Molecular characters of Pseudomonas cichorii using 16S rDNA isolated from spinach, Limpopo Province, South Africa 

Abstract

Pseudomonas is a genus of Gram-negative, Gammaproteobacteria, belonging to the family Pseudomonadaceae. Pseudomonas cichorii is a Gram-negative soil bacterium that is pathogenic to plants. It has a wide host range and can have an important economic impact on lettuce, celery, and chrysanthemum crops. Pseudomonas cichorii can be a risky pathogenic bactererium in vegetables, including spinach, and therefore have an effect on the fresh production of spinach. This study was conducted to isolate and identify P. cichorii from a spinach field in Limpopo Province, South Africa. The molecular study was conducted in 2023 at Limpopo University to identify the bacterium from South Africa's soils using 16S rDNA marker. The DNA was extracted using the Chelex method. The bacterium was identified as P. cichorii. The Nblast analysis showed South African P. cichorii had 99% similarity with a population from South Africa (FJ477103). Phylogenetic analysis using maximum likelihood placed this species with those molecularly identified as P. cichorii in the same clade with highly supported (100) bootstrap values. The species was identified using 16S rDNA however, the use of other DNA markers can be evaluated for a better understanding of P. cichorii phylogeny.