Variations of glycosidase activity in the larva of Phoracantha semipunctata F. (Coleoptera Cerambycidae) submitted to 60Ca ioniziing radiation
Chararas, C.; Courtois, J.E.; Viard, B.
Comptes Rendus des Seances de la Societe de Biologie et de ses Filiales 168(2-3): 227-230
1974
ISSN/ISBN: 0037-9026 PMID: 4282278 Document Number: 71259
In further studies on the biology and nutrition of Phoracantha semipunctata (F.), fourth-instar larvae reared on Eucalyptus camaldulensis were treated with gamma -radiation from 60Co at rates of 2000 or 10 000 rad and allowed to resume feeding for 12 days; they were then dissected and their enzyme activity compared with that of untreated larvae. Irradiation caused a sharp reduction on cellulase activity but did not appreciably affect alpha - and beta -galactosidases or amylase in the directly extractable fraction; within the cells, no cellulase was detectable and there was a slight reduction in amylase and invertase. Tissue lesions were quite severe but did not develop until 16-18 days after irradiation. Changes occurred in the mucopolysaccharide, glycoprotein and mucoprotein content of treated as compared with untreated insects. All cellular activities appeared to be disturbed by irradiation, but most of the processes of glucoside breakdown were not. It is pointed out that the latter were not investigated until ten days after treatment and also that enzyme activity tends to be preserved when irradiation is carried out in the presence of the substrate.