Comparison of á and â-galactosidase activity in the three cereal pests, Haplothrips tritici Kurdjumov (Thysanoptera: Phlaeothripidae), Rhopalosiphum padi L. (Hemiptera: Aphididae) and Eurygaster integriceps Puton (Hemiptera: Scutelleridae)

Abstract : The Sunn pest, E. intergriceps, the bird cherry-oat aphid, Rhopalosiphum padi, and wheat thrips, H. tritici are the major pests of wheat and other cereals in a wide area of the world. All these three insect species could produce damage to the wheat, to some extent. So the aim of the current study was to determine the á and â-Galactosidase of the three mentioned insect pests. Thus, these insects were collected from the wheat farm and their guts (the Sunn pest and the aphid) were removed. However, regarding the thrips, because of the small body, whole body used in order to extract the enzymes. The enzymes, including á and â-galactosidase activity were measured by the hydrolysis of p-nitrophenyl-á-D-galactopyranoside (pNPáGal) and p-nitrophenyl-â-D-galactopyranoside (pNPâGal), respectively using phosphate citrate buffer (pH5.0). Galactosidases were active in all three insect species tested. However, there were significant differences in activities of the two enzymes tested. The greatest activities of the two enzymes, á- and â- galactosidases, were found in the Sunn pest, Eurygaster integriceps, and the least activities of the two tested enzymes, á- and â- galactosidases, were found in the aphid, Rhopalosiphum padi. Activities of the enzyme were modest in the thrips, Haplothrips tritici. The greatest amount of á- and â- galactosidases in the Sunn pest makes sense since the Sunn pest is the main pest in the wheat farm that can feed on wheat grains. In the wheat grains, the highest amount of glycoproteins and glycolipids are present. Thus, it has been known that these enzymes (á- and â- galactosidases) are active on digestion of glycoproteins and glycolipids
Keyword : Galactosidases, The Sunn pest, Wheat thrips, The bird cherry-oat aphid
Author(s) : , S. Seddigh, A. R. Bandani
Downloads : 1019

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