Innovative formulations enriched with Bacillus velezensis S26 endospores using whey and composting leachate to enhance plant growth and mitigate strawberry diseases

Bacillus velezensis is an endospore-forming bacterium renowned for its ability to enhance plant growth, inhibit various plant pathogens, and induce plant resistance. This study aimed to develop a cost-effective formulation with B. velezensis S26 endospores using agroindustrial wastes and evaluate its efficacy in improving plant growth and managing diseases in strawberry cultivation. Bacterial sporulation was initially induced in shaking flasks using whey and composting leachate, either individually or in combination. Then, the potential of the bioformulations to increase plant growth and suppress anthracnose and gray mold was evaluated in strawberry plants, in a pot experiment and in a commercial greenhouse production. The findings revealed that utilizing whey and composting leachate ensured B. velezensis S26 sporulation both in shaking flask and bioreactor conditions. Additionally, all formulations effectively controlled anthracnose and gray mold, exhibiting a similar efficacy to Serifel^®, while bioformulation BF4 also enhanced plant development. Therefore, the valorization of composting leachate and whey as carriers for B. velezensis S26 formulations contributes to sustainable strawberry production.