Management of Sunflower Powdery Mildew and Alternariaster Leaf Spot: Harnessing the Potential of Combined New Fungicide Molecules
C. P. Manjula
All India Coordinated Research Project on Sunflower and Directorate of Research, UAS, GKVK, Bangalore -560065, India.
C. R Jahir Basha
Department of Plant Pathology, CoA, UAS, GKVK, Bangalore, Karnataka- 560065, India.
S. D. Nehru
All India Coordinated Research Project on Sunflower and Directorate of Research, UAS, GKVK, Bangalore -560065, India.
K. M. Srinivas Reddy
All India Coordinated Research Project on Sunflower and Directorate of Research, UAS, GKVK, Bangalore -560065, India.
K. S. Somshekhar
All India Coordinated Research Project on Sunflower and Directorate of Research, UAS, GKVK, Bangalore -560065, India.
M. S. Uma
All India Coordinated Research Project on Sunflower and Directorate of Research, UAS, GKVK, Bangalore -560065, India.
Divyashree *
All India Coordinated Research Project on Sunflower and Directorate of Research, UAS, GKVK, Bangalore -560065, India and Department of Plant Pathology, CoA, UAS, GKVK, Bangalore, Karnataka- 560065, India.
J. Harish
All India Coordinated Research Project on Sunflower and Directorate of Research, UAS, GKVK, Bangalore -560065, India.
Lakshmeesha R
Department of Biotechnology, University of Agricultural Sciences, GKVK, Bangalore, Karnataka-560065, India.
*Author to whom correspondence should be addressed.
Abstract
The study investigates the efficacy of seed treatment with Fluxapyroxad FS @ 1.5 g/kg seed followed by foliar sprays of various fungicide combinations in managing powdery mildew and Alternariaster leaf spot diseases in sunflower. Conducted over three Kharif seasons (2021-2023), the trials consistently demonstrated the superior performance of Fluopyram 17.7% + Tebuconazole 17.7% (400 SC) @ 1 ml/L in reducing disease incidence and severity. In Kharif 2021, this treatment recorded the lowest incidence of Alternariaster leaf spot (7.36%) and powdery mildew (4.52%), outperforming other treatments. Similar trends were observed in Kharif 2022 and 2023, with Fluopyram + Tebuconazole maintaining the lowest disease severities (7.39% and 2.95% for powdery mildew, respectively). Notably, the study found no significant differences in yield components across treatments, though the highest yields were consistently recorded in the treatment combining Fluxapyroxad seed treatment with Fluopyram + Tebuconazole foliar spray, achieving yields of 2124.67 kg/ha in Kharif 2022 and 2157.33 kg/ha in Kharif 2023. These results indicate that integrated disease management using these fungicide combinations can effectively control both diseases in sunflower, particularly under humid weather conditions, without adversely affecting crop yield.
Keywords: Sunflower, alternariaster leaf spot, powdery mildew, disease severity, fungicides