Molecular and morphological identification of pistachio armored scale insects (Hemiptera: Diaspididae), with description of a new species.

Members of the family Diaspididae (Hemiptera: Coccomorpha) can be devastating pests that suck parenchyma cell contents from crops and cause severe damage to pistachio trees (Pistacia vera L.). The current research collected and characterized diaspidid species from pistachio orchards in Kerman province, Iran, according to their morphological and molecular features. Lepidosaphes pistaciae Archangelskaya, Suturaspis davatchi (Balachowsky & Kaussari) and Melanaspis inopinata (Leonardi) are redescribed and a new species, Melanaspis pistaciae Hosseininaveh & Kaydan sp. n., is described. Phylogenetic trees based on molecular analysis of COI and 28S rDNA fragments placed all the species in separated clades and confirmed M. pistaciae as a new taxon which is concluded by morphological differences. Molecular analysis suggests non-monophyly of the populations of each species. Melanaspis pistaciae sp. n. has spread to most cultivated pistachio areas in Iran and has probably been misidentified as M. inopinata in the past. Further investigation of the biology of this species may lead to development of more effective approaches for controlling this pest.

Digestive proteolytic activity in the Sunn pest, Eurygaster integriceps.

The Sunn pest, Eurygaster integriceps Puton (Heteroptera: Scutelleridae), is one of the most important pests of wheat and causes considerable damage to this valuable crop annually. Digestive proteinase activity of adult insects was investigated using general and specific substrates and inhibitors. Proteolytic activity was low when the common conventional substrates, azoalbumin, azocasein and hemoglobin were used to assay salivary glands and midguts. Using the fluorescent casein substrate (BODIPY FL casein), total proteolytic activity was measured at different pH. Maximum proteolytic activity was detected at pH 7 (100%) and 8(65%) which suggested the presence of serine proteinases in the salivary glands. There was no detectable proteolytic activity in midgut extracts. The inhibitors; PMSF (inhibitor of serine proteinases) and TPCK (a specific chymotrypsin inhibitor) showed greater than 50% inhibitory effect on total proteolytic activity, however, TLCK (specific trypsin inhibitor) and E-64(specific cysteine proteinase inhibitor) did not inhibit total proteolytic activity. Using fluorescent specific substrates for serine and cysteine proteinases (Z-Arg-AMC, Z-Arg-Arg-AMC, Z-Arg-Phe-AMC and Suc-Ala-Ala-Pro-Phe-AMZ) revealed the presence of tryptic and chymotryptic activity in the salivary gland extract. Zymogram analysis under non-reducing SDS-PAGE conditions and using the substrate APNE showed at least 8 tryptic and chymotryptic activity bands in salivary gland extracts. A single high molecular weight band with tryptic activity (165 kDa) was detected using the substrate BApNA in a zymogram analysis using native-PAGE. Kinetic studies showed a k(m) value of 0.6 mM for this enzyme against the substrate BApNA .The inhibitor TLCK decreased activity of the trypsin-like enzyme up to 73% and almost completely eliminated the only band related to this proteinase in the zymogram. Soybean Kunitz type trypsin inhibitor showed no effect on proteolytic activity of the trypsin-like serine proteinase. In general, the results revealed the presence of chymotrypsin- and trypsin-like serine proteinases in the salivary gland of E. integriceps, and it seems that the major total proteolytic activity is due to chymotrypsin proteinases.