Recent Advances in Bioinoculant Formulations and Their Shelf-Life: A Review.

Soil parameters, such as temperature, moisture, aeration, and nutrient composition, significantly affect plant growth and development. Agricultural methods currently depend on chemical fertilizers and pesticides to increase crop yields. However, excessive use of these fertilizers may lead to environmental pollution, soil deterioration, and the accumulation of heavy metals. Bioinoculants have emerged as promising solutions to address these challenges and promote sustainable agriculture. These beneficial microorganisms, including bacteria, fungi, and algae, can improve soil fertility, stimulate plant development, and increase nutrient uptake. Bioinoculants augment plant defense systems against pests and diseases, increasing agricultural yield while reducing reliance on chemical fertilizers. A key constraint impeding the utilization of bioinoculants is their restricted shelf life. Researchers have investigated several formulation processes and carrier materials to improve the survival rate of these bacteria. The longevity of bioinoculants can be extended by enhancing formulation techniques, selecting suitable carrier materials, and maintaining ideal storage conditions. This review thoroughly examines techniques, including carriers, adjuvants, stickers, and protectants, as well as smart delivery technologies, such as nanobiofertilizers, freeze-drying technology, biofilm formulation, rhizosphere engineered bioinoculants and direct seed injection techniques, to increase shelf life and effectiveness. Furthermore, the review discusses market challenges, international regulations, farmer incentives, and the role of public‒private partnerships in standardizing formulations. The integration of biofertilizers with regenerative agricultural practices and patent-related considerations are also examined. Overall, this review aims to provide a comprehensive understanding of strategies to increase the shelf life and performance of bioinoculants, facilitating their widespread application in sustainable agriculture.