Goal. Clarification of certain biological features of development and seasonal dynamics of the flight of peach twig borer in peach orchards of the Southern Steppe of Ukraine.
Methods. Field — research of the biological features of peach twig borer development using pheromone-trap method was conducted in accordance with generally accepted methods in peach orchards of SPS “Naukova” of Melitopol fruit growing research station named after M.F. Sydorenko of IH of NAAS of Ukraine
Results. It was determined that in the conditions of peach orchards in the South of Ukraine restoration of feeding peach twig borer caterpillars began in the end of March — the middle of April, and the hatching — in the end of April — the beginning of May. During 2018—2020, the beginning of the flight of butterflies of the pest was observed starting from 06 to 18 May, with the accumulation of the sum of effective temperatures (SET) >8°С 154.5—254.3 and lasted continuously until September 18—30 (134—141 days) with three peaks. The appearance of the pest caterpillars was observed from the 2—3rd ten-day period of May (SET>8°С 299.0—349.5°С). The peaks of peach twig borer flight were observed in the 3rd ten-day period of May, late June — early July, and during the 3rd ten-day period of July — mid-August. The duration of the development of the first generation was 44—50 days, the next — 30—40 days, with accumulation of SET>8°С from imago to imago varying between 436.5 and 743.0°С.
Conclusions. In the south of Ukraine, three peaks of flight and development of two full generations of peach twig borer are noted, caterpillars of the third generation completed the development in the spring of the following year. Fluctuations in the number of imago during the growing season were influenced by both meteorological factors and the degree of reproduction of the pest of the previous generation. During the years of research, the highest intensity of catching of butterflies of a fruit striped moth was noted in July — August at high mean weakly air temperatures (25.0—26.9°С) and the conditions of severe drought (HTC 0.2).
Studying some biological features of pear cultivars blossoming in the south of Russia