Studies on shelf life of Trichoderma spp. and Pseudomonas fluorescens in different formulating materials

Shelf life of two fungal bioagents i.e. Trichoderma viride and Trichoderma harzianum and one bacterial bioagents i.e. Pseudomonas fluorescens was studied. Total six types of formulations were prepared using sterilized and unsterilized formulating materials viz; talc, vermiculite and lignite. The colony forming unit (cfu) of these formulations was enumerated at 30 days interval up to 120 days in respective formulation. The studies showed that the viability of all tested bioagents was higher when sterilized formulating material was used. A gradual loss in viability of antagonists over the storage period was recorded. The colony forming units of talc based formulations of Trichoderma viride, Trichoderma harzianum and Pseudomonas fluorescens were higher as compared to lignite or vermiculite based formulations. In the best formulations i.e. talc + Carboxy methyl cellulose (cmc), maximum population of both Trichoderma viride, Trichoderma harzianum and Pseudomonas fluorescens was recorded as 15 cfu x10¹⁰ g⁻¹,16 cfu x10¹⁰ g⁻¹ and 15 cfu x10¹⁴ g⁻¹ formulation, respectively.