Effectiveness of the use of preparations against powdery mildew (Erysiphe necator)

Abstract

Objective. To improve the protection system of table grape varieties against powdery mildew (Erysiphe necator) under the conditions of the Southern Steppe of Ukraine by evaluating the effectiveness of fungicides from different chemical groups under epiphytotic disease development.
Methods. The research was conducted during 2023-2025 in commercial vineyards in Odesa region at Green Technology LTD. The object of the study was the indicator seedless variety Sublima Seedless. Field small-plot trials, phytopathological monitoring, calculation of technical efficacy using Abbott’s formula, and statistical data analysis were applied. Preparations from the triazole, strobilurin, quinazolinone, and morpholine groups were studied.
Results. Analysis of meteorological conditions confirmed a regional climate change trend that contributed to the aggressive development of powdery mildew. In the critical year 2025, 100% cluster infection on the rachis was recorded in the control, resulting in 89,1% yield loss. It was established that conventional protection with such products as Falcon and Flint Star provided only a moderate level of control, indicating the development of resistance in the local pathogen population. The highest efficacy was demonstrated by Linder and Talendo. Their application ensured technical efficacy at the level of 72-80%, with yield per vine of 15,8-16,5 kg and an average cluster weight of 750-780 g, corresponding to the ampelographic standards of the variety.
Conclusions. The advantage of fungicides with lipophilic properties and vapor-phase activity, namely active ingredients from the morpholine and quinazolinone groups, was demonstrated under arid climate conditions. The inclusion of products based on fenpropidine and proquinazid in the protection system is recommended to reduce resistance of the grape powdery mildew pathogen.