Evaluation of Plant Activators and Preparations for Control of Red Leaf Blotch Disease (Polystigma amygdalinum P.F. Cannon) in Almond Cultivation in Turkey
摘要
Red leaf blotch disease (Polystigma amygdalinum P.F. Cannon) is a major problem for almond growers, especially in regions with temperate climates that are conducive to the development of the disease. This study investigated the potential of plant activators and organic preparations as sustainable alternatives to chemical pesticides for managing this disease. A 2-year field experiment was conducted from 2022 to 2023 in a commercial almond orchard in Adıyaman, Turkey, where the activators ISR-2000 (0.5, 1, 2 ml L−1) and Crop-Set (4.5, 9, 18 ml L−1), along with the organic preparation Master Gold (0.62, 1.25, 2.50 ml L−1), were tested. The experiment was designed as a randomized block design, and leaf samples were collected annually to assess infection incidence, severity, and treatment efficacy. The results demonstrated that all tested treatments significantly reduced disease incidence compared to the untreated control method (UTC). The ISR-2000 (1 ml L⁻1) demonstrated the highest efficacy, achieving a control rate of 92.08% in 2022 and 85–90% in 2023, with the lowest disease severity recorded at 3.39%, while Master Gold (2.5 ml L⁻1) exhibited the lowest efficacy at 48.32%, emphasizing the superior potential of plant activators as sustainable and effective alternatives to chemical pesticides for managing red leaf blotch disease in almonds. These findings underscore the effectiveness of organic preparations and plant activators as viable and sustainable alternatives for managing red leaf blotch disease in almond orchards. The data obtained emphasize the potential to achieve up to 90% disease control and support the applicability of these methods.