Studies on Banded Leaf and Sheath Blight of Maize Caused by Rhizoctonia Solani f. sp. Sasakil Exner
Loading...
Date
2013
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
UAS, Dharwad
Abstract
Banded leaf and sheath blight of maize caused by Rhizoctonia solani f.sp. sasakii
Exner is an important disease which results in heavy yield loss. The investigations include
main aspects viz., survey, variability of pathogen, in vitro evaluation of fungicides, bioagents,
botanicals and management of the disease. The results of the investigations are summarized
hereunder
The roving survey on the disease severity revealed that, maximum disease severity
was observed in Kalaghtagi (52.45%) followed by Mundgod (51.54%). Minimum severity
was noticed in Bailhongal (15.72%). Highest disease severity observed in black soil under
irrigated area on DKC 8101 hybrid in Kalaghtagi taluka of Dharwad district. Six isolates
collected from different part of Northern Karnataka were studied for their variability. The
isolates showed variability in morphological and cultural characters. Among six isolates,
isolate Rsm6 (Kalaghatagi) was found to be fast growing, maximum sclerotial size (3.1mm),
oval shape and red brown sclerotia, minimum time took for initiation of sclerotial production
(8 days) and highest number of sclerotia per plate (115).
The in vitro studies on fungicides evaluation at various concentration, indicated
Propiconazole 25% EC and Carbendazim 50% WP were found most effective in inhibiting
the growth of the fungus. The plant extracts viz., nimbicidine and NSKE at 5 and 10 per cent
concentrations were effective against the pathogen. Among the biocontrol agents evaluated,
Trichoderma harzianum found effective against the pathogen. Field studies on the
management of the disease revealed that, seed treatment with Pseudomonas fluorescens @10
g kg-1 seed followed by two sprays of Propiconazole 25 EC @ 0.1% at 30 and 40 DAS found
most effective treatment and resulted in lowest PDI (20.40%). This treatment increased grain
yield (40.72%) and fodder yield (44.68%) over untreated check.