籼粳稻杂交后代穗部性状变异及其相互关系研究

为了探讨籼粳稻杂交后代穗部性状表现规律,为综合亚种优点充分利用亚种间优势提供理论依据,分析了典型籼粳稻杂交后代穗部性状的变异及其相互关系,并依穗型指数分类比较穗部性状差异。试验结果表明:穗部性状在F1代多表现超亲优势,F6代呈现连续变异,出现很多超亲值和中间性状。穗粒重由3个主成分决定,粒数因子、穗型因子和粒重因子分别贡献了45.49%,17.6%和12.22%,穗长有使粒数增多、粒重增加的趋势。RIL群体内绝大多数株系穗型属于中、下部优势型,结实率等穗部性状在不同穗型的分布既有交叉又有重合。因此籼粳稻杂交可以创造大量变异,其后代具有较强的杂种优势,可以实现穗部性状的重新组合,群体内多数株系穗型属于下部优势型,依据穗型很难判别穗部性状的优劣。

Variations and Relationships of Panicle Characteristics in the Filial Generation of Cross between Indica and Japonica

The principle of the variations and relationships of panicle characteristics in the filial generation of cross between indica and japonica were studied.The research was to set up a scientific basis for combination of ideal characters and utilization of vigor through cross between indica and japonica.The differences were studied based on the panicle type index.The results indicated that most panicle characteristics showed heterobeltiosis in F1 generations,and a continuous variation in F6 generations.The filial generation showed heterobeltiosis and mid parent heterosis.The panicle characteristics were recombined in the filial generation.The grain weight per panicle depended on three principal factors,which were the number of grains,the panicle type and the grains weight,whose contributions were 45.49%,17.6% and 12.22%,respectively.The long panicle could make the number of grains and the grain weight increase.Most panicle characteristics in the population belonged to the superior-on-the-middle-part and superior-on-the-lower-part type.Large variations could be created through cross between indica and japonica.The vigor was significant in the filial generation of cross between indica and japonica.It is difficult to determine which panicle type is optimum.