Identification of compatible bacterial and fungal isolate and their effectiveness against plant disease

Forty-three isolates of Trichoderma spp. and forty isolates of bacterial (fluorescent pseudomonads) biocontrol agents were isolated and evaluated for their relative biocontrol potential and thereafter development of mixed formulation of efficient compatible fungal and bacterial bio-agents. Different isolates of either Trichoderma or Pseudomonas exhibited differential antagonistic activity with different species of tested pathogens. Pseudomonas in general, suppressed the growth of Trichoderma under in-vitro conditions however, a few combinations were found compatible. Fungal isolate PBAT-43 (T. harzianum) and bacterial isolate PBAP-27 (P. fluorescens) emerged as most compatible and efficient and therefore were used for development of mixed formulation. Individual and mixed formulations were evaluated for their relative bio-efficacy under glass-house and field conditions. Mixed formulation exhibited increase in seed germination ranges from 25.5 - 72.11% and disease control 47.68- 76.00% in different crops as compared to control. Application of compatible mixture of fungal and bacterial biocontrol agents possessing various mechanism of pathogen suppression is suggested as a reliable and potential means of disease suppression.