Isolation and identification of fungi associated with leaf tip blight diseases of kolanut (Cola SP. L.)

Abstract

Kola nut is an important cash crop in West Africa with great economic importance and also used in several cultural and traditional ceremonies. The leaf tip blight disease is characterized by the appearance of necrotic lesions on the tip of leaves which progresses with time, the colouration of the affected area changes from pale yellow to brown death patches over time. This study involved collection of the kolanut leaves, isolation and identification of the fungal pathogens associated with the blight. The pathogens were isolated by agar plate method using Potato Dextrose Agar. The inoculated plates were covered and left at room temperature for seven days and was observed daily. Their macroscopic features were observed by monitoring the plates and microscopic features using light microscope. The fungal pathogens isolated and identified were Aspergillus fischeri, Aspergillus flavus, Aspergillus niger, Gloeosporium sp. and Rhizoctonia sp. The percentage abundance of the fungal isolates were 23%, 43%, 16%, 16% and 2% respectively. These lesions lead to decreased photosynthetic activity of the leaves thus affecting the yield of the kolanut produced. The result of this study shows valuable information on the fungal causing leaf tip blight in kolanut and can be instrumental in developing control measures and management strategies for the disease.