Abstract

Microbial contamination is a constant problem, which often compromise development of all in vitro techniques. This study aimed at investigating the source of microbial contamination in tissue culture laboratories in southwestern Nigeria. Nineteen microbial contaminants (consisting of eleven bacteria and eight fungi) were found associated with the tissue culture plants and the laboratory environments. The bacterial contaminants includes, Pseudomonas flourescens,Escherichia coli, Proteus sp, Micrococcus spp, Streptococcus pneumoniae, Staphylococcus aureus, Bacillus cereus, Bacillus subtilis, Corynebacterium sp and Erwinia sp. While Fungi isolates were Alterneria tenius, Aspergillus niger, Aspergillus fumigatus, Cladosporium sp,Saccharomyces sp, Fusarium oxysporum, Rizopus nigricans and Fusarium culmorum. The rate of occurrence of S. aureus, B. cereus, B. subtilis and E. coli  were found to be higher (ranging from 36-46%) in human skin than in all other sampled materials. The laboratory walls and tables also harbored most of the contaminating microbes. The laboratory indoor air was found associated with all the contaminating microbes.

Key words: Micro-propagation, plant tissue culture, bacterial and fungal isolates, contamination.