Observations of Pseudomonas fragi in connection with tomato (Solanum lycopersicum) using 16S rDNA from Limpopo Province, South Africa

Abstract

Tomato (Solanum lycopersicum L.) is one of the premier vegetables in the world and is widely cultivated. As it is a relatively short-duration crop with a high yield, it is economically attractive, and the area under cultivation is increasing. Many studies showed when plants are associated with Pseudomonas, the growth parameter of plants promote because of suppressing pathogenic micro-organisms, and plants become resistant to disease. This study was conducted to isolate and identify a Pseudomonas bacterium from a tomato field in Limpopo Province, South Africa. Therefore, the molecular study was conducted in 2022 at the University of Limpopo to identify the bacterium associated with tomato filed from South Africa's soils using 16S rDNA marker. The DNA was extracted using the Chelex method. The bacterium was identified as Pseudomonas fragi. The Nblast analysis showed South African P. fragi has 96% similarity with a strain from Italy (MG972899). Phylogenetic analysis using maximum likelihood placed this species with those molecularly identified as P. fragi in the same clade with highly supported (100) bootstrap values. In conclusion, this species was identified using 16S rDNA; however, other DNA markers are recommended for a better understanding of P. fragi phylogeny.