DIGESTIVE ENZYMES OF SIXTH-INSTAR LARVAE OF THE PALE WESTERN CUTWORM, AGROTIS ORTHOGONIA (LEPIDOPTERA: NOCTUIDAE)

Abstract

AbstractResults of a qualitative survey of some digestive enzymes of sixth-instar larvae of the pale western cutworm are reported. An extract prepared from the mesenteron (midgut) and its contents showed activity for the enzymes, proteinase, aminopeptidase, dipeptidase, amylase, α-glucosidasc, α-galactosidase, and lipase. There was also evidence for a β-glucosidase activity in the brei prepared from the mesenteron. A brei of salivary glands showed activities for α-glucosidase and amylase, as well as a strong proteinase. These enzymes were not found in brei prepared from the stomodaeum (foregut) or proctodaeum (hindgut). There was no evidence for polygalacturonase, celiulase, β-galactosidase, or carboxypeptidase in any part of the digestive system.Values of pH for extracts from the different parts of the digestive system were: proctodaeum, 7.2; mesenteron, 8.2; stomodaeum, 7.8; and salivary glands, 7.8.