suitable parents and some special combinations.