In vitro evaluation of plant extracts and bio-agents against Alternaria tenuissima (Fr.) keissl causing leaf blight of kodo millet

Abstract

Kodo millet (Paspalum scrobiculatum L.) is nutritionally important millet. Leaf blight has been a major production constraint and fungicidal sprays for the management of any disease on this crop may not be economically viable and feasible as the farmers cultivating the crop are resource poor and the crop is less remunerative, but is important in tribal and rainfed agriculture. Hence, botanicals and bio-agents were evaluated in vitro against Alternaria tenuissima the cause of leaf blight. Ten plant extracts and 14 bioagents were evaluated following dual culture. The results revealed 100 per cent inhibition of the mycelial growth of A. tenuissima by Eucalyptus sp. and Clerodendron infortunatum at 7.5 and 10.0 per cent concentrations. Among the fungal bio control agents tested, maximum inhibition (100 %) was recorded in Trichoderma harzianum (NBAIR), followed by T. viride (81.38 %); whereas the bacterial bio agent Bacillus amyloliquefaciens (P-42) showed only 77.40 % inhibition of mycelial growth revealing that fungal antagonists were more effective than the bacterial antagonists.