不同牧草植物对草地螟产卵选择和种群增长的影响

Preferences of Loxostege sticticalis for oviposition on different pasture plants and the effects of different host plants on the population growth of this pest

【目的】明确不同产卵寄主植物对草地螟Loxostege sticticalis种群增长的影响。【方法】选用7种不同的供试牧草研究草地螟的产卵选择偏好;并比较取食不同牧草植物对草地螟生长发育、繁殖力和种群增长的影响。【结果】草地螟对豆科牧草的产卵偏好性显著高于禾本科牧草。草地螟在苜蓿、草木樨以及藜(对照)上的落卵量较多,落卵量百分比分别为17.45%、16.02%和24.87%。取食这3种植物的草地螟幼虫均可完成世代繁殖,种群增长指数分别为80.36、43.74和34.28,而取食其他牧草的幼虫不能完成世代繁殖。【结论】草地螟成虫对不同寄主植物的产卵偏好性差异显著,幼虫取食落卵量较高的寄主植物更有利于草地螟种群的增长和繁衍。

[Objectives]To determine the oviposition preferences of Loxostege sticticalis with respect to seven different pasture plants,and the effect of different host plants on the population growth of this pest.[Methods]The relative preference of L.sticticalis for oviposition on seven different pasture plants was determined,and the growth,development,fecundity and population growth of L.sticticalis on these different plants was measured and compared.[Results]There was a significant preference for leguminous grasses over gramineous grasses.The proportion of eggs laid on Medicago sativa,Melilotus officinalis,and Chenopodium album(control)was higher that on other plants;17.45%,16.02%,and 24.87%,respectively.Larvae that fed on these three plants were able to reproduce for generations,with population growth indices of 80.36,43.74,and 34.28,respectively,while those that fed on other pasture plants could not.[Conclusion]L.sticticalis prefers to oviposit on leguminous grasses,and these host plants are more conducive to the growth and reproduction of this pest.