Integrated Management of Sclerotium Wilt /Stem Rot of Potato Caused by Sclerotium Rolfsii. Sacc.
- M.Sc. (Agri)
- Dharwad University of Agricultural Sciences 2024
- 120 32 Cms
ABSTRACT
Potato (Solanum tuberosum) is a vital vegetable and global food crop, threatened by many diseases, stem rot caused by Sclerotium rolfsii Sacc. is one among them causing significant yield losses. Present study aimed to assess the disease incidence across different locations, in vitro evaluation of fungicides and bioagents against S. rolfsii to develop integrated disease management strategies and to identify resistant source through screening. A roving survey in three districts of Karnataka revealed the highest disease incidence of 28.26 & at MARS, Dharwad and the lowest at Kanchenahalli village of Hassan district (5.31%). Among the systemic fungicides tested penflufen 240 FS, propiconazole 25% EC and hexaconazole 5% EC exhibited complete inhibition of mycelial growth at all the concentrations tested (0.025%, 0.05%, 0.1%). Among the five combi-product fungicides tested (carbendazim 12% + mancozeb 63%) 75% WP, (carboxin 37.5% + thiram 37.5%) 75% WP and (penflufen 13.28% + trifloxystrobin 13.28%) 26.56% SC achieved cent per cent mycelial growth inhibition at all the concentrations. Among the bioagents evaluated Trichoderma harzianum was the most effective bioagent inhibiting 65.82 per cent of mycelial growth of S. rolfsii under in vitro conditions. Field experiments during kharif 2023 demonstrated that tuber treatment with penflufen 240 FS (1ml/10 kg tubers) and soil application of vermicompost enriched with Trichoderma harzianum (250 kg + 2.5 kg)/acre along with biofumigation with mustard resulted in the lowest stem rot incidence (16.80%) and highest tuber yield (125.14 q/ha) with a B:C ratio of 2.65. Out of 58 potato genotypes screened under natural epiphytotic conditions, none were immune or highly susceptible to stem rot. However, genotypes such as AICRP-P-57, AICRP-P-24, AICRP-P-86 and AICRP-C-20 exhibited resistance reaction against Sclerotium rolfsii.