Abstract:

【Objective】 This study was performed to investigate the reason of the difference in the two rice varieties with similar apparent amylose content (AAC) by analyzing the dynamic formation of rice quality. 【Method】 Two rice cultivars Wuyujing3 and 30you917 with similar apparent amylose content were used as materials. The dynamic changes of gel consistency and RVA profile of the developing grains during the quality formation were studied. 【Result】 The differences were obviously found in the dynamic changes of amylose content, gel consistency and RVA profile of the developing grains. The difference in dynamic change of amylose content in two varieties from 5d to 15d after anthesis was significant, while the contents of amylose were nearly equal at late grain-filling stage. Gel consistency and RVA profile between the two varieties varied in the grain-filling period. The gel consistence of Wuyujing3 was softer than that of 30you917 at 5-10 d after anthesis, while harder than that of 30you917 at 20-40 d after anthesis. During the determination of RVA profile, Wuyujing3 represented higher stickiness such as big breakdown, small positive setback and low pasting temperature compared to 30you917. 【Conclusion】 These results suggested that the differences in the dynamic formation of the main quality indices during grain filling were the representation of the diversities of rices with similar apparent amylose content. It was Wuyujing3 that provided with higher peak viscosity, breakdown and lower positive setback during the formation of rice kernel and had high cooking and eating qualities.