Management of Black Scurf of Potato Caused by Rhizoctonia solani in Eastern Uttar Pradesh

Black scurf of potato, caused by Rhizoctonia solani (Kuhn), is a significant soil-borne disease that hampers potato cultivation in Eastern Uttar Pradesh by reducing both tuber quality and yield. The pathogen’s persistence in the soil and on the seed tubers necessitate effective disease management strategies, especially under field conditions where environmental factors favour disease development.

Field experiments were conducted during the rabi seasons of 2022–23 and 2023–24 at the Main Experimental Station, Vegetable Science and UAT, Kumarganj, Ayodhya. This study aimed to evaluate the efficacy of various fungicidal seed tubers treatments against black scurf using the variety Kufri Sindhuri. The study followed a randomized block design (RBD) with five treatments including Pencycuron 22.9 SC, Penflufen 22.43% FS, Thifluzamide 24.0 SC, a combination of Mancozeb 50%+ Carbendazim 25% WS and an untreated diseased tuber (control). Disease incidence, severity and tuber yield were recorded and statistically analysed.

All tested fungicidal treatments significantly reduced black scurf incidence and severity compared to the untreated control. Among them, Pencycuron 22.9 SC was the most effective, reducing disease incidence to 5.20% and enhancing yield to 243.00 q/ha in the 2023–24 season. Thifluzamide 24.0 SC also demonstrated high efficacy, particularly in reducing the disease index to 5.36%. Although yield differences were not statistically significant in the second year, the overall trend indicated a positive correlation between disease suppression and yield improvement. These findings support the adoption of fungicidal seed tuber treatment, particularly with Pencycuron and Thifluzamide, as an integral part of black scurf management strategies in Eastern Uttar Pradesh.