SYNERGISTIC ACTION OF CHLORPYRIFOS-METHYL AND JUVENILE HORMONE ANALOGUE AGAINST LARVAL CARBOHYDRATE AND PHOSPHATASE BIOCHEMISTRY OF EPHESTIA CAUTELLA WALKER (LEPIDOPTERA: PYRALIDAE)

Abstract

Sub-lethal concentrations (i.e.1,2 and 4ppm) of a synergistic mixture chlorpyrifos-methyl + methoprene in the ratio of 9:1 when exposed to third instar larvae of almond moth, Ephestia cautella Walker caused a significantly dose-dependent ( p < 0.05) reduction in glycogen level and alkaline phosphatase activity and a significantly dosedependent ( p < 0.05) enhancement in the reducing sugar lavel and the activity of acid phosphatase. The highest concentration i.e. 4ppm of this mixture exerted severe effect on glycogen and reducing sugars level as well as on the activities of acid and alkaline phosphatases, which along with other perturbed biochemical parameters by this synergist leads to death of the larva.