Efficiency of the application of biological systems of the protection of apple trees against powdy dew and scamb in the conditions of the Western Forest-Steppe of Ukraine

Abstract

Goal. To study the effectiveness of different biological systems of apple tree protection against scab and powdery mildew in the Western Forest-Steppe of Ukraine.
 Methods. Phytosanitary monitoring was carried out visually and with the help of pheromone traps. Accounting of the spread and development of diseases was carried out according to generally accepted methods in the phases of apple tree development: «bud swelling», «green cone», «bud extension», «bud separation», «pink bud», «flowering», «end of flowering», «fruit formation», «fruit growth» and «fruit ripening». The technical effectiveness of fungicides was determined after 7 days. Statistical processing of the research results was carried out according to generally accepted methods.
 Results. The results of monitoring the phytosanitary state of apple plantations established that the most common diseases in 2021—2022 in the conditions of the Western Forest Steppe of Ukraine were scab, which affected 15—29% of leaves and 8—13% of apple fruits, powdery mildew, which affected 15—18% of leaves of apple trees, moniliosis, the prevalence of which was 9—13%, and fruit rot, which affected 13—14% of apple fruits. The research results showed that the use of the biological protection system No. 1 (Fluorescin BT, Bactophyt BT, BioHybervit BT, Trihopsin BT, Fluorescin BT) made it possible to reduce the development of powdery mildew by 59.0%, and to reduce the development of scab on leaves and by 59.1%, 62.2% — scab on apple fruits. The use of biological protection system No. 2 (Bactophyt BT + Trihopsin BT, BioHybervit BT, Fluorescin BT, Trihopsin BT, Fluorescin BT) made it possible to reduce the development of powdery mildew by 43.6%, by 47.7% to reduce the development of leaf scab and by 48.6% — scab on apple fruits. The use of biological protection system No. 3 (Ampelomycin BT + Bactophyt BT, Phytosporin + Fluorescin BT, BioGibervit BT, Biospectr BT, Trihopsin BT + Fluorescin BT) made it possible to reduce the development of powdery mildew by 53.8%, and to reduce the development of scab by 68.2% leaves and 67.6% — scab on apple fruits. Using the studied biological systems to protect apple trees from scab and powdery mildew in the conditions of the Western Forest-Steppe of Ukraine yield indicators of 13.2—13.8 t/ha were obtained. The use of the studied biological protection systems made it possible to obtain from 2946 to 8526 UAH/ha of conditional net income and profitability indicators from 72.7 to 229.4%.
 Conclusions. The results of the research established that all investigated systems of biological protection of apple trees against scab and powdery mildew in the conditions of the Western Forest Steppe of Ukraine made it possible to protect apple plantations at a reliable level and obtain high yields. The technical efficiency of the applied protection systems against powdery mildew was 43.6—59.0%, against scab on apple leaves — 47.7—68.2%, and against scab on apple fruits — 48.6—67.6%. The yield for the application of the investigated biological systems of apple tree protection against scab and powdery mildew was 13.2—13.8 t/ha. Biological protection system No. 1 was the most effective in terms of profitability — 229.4%, and the highest indicator of conditional net income was obtained from the use of biological system No. 3 — UAH 8526/ha.