Development Of Near Isogenic Lines Of Starch Synthesis Related Genes And The Investigation Of The Effect Of The Genes On Cooking Quality In Rice (Oryza Sativa L.)

In order to investigate of the effect of the genes responsible for starch synthesis on cooking quality in rice, near isogenic lines (NILs) were developed, which used an indica variety with poor quality, Guichao 2, as the recurrent parent and a japonica waxy variety with good quality, Suyunuo, as the donor parent. Then, by using the gene-tagged molecular markers, several candidate individuals containing starch synthesis-related genes were selected for analysis of starch physicochemical (properties apparent amylose content, consistency and the Rapid Visco Analyser profile). The main results were shown as followings:1. There was no significant difference on most agriculture properties between the NILs and the recurrent parent, which indicated that the backgrounds of the near isogenic lines were nearly the same to the recurrent parent. But as to most NILs, the fertility was lower and the length of the rice was longer than the recurrent parent.2. The allelic differences of all amylopectin synthesis-related genes detected between two rice cultivars almost had no significant effect on the apparent amylose content (ACC). There was a significant effect on ACC in BC3F2 population due to the allelic difference of Sssâ…¢-1 and Sbe4 between two rice cultivars, and the same result of Sbe1 in BC5F2 population.3. The allelic differences of all amylopectin synthesis-related genes detected between two rice cultivars had no significant effect on gel consistency (GC). It was special that GC of NIL- Sss1 was softer than that of Guichao 2 in the three populations, although the difference was not significant. Hereby we can infer that there was locus controlling GC near Sss1 gene or in Sss1 gene locus.4. The allelic differences of all genes detected except for Sbe4 between two rice cultivars had significant or highly significant effect on the Rapid Visco Analyser (RVA) profile,and the effects varied with genes. The results from the three populations were complicated, but the results of BC4F3 and BC5F2 population seemed to be consistent. Therefore, steadier and more accordant results will be obtained from higher population of the NILs.5. The allelic difference of Wx had significant effect on ACC, GC and RVA profile which suggested that Wx gene played an important role in rice quality formation.6. The effect of Sss1 on starch physicochemical properties was different under the background of Wx and wx gene respectively, which demonstrated that the allelic difference of Wx gene significant influenced the function of Sss1.