Insect midgut proteases are excellent targets for insecticidal agents such as protease inhibitors. These inhibitors are used for producing transgenic plants, resistant to pests. For achieving this goal, it is necessary to find the nature of specific proteases and their properties for adopting possible pest management procedure. Therefore, characterisation of the enzymes in the gut of the rose sawfly, Arge rosae (Hymenoptera: Argidae), responsible for proteolysis, was performed using a range of synthetic substrates and specific inhibitors. The optimum conditions for general proteases and trypsin were achieved at pH 10. The highest activity for general proteases was obtained at a temperature of 458C. The use of specific inhibitors and SDS-PAGE (sodium dodecyl sulfate polyacrylamide gel electrophoresis) provided evidence to suggest that most of the proteases belonged to the serine group because of high inhibitory effect of phenyl methane sulfonyl fluoride on total proteolytic activity. Also, inhibition assays and zymogram analysis showed that metalloproteases are present in A. rosae digestive system. These results indicated that A. rosae larvae mainly used serine proteases for protein digestion, with chymotrypsin as the dominant form. The kinetic parameters of trypsin-like proteases using N-benzoyl-DL-arg-p-nitroanilide as substrate indicated that the K m and V max values of trypsin in the gut of the fifth instar larvae were 730 + 17.3 mM and 456 + 13.85 nmol min 71 mg 71 protein, respectively.

Bark and ambrosia beetles from the subfamily Scolytinae are among the most important pests in forests of Northern Iran. During investigations conducted in 2013-2016 in different parts of northern forests, the species Crypturgus cribrellus Reitter, Liparthrum bartschti Mühl, Scolytus varshalovitchi Michalski, Scolytus sulcifrons Rey, Scolytus triarmatus (Eggers) and Trypophloeus granulatus (Ratzeburg) were recorded for the first time in Iran; Trypophloeus and Liparthrum were new genera for Iran. As new host plants we found Zelkova sp. for Scolytus varshalovitchi, Michalski, Populus sp. for Liparthrum bartschti, Mühl, Alnus sp. and Pterocarya fraxinifolia for Taphrorychus lenkoranus Reitter, Pterocarya fraxinifolia for Ernoporicus caucasicus (Lindemann), Carpinus sp. for Pteleobius vittatus (Fabricius), Parrotia persica for Scolytus intricatus (Ratzeburg), Alnus sp. and Pterocarya fraxinifolia for Hypothenemus eruditus (Westwood).

Saproxylic beetles play a vital role in conservation as indicators of the status of unmanaged forests. In light of the concern regarding the adverse impact of anthropogenic pressure on biodiversity, an essential step in forest conserva-tion strategy is the identification of saproxylic beetles. The Hyrcanian forests are a unique remnant of natural broadleaf temperate forests, with an evolutionary history that can be traced to the Tertiary and a high diversity tree species. Here we present the first checklist of saproxylic beetles in the Hyrcanian forests, including 398 species of saproxylic beetles, belonging to 207 genera and 46 families, identified by us. Based on our results and literature data, at least 670 saproxylic beetles occur in the Hyrcanian forests. The bias in our results towards some families supports the view that the detection of additional species can be expected, particularly from the forests with a greater diversity of tree species.

Molecular identification is going to be more widespread in taxonomic studies of insects when traditional tools are problematic and time consuming. Identification of bark beetles, as one of the most important pests of forests, based on morphological characteristics is difficult because of their small size and morphological similarities. In the current study, species-specific primers were desi gned to identify two most abundant and morphologically similar bark beetle species <em>Scolytus ensifer</em> Eichhoff 1881 and <em>S. ecksteini</em> Butovitsch 1929, both found on <em>Ulmus minor</em> Miller in north of Iran. These species-specific primers successfully produced a fragment size with 318 bp and 465 bp of mitochondrial cytochrome oxidase 1 (<em>CO1</em>) gene in <em>S. ensifer </em>and<em> S. ecksteini</em> respectively. The results revealed tha t the multiplex polymerase chain reaction using the species-specific primers could amplify a unique band to distinguish these two species so confirmed this method as a convenient and quick tool to identify those two bark beetle species.