TY - JOUR A1 - Takov, Danail A1 - Pilarska, Daniela A1 - Linde, Andreas A1 - Barta, Marek T1 - Infectious and parasitic diseases of phytophagous insect pests in the context of extreme environmental conditions JF - Central European Forestry Journal N2 - The density of phytophagous insect pest populations is related (directly and indirectly) to several groups of factors that can be broadly divided into: abiotic, biotic and anthropogenic. Each extreme in the abiotic environment at a macro-level leads to a series of consecutive extremes in the biotic environment, which eventually results in micro-level responses in the individual organisms. The manifestation of factors acts in aggregate or in a sequence, creating a chain of processes around us. Insects very efficiently use the abundance of nutritional resources, resulting in a tremendous increase in their population density, and triggering control mechanisms through the emergence of parasitic and pathogenic infections (viruses, bacteria, fungi, microsporidia, protozoa and nematodes). The development of entomopathogenic infections in host populations is directly dependent on the characteristics of both the antagonist and the insect. It is associated with the lifestyle and life cycle of the insect, with features encoded in the mechanism of pathogen action, and limited by the pathogen’s virulence and pathogenicity. KW - Entomopathogenic infections KW - Environmental conditions KW - Extreme KW - Insect pests KW - Epizootic Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:eb1-opus-2541 SN - 2454-0358 VL - 67 IS - 2 SP - 72 EP - 84 PB - Sciendo ER - TY - JOUR A1 - Kovač, Marta A1 - Linde, Andreas A1 - Lacković, Nikola A1 - Bollmann, Friedrich A1 - Pernek, Milan T1 - Natural infestation of entomopathogenic fungus Beauveria pseudobassiana on overwintering Corythucha arcuata (Say) (Hemiptera: Tingidae) and its efficacy under laboratory conditions JF - Forest Ecology and Management N2 - The invasive oak lace bug Corythucha arcuata (Say, 1832) (Hemiptera: Tingidae) was first recorded in lowland stands of pedunculate oak (Quercus robur L.) in Eastern Croatia in 2013, from where it expanded to the west causing summer yellowing and intensive chlorotic damages of oak leaves. In 2018, the entomopathogenic fungus Beauveria pseudobassiana Rehner and Humber (Hypocreales: Cordycipitaceae) was isolated from several dead C. arcuata adults found in moss, a typical place for overwintering. The first aim of this study was to estimate the number of overwintering adults per m2 of moss, their natural mortality, and natural infestation by this fungus. Moss and oak lace bugs were collected from oak trees at six different locations in infested forests in Spačva basin. C. arcuata individuals were counted and separated for further analysis and determination of possible fungal infections. Results demonstrated a high rate of mortality among overwintering individuals (65%), with 19% of them infested by various entomopathogenic fungi, of which 70% belonged to B. pseudobassiana. The second aim of this study was to test fungal virulence against C. arcuata under laboratory conditions and to study differences between the isolates. A suspension of conidia (concentration: 1 × 108 conidia/ml) was sprayed on healthy adults of C. arcuata on moss patches. Results showed no difference in mortality rates between the isolates (96–97%), but one isolate produced a mycosis of 49% compared to 32% of the other isolate, with 4% of mycosis in control. The results presented here demonstrate this fungus as an antagonist, and indicate it as a potential candidate for future biological control of this invasive pest. Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:eb1-opus-4973 SN - 0378-1127 SN - 1872-7042 IS - 491 PB - Elsevier ER -