两种昆虫病原线虫防治核桃云斑天牛田间效果评价

云斑天牛Batocera lineolata Chevrolat是核桃树的严重蛀干害虫，隐蔽性强，化学、物理防治方法难以奏效，昆虫病原线虫可以主动寻找寄主并在蛀道内建立种群，省工长效。本研究评价了不同剂量（250、500、1000、2000和4000 IJs/mL）的2种昆虫病原线虫（小卷蛾斯氏线虫Steinernema carpocapsae和嗜菌异小杆线虫Heterorhabditis bacteriophora）对核桃云斑天牛卵和幼虫的防治效果。结果表明，2种线虫对天牛卵和幼虫的最终防控效果随施用剂量增大而增强。施用剂量为4000 IJs/mL的小卷蛾斯氏线虫和嗜菌异小杆线虫对该天牛卵的校正防治效率分别达65.0%和39.5%，对幼虫的最终校正防治效率分别达93.8%和82.4%；2种线虫在2000 IJs/mL剂量下对天牛卵的校正防治效率分别达48.8%和32.3%，对幼虫的校正防治效率分别达85.9%和83.4%。从而说明，适宜剂量的昆虫病原线虫对云斑天牛幼虫的田间防控效果好于对卵的效果，可以作为云斑天牛的有效防治技术。

Evaluation of Two Entomopathogenic Nematode Species for Control of Batocera lineolata on Walnut Trees

Safe and effective tactics are needed for control of the white-striped longhorn beetle, Batocera lineolata, an important wood borer of walnut Juglans regia trees in Southwestern China. Two entomopathogenic nematode (EPN) species, Steinernema carpocapsae and Heterorhabditis bacteriophora were tested for their ability to control eggs and larvae of B. lineolata in a gel formulation. Five concentrations (250, 500, 1000, 2000 and 4000 IJs/mL) of these two EPN species were applied in this study. Results showed that the control efficiencies of the two EPNs on eggs and larvae of B. lineolata increased with increasing in their concentrations. The two EPN species could infect the beetle eggs and larvae but beetle mortality was higher for S. carpocapsae. At the concentration of 4000 IJs/mL, the corrected control efficiency of S. carpocapsae and H. bacteriophora were 65.0% and 39.5% against B. lineolata eggs, respectively; 93.8% and 82.4% against B. lineolata larvae, respectively. At the concentration of 2000 IJs/mL, the corrected control efficiency of S. carpocapsae and H. bacteriophora were 48.8% and 32.3% against eggs, respectively; 85.9% and 83.4% against larvae, respectively. It is concluded that the two EPNs when applied at suitable dosage were more effective against larvae than against eggs of B. lineolata and could be an effective control measure for B. lineolata.