Vol. 11, Special Issue 2 (2022)

Author(s):
Anamika Manhas, Richa Sharma and Stanzin Dorjey

Abstract:
Present studies on stem rot of chickpea caused by Sclerotinia sclerotiorum were carried out with an aim to determine the prevalence of Sclerotinia stem rot, development of symptoms, role of weather factors on disease development and morphological and cultural characters of the pathogen. Morphological and cultural studies revealed that fungus produced fluffy, white colour, gelatinous mycelium on potato dextrose agar media. Sclerotia were formed on potao dextrose agar. Epidemiological studies revealed that that the stem rot commenced from 2^nd January (2^nd standard week of 2013) reaching its highest peak 32.55 per cent in C-235 and 27.88 per cent in L-550. The disease development was maximum during 2^nd to 6^th standard week when maximum temperature ranged from 17.80 to 20.50 ⁰C and relative humidity 91.30 to 96.10 per cent. Newer group of fungicide evaluated against sclerotinia stem rot causing pathogen, best results were obtained with tebuconazole which recorded 62.38 per cent inhibition followed by hexaconazole at 100 ppm. In case of traditional group of fungicides best results were obtained with carbendazim which recorded 73.83 per cent inhibition followed by SAAF (carbendazim 12% + mancozeb 63 WP) at recommended concentration. The antagonistic activity of two fungal and two bacterial biocontrol agents namely Trichoderma harzianum, Trichoderma viride, Pseudomonas fluorescence and Bacillus subtillis was studied by dual culture. Trichoderma harzianum yielded better results by inhibiting 63.41 per cent growth of Sclerotinia sclerotiorum. In case of bacterial biocontrol agents Bacillus subtillis yielded better results by inhibiting 57.77 per cent growth of the pathogen.