The Relationship Between Post-anthesis Carbon and Nitrogen Remobilization and Grain Growth of High Quality Indica Rice Under Different Sowing Date
Field experiments were conducted in a randomized complete block design with Baguixiang and Guihuazhan as materials under three sowing date to investigate the relationship between post-anthesis carbon and nitrogen remobilization and grain growth of high quality indica rice after flowering in 2009.Results indicated that grain growth was closely correlated with carbon and nitrogen remobilization under three different sowing date conditions.(1)Initial grain filling potential was significant positive correlated with dry matter remobilization rate and efficiency of culm and sheath;maximum grain filling rate,active filling period and active grain filling duration were significant positive correlated with leaf dry matter remobilization rate and efficiency after flowering and significant negative correlated with clum and sheath.(2)Delayed sowing date was not beneficial to the carbon assimilation in stem and sheath remobilization to the panicle.The contribution rate of the remobilization of carbon assimilation of culm and sheath to grain yield and starch yield which was far more than leaf blade was starchsugarsucrose.The contribution rate of the remobilization of carbon assimilation of the soluble sugar to grain yield and starch yield was SD1SD2SD3.The soluble sugars accumulation of stem and leaf reduced along with the increase in grain amylose content and accumulation increased.The rapid decline period(after flowering 3～12 d)of soluble sugar accumulation in leaves was synchronized with the rapid increase amylose content and accumulation period(after flowering 6～12 d).(3)The sowing date postpones reduced the accumulation of total nitrogen of culm and sheath and leaf,grain nitrogen harvest index decreased,but the delay in sowing date protein nitrogen accumulation was increased culm and sheath and leaf.