Lacey Lawrence A, Neven Lisa G, Headrick Heather L, Fritts Robert
Yakima Agricultural Research Laboratory, USDA-ARS, 5230 Konnowac Pass Rd., Wapato, WA 98951, USA.
J Econ Entomol. 2005 Dec;98(6):1863-9. doi: 10.1603/0022-0493-98.6.1863.
Fruit bins infested with diapausing codling moth larvae, Cydia pomonella (L.), are a potential source of reinfestation of orchards and may jeopardize the success of mating disruption programs and other control strategies. Entomopathogenic nematodes (EPNs) were tested as a potential means of control that could be applied at the time bins are submerged in dump tanks. Diapausing cocooned codling moth larvae in miniature fruit bins were highly susceptible to infective juveniles (IJs) of Steinernema carpocapsae (Weiser) and Steinernema feltiae (Filipjev) in a series of experiments. Cocooned larvae are significantly more susceptible to infection than are pupae. Experimental treatment of bins in suspensions of laboratory produced S. feltiae ranging from 10 to 100 IJs/ml of water with wetting agent (Silwet L77) resulted in 51-92% mortality. The use of adjuvants to increase penetration of hibernacula and retard desiccation of S. feltiae in fruit bins resulted in improved efficacy. The combination of a wetting agent (Silwet L77) and humectant (Stockosorb) with 10 S. feltiae IJs/ml in low and high humidity resulted in 92-95% mortality of cocooned codling moth larvae versus 46-57% mortality at the same IJ concentration without adjuvants. Immersion of infested bins in suspensions of commercially produced nematodes ranging from 10 to 50 IJs/ml water with wetting agent in an experimental packing line resulted in mortality in cocooned codling moth larvae of 45-87 and 56 - 85% for S. feltiae and S. carpocapsae, respectively. Our results indicate that EPNs provide an alternative nonchemical means of control that could be applied at the time bins are submerged in dump tanks at the packing house for flotation of fruit.
装有滞育苹果蠹蛾幼虫（苹果小卷蛾，Cydia pomonella (L.)）的果箱是果园再次遭受虫害的潜在源头，可能会危及交配干扰计划及其他防治策略的成效。昆虫病原线虫（EPNs）被作为一种潜在的防治手段进行测试，可在果箱被浸没于倾倒池时施用。在一系列实验中，微型果箱中处于滞育期且结茧的苹果蠹蛾幼虫对斯氏线虫（Steinernema carpocapsae (Weiser)）和长尾斯氏线虫（Steinernema feltiae (Filipjev)）的感染性幼虫（IJs）高度敏感。结茧幼虫比蛹对感染的敏感性显著更高。用实验室生产的斯氏长尾线虫悬浮液（浓度为每毫升水含10至100条IJs，并添加湿润剂（Silwet L77））对果箱进行实验处理，导致51%至92%的死亡率。使用佐剂来增强线虫对越冬虫茧的穿透能力并延缓斯氏长尾线虫在果箱中的干燥，可提高防治效果。在低湿度和高湿度条件下，将湿润剂（Silwet L77）和保湿剂（Stockosorb）与每毫升含10条斯氏长尾线虫IJs混合使用，导致结茧苹果蠹蛾幼虫的死亡率达到92%至95%，而在相同IJs浓度但不添加佐剂的情况下，死亡率为46%至57%。在实验包装线上，将受侵染的果箱浸入每毫升水含10至50条IJs且添加湿润剂的商业化生产线虫悬浮液中，斯氏长尾线虫和斯氏线虫分别导致结茧苹果蠹蛾幼虫的死亡率为45%至87%和56%至85%。我们的结果表明，昆虫病原线虫提供了一种替代性的非化学防治手段，可在果箱在包装厂被浸没于倾倒池以进行水果浮选时施用。
