褐飞虱为害水稻不同生育期对产量的影响

ON THE YIELD LOSSES OF RICE DAMAGED BY BROWN PLANTHOPPER IN DIFFERENT STAGES

应用二次旋转回归设计和通径分析方法研究了不同生育期受褐飞虱为害,水稻产量损失和产量构成因素的变动规律。结果表明,在同等虫量下,受害生育期越早,损失越重。抽穗期和乳熟期的连续为害对实粒数的影响较大;灌浆期受害对千粒重的影响较大。3个生育期间的互作效应明显,表明褐飞虱连续为害,产量损失有加重的趋势。总受害量大于3个生育期受害量的简单线性累加,前期受害可降低后期的水稻生活力和光合强度。

Rotational quadratic regression design and path analysis method were used to explore the yield losses of rice damaged by brown planthopper(BPH,.Nilarpavata lugens Stal) and the dynamics of constitutional factors of rice yield in different stages. The results showed that .under the same population density of BPH ,the earlier the damage , the more severe the yield losses caused. The successive damage during heading to milk stages mainly reduced the seed setting rate ,and that in filling stage mainly reduce the thousand kernal weight. The significant interactions among the three stages,i.e. the total yield losses was significantly higher than the linear accumulation of the losses caused separately in three stages,indicated that the yield losses was increased by the successive damage of BPH,and the injury in earlier stage decreased the vitality and photosynthesis intensity in later stage.