Study of genes action in the control of traits effective in the quality of cooking rice

Considering the growing demand for top quality rice varieties, it is essential to reform rice to improve its nutritional values without significant decrease in its yield. This study dealt with how genes action controlled the traits effective in the quality of cooking rice. For this purpose a cross combination of four rice varieties viz., Nada, IR36, IR65, SHZ2. These varieties have different levels of those traits effective in the quality of cooking. The results showed that the general heritability of such traits as amylase content, gel consistency, and gelatinization temperature were, respectively, % 98, %97, and %95. Based on the variance of the studied parental along the regression line (wr to vr) it was inferred that the parent IR65which in relation to the central point was in the farthest point had the highest variance and, consequently, higher dominant alleles. The parental of Nada and IR65 had the lowest variances and, consequently, had higher dominant alleles. The mean squares of general and specific combining ability for amylase content at the probability level of 1% was significant showing the importance of the additive and non-additive effects of genes on genetic control of this trait. Therefore, the selection-based reforming methods for improving this trait have a high efficiency and the efficiency of selection for this trait in the segregating generation will, also, be high.