Development of methods for application of pheromonic materials for monitoring and managing the number of apple phytophages

Abstract

Synthetic sex pheromones have found wide application in plant protection as a mean of early detection of pests that allows observation of the phenology of insects to optimise protective measures. Insect sex pheromones can be applied for different purposes in protecting crops such as monitoring, determining the species composition and combating harmful species (by using sex pheromones for disorientation). The present work studies the species composition, dynamics of the number of basic pests of an apple tree, synchronisation of the seasonal and circadian activity of phytophages of an apple tree in the central zone of the Krasnodar Territory. The results of the field assessment of the male complex disorientation method of apple and eastern moths are presented. It was shown that the species-specificity of sex pheromones in the apple orchard depends on the faunistic diversity of Lepidoptera species with similar pheromone systems that develop at a given point in space and time. It was revealed that the behaviour of this complex changes during the season and over years, depending on the climate and natural dynamics of insect populations. The quantitative ratio and species-specificity of pheromones will probably be different in ecosystems with various species composition and different geographic zones. A novelty of this research is the division of the studied Lepidoptera phytophage species into three groups according to a decrease in the absolute species-specificity in the forest biotope in comparison with the garden one. The most widespread and coinciding in terms of summer synchronicity are apple (Cydia pomonella L.), plum (Grapholitha funebrana Tr.), eastern (Grapholitha molesta Tr.) and pomegranate moth (Euzophera bigella Zell.). The disorientation method, applied using a complex system of dispensers with apple and eastern moth pheromones, showed that installing 500 dispensers/ha allowed 99.3 % efficiency to be achieved. Fruit damage amounted to 1.2 % and 2.7 % in the experimental and control groups, respectively. The duration of the disorienting effect of the pheromone formulations lasted for over 4 months.