Abstract:

The aim was to enhance the selection effenciency of major quality traits for rice varieties (lines) and to provide theoretical basis for rice breeding. The relationships between amylose content, protein content, RVA profile, palatability value and physic-chemical quality properties of cooked rice of twenty-two new bred rice lines were studied. The results showed that, the determination of the thirteen quality indicators in the tested lines both had a very significant difference. A significant difference had been showed among the eight quality indicators in the tested lines. The coefficient of variation of amylose content was minimum, while coefficient of variation of protein content was maximum. Coefficient of variation of the peak viscosity, breakdown and setback between the lines were larger than those of other RVA profile characteristics. The palatability value was negatively correlated to the amylose content and the setback with a significant coefficient of -0.630** and -0.736** respectively, and positively correlated to the peak viscosity and the setback with a significant coefficient of 0.695** and 0.618**. Contribution rate of the two main ingredients being selected could reach 82.39% by the principal component analysis. Accumulating contribution ratio of first principal component factors to the rice quality reached to 44.21%. Factor loadings of the breakdown and amylose content, and final viscosity were larger in the first principal. Appropriate decreasing the first and fourth principal component factor and increasing the second and third principal component factor would be favourable for improving the qualities of rice lines.