Digestive enzymes level in the midgut ofAdoretus lasiopygus Burmeister (Scarabaeidae: Coleoptera)
Enzyme system pertaining to the midgut region ofAdoretus lasiopyous Burm. is studied in vitro. Most of the carbohydrases operate optimally in the mesomesenteron whereas proteinases and lipases behave optimally in the metamesenteron region. Optimum conditions of certain carbohydrases in relation to pH, temperature, substrate concentration and enzyme concentration have been studied. α-amylase, α-glucosidase, β-glucosidase, α-galactosidase and β-galactosidase showed optimum activity at pH 5·7, 6·2, 5·0, 5·8 and 5·6 respectively, α-Amylase, α-glucosidase and α-galactosidase are physiologically adapted to high temperature ranging between 48°–62°C. A positive response of starvation on the secretion of cellulase, inulinase, α-and β-galactosidase is observed. Based on this parameter the midgut enzymes of the pest is divided into two groups i.e. enzymes secreted continually and those secreted under the influence of food.