Use of Aazadirachta indica aqueous leaf extracts for the control of mycotic deterioration of yam tubers (D. rotundata poir)

Abstract

Considering the recurrent yam tuber rot in the tropical region of the world, all hands in crop protection need to be on deck to contain the menace, as it portends great danger to food security. Hence, cheap, accessible, easy to formulate and eco-friendly control measures need to be fully explored. B. theobromae, A. niger, A. flavus , A. glaucus were isolated from the rotten tissues and identified. The radial growth of B. theobromae was most reduced by 92.57% at 50g/100ml of hot water extract of A. indica. Similarly, hot and cold water extract of A. indica at 50g/100ml was most effective on A. flavus by 94.98% and 97.30% respectively. A. glaucus (100%) and A. niger (90.17%) were respectively inhibited at 50g/100ml of cold water extract of A. indica. The antimicrobial effects of hot and cold water extract of A. indica on the fungal rot organisms differed significantly from the control and standard. The efficacies of both cold and hot water extracts of A. indica on the rot organisms increased with increase in concentration.