Natural entomophages of coccids and their role in agrocenoses of subtropical crops of the Lazarevsky district of Sochi
Abstract
The research aimed to study the biodiversity of native, invasive, and introduced entomophages (predators or parasites) of coccid insects, to select promising species for inclusion in the state bioresource collection of the Federal Scientific Centre for Biological Plant Protection, to develop new and improve existing plant protection systems, and to methods for reproduction and use of entomoacarifugous insects. The work was carried out in 2024-2025 in the humid subtropics of the Black Sea coast of Krasnodar Krai. The study examined the relationships between the development of the main phytophages and their entomophages, as well as the characteristics of their phenology depending on the climatic conditions of a particular growing season. The main entomophage of the euonymus scale ( Unaspis euonymi ) in the study region is the kidney-spot ladybug ( Chilocorus renipustulatus ). The average ratio of the phytophage population to the number of entomophage imagoes, larvae, and pupae was 12.8; 11.5; 10.3, respectively. A new aggressive population of the invasive phytophage, Icerya purchasi, was identified. This species displaces the population of Pulvinaria floccifera , the average density of which over the season was 22.41 individuals per 1 m 2 . The main entomophage of Pulvinaria floccifera in the study region is ladybugs of the subfamily Scymninae . The ratio of entomophage to phytophage at different developmental stages averaged 1:18.4. A new entomophage, a specialised predator of the coccinellid Icerya, Rhodolia Novius cardinalis , was identified for the first time in the surveyed region. Feeding on Icerya larvae by the predatory mite Trombidioidea was also observed. The average ratio of Rhodolia to Icerya during the observation period was 21:9; the average ratio of predatory mites to Iceria was 1:11.35. These data are essential for optimizing environmentally friendly agriculture in the resort area of the Black Sea coast of Sochi.