Monitoring of Resistance to New Chemistry Insecticides in Spodoptera litura (Lepidoptera: Noctuidae) in Pakistan.

The armyworm Spodoptera litura (F.) is a very serious pest of many crops, vegetables, and ornamentals. Due to persistent application of insecticides, this pest has developed resistance to conventional as well as new chemistries. The present studies investigated the level of resistance to new chemistry insecticides, having novel modes of action, in the Pakistani field populations of S. litura during 1997-2010 by using a leaf-dip bioassay. Generally, a low to moderate resistance was recorded to indoxacarb, abamectin, fipronil, and methoxyfenozide; along with a very low resistance to spinosad. Resistance to emamectin benzoate, chlorfenapyr, and lufenuron was none or very low, in spite of their intensive use against S. litura. The insecticides, showing no or very low resistance, can be used in rotation in conjunction with other integrated pest management tactics to manage insecticide resistance in S. litura.