Microalgal bioinoculants for sustainable agriculture and their interactions with soil biotic and abiotic components: A review

Modern agricultural practices have posed a detrimental impact on the environment due to their intensive use to meet the food demands of an ever-increasing population. In this context, microalgal bioinoculants, specifically cyanobacteria and green microalgae, have emerged as sustainable options for agricultural practices to improve soil organic carbon, nutrient availability, microbial quality, and plant productivity. An overview of current and future perspectives on the use of microalgal bioinoculants in agriculture practices is presented in this review, along with a discussion of their interactions with soil biotic and abiotic factors that affect soil fertility, plant health, and crop productivity. The benefits of microalgal bioinoculants include releasing agronomically important metabolites (exopolymers and phytohormones) as well as solubilizing soil nutrients. Furthermore, they function as biocontrol agents against soil-borne pathogens and facilitate the establishment of rhizosphere communities of agricultural importance. So far, very few studies have explored the basic mechanisms by which microalgal bioinoculants interact with soil biotic and abiotic factors. In recent years, advanced molecular techniques have contributed to a better understanding of these interactions.