不同播期下优质稻桂华占、八桂香花后碳氮物质流转与籽粒生长相关性

The Relationship Between Post-anthesis Carbon and Nitrogen Remobilization and Grain Growth of High Quality Indica Rice Under Different Sowing Date

以桂华占、八桂香为材料,不同播期调控下,研究不同播期下优质稻花后植株碳氮流转与籽粒生长及品质的相关性。结果表明:(1)花后茎鞘、叶片干物质运转速度和运转率都与籽粒起始灌浆势呈正相关。籽粒活跃灌浆期、持续灌浆时间与花后茎鞘、叶片干物质运转速度和运转率呈极显著正相关。(2)播种期推迟不利于茎鞘碳同化物向穗部流转,茎鞘碳同化物转运对籽粒的产量和淀粉产量的贡献率表现为淀粉>可溶性糖>蔗糖,茎鞘碳同化物对籽粒产量及淀粉产量的贡献率远高于叶片。可溶性糖转运对籽粒产量和淀粉产量贡献率表现为SD1>SD2>SD3;蔗糖、淀粉对籽粒的产量贡献率表现为SD1>SD2>SD3。茎叶可溶性糖积累量的减少与籽粒直链淀粉含量和积累量增加是同步的,并且,茎叶可溶性糖积累量快速递减期(花后3～12 d)与直链淀粉含量和积累量快速递增期(花后6～12 d)同步。(3)播种期推迟减少茎鞘和叶片总氮的积累,籽粒氮收获指数降低,但是播种期的推迟却增加茎鞘和叶片器官蛋白氮积累,有利于籽粒蛋白质含量提高。

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 starch〉 sugar〉sucrose. The contribution rate of the remobilization of carbon assimilation of the soluble sugar to grain yield and starch yield was SDI〉SD2〉SD3. 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.