TITLE:
Molecular Identification of Organisms from Tomato (Solanum lycopersicum) Collected from Choba Market, Rivers State, Nigeria
AUTHORS:
Famous Ovworayini Akiti, Sobomate Chuku, Keayiabarido Jude, Miracle Uzoma, Emmanuel Bakpo, Aroloye Numbere
KEYWORDS:
Bacteria, DNA Sequencing, Fungal Infection, Phylogenetic Tree, Spoilage, Tomatoes
JOURNAL NAME:
American Journal of Plant Sciences,
Vol.17 No.9,
September
29,
2026
ABSTRACT: Tomatoes (Solanum lycopersicum) are highly nutritious but prone to microbial contamination due to their high moisture content. This study investigated fungal species associated with tomatoes sold in three markets in Choba (TO1 - TO3), evaluated potential health risks, and provided molecular data relevant to food safety. Tomato samples from three different markets (n = 3 × 10) were cultured on Potato Dextrose Agar (PDA) and examined using morphological, microscopic, and molecular techniques. Distinct colonies were characterized, and DNA was extracted for amplification of the Internal Transcribed Spacer (ITS) region using Polymerase Chain Reaction (PCR) followed by Sanger sequencing. Phylogenetic analysis was used to determine evolutionary relationships among isolates. Results indicated a high fungal load, with colony counts ranging from 50 to too numerous to count (TNTC). Morphological and microscopic observations revealed predominant fungi as Aspergillus niger, Mucor spp., and yeast-like species. Molecular identification revealed that isolates were closely related to Fusarium verticillioides, Geotrichum candidum, and Puccinia brachypodii, with sequence similarities of 87.7%, 99.6%, and 88.8%, respectively. Phylogenetic tree analysis showed these identifications and highlighted potential spoilage and health risks associated with the isolates. The low percentages derived may be due to small sample size and limited sequencing. This study demonstrates that tomatoes from Port Harcourt markets may harbor diverse fungal species capable of reducing fruit quality and posing health risks to consumers. Next study will consider increasing the sample size, conducting the experiments in a more aseptic condition and conducting more sequencing.