关键词: 斜纹夜蛾, 寄主植物, 取食行为, 产卵行为, 选择

Abstract: Five large-scale planted crops (cotton, soybean, sweet potato, sesame and peanut) were selected to determine the larval feeding and egg-laying preference of Spodoptera litura using the dish-leaf and oviposition-in-cage methods,so as to provide theoretical basis for the host-transfer regularity,regional monitoring and integrative prevention & control system.The results showed that the 1st instar larvae maintained a high feeding rate on the leaves of cotton,soybean,sweet potato,sesame and peanut in the non-selective feeding experiment,and showed no obvious avoidance behavior.In the selective feeding
experiment,the feeding rate of the 1st instar larvae increased first with time elapsed, followed by a decrease on the leaves of cotton, soybean, sweet potato and sesame, while the feeding rate gradually decreased on the leaves of peanut.It was concluded that the 1st instar larvae preferred sweet potato leaves in terms of the leaf-feeding area,which was significantly higher than those of the other four host plants,and eating the least on peanut leaves.These results indicated that the S.litura larva presented different feeding preference to different host plants.The order of feeding preference was sweet potato>sesame>cotton,soybean>peanut.In the egg-laying preference experiment,female adults also showed significant
oviposition preference to five host plants.The number of eggs and egg masses were the largest on soybean(574.9 and 2.2,respectively),with the smallest number on peanut(36.7 and 0.6,respectively).The order of egg-laying preference was soybean>sweet potato>sesame>cotton>peanut.In conclusion,S.litura presents different feeding and oviposition preference to five host plants,and shows different behavioral rhythm.The order of larval feeding preference is inconsistent with that of adult oviposition preference.

Key words: Spodoptera litura, Host plant, Feeding behavior, Oviposition behavior, Selectivity