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本文应用生命表技术,通过对桔潜叶蛾(Phyllonistis CitrellaStainton)9个世代生命表资料的分析,探讨了桔潜叶蛾自然种群数量消长规律及其原因。结果表明,主导世代间种群数量变动的关键因子是作用于幼虫期的寄生蜂,(白星姬小蜂Elachenis Sp.)和捕食天敌(包括亚洲草蛉Chrysopa bonine-nis 中华草岭C.sinica、小花蝽Orius minutus)。在重庆地区,由于在该种群前六个世代期间,各死亡因子,特别是天敌因子作用甚微,种群趋势指数均大于1,从而导致种群数量迅速增长。此后,随着天敌因子作用的加强,种群趋势指数迅速降至1以下,种群数量急剧减少。研究结果显示,除捕食天敌外,主要死亡因子如叶片营养条件、病原微生物,寄生蜂的作用均具不同程度的密度依赖性,且是补偿不足的。
In this paper, life table techniques were used to analyze the laws of the population decline and the reasons of the natural population of the leaf miner through analyzing the life table data of nine generations of Phyllonistis citrella Stinton. The results showed that the key factors affecting the population variation between dominant generations were parasitic wasps (Elachenis Sp.) And predators (including C. sinensis, Orius minutus). In Chongqing, due to the small effect of each factor of death, especially natural enemy factor, the tendency index of the population is greater than 1 during the first six generations of the population, resulting in rapid population growth. Since then, with the enhancement of the natural enemy factor, the population trend index rapidly dropped below 1, and the number of the population decreased sharply. The results showed that, except predation of natural enemies, the main factors of death, such as leaf nutrient conditions, pathogenic microorganisms, parasitoids, have different degrees of density dependence and are undercompensated.