Abstract:

The objective of this research was to establish the quality breeding theory of hybrid early rice in Yangtze River area through exploring the breeding means of the quality improvement of hybrid early rice. The hybrid early rice combinations between 6 sterile lines(A) and 5 restorer lines(R) of early indica rice grown in large area of Yangtze River basin were weed with NCⅡ genetic design, and 12 quality traits of them were measured and analyzed in this research. The result showed that the values of most grain quality traits were between their parents, chalky and milled rice rate were main limiting factors of the hybrid early rice quality in Yangtze River area. The statistical analysis revealed that there were a highly significant genetic difference among combinations and a highly significant influence of the quality-gene additive and non-additive effects on the hybrid early rice quality. The narrow-sense heritability of quality traits was ranged as follows: Length/Width > Length > Chalkiness >Width > Head Rice >Gelatinization temperature >Amylase Content >Chalky Grain >Chalky Area > Brown Rice > Gel Consistency >Milled Rice. Simple analysis of correlation showed that there existed significantly positive correlation between brown rice and milled rice; head rice and gelatinization point; grain length and grain length/grain width; grain width and chalky grain, chalky area, amylose content; chalky grain and milled rice width, chalky area, amylose content, chalky area and grain width, chalky grain, chalkiness, amylose content. There existed remarkably negative correlation between head rice and chalky grain; grain length/grain width, chalky grain, chalky area, chalkiness, gelatinization temperature, amylose content. The internal relationship, genetics and their improvement in 12 quality traits of hybrid early rice were discussed also.

Key words: Early hybrid rice, Quality characters, Combining ability, Heritability, Correlation