外源调控剂对香稻产量形成和茎鞘物质转运特性的影响

Effects of exogenous regulators on yield formation and transportation characteristics of stem and sheath matter in fragrant rice

【目的】探明外源调控剂对香稻产量形成、茎鞘物质转运特性及干物质积累的影响,以期筛选出对香稻增产优势明显的外源调控剂。【方法】以常规香稻品种美香占2号和象牙香占为试验材料,以喷施清水为对照(CK),设4个(T1、T2、T3和T4)调控剂配方处理,于破口期进行叶面喷施。抽穗期和成熟期分别取样测定干物质积累量,计算茎鞘转运特性;收获时测定产量及其构成因素。【结果】与CK相比,各调控剂处理均可提高可美香占2号的产量,增幅为5.36%~16.55%,但差异均不显著(P>0.05,下同);调控剂T1和T2处理可提高象牙香占的产量,其中T2处理较CK显著增产19.31%(P<0.05,下同)。抽穗期美香占2号的叶片干重在各调控剂处理下较CK显著增加12.86%~15.68%,象牙香占的茎鞘干重在T3处理下较CK显著提高11.35%。成熟期美香占2号的干物质积累量在各处理间均无显著差异,象牙香占的干物质积累量在各调控剂处理下整体较CK有不同程度的增加。各调控剂处理对两个香稻品种的收获指数及物质转运特性无显著影响。相关性分析结果表明,2个品种的产量与结实率、千粒重、抽穗后干物质积累量、抽穗期叶片干重和总干重及成熟期叶片干重呈显著正相关关系,与每穗总粒数、收获指数和抽穗期穗干重呈极显著正相关关系(P<0.01)。【结论】施用不同配方的外源调控剂可不同程度地调节香稻的每穗总粒数、结实率、千粒重及抽穗期和成熟期干物质积累量,从而不同程度地提高香稻产量。其中T1和T2处理分别对美香占2号和象牙香占具有产量优势,主要是在于可提高其每穗总粒数、抽穗期与成熟期干物质积累量。

【Objective】The effects of exogenous regulators on yield formation,transportation characteristics of stem and sheath matter,and dry matter accumulation of fragrant rice were explored in order to screen out the exogenous regulators with obvious advantages in increasing yield of fragrant rice.【Method】The conventional fragrantrice varieties Meixiangzhan 2 and Xiangyaxiangzhan were used as research materials.Foliar spraying was carried out at break stage with spraying clear water as the control(CK)and spraying four(T1,T2,T3 and T4)regulators as the treatments.At heading stage and mature stages,the rice seedlings were sampled respectively to determine the dry matter accumulation and to calculate transportation characteristics of stem and sheath.The yield and yield components were determined when the rice was harvested.【Result】Compared with CK,each regulator could increase the yield of Meixiangzhan 2 with the increment of 5.36%-16.55%,but the difference was not significant(P>0.05,the same below).Regulators T1 and T2 could both improve the yield of Xiangyaxiangzhan,and regulator T2 significantly increased 19.31%of the yield compared with CK(P<0.05,the same below).Leaf dry weight of Meixiangzhan 2 at heading stage was significantly increased by 12.86%-15.68%com-pared with CK under the treatment of each regulators,and stem and sheath dry weight of Xiangyaxiangzhan was significantly increased by 11.35%compared with CK under T3 treatment.At mature stage,dry matter accumulation of Meixiangzhan 2 was not significantly different between the treatments,while each regulators increased dry matter accumulation of Xiangyaxiangzhan to different levels.The regulators treatments had no significant influence on the harvest index and matter transportation characteristics of the two fragrant rice cultivars.Correlation analysis showed that the yields of the two cultivars were significantly positively correlated with seed setting rate,1000-grain weight,dry matter accumulation after heading,leaf dry weight and total dry weight at heading stage and leaf dry weight at mature stage,and the yields were extremely significantly positively correlatedwith grain number per panicle,harvest index and panicle dry weight at heading stage(P<0.01).【Conclusion】Applying different exogenous regulators can regulate grain number per panicle,seed setting rate,1000-grain weight and dry matter accumulation at heading stage and mature stage,thereby increase yield of frangant rice to different degrees.T1 and T2 treatments can improve the yields performance of Meixiangzhan 2 and Xiangyaxiangzhan respectively,which is mainly due to the increment of grain number per panicle,and dry matter accumulation at heading stage and mature stage.