عنوان مقاله [English]
نویسندگان [English]چکیده [English]
Melon ladybird, Epilachna chrysomelina (F.) is one of major pests of cucurbitaceous plants. Larvae and adults feed on host plants and cause serious damage to them. Study of the digestive enzymes is necessary for engineering resistant host plants to pests. By determination of the biochemical characteristics of the digestive carbohydrases, the necessary information can be supplied for application of resistant plants containing inhibitors. In the present study, biochemical properties of galactosidases were studied in the alimentary canal of melon ladybird. The measuring of the enzymes activity in the digestive system of the 2nd, 3rd and 4th instars, female and male adults showed that the highest specific activity of digestive enzymes was in the digestive system of the 3rd instar and the enzyme activities in the male and female digestive systems did not show any significant difference. The optimal pH and temperature for galactosidases activity in the alimentary canal were found to be 5 and 40°C, respectively. The Km values of α and β galactosidases in the gut of E. chrysomelina were 0.013 and 0.02 mM, respectively. The results of zymogram pattern in the native gel revealed that α- and β-galactosidases had one isoform in the alimentary canal of E. chrysomelina.