In-vitro efficacy of fungicides, bioagents and plant leaf extracts against Sclerotium rolfsii causing collar rot disease of french bean (Phaseolus vulgaris L.)

摘要

The efficacy of five each systemic fungicides viz., Bavistin (Carbendazim), Vitavax (Carboxin+ Thiram), Tilt (Propiconazole), Contaf (Hexaconazole), SAAF (Carbendazim 12% + Mancozeb), non-systemic fungicides Zineb (Indofil Z-78), Blitox-50 (Copper oxychloride), Antracol (Propineb), Indofil M-45(Mancozeb) and Kavach (Chlorothalonil), seven plant leaf extracts Oscimum sanctum, Lantana camara, Azadirachta indica, Pongamia pinnata, Daturastra monium, Parthenium hysterophorus, Annonas quamosal and four Ranchi and Delhi isolates of Trichoderma spp were tested against Sclerotium rolfsii causing collar rot of French bean. The efficacy of fungicides and leaf extracts was evaluated by poisoned food technique against Sclerotiumrolfsii while efficacy of bio-agents was evaluated by mono cultureand dual culture technique. Among the systemic fungicides Propiconazole, Vitavax, Hexaconazole and SAAF each at 0.025%, 0.05% and 0.01% concentration completely inhibited the mycelial growth of S. rolfsii. Among the fivenon-systemic fungicides tested Zineb, Propineb, Mancozeb and Kavach were found to be more effective showing 100% inhibition of mycelial growth at all concentration (0.1, 0.2 and 0.3%). Among the seven botanical tested, Pongamia pinnata at 10% concentration was found most effective and showed maximum inhibition of mycelial growth(58.36%) followed by Azadirachta indica (57.24%) at 10% concentration. Among the isolates of bio-agents maximum colony diameter (90 mm) on PDA medium was observed by Trichodermaharzianum (R -Ranchi isolate) and T. viride (D-Delhi isolate) under the mono culture. In dual culture maximum inhibition of mycelial growth (25.66%) was recorded by T. viride (D) after 48 hrs. while maximum inhibition of mycelial growth (41.69%) was observed in Trichoderma harzianum(D) after 72 hrs.