Effectiveness of nanoaquachelates of transition metals against scab in industrial apple plantations

Goal. To compare the effectiveness of chemical and improved protection schemes and to determine the effectiveness of using different concentrations of a mixture of nano-acquahelates of transition metals Cu, Zn, Fe in the scheme of protection of apple plantations against scab in the south of Vinnytsia region. To evaluate the effect of the mixture of these compounds on the yield and marketability of fruits in apple trees of the Champion variety. Methods. Laboratory — the sensitivity of micromycetes Venturia inaequalis (Cooke) G. Winter, Alternaria alternata (Fr.) Keissl, Monilinia fructigena (Pers.) Honey to the studied mixture of metals. Field — 2 schemes of protection of plantations from apple scab were studied. 1 — chemical, based on the use of pesticides of chemical origin: Nordox 75, WG (copper oxide, 860 g/kg, equivalent to 750 g/kg Cu, Br), Delan, WG (dithianone, 700 g/kg), Flint Star 520 SC, CS (pyrimethanil, 400 g/l + trifloxystrobin, 120 g/l), Malachite CS (dithianone, 250 g/l + pyrimethanil, 250 g/l), Skor 250 ES, CE (difenoconazole, 250 g/l), Topsin-M 500, CS (thiophanate-methyl, 500 g/l). 2 — improved, which included treatments with chemical protection agents (Nordox 75, WG, Horus 75 WG, WG (cyprodinil, 750 g/kg)) with the addition of a mixture of nano-acquahelates Cu, Zn, Fe in w.p. (0.1, 0.2, 0.3 l per 600 l of water/ha) in the phases BBCH 56, 72—74, 75, as well as 2—3 weeks before the ripeness of BBCH 81—87 fruits. The control was water treatment. Results. The effectiveness of using a mixture of compounds in the scheme of protection of industrial apple plantations was evaluated. Laboratory screenings have confirmed that nanoaquahelates of Cu, Zn, Fe in aqueous form have a fungicidal effect and can be used as an alternative to chemical pesticides. A positive trend of the influence of the improved scheme with the introduction of nanoaquahelates on the yield of apple trees was established — an increase of 46.6% in 2022 and 106% in 2023 compared to the control, as well as indicators of marketable quality of fruits by 60—136% compared to the control. Conclusions. The use of an improved scheme of protection of apple trees from scab provided a biological efficiency of 56—73% at a consumption rate of 0.2—0.3 l/ha of aqua chelates on the 5th—7th day after treatment. The effectiveness of the chemical protection scheme based on Nordox 75, WG, Delan, WG, Flint Star 520 SC, KS, Malachite KS, Skor 250 ES, KE, Topsin-M 500, KS, recommended for the control of this pathogen, was 64—95% on the 5th—7th day after application. There was a positive trend of influence of the improved protection scheme in 2022 on the indicators of marketable quality of fruits with sufficient moisture. However, dry conditions in 2023 led to a decrease in yield, a decrease in fruit diameter and a deterioration in their marketability compared to the chemical protection scheme. It was found that the most effective against apple scab was a chemical protection scheme based on traditional contact, systemic and combined chemicals recommended for the control of this pathogen, while the scheme was characterized by higher cost and lower environmental safety.