柑桔潜叶蛾自然种群动态及防治策略的研究

从1980年至1985年,在广州市郊的柑桔园研究了柑桔潜叶蛾Phyllocnistis citrella(Staint.)]自然种群生命表.用Manly的关键因子分析法对五个同次世代的生命表材料进行分析,结果表明,影响关键世代种群变动的关键因子是一龄幼虫自然死亡和二龄幼虫捕食.各发育阶段的天敌因子对关键世代种群变动的影响力达64.6%.据此制定了保护天敌的防治策略,经实践证明,采用此措施可推迟下一代峰期的出现时间,有利于柑桔秋梢在最合适的时间抽放.

STUDIES ON POPULATION DYNAMICS AND CONTROL STRATEGY OF THE CITRUS LEAF MINER

The life tables of natural populations of the citru leaf miner, Phyllocnistis citrella Stn., were studied in Guangzhou suburbs from ,1980 to 1985 The analytic: method proposed by Manly.(1977) was chosen for detecting the. key factor causing population; change for each of the five generations investigated in each year. The result shows that important sources of variation in population of the key generation (late summer generation) are the weather and disease in the period of the first larval instar, the predators and parasites in the period of the third larval instar and predators in the period of the second larval instar, where these account for 27.0%, 32.0% and 12.3% respectively of var (I). The proportion of the affecting power of all predators and parasites to the value of var(I) is 64.6%. The variances and covariances should be equal to zero if the affecting power of predators and parasites are made constant; the result of doing this shows that the change in var (I) is 96.5%. This result confirms the fact that. predators and parasites are the important factors for the population dynamics of the key generation. According to the, analysis, a control strategy is made for that generation.Predators and parasites are also key factors for the autumn generation. In contrast, the key factor in the first and second late autumn generations is weather.