Genetic Research For Low Amylose Content Of Rice

The experiment was based on breed practice. The different amylose content rice were selected in experiment. Three cross combinations (combination1- low AC×high AC, combination2- low AC×middle AC, combination3- middle AC×low AC) were configured, and Eleven quality traits and eight agronomic traits were studied. In order to realize the heredity disciplinarian of low amylose content, offer theory for low amylose breeding and amylose improving in Heilongjiang. The result showed:Degree of variation of quality traits in low amylose's cross F2, F3 generation showed that: the degree of variation of chalkiness ratio was biggest in physical quality. The degree of variation of amylose content was biggest in steamed wheaten quality, so it was possible to select single plant of low amylose and low chalkiness ratio. In milled quality only the degree of variation of brown rice ratio of combination 1's F2 generation was biggest, combination 1's F3 generation and combination 2, combination 3's F2, F3 generation the degree of variation of head rice ratio were biggest.Correlation of amylose content and 10 quality traits in F2, F3 generation showed that: in F2, F3 generation the represent of combination 1 was very good, the possibility was offered in low amylose, good physical quality and good milled quality. These showed great difference of amylose content were used which was likely to select single plant of high quality and low amylose. In F2 generation, combination 3 offered the possibility low amylose and good physical quality. In combination 2 if single plant of low amylase was selected, its'physical quality, milled quality and nurture quality would be descend, which was not fit for breed aims. In F3 generation, single plant of low amylose was selected, its'physical quality would be improved and milled quality would be descend in combination 2 and combination 3, which showed it wasn't possible to select to single plant of high quality and low amylase.The principle component analysis showed that head rice ratio, amylose content, chalkiness ratio, gelatination consistency and protein content were most quality traits in low amylase content (5-15%) , and head rice ratio, amylose content and chalkiness ratio were most quality traits in low amylase content (5-15%).Correlation of amylose content and 8 agronomic traits showed that: if single plant of low amylase was selected, its'agronomic traits would be affected in negative. Tassel time of low amylose content in 3 combinations was early in their tassel time, and it was important time to select it.The standard of good and low amylose rice: plant height 80-90cm; panicle numbers 15-18; panicle length 18-21cm; yields of per plant 30-35g; empty ratio <5%.