Biocontrol of Cocoyam (Colocasia esculenta) Spoilage Fungi by Trichoderma harzianum collected from Rivers and Abia State, Nigeria

Abstract

Biocontrol is a technique of controlling pests, whether pest animals such as insects and mites, weeds, or pathogens affecting animals or plants by using other organisms. Hence, the objective of this paper as to investigate the biocontrol of Cocoyam (Colocasia esculenta) spoilage fungi by Trichoderma harzianum collected from Rivers and Abia States in Nigeria using standard microbiological methods. The results obtained show that the fungi isolated were Aspergillus flavus, Aspergillus niger, Mucor sp and Penicillium and Trichorderma sp. Antagonistic fungi was identified molecularly as Trichoderma harzianum strain A0H287. The inhibitory effect of the biological antagonist T. harzianum showed that it reduced the growth of A. niger by 50%, Mucor sp by 34.1%, Penicillium sp by 70% and A. flavus by 63.7%. The study showed that the biological antagonist, Trichoderma showed effectiveness in the reduction of the growth of majority of the pathogenic fungi and could be recommended as alternative to chemical fungicides.