苜蓿叶象甲卵块在苜蓿植株上垂直分布的研究

Studies on the veritical distribution of egg masses of Alfalfa weevil(Gyllenhal) in the alfalfa branch

苜蓿叶象甲卵块分布在苜蓿植株层次之间，差异显著；在不同田块之间，差异不显著。分布区间随着生育期的变化而变化，在分枝期，主要集中在0～20cm，区间估计为[0．6524，0．7876]；在开花期，主要在0～60cm，区间估计为[0．8427，1．000]。苜蓿叶象甲每个卵块的卵粒平均数为8．4粒，卵块与卵粒数存在着显著的线性关系：y＝0．0069＋8．6594xr＝0．8422**

Egg masses of different stratification of alfalfa branch is significantly different. The difference of different field is not apparent. With developing of postemergence. the vertical distribution of egg masses significantly changes. In the period of branch. it is significantly divided into three stratifications, egg masses is distributed mainly over the range between 0 and 20cm. With estimation of the confidence interval of the number of egg masses between them are 65.24% and 78.76% (95% confidential degree). In the period of blooming, it is divided only into two, egg mascs is distrituted mainly over the range between 0 and 60cm.With an estimation of the confidence between them arc 84.27% and 100% (95% confidential degree). The average egg number of each egg masses is 8.4. There is a apparent linear relationship between egg masses and egg number. The equation is.y=0.0069+ 8.6594 x r=0.8482**