旋幽夜蛾对寄主植物选择偏好和种群适合度

Selection Preference and Population Fitness of Scotogramma trifolii to Different Host Plants

【目的】研究旋幽夜蛾对寄主植物的选择偏好和种群适合度,为旋幽夜蛾的生态防治提供理论依据。【方法】通过田间罩笼试验和室内饲养试验,调查产卵选择率、幼虫取食选择率、生长发育指标和种群参数。【结果】旋幽夜蛾成虫产卵选择率为灰藜>棉花>甜菜>白菜,幼虫取食选择性由高到低依次为甜菜>白菜>灰藜>棉花。参试4种寄主植物的幼虫历期由长到短为棉花>甜菜>白菜>灰藜,蛹历期为棉花>甜菜>灰藜>白菜。饲喂白菜、棉花比饲喂灰藜、甜菜的蛹质量稍重。饲喂4种寄主植物的孵化率为81.97%~87.26%,饲喂灰藜的幼虫存活率最高,为82.93%,饲喂棉花的幼虫存活率最低,为22.50%,饲喂棉花的蛹存活率最高,为100.00%,饲喂甜菜的蛹存活率最低,为82.36%,饲喂灰藜的羽化率最高,为91.36%,饲喂甜菜的羽化率最低,为71.38%。饲喂白菜的产卵量最高,为367.30粒/雌,饲喂棉花的产卵量最低,为274.70粒/雌。【结论】棉花、白菜、甜菜、灰藜均可作为旋幽夜蛾的寄主。灰藜、白菜、甜菜均为旋幽夜蛾的适宜寄主。灰藜是旋幽夜蛾最偏好选择产卵的寄主,甜菜、白菜是幼虫最偏好取食的寄主,旋幽夜蛾对寄主的产卵选择偏好与取食选择偏好存在差异。参试4种寄主饲喂旋幽夜蛾,各寄主间对卵历期、成虫历期和繁殖力、卵孵化率无显著影响,但对其幼虫历期、蛹历期、世代历期、幼虫存活率、蛹存活率、羽化率、蛹重存在显著影响,旋幽夜蛾对参试4种寄主植物的适合度存在一定差异。

【Objective】The purpose of this study was to provide a theoretical basis for ecological control and sustainable control of Scotogramma trifolii,in order to determine the selection preference of host plants and population fitness of Scotogramma trifolii.【Method】The oviposition selection rate,larval feeding rate,growth and development index and population parameters were investigated by field cage experiment and indoor feeding experiment.【Result】The oviposition selection rate of Scotogramma trifolii was Chenopodium album L.>cotton>sugar beet>Chinese cabbage,larva feeding selectivity from high to low was sugar beet>Chinese cabbage>Chenopodium album L.>cotton.The larval duration of the four host plants was cotton>sugar beet>Chinese cabbage>Chenopodium album L.,and pupal duration was cotton>sugar beet>Chenopodium album L.>Chinese cabbage.The pupa weight of Scotogramma trifolii fed with Chinese cabbage,cotton was slightly heavier than that fed with Chenopodium album L.,sugar beet.The hatching rates of Scotogramma trifolii fed with four host plants were between 81.97%and 87.26%.The larvae fed with Chenopodium album L.had the highest survival rate(82.93%),while those fed with cotton had the lowest survival rate(22.50%).The pupae of Scotogramma trifolii fed with cotton had the highest survival rate(100.00%),while those fed with sugar beet had the lowest survival rate(82.36%).The eclosion rate of Scotogramma trifolii fed with Chenopodium album L.was the highest(91.36%),while that fed with sugar beet was the lowest(71.38%).The fecundity of Scotogramma trifolii fed with Chinese cabbage was the highest(367.30 eggs/female),while those fed with cotton were the lowest(274.70 eggs/female).【Conclusion】Cotton,Chinese cabbage,sugar beet,and Chenopodium album L.are hosts of Scotogramma trifolii.Chenopodium album L,Chinese cabbage and sugar beet are the suitable hosts for Scotogramma trifolii.Chenopodium album L.is the most preferred host for oviposition,sugar beet and Chinese cabbage are the most preferred hosts for larval feeding.The oviposition preference of Scotogramma trifolii is not consistent with that of feeding choice.Feeding four hosts had no significant effect on egg duration,adult duration,hatching rate and fecundity,but had significant effect on larval duration,pupal duration,generation duration,larval survival rate,pupal survival rate,eclosion rate and pupa weight.There were some differences in the fitness of Scotogramma trifolii to different host plants.