棉铃虫种群能量动态及其为害特征分析

根据棉铃虫种群数量密度、年龄结构、存活率及虫体含能量，系统地分析了８种不同类型棉田生态系统中棉铃虫种群生产力、摄入量及其为害特征．结果表明，棉铃虫种群的能量生产主要集中于第３代；其所引起棉花繁殖器官的被害量在第２、３、４代分别为１１．８３、１６．６５和９．５２个·ｍ－２．随着播种期的推后，２代棉铃虫种群生产力和摄入量减少，３、４代值增加．实行套作种植使２、４代值减少，而３代值增加．棉铃虫种群摄食利用效率随世代增加而减小，其净生态效率以第３代最高，第４代居中，第２代最小．由此进一步探讨了不同时空类型棉田棉铃虫各代管理的对策．

Energy dynamics of Heliocoparva armigeria population and its damage characteristics

Based on the population density, age structure, mortality and energy dynamics of Heliocoparva armigeria, its population production, ingestion and damage characteristics in eight different cotton field ecosystems are analysed. The results show that the energy production of H. armigeria population comes mainly from 3rd generation. The damaged amount of reproductive organs of cotton by the bollworm of 2nd, 3rd and 4th generations is respectively 11. 83, 16. 65 and 9. 52 boils. m- 2. Along with the delay of cotton planting , the population production and ingestion of 2nd generation H. armigeria are decreased, and those of 3rd and 4th generation are increased. When the cotton intercropping is implemented , those are decreased for 2nd and 4th generations, and are increased for 3rd one.The ingestion-utilization efficiency of bollworm is increased with its increasing generation and its net ecological efficiency is maximum in 3rd generation, medium in 4th one, and minimum in 2nd one. The management strategies for bollworm is discussed in this paper.