Department of Plant Pathology, College of Agriculture, Central Agricultural University, Imphal-795 004, Manipur, India
Online published on 5 December, 2015.
Rhizoctonia solani was isolated from collar regions of infected vegetable seedlings showing typical symptom of both pre-and post-emergence damping-off. In vitro effectiveness of 10 fungicides, four biocontrol agents and 10 locally available plant extracts in controlling the growth and sclerotia formation of R. solani was tested. All the fungicides efficiently inhibited the linear growth of the fungus. Complete inhibition of the fungus was observed with carbendazim, difenconazole, propiconazole, hexaconazole, tricyclazole and ridomil MZ each @ 0.1% and mancozeb and Sixer at 0.2% concentration. Sclerotial formation was completely inhibited by all the fungicides evaluated. In dual culture technique of the fungus and biocontrol agents, of the four biocontrol agents evaluated the antagonists, Trichoderma hamatum and T. harzianum completely over grew the pathogen. Whereas T. viride remained locked with the fungus at the point of contact and Penicillium glabrum formed inhibition zone with the fungus. Sclerotial formation was completely inhibited by all the four antagonists. Garlic extract showed maximum fungitoxic property followed by extracts of neem, ginger, onion, phlogacanthus, goat weed and wild sage. In pot culture experiment, either seed treatment or soil treatment alone or combination of both protected the seedlings from pre-and post-emergence damping-off in the nursery and improved the germination and seedling vigour of cabbage. It was observed that fungicides provided greater efficiency in suppressing damping-off induced by Rhizoctonia solani.
Seedlings, damping-off, Rhizoctonia solani, fungicides, biocontrol agents, plant extracts, seed treatment, soil treatment
