Comparative study on identification and pathogenicity of fungal pathogens associated with post-harvest rot of tomatoes (solanum lycopersicum l.) in Umuahia and Okigwe

Abstract

Tomato fruits sold in the market and at home present symptoms during storage, but the disease causal agents must be better documented. This study aimed to identify the fungal pathogens associated with tomato rot bought in markets at Umuahia and Okigwe and to evaluate its pathogenicity and disease prevalence. A total of 24 and 16 fungal isolates were recorded, respectively, and were microscopically identified and morphologically to specific fungal isolates. The identified isolates were Alternaria solani, Althelia rolfsii, Colletotrichium phlomoides, Phytophthora nicotinae, Sclerotinia sclerotiorum, and Sclerotium rolfsii. The percentage frequency of isolation of samples from Umuahia ranged from 6.3% - 31%, respectively. Alternaria solani had the highest frequency of 31%, with the lowest percentage of 6.3% recorded in Sclerotium rolfsii from samples obtained from Umuahia. The same trend was also recorded on isolated samples from okigwe with a percentage frequency of isolation of 29% for Alternaria solani and 8.3% for Sclerotium rolfsii. The high percentage frequency of isolation of Alternaria solani indicates a high chance of these tomato fruits being contaminated with mycotoxins since Alternaria solani is a significant mycotoxigenic fungal genus with notable toxicity. The prevalence of disease incidence (PDI) was conducted to ascertain which locations had the highest rate of fungal rot, and there was a higher PDI of 50% in Umuahia against 33% recorded in Okigwe. The highest disease prevalence recorded in Umuahia could result from poor sanitation, poor storage, overcrowding, and unhygienic practices by fruit handlers in this location.