超大穗型水稻R1126及其组合穗颈输导组织与籽粒灌浆结实的关系

Relationship Between the Conducting Tissue in the First Internode and the Grain-filling of Super Large Panicle Rice Restore Line R1126 and Its Derived Combinations

以汕优63为对照,对超大穗型水稻父本R1126及所配4个组合产量、籽粒灌浆充实特性和穗颈输导组织特征进行分析。结果表明,R1126所配的杂交组合产量比汕优63高7.43%～24.23%,每穗总粒数和实粒数的增加是其增产的主要途径。R1126所配杂交组合穗颈粗度、茎壁面积、茎壁面积与节间横切面积之比、维管束数目、维管束总面积、韧皮部总面积、韧皮部总面积与维管束总面积之比和输导组织活性均高于汕优63,其颖花数/维管束面积、颖花数/韧皮部面积、总库容/维管束面积、总库容/韧皮部面积、实粒重/维管束面积、实粒重/韧皮部面积均低于汕优63,有机质向穗部的转运也较通畅,强、弱势粒籽粒灌浆起始生长势（R0）大、最大灌浆速率（GRmax）和平均灌浆速率（GRmean）高,达到最大灌浆速率的时间（Tmax）早,活跃灌浆期（D）和有效灌浆期（T99）短,籽粒灌浆迅速,动态合理,强、弱势粒（SG、IG）生长终值量（A）差值小,籽粒充实良好。相关分析表明,颖花数/韧皮部面积、总库容/韧皮部面积、实粒重/韧皮部面积与强、弱势粒的GRmax和GRmean负相关,与谷粒充实率负相关,与D、T99和Tmax正相关;输导组织活性与强、弱势粒GRmax和GRmean显著或极显著正相关,与谷粒充实率正相关,与D、T99和Tmax正相关。穗颈输导组织与籽粒灌浆结实关系密切,改善穗颈输导组织特性有利于籽粒灌浆结实。

The grain yield,the characteristics of conducting tissue in the first internode and their relations with the grain-filling were analyzed by using four hybrid rice combinations derived from R1126as materials and Shanyou 63as a control.The results showed that the grain yield of the four hybrid rice combinations was 7.43%to 24.23% higher than that of Shanyou 63.Increased total grain number and filled grain number per panicle attributed to yield increase.Compared with Shangyou 63,hybrid rice combinations derived from R1126had advantages in the neck diameter,area of stem wall,ration of stem wall to cross,No.of vascular bundles（VB）,total area of VB,total area of phloem,the ratio of VB area to phloem area as well as conducting tissue activity,while had lower ratio of spikelet number to area of VB,ratio of spikelet number to area of phloem,ratio of total sink to area of VB,ratio of total sink to area of phloem,ratio of full grain weight to area of VB,ratio of full grain weight to area of phloem,and the organic material transfer to panicle was fluency.The derived hybrid rice combinations were characterized by greater initial grain-filling potential（R0）,maximum grain-filling rate（GRmax）and mean grain-filling rate（GRmean）,earlier maximum grain-filling rate（Tmax）,shorter active grain-filling period（D）and effective grain-filling time（T99）,faster grain filling and reasonable filling dynamics,smaller d-value of final weight of a kernel（A）between superior and inferior grains,which contributed to good grain-filling.The correlation analysis showed that the ration of spikelet number,grain weight,total sink capacity to area of phloem were negatively correlated with GRmaxand GRmeanof SG and IG,and grain-filling rate.And D,T99,Tmaxwere positively correlated with them as well as conducting tissue activity.Conducting tissue in the first internode had closed relationship with grain-filling,improving its characteristics could be beneficial to grain filling.