New occurrences of the ragweed leaf beetle (Ophraella communa LeSage, 1986) (Coleoptera, Chrysomelidae) in Hungary

Fifteen new occurrences of ragweed leaf beetle (Ophraella communa LeSage, 1986) are presented from Hungary based on targeted faunistic investigations and the results of our call for citizen scientists. All records are concentrated on the nearby regions of Budapest, suggesting that the species was introduced to this northern central region of the country by human activity. The high number of new occurrences indicates that the species is steadily established in this region. In contrast, the natural dispersal from the neighbouring southern countries seems not to cross the Hungarian borders yet.

Silencing the Myosin Regulatory Light Chain Gene sqh Reduces Cold Hardiness in Ophraella communa LeSage (Coleoptera: Chrysomelidae)

Ambrosia artemisiifolia is a noxious invasive alien weed, that is harmful to the environment and human health. Ophraella communa is a biocontrol agent for A. artemisiifolia, that was accidentally introduced to the Chinese mainland and has now spread throughout southern China. Recently, we found that upon artificial introduction, O. communa can survive in northern China as well. Therefore, it is necessary to study the cold hardiness of O. communa. Many genes have been identified to play a role in cold-tolerance regulation in insects, but the function of the gene encoding non-muscle myosin regulatory light chain (MRLC-sqh) remains unknown. To evaluate the role played by MRLC-sqh in the cold-tolerance response, we cloned and characterized MRLC-sqh from O. communa. Quantitative real-time PCR revealed that MRLC-sqh was expressed at high levels in the gut and pupae of O. communa. The expression of MRLC-sqh was shown to decrease after cold shock between 10 and 0 °C and ascend between 0 and −10 °C, but these did not show a positive association between MRLC-sqh expression and cold stress. Silencing of MRLC-sqh using dsMRLC-sqh increased the chill-coma recovery time of these beetles, suggesting that cold hardiness was reduced in its absence. These results suggest that the cold hardiness of O. communa may be partly regulated by MRLC-sqh. Our findings highlight the importance of motor proteins in mediating the cold response in insects.

Možnosti zatiranja izbranih plevelnih vrst v Evropi z žuželkami

Weed control by insects is increasingly important, as chemical weed control (the use of herbicides) has an important impact on the environment and, consequently, on all organisms living there. The use of insects to control weeds thus represents an alternative to herbicides. The article presents the suppression of some widespread and persistent weeds in Europe with their natural enemies - insects. The following combinations presented below are: broad-leaved dock (<em>Rumex obtusifolius</em> L.) – <em>Gastrophysa viridula</em> (De Geer, 1775), curly dock (<em>Rumex crispus</em> L.) – <em>Apion violaceum</em> (Kirby, 1808), common ragweed (<em>Ambrosia artemisiifolia</em> L.) – <em>Ophraella communa</em> (LeSage, 1986) and <em>Zygogramma suturalis</em> (Fabricius, 1775), creeping thistle (<em>Cirsium arvense</em> (L.) Scop.) – <em>Cassida rubiginosa</em> (Müller, 1776), cleavers (<em>Galium aparine</em> L.) – <em>Halidamia affinis</em> (Fallen, 1807) and <em>Sermylassa halensis</em> (Linnaeus, 1767), common knotgrass (<em>Polygonum aviculare</em> L.) and black-bindweed (<em>Fallopia convolvulus</em> L.) – <em>Gastrophysa polygoni</em> (Linnaeus, 1758) and as the last one field bindweed (<em>Convolvulus arvensis</em> L.) – <em>Galeruca rufa</em> (Germar, 1824) and <em>Tyta luctuosa</em> (Denis in Schiffmuller, 1775).