草地贪夜蛾取食不同植物后生长发育及繁殖情况比较

Study on the growth development and reproductive ability of Spodoptera frugiperda fed with different plants

在室内研究草地贪夜蛾幼虫取食甘薯、谷子、狗尾草、高粱、水稻5种植物叶片后的生长发育及繁殖情况,组建了实验种群生命表。通过研究发现,取食不同植物的处理间,草地贪夜蛾卵孵化率的差异不显著,而其未成熟历期的差异显著:谷子<高粱<狗尾草<水稻<甘薯,5幼虫体重的差异显著:水稻<甘薯<狗尾草<谷子<高粱,蛹重差异显著:水稻<高粱<狗尾草<甘薯<谷子。取食甘薯、谷子和高粱后,末幼虫有6、7两个期;取食狗尾草后有6、7、8三个期;取食水稻后有7、8、9三个期;处理间世代存活率排序为狗尾草<水稻<高粱<甘薯<谷子。处理间单雌平均产卵量排序为水稻<狗尾草<甘薯<高粱<谷子;草地贪夜蛾取食甘薯、谷子、狗尾草、高粱、水稻叶片后的净增殖率R0分别为271.56、467.80、116.24、364.26、82.42,内禀增长率rm分别为0.12、0.17、0.12、0.17、0.09。综合上述结果得出,草地贪夜蛾在5种供试植物上均能实现种群繁殖,谷子和高粱是其适宜寄主,甘薯和狗尾草次之,水稻的适宜性相对较低。

The growth,development,and reproduction of Spodoptera frugiperda larvae fed on leaves of sweet potato,millet,green foxtail,sorghum,and rice were studied under indoor conditions,and an experimental population life table was assembled.The results showed that there were no significant differences in the egg hatching rates of S.frugiperda fed on different plants.However,there was a significant difference in the immature period duration:millet-fed group<sorghum-fed group<green foxtail-fed group<rice-fed group<sweet potato-fed group.The weight of the 5th instar larvae exhibited a significant difference:rice-fed group<sweet potato-fed group<green foxtail-fed group<millet-fed group<sorghum-fed group.Following the consumption of sweet potato,millet,and sorghum,the mature larvae had two instars,the 6th and the 7th instars.In contrast,the mature larvae that fed on green foxtail had three instars,the 6th,7th,and 8th.There were 7th,8th,and 9th instars of mature larvae feeding on rice.The intergenerational survival rate was in the order of green foxtail-fed group<rice-fed group<sorghum-fed group<sweet potato-fed group<milletfed group.The average number of eggs laid per female among treatments was in the order of rice-fed<green foxtailfed<sweet potato-fed<sorghum-fed<millet-fed.The net reproductive rates(R0)after feeding five plants were 271.56,467.80,116.24,364.26,and 82.42,respectively,and the intrinsic rates(rm)were 0.12,0.17,0.12,0.17,and 0.09,respectively.In summary,under the present experimental conditions,S.frugiperda could establish populations on all five plants tested.Millet and sorghum were suitable hosts,followed by sweet potato and green foxtail,and rice was relatively less suitable for it.