杂交水稻孕穗期的耐涝农艺指标评价

[目的]筛选耐涝水稻品种。[方法]选择WY56、香125S/D68等18个三系和两系杂交水稻组合,于孕穗期没顶淹涝72h,淹水后对杂交组合的茎蘖数、成穗率、纹枯病指数、高位芽率、包茎率、幼穗死亡率、结实率、千粒重和单蔸产量共9个农艺性状的相对受害率进行调查分析。[结果]纹枯病指数、高位芽率、包茎率、幼穗死亡率4个性状在受淹后呈上升趋势;其他则与产量的变化相一致呈下降趋势。与产量相对受害率相关最密切的依次是结实率、高位芽率和千粒重,其相关系数分别为0.468、0.465和-0.456,达显著水平;较密切的为纹枯病指数和茎蘖数,其相对受害率与产量的相关系数为-0.343和0.334。[结论]结实率、高位芽率、千粒重、纹枯病指数和茎蘖数5农艺性状可作为评价一个水稻组合或品种孕穗期耐涝能力的主要农艺指标。

Evaluation of Agronomic Index of Hybrid Rice for Submergence-tolerance at Booting Stage

[Objective]The study was aimed at screening for submergence-tolerance rice varieties.[Method]18 hybrid rice combination including Weiyou56 etc.were submerged for 72 h at booting stage.Relative damage percentage for 9 agronomic characters relating to tiller number,panicle rate,sheath blight index,high bud rate,packet neck rate,mortality of young panicle,seed setting rate,thousand-grain weights and single-plant yield were investigated and analyzed.[Result]The RDP of leaf sheath blight index,high bud rate,packet neck rate and mortality of young panicle increased,others were consistent with the changes in yield production decline.Seed setting rate,high bud rate and thousand-grain weights correlated with the RDP of yield,the correlation coefficient was 0.468,0.465 and-0.456 respectively,and reached significant levels;The correlation coefficient of leaf sheath blight disease index and tiller number to yield were-0.343 and 0.334 respectively.[Conclusion]Seed setting rate,high bud rate,thousand-grain weights,leaf sheath blight disease index and tiller number could be used as index of submergence-tolerance ability at rice at booting stage.