Comparison of Antagonistic Activity of Pseudmonas fluorescens and Trichoderma viride against Selected Species of Fungal Pathogens

Abstract

Aims: The antagonistic activities of Pseudomonas fluorescens and Trichoderma viride have been evaluated by a number of studies. This research work was aimed to compare the antagonistic activities of Pseudomonas fluorescens and Trichoderma viride against selected species of plant fungal pathogens viz, Pythium aphanidermatum, Fusarium oxysporum, Alternaria alternata and Aspergillus niger. Study Design: In vitro assay of antifungal activity. Methodology: Dual culture method is conducted to compare the antagonistic activities of the bio control agents like Pseudomonas fluorescens and Trichoderma viride against selected species of fungal pathogens viz, Pythuim aphanidermatum, Fusarium oxysporum, Aspergillus niger and Alternaria alternata. Three replicates were maintained for each treatment and mean percent inhibition of radial growth of pathogen in dual culture plate was recorded. Statistical analysis was done to know the significance of comparison. Results: Out of the four fungal pathogens Fusarium oxysporum showed the highest inhibition of radial mycelial growth in the presence of both Pseudomonas fluorescens (49.41±0.4%) and Trichoderma viride (85.7±0.3%). Aspergillus niger recorded the least value. It was found that Trichoderma viride exhibited comparatively greater antagonistic activity compared to Pseudomonas fluorescens. Conclusion: In vitro studies suggested that both the bio controls were effective against four fungal pathogens under the study and are promising biological control for Fusarium oxysporum.