喜树幽斑螟自然种群生命表的研究

1996～ 2 0 0 1年在福建省南平、沙县对喜树幽斑螟自然种群进行系统调查 ,组建和分析了 5个世代的自然种群平均生命表 ,结果表明 :喜树幽斑螟各世代自然种群存活曲线均属 Price A型 ,第 1～ 5代平均种群趋势指数 I值分别为 6.40、 4.66、 4.5 3、 4.88、 3.1 8. 5个世代中 ,影响喜树幽斑螟种群生命过程的关键因子均为成虫死亡和生殖力下降 .第 1～ 3代中 ,自然消亡的控制作用均大于寄生和捕食 .第 4代中 ,寄生的控制作用更大 ,第 5代则捕食的控制作用大 .年周期中 ,天敌对种群系统的控制作用随着时间的延续逐渐加强 .成虫期是各个世代的关键虫态 ,除成虫期外 ,第 1代的关键虫态为 3～ 4龄幼虫 ,第 2～ 4代的关键虫态为 1～ 2龄幼虫 ,第 5代的关键虫态为蛹期

Study on the Natural Population Life Table of Pyla sp.

The 5 generation of average natural population life tables of Pyla sp were studied in Nanping and Shaxian County,Fujian Province by means of systematic investigation in 1996~2001 The results indicated that the type of 5 generation's survival curves of the population all belonged to Price's type A;the 5 generation's trend indexes of the average population were 6 40,4 66,4 53,4 88 and 3 18 respectively;in 5 generation,the key facts effecting population's change were all the death of adults and the declination of adult's reproduction;in 1st~3rd generation,the control efficiencies of natural disappear were all bigger than parasite and predator;in 4th and 5th the biggest control efficiency were parasite and predator respectively;in year cycle,the natural enemy's control efficiency to population were enhanced with the development of time in 5 generation;besides the adult phase which were the key phases of all the population,the phase of 1~2 age larva in 2nd~4th generation, the 3~4 age larva in 1st generation and the pupa in 5th generation were all the key phase