In vitro analysis of growth media and the control of yam minisett-rot

Abstract

Yam minisetts are susceptible to rot caused by microorganisms in both the sprouting media and mother seed yam. This study was conducted to determine the most effective treatment of yam minisetts against rot organisms. Five different protectants/disinfectants were used in vitro and replicated thrice. The result revealed that disinfectants (sodium hypochlorite and aqueous neem leaf extract), protectants (lime, wood ash and Benlate) either suppressed or inhibited the growth of fungi in vitro. Benlate inhibited the growth of all the test fungi, except Rhizopus stolonifer that was tolerant to the fungicide. Aqueous neem leaf extract was the least effective among the disinfectants in controlling fungal growth in vitro. Both quicklime and wood ash suppressed the growth of Aspergillusflavus and Rhizopus stolonifer and completely inhibited the growth of Sclerotium rolfsii and Penicillium sp. Sodium hypochlorite completely inh_ibited the growth of Sclerotium rolfsii and suppressed the growth of Aspergillus flavus, Fusarium sp.: Rhizopus stolonifer and Trichoderma sp. Higher concentrations of the disinfectants and protectants were more effective in controlling the growth of these fungi than the lower concentrations