Study of bacterium associated with Spinacia oleracea and nematode, Pseudomonas fragi using 16S rDNA from Limpopo Province, South Africa

Abstract

Microorganisms known as Plant-associated Pseudomonas can thrive as parasites or saprophytes on plant surfaces and within plant tissues. They are crucial in enhancing plant growth by suppressing pathogenic microorganisms, synthesizing growth-stimulating plant hormones, and boosting plant disease resistance. At the University of Limpopo in South Africa, a molecular study was conducted in 2023 to identify a Pseudomonas bacterium in a spinach field associated with a free-living nematode, Acrobeles complexus, in Limpopo Province. The study utilized the Chelex method to extract DNA and the 16S rDNA marker to identify the bacterium as Pseudomonas fragi. Specific primers were then used to amplify 16S rDNA, which identified the bacterium, and Nblast analysis revealed a 96% similarity to a strain from India. Phylogenetic analysis placed this species with those identified as P. fragi in the same clade with highly supported (100) bootstrap values. This marker (16S rDNA) is recommended to use. But for a better understanding of P. fragi's phylogeny, the other DNA markers are recommended to identify this species.