Effects of Water Supply on Rice Quality During Grain Filling Stage in Cold Region

By selecting two cultivars of Kenjiandao 5(K5) and Kendao 12(K12) as materials and measuring soil water potential(SWP) by soil moisture tensiometer,the effects of water supply on rice quality in grain filling stage were studied using potted planting method within a rainproof chamber.The primary results indicated that in the intermittent irrigation treatment with the SWP of-8~-10 kPa in grain filling stage,the head rice rate for K5 was increased and its chalkiness rate and chalkiness degree was decreased,while the head rice rate for K12 was decreased and its chalkiness rate and chalkiness degree were increased.The amylose content,fat content and protein content of grains at each grain position of two varieties were enhanced and the rice taste values for the two varieties were reduced.In the unremitting irrigation treatment with the SWPs of-18~-20 kPa and-28~-30 kPa before the filling stage,the head rice rate for K5 was increased;the head rice rate for K12 was increased and its chalkiness rate and chalkiness degree were decreased;the length/width and protein content at each grain position of the two varieties were increased;and the rice taste values for the two varieties were reduced.