不同品种玉米对草地贪夜蛾生长发育及繁殖的影响

为评价新入侵害虫草地贪夜蛾对我国不同品种玉米的为害潜能,本文采用组建实验种群生命表的方法研究了草地贪夜蛾对3种甜质型玉米(穗甜1号、正甜68和华金甜1号)以及3种糯质型玉米(京科糯2000、广黑甜糯和广糯1号)的生存适合度,分析了草地贪夜蛾生物学指标与玉米叶片主要营养物质及粗纤维含量间的相关性。结果表明: 取食甜质型玉米的草地贪夜蛾的幼虫存活率、蛹重、雌成虫产卵量均显著高于取食糯质型玉米;取食甜质型玉米草地贪夜蛾的内禀增长率介于0.1566～0.1843,净生殖力介于187.97～353.35,也均高于取食糯质型玉米(内禀增长率介于0.0998～0.1465,净生殖力介于25.89～95.34),表明取食甜质型玉米的草地贪夜蛾具有更高的种群增长能力。甜质型玉米叶片中主要营养物质维生素C、淀粉、可溶性糖、蛋白质、脂肪、总氨基酸及粗纤维的含量普遍高于糯质型玉米,草地贪夜蛾的净生殖力与维生素C、淀粉、可溶性糖、蛋白质及粗纤维的含量均存在显著正相关关系。草地贪夜蛾在甜质型玉米上具有更高的生存适合度。

Effects of different corn varieties on development and reproduction of Spodoptera frugiperda

To understand the damage capability of the invasive pest Spodoptera frugiperda on diffe-rent corn varieties in China, we evaluated survival fitness of S. frugiperda on three varieties of sweet corn (i.e., Suitian No.1, Zhengtian 68, and Huajintian No.1) and three varieties of waxy corn (i.e., Jingkenuo 2000, Guangheitiannuo, and Guangnuo No.1) by constructing life table for all populations. The correlation of biological parameters of S. frugiperda to the main nutrients and crude fiber content in corn leaves were analyzed. Results showed that the larva survival rate, pupal weight, and production of S. frugiperda on sweet corns were significantly higher than those on waxy corns. The intrinsic rate of increase (r_m) of S. frugiperda on the sweet corns ranged from 0.1566 to 0.1843, and the net reproductive rate (R₀) ranged from 187.97 to 353.35, being higher than those reared on the waxy corns (r_m was from 0.0998 to 0.1465, and R₀ was from 25.89 to 95.34). S. frugiperda reared on the sweet corns had higher population growth ability than those reared on the waxy corns. The content of main nutrients such as vitamin C, starch, soluble sugar, protein, fat, total amino acids, and crude fiber in the sweet corn leaves were higher than those in the waxy corn leaves. There were positive correlations between R₀ of S. frugiperda to the contenst of vitamin C, starch, soluble sugar, protein, and crude fiber in corn leaves. The results indicated that S. frugiperda reared on the sweet corn leaves had higher survival fitness than those reared on the waxy corn leaves.