Comparisons of RVA Profile Characteristics of Grains at Different Grain Positions of Panicle between Two Panicle Types of Japonica Rice

Under the field conditions,three Japonica cultivars with erect panicle and three Japonica cultivars with curved panicle were applied to compare the difference of RVA profile characteristics in the grains between different grain positions in two different panicle type.Results indicated the range of difference and variation coefficient(CV)of RVA profile characteristics in the grains between different grain positions varied with cultivars,which had no correlation with panicle type.The variation in starch viscosity characteristics of different grains within a panicle was closely related to the flowering order of rice grains on the rachis branches.Starch viscosity characteristics for the grain of the spikelets that flowered earlier were superior to those for the grain of the spikelets that flowered late.RVA profile parameters for the grain 1,6 and 5 on the primary branch showed the highest,the grain 2 the lowest.The order of RVA profile parameters on a secondary branch within a panicle was the grain 1the grain 3the grain 2.From space,starch viscosity characteristics are gradually deteriorate from top to bottom in the entire spikelets.