elm leaf beetle, xanthogaleruca luteola, is a serious pest (particularly at its larval stage) of elm trees in many areas. the existence of three important enzyms namely: ?-amylase, ?- glucosidase and ?-glucosidase in the midgut of the insect at its larval stage was investigated. optimum activity for ?-, ?-glucosidase and ?-amylase was recorded at phs 5.0, 6.0 and 6.0 against p-nitrophenyl-?-d-g...

the leopard moth, zeuzera pyrina, is a key and worldwide pest damaging walnut as well as many other fruit trees during the larval stages. larvae were collected from infested twigs of walnut trees. midguts from larvae were removed under a stereomicroscope and their homogenates used as the enzyme source. larval midgut extracts showed an optimum activity at ph 8.0, 6.0 and 6.0 for ?-amylase, ?- an...

the imported willow leaf beetle, plagiodera versicolora is one of the main pests of forest trees worldwide including iran. activities of α- and β-glucosidases in the midgut of p. versicolora adults were studied in this research. the results showed a higher α- glucosidase activity of adultsthan β-glucosidase. the optimal phs for α- and β-glucosidases activities were found to be 6 and 9, respecti...

a study of insect digestive enzymes makes sense given that the gut is the major interface between the insect and its environment. an understanding of gut and digestive enzyme function is essential when advanced methods of insect management such as application of enzyme inhibitors and transgenic plants are developed to control insect pests. the aim of the current research project was to study mi...

1. Carbonic anhydrase was measured in tissues of silkmoths, Hyalophora cecropia, reared on either a wheatgerm-based synthetic diet or wild cherry foliage in feeding fifth-instar larvae, throughout the larval-pupal transformation and in newly ecdysed pupae. 2. Carbonic anhydrase activity was present in fat body, midgut and intgeumentary epithelial cells, but not in haemolymph, cuticle or the int...

The evolutionary plant-herbivore arms race sometimes gives rise to remarkably unique adaptation strategies. Here we report one such strategy in the lepidopteran herbivore Manduca sexta against its hostplant Nicotiana attenuata's major phytotoxins, 17-hydroxygeranyllinalool diterpene glycoside, lyciumoside IV and its malonylated forms. We show that alkalinity of larval regurgitant non-enzymatica...

The number of insect midgut cells is maintained homeostatically in vivo and in vitro. However, during starvation, the midgut shrinks and the rate of cell replacement appears to be suppressed. When they undergo metamorphosis, the internal organs of insects are drastically remodeled by cell proliferation, differentiation, and apoptotic processes, and the net number of cells usually increases. An ...

abstract because of relation between digestive enzyme activity and feeding of insects that directly is in relation with the damage of insects; studying digestive enzyme systems is important in finding new control methods based on inhibiting digestive enzyme activity. recently using transgenic plants containing enzyme inhibitors is important in improving resistance of crops to pests because of s...