STUDY OF BIOLOGICAL CHARACTERISTICS OF THE SAN JOSE SCALE (QUADRASPIDIOTUS PERNICIOSUS COMST.) UNDER THE CONDITIONS OF THE RIGHT-BANK FOREST-STEPPE REGION OF UKRAINE

Abstract

The article addresses the issues of the harm and spread of San Jose scale (Quadraspidiotus perniciosus Comst.) in fruit orchards of Ukraine. It has been established that the close relationship of Q. perniciosus with plants, its small size, concealed lifestyle, polyphagy, high fecundity, and ecological plasticity allow this pest to spread widely. Despite annual protective measures, the range of the San Jose scale continues to expand in Ukraine. This is due to the absence of fruit varieties resistant to the pest, as well as the lack of highly effective chemical agents for use in both collective and household gardens. The article analyzes ways to improve measures to limit the pest's population by refining the biological features of Q. perniciosus development, taking into account climatic changes in Ukraine, to determine more accurate timings for protective measures aimed at regulating its population. Monitoring the emergence and dispersal of Q. perniciosus larvae is one of the most necessary elements in the system of measures because chemical treatments are scheduled based on the emergence of San Jose scale crawler larvae. It was also found that some of the overwintering larvae stay in a dormant state throughout the growing season, rather than becoming active in spring. Using chlorovinyl tape coated with "Pestifix" glue, researchers tracked the emergence of the first and second generations of larvae. They analyzed the timing, the pace of larval emergence, and the stages of the pest’s development, depending on population density. By calculating the required sum of effective temperatures for larval emergence, they were able to determine more accurate dates for protective treatments.