Ecotoxicological parameters of safe application and adaptation of chemical protection systems against harmful organisms in apple orchards to the soil and climatic conditions of the Precarpathian province of Carpathian mountain zone of Ukraine

Abstract

Goal. Ecotoxicological and economic substantiation of chemical systems of apple protection against harmful organisms, their optimization and adaptation to weather and phytosanitary conditions of apple agrocenosis in the Precarpathian province of the Carpathian mountain zone of Ukraine. Methods. Phytosanitary monitoring was performed visually and using pheromone traps. Classification of pesticides by polarity, determination of residues, study of pesticide detoxification processes in the apple agrocenosis were performed using physico-chemical methods of analysis according to officially approved methods. The degree of hazard of pesticides was assessed by an integrated 7-point scale, the risk — by agroecotoxicological index (AETI). Results. The ecotoxicological characteristics of pesticides of modern assortment used to protect apple trees from pests and diseases were determined: the value of the dipole moment (µ), the detoxication rate constant (parts per day), the period of semi- and complete decomposition (T50 and T95, days) in the apple agrocenosis, the classification according to the degree of hazard of their use was carried out. The most dangerous are non-polar compounds of 1—3 degrees of hazard and partially low-polar of 4 degree, which belong to the I and II class of danger in terms of toxicity (LD50 ) or persistence (k). According to the monitoring of phytosanitary conditions and pesticides in the apple agrocenosis in 2015—2020, scientific and methodological parameters of ecologically safe (AETI <1) and cost-effective systems of chemical protection of apple adapted to soil and climatic conditions of the Precarpathian province of the Carpathian mountain zone of Ukraine were developed: chemical, advanced chemical. Conclusions. Based on the co-measurement of pesticide load with the ability of agrocenosis to self-cleaning, a model of ecologically safe protection of apple orchard from a complex of pests which is adapted to soil and climatic conditions and phytosanitary conditions of Precarpathian province of Carpathian mountain zone of Ukraine was developed. According to research, the rate of detoxification of pesticides in the leaves and fruits of apple depends on their physicochemical properties and correlates with the polarity of the compounds. The classification of pesticides used to control the complex of pests and diseases in the apple agrocenosis was shown. It was shown that modern assortment of pesticides allows to develop protection systems with weighted average degree of hazard at the level Q=5. A model of the maximum pesticide load on the apple agrocenosis, in which the AETI does not exceed 1, has been developed. Investigations and calculations showed that the chemical protection of apple is ecologically and economically viable. In the conditions of 2018—2020, the profit was at the level from forty thousands to ten thousands UAH/ha, with a profitability of 32.4—76.5%.