Cultivar response against root-infecting fungi and efficacy of Pseudomonas aeruginosa in controlling soybean root rot

Abstract

A study was conducted in the greenhouse to examine the resistance of three soybean cultivars against root-infecting fungi, and to determine the role of five strains of Pseudomonas aeruginosa in protecting the roots from these fungal pathogens. In this study soybean cv RAWAL was found to be less susceptible against charcoal rot fungus Macrophomina phaseolina than cvs PARC and BRAGG. Most of the strains of P. aeruginosa used as seed dressing significantly reduced M. phaseolina and Rhizoctonia solani infection on all three cvs PARC, BRAGG and RAWAL (p < 0.05). Most of the strains of P. aeruginosa were effective on cv PARC against Fusarium solani infection, while on cv BRAGG P. aeruginosa strain Pa₃, and on cv RAWAL strain Pa₅ were effective. Both strains Pa₃ and Pa₂₂ gave maximum plant height and fresh weight of shoots, respectively on cvs PARC and BRAGG than other strains. These characteristics make these P. aeruginosa strains good candidates for use as biocontrol agents against soil-borne plant pathogens.

Key words:

• Soybean cultivars
• root rot
• Pseudomonas aeruginosa
• biocontrol

Acknowledgements

This research was supported by a research grant from Pakistan Atomic Energy Commission, Islamabad.