取食不同食物的草地貪夜蛾的過冷卻點和結(jié)冰點

張悅 鄧曉悅 張雪艷

摘要 為探明草地貪夜蛾的抗寒能力及取食不同寄主植物對其抗寒能力的影響，本試驗對取食人工飼料及小麥、玉米和高粱等三種不同寄主植物的草地貪夜蛾部分蟲態(tài)的過冷卻點和結(jié)冰點進行了測定。試驗結(jié)果表明：人工飼料飼養(yǎng)的草地貪夜蛾不同蟲態(tài)間過冷卻點和結(jié)冰點存在顯著差異，其中蛹的過冷卻點和結(jié)冰點最低，分別為（-16.71±0.26）℃和（-5.04±0.21）℃，顯著低于其他蟲態(tài);3～6齡幼蟲的過冷卻點和結(jié)冰點隨齡期增大而升高。取食3種不同寄主植物的草地貪夜蛾蛹的過冷卻點和結(jié)冰點顯著低于幼蟲和成蟲。在不同寄主植物之間，取食玉米的草地貪夜蛾蛹的過冷卻點最低。除取食高粱的4齡幼蟲外，取食3種寄主植物的幼蟲的過冷卻點均隨齡期增大而升高。取食3種寄主植物的雌成蟲過冷卻點無顯著差異，但取食高粱的雄成蟲過冷卻點顯著低于取食小麥的。

關(guān)鍵詞 草地貪夜蛾; 過冷卻點; 結(jié)冰點; 寄主植物

中圖分類號： S 435.132 ?文獻標識碼： A ?DOI： 10.16688/j.zwbh.2019608

Abstract In order to understand the cold resistance of Spodoptera frugiperda and the effects of different host plants on their cold resistance， the supercooling point and the freezing point of S. frugiperda fed on artificial diet and three different host plants including wheat， corn and sorghum were measured. The results showed that the supercooling points and the freezing points of S. frugiperda at different developmental stages were significantly different when fed on artificial diet， and the pupa possessed the lowest supercooling point and freezing point， which were （-16.71±0.26）℃ and （-5.04±0.21）℃， respectively. The supercooling point and freezing point of larva increased with the instars. The pupa also showed the lowest supercooling point and freezing point compared to other developmental stages when reared on three different host plants. Among different hosts， the pupa developed on corn showed the lowest supercooling point. The supercooling point of larvae feeding the three hosts increased with the instars except the 4th instar on sorghum. The supercooling points of the female adult developed on three hosts showed no significant difference， but the male adult developed on sorghum had a significantly lower supercooling point than that on wheat.

Key words Spodoptera frugiperda; supercooling point; freezing point; host plant

草地貪夜蛾Spodoptera frugiperda （J.E.Smith）屬鱗翅目Lepidoptera夜蛾科Noctuidae，是一種原產(chǎn)于美洲熱帶和亞熱帶地區(qū)的重大遷飛性害蟲[1-3]。草地貪夜蛾具多食性和暴食性，喜食禾本科，可為害玉米、小麥、高粱、水稻在內(nèi)的353種植物，已在多個國家造成了嚴重的經(jīng)濟損失[4-5]。2019年1月草地貪夜蛾首次入侵我國云南，截至9月17日已入侵我國25個省區(qū)，為害面積高達16.4萬hm2[6]。草地貪夜蛾是否能在我國越冬、定殖以及是否成為我國常發(fā)性害蟲是我國未來植物保護工作的重點。……