【目的】在室内研究茉莉酸( JA)诱导青杨抗性对感染舞毒蛾核型多角体病毒( LdNPV)舞毒蛾幼虫生长发育及食物利用的影响，揭示舞毒蛾种群动态与核型多角体病毒病及寄主植物诱导抗性的关系。【方法】人工食料饲养到2龄的舞毒蛾幼虫，采用食料给毒法每头接 LdNPV 92 OBs·μL －1，然后分别接到茉莉酸诱导1，5，10天后的青杨苗木及未诱导过的青杨苗木上继续饲养，以不接病毒及未诱导的青杨苗木为对照组，待幼虫脱皮到3龄时称体质量、测量食叶量、排粪量，计算食物利用率等指标，记录发育历期。【结果】感染LdNPV舞毒蛾幼虫生长发育及食物利用受到其取食寄主植物诱导抗性的影响，幼虫感染 LdNPV 并取食 JA 诱导的青杨叶片(即 JA +V 组)，其发育历期、体质量、相对生长率及食物利用指标均比单独病毒感染的(即 V组)及对照 CK组显著降低，幼虫感染病毒并取食诱导1，5，10天青杨叶片的发育历期分别比 CK 组的延长1.0，1.2，1.7天；体质量分别比 CK 组降低27.8%，37.9%，34.3%，比 V组降低11.8%，18.2%和14.4%；相对生长率比 CK 组分别降低46.3%，58.1%和58.8%，比 V组分别降低20.7%，28.5%，26.6%；消化率、利用率、转化率均降低，3种处理从大到小的顺序为 CK组＞V组＞JA+V组；病毒感染的舞毒蛾幼虫取食量与对照差异不显著，病毒感染且取食 JA诱导5天青杨组的幼虫取食量与对照差异显著，可能与诱导5天青杨组叶片酚类等次生物质含量较高有关。【结论】JA 诱导青杨抗性增强了 LdNPV对舞毒蛾幼虫生长发育和食物利用的抑制作用。%Objective]This study aims to reveal the relationship of population dynamics of gypsy moth ( Lymantria dispar ) with nucleopolyhedrovirus ( NPV ) and induced-resistance of host plant. [Method] The effects of induced resistance of the green poplar (Populus cathayana) by jasmonic acid (JA) on development and nutritional utilization of gypsy moth larvae infected with and without LdNPV( Lymantria dispar nucleopolyhedrovirus) were studied in laboratory. Gypsy moth larvae were reared with artificial diets to the second instar and inoculated using a modified version of the diet plug method with 92 OBs·μL -1 of LdNPV each larva. Larvae that had consumed the entire plugs were transferred to the green poplar seedlings induced with jasmonic acid or the normal green poplar seedlings ( not induced with jasmonic acid) and fed on the seedlings up to the 3 rd instar. Larvae without inoculation with LdNPV and feeding on normal green poplar seedlings served as control. Larval body weight,leaves consumption,amount of feces were measured and efficiency of conversion of digested food of gypsy moth larvae were calculated,as well as the developmental duration was recorded.[Result]Larval development and nutritional utilization of gypsy moth were effected by LdNPV and the green poplar induced resistance by jasmonic acid ( JA) . The developmental duration,the relative growth rate,food utilization index of the group JA + V ( larvae infected with LdNPV and fed on green poplar induced by JA ) were decreased significantly compared with both the group V ( larvae infected with LdNPV but fed on leaves of the green poplar) and the group CK ( normal larvae fed on leaves of the green poplar) . The larval developmental duration of the group JA +V was longer for 1. 0 day,1. 2 day and 1. 7 day than that of the group CK when fed on the poplar after JA inducing 1day,5 days and 10 days,respectively. Larval weight of the group JA +V after induced 1 day,5 days and 10 days decreased by 27. 8%, 37. 9% and 34. 3%,respectively,compared with the group CK,by 11. 8%,18. 2% and 14. 4%,respectively, compared with the group V. The relative growth rates of the group JA +V after JA inducing 1day,5 days and 10 days decreased by 46. 3%,58. 1% and 58. 8%,respectively,compared with the group CK,by 20. 7%,28. 5% and 26. 6%, respectively,compared with the group V. The approximate digestibility,the efficiency of conversion of ingested food, efficiency of conversion of digested food of the group JA+V and the group V reduced compared with the group CK,and the rank of three group was the group CK>the group V> the group JA+V. The food consumption of the group V is not differ significantly from that of the group CK. The food consumption of the group JA+V differed significantly from that of the group CK only when JA inducing 5 days.[Conclusion]The results suggested that induced resistance of poplar by exogenous JA may enhance the negative effects of NPV on development and the nutritional utilization of gypsy moth larvae.
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