杂交粳稻不同穗位垩白性状的差异与遗传率分析

Separated Properties in Chalky Traits of Grains Located at Different Positions within a Panicle for Japonica Hybrid Rice

以辽宁省近年审定的2个杂交粳稻组合9946与1052及其对应亲本为材料,对稻米垩白品质性状在穗上不同部位和不同枝梗上的分布特点和遗传差异进行研究。结果表明:垩白米率、垩白面积和垩白度表现了下部穗位最大,中部和上部穗位次之,二级枝梗大于一级枝梗。差异大的组合(9946)遗传率大,一级枝梗的遗传率大于二级枝梗的遗传率。垩白性状受遗传、栽培条件以及穗位与遗传互作的影响。因此,选择垩白性状差异小,而其他性状优良的亲本进行组配,结合合理的株型育种,有可能育出低垩白的优质组合。

Two japonica hybrid rice cuhivars （9946 and 1052）, released in recent year in Liaoning Province, and their parents were used to investigate their chalky traits, their difference in spatial distribution and genetic derivation of chalky appearance among grains located different positions within a panicle. The results showed that grains on the basal rachis in a panicle generally exhibited the greatest chalkiness grain rate, chalkiness area and chalkiness degree, followed by those at the middle part, the grains on a secondary branch were greater than those on a primary branch. If the difference between both parents enlarged, the relevant heritability would be increased. On the other hand, Chalky traits were influenced by heredity and cultivated condition. Therefore, the hybrid with low chalkiness degree could be developed by the combination of good varieties with small distinction in chalkiness degree with excellent cultivated technique.