Fungicide action on apple tree resistance to phytopathogens

Reduced yields due to tree damage by various diseases require the use of pesticides and agrochemicals to protect, prevent, and treat plants. The demand for high-quality food products attracts attention to fungicides of biological origin, restricting the involvement of synthetic fungicides. Fungicides are eff ective in combating fungal diseases, which account for up to 50 % of yield losses in Russia each year. Throughout the production cycle, pathogens cause signifi cant damage to agricultural crops. In this work, we employ the conventional and advanced methods of phytosanitary monitoring to study the eff ect of Horus, Antrakol, and Serenada fungicides on the emergence and spread of the most harmful fruit crop fungal diseases – fruit rot, apple scab, and powdery mildew – causing signifi cant yield losses. The research was carried out using the facilities of the Federal Scientifi c Center of Agroecology RAS (Volgograd Oblast, Dubovsky District). The development and spread of diseases were assessed by a standard visual method, consisting in counting the number of damaged fruit trees before and after treatment. The conducted fi eld studies showed high effi ciency of the Antrakol and Serenada preparations in controlling apple scab and other diseases (fruit rot, anthracnose, leaf curl, powdery mildew, etc.). The study was conducted on the ‘Gol’den Delishes’, ‘Gloster’, ‘Margo’, and ‘Vajnspur’ apple varieties. The results showed high resistance of most varieties to diseases. On average, the disease damage of experimental plants did not exceed %, which allowed these varieties to be classifi ed as highly resistant. The ‘Gloster’ variety fruits showed the highest susceptibility to fruit rot, irrespective of the treatments applied, with the level of damage ranging from 3 to 7 %. In order achieve optimal results, all factors aff ecting the eff ectiveness of treatment should be taken into account