Exploring the role of microbial interactions in soil and rhizosphere and their effects on litter decomposition, mycorrhizal associations, and plant growth

Millions of microorganisms inhabit the soil, and some of them contribute to the growth of plants. To gain a better understanding of how microbes promote plant growth, we compared the impact of fungal and bacterial communities on litter decomposition and plant growth. Our study revealed that fungi are the primary decomposers of plant litter and have a more significant impact on nutrient cycling than bacteria. Furthermore, when the fungal and bacterial communities are working together, they have a complementary effect on plant growth that is greater than when either community is working alone. Arbuscular mycorrhizal fungi (AMF) are recognized as one of the most important types of plant symbiotic fungi. AMF are widely distributed in the soil and colonize plant roots. They can functionally extend the plant root system and reach areas in the soil beyond the plant roots, enabling plants to access more water and nutrients. We investigated the microbial community that surrounds the AMF hyphae and discovered that fungal hyphae are colonized by specific bacteria and protists. We demonstrate that the microbes that colonize the fungal hyphae play a crucial role in facilitating mycorrhizal development and assisting plant nutrient uptake. We showed that a particular bacterium of the genus Devosia is associated with AMF hyphae, interacts synergistically with the mycorrhiza and promotes plant growth by facilitating nitrogen uptake. This thesis deepens our understanding of the interactions between different microbial groups and their roles in litter decomposition and mycorrhization processes. A better understanding of plant-microbe interactions is essential for the development of effective application strategies for plant-growth-promoting microbes in agriculture. Ultimately microbes can help create sustainable agricultural practices that rely less on chemical inputs for food production.