摘  要  【目的】 探讨昆虫病原线虫对番茄潜叶蛾Tuta absoluta的侵染致死效果。【方法】 采用生物测定法分别评估5种昆虫病原线虫Steinernema carpocapsae All、S. longicaudum X-7、S. feltiae SN、Heterorhabditis bacteriophora H06和H. indica LN2在培养皿中对番茄潜叶蛾2龄幼虫、4龄老熟幼虫及蛹的毒力效果，并进一步测定了高毒力线虫在模拟生境条件（寄主植物叶片和土壤中）下对以上虫态的致死作用。【结果】 在培养皿中，剂量为10 IJs/虫测定条件下，5种昆虫病原线虫对番茄潜叶蛾2龄幼虫和4龄老熟幼虫表现出高毒力，处理72 h，2龄幼虫和4龄老熟幼虫的校正死亡率分别为≥ 88.33%和100.00%；斯氏线虫对蛹的敏感性优于异小杆线虫，其中S. carpocapsae All和S. longicaudum X-7对蛹的校正死亡率分别为81.25%和70.73%，显著高于H. bacteriophora H06（62.50%）和H. indica LN2（52.08%）（F = 6.702，df = 4, 20，P < 0.001）。在模拟生境中，剂量为10 IJs/cm²测定条件下，5种昆虫病原线虫对叶片中2龄幼虫72 h的校正死亡率为100%；剂量为15 IJs/cm²时，5种线虫对土壤中4龄老熟幼虫72 h的校正死亡率为100%，且S. carpocapsae All对土壤中蛹的防治效果最好，侵染致死率达79.17%，显著优于S. longicaudum X-7（64.58%）和S. feltiae SN（62.50%）（F = 10.176，df = 2,12，P = 0.003）。【结论】 S. carpocapsae All、S. longicaudum X-7、S. feltiae SN、H. bacteriophora H06和H. indica LN2对叶片中番茄潜叶蛾幼虫高度敏感，可进一步研究其田间防控效果，并可通过研发和利用叶面保护剂稳定或增强线虫叶面防效；S. carpocapsae All针对土壤中4龄老熟幼虫和蛹的侵染致病效果最好，可有效防控番茄潜叶蛾土壤隐蔽虫态。

Abstract  [Aim]  To examine the effect of infection of the 2nd and 4th instar larvae and pupae of Tuta absoluta by entomopathogenic nematodes (EPNs). [Methods]  The pathogenicity of five EPNs, Steinernema carpocapsae All, S. longicaudum X-7, S. feltiae SN, Heterorhabditis bacteriophora H06 and H. indica LN2, to 2nd and 4th instar mature larvae and pupae were determined using bioassays. [Results]  In a petri dish bioassay, infection with the five EPNs (10 IJs/insect) resulted in ≥ 88.33% and 100.00% corrected mortalities of the 2nd and 4th instar larvae after 72 h. Infection with Steinernema spp. was relatively virulent to pupae compared to Heterorhabditis spp. Significantly higher corrected mortalities of pupae (81.25% and 70.73%) were caused by S. carpocapsae All and S. longicaudum X-7 at a dosage of 10 IJs/insect compared to the same dosage of H. bacteriophora H06 (62.50%) and H. indica LN2 (52.08%) (F = 6.702; df = 4, 20; P < 0.001). Under simulated conditions, 100% corrected mortality of the 2nd instar larvae on leaves were caused by infection with the five EPNs at a dosage of 15 IJs/cm² after 72 h. Infection with the five EPNs at a dosage of 15IJs/cm² also resulted in 100% corrected mortality of 4th instar larvae in soil were after 72 h. Infection with S. carpocapsae All at a dosage of 20 IJs/cm² caused significantly higher corrected mortalities (79.17%) of pupae in soil than infection by S. longicaudum X-7 (64.58%) and S. feltiae SN (62.50%) (F = 10.176; df = 2,12; P = 0.003). [Conclusion]  Steinernema carpocapsae All, S. longicaudum X-7, S. feltiae SN, H. bacteriophora H06, H. indica LN2 are highly virulent to T. absoluta larvae on leaves, which could be used to evaluate their efficacy as biological controls for this pest in the field. Leaf surface protectants can be developed to stabilize or enhance the efficacy of EPNs applied to leaves. Infection with S. carpocapsae All resulted in higher corrected mortalities of 4th instar larvae and pupae in soil than infection by S. longicaudum X-7 and S. feltiae SN, which suggests that S. carpocapsae All has the potential to control T. absoluta in soil.