玉米和小麦对黏虫生长发育和繁殖的影响

Effects of Maize and Wheat on the Development and Reproduction of Mythimna separata(Walker)

在室内温度15℃~25℃(平均18℃)、相对湿度70%、光周期12 L:12 D条件下,测定黏虫在玉米和小麦上各发育阶段的历期、存活率和产卵量,组建黏虫在两种寄主植物上的生命表。结果表明,与幼虫期取食小麦相比,取食玉米的幼虫发育历期极显著缩短(1.168±0.337)d;成虫产卵前期和产卵历期分别显著缩短和延长(1.063±0.435)d、(2.692±0.991)d;单雌平均产卵量增加240.533±153.965粒;蛹质量、世代存活率均明显提高。生命表参数表明,幼虫期取食玉米的黏虫种群净增殖率(R0)、内禀增长率(r_(m))和周限增长率(λ)分别为573.96、0.10和1.10,较取食小麦的高;平均世代周期(T)和种群加倍时间(td)分别为66.59和7.27,较取食小麦的低。黏虫的生长发育和繁殖在小麦和玉米间存在显著差异。与小麦相比,玉米更适宜黏虫的生长发育和繁殖,为近年来黏虫频繁在玉米上暴发成灾提供一定的理论依据。

The developmental duration,survival rate,reproduction,and age-stage life table of M.separata reared feeding on wheat and maize were carried out under laboratory conditions of 15℃-25℃(average18℃),RH 70%and a photo period of 12 L:12 D.The results showed that,compared with those fed on wheat,the developmen⁃tal duration,and the pre-oviposition period of M.separata fed on maize were significantly shortened 1.168±0.337 d and 1.063±0.435,respectively.The oviposition period per female was prolonged 2.692±0.991d.The oviposition quantity increased 240.533±153.965,and the pupae weight and the generation survival rate were significantly in⁃creased.The life table parameters indicated that the net reproductive rate(R0),intrinsic rate of increase(r_(m))and finite rate of increase(λ)of M.separata fed on maize were 573.96,0.10 and 1.10,which higher than those fed wheat(304.05,0.08 and 1.09).The mean generation time(T)and double population time(td)of M.separata fed on maize were 66.59 and 7.27,lower than those fed on wheat(67.37 and 8.17).The development and reproduction of M.sepa⁃rata reared on wheat and maize exhibited significant difference.Maize was more suitable for growth and develop⁃ment of M.separata than wheat,and this provided one of the possible reasons for the outbreak on a maize field.