Evaluation of Bioagents for Their Compatibility in the Development of Consortium for Enhanced Efficacy

The concept of development of microbial consortia for bio-control relies on the fact that bioagents under natural habitats live in communities with some benefits for plants. Till now no guideline has been published for the evaluation of bioagents to test their compatibility before developing bioagent consortium. In the present studies compatibility among biocontrol potential TrichodermaPseudomonas and Trichoderma-Trichoderma isolates was studied by dual culture, mixed formulations and using cell free cultures. In dual cultures all the combinations (14 nos.) were found compatible with each other as no isolate inhibited the growth of one-another i.e. absence of inhibition zone. All the mixed formulations of potential Trichoderma-Pseudomonas isolates (8 nos.) were found compatible with each other as they were growing simultaneously on the PDA without antagonizing the growth of other or formation of inhibition zone in their combinations. The cell free cultures of each Trichoderma and Pseudomonas isolates tested with each other using Food Poison Technique showed synergistic effects on their fresh mycelial weight among some combinations while majority showed no significant differences with their checks. Further, all the combinations (14 nos.) were tested for their effects on seed germination and vigour index of chickpea in glasshouse. All the combinations showed significantly better seed germination while some combinations, viz., Th14+Psf173, TCMS36+Psf173, Th17+Th19, Th17+Psf2, Th17+TCMS36 and Th14+Psf2 showed a better plant vigour index (43.5 to 44.9%) as compared to their checks (28.8 to 41.5%). These guidelines could be used before developing bioagent consortium and evaluation in field for crop health management. environmental conditions. Diversity in biocontrol mechanisms offered by each bioagentin consortium may help in enhancing disease suppressiveness and may also strengthen the capabilities of the partners in an additive or synergistic manner. Biocontrol attributes also are more in consortia in comparison to using single isolates (Thakkar and Saraf et al., 2015). Studies on employing indigenous bacterial and fungal antagonistic consortia are very limited. The development of new biocontrol consortium requires various screenings of two or three microbial antagonists to prevent inhibitory action on each other. Antagonists for commercial use have to fulfill many different requirements. In relation to this, the present study had focused on the approach to develop guidelines for the evaluation of antagonistic microbial consortium could help in effective plant disease management. Testing of compatibility of Biocontrol Agents (BCAs) Selected isolates of Trichoderma harzianum Th14, Th17, Th19, and TCMS36 and P. fluorescens Psf-2 and Psf