Soil–Plant–Microbe Interactions Determine Soil Biological Fertility by Altering Rhizospheric Nutrient Cycling and Biocrust Formation

Abstract

Understanding soil–plant–microbe inter- and intra- interactions are essential for ensuring proper soil health, quality, and soil-mediated ecosystem services (e.g., nutrient cycling) required for human–plant–animal life. Intensive and unsustainable farming practices can decrease soil microbial biodiversity, fertility, and quality leading to soil degradation, impaired nutrient cycling, and the incapability of soil to support plant growth. Under such a context, soil biological fertility can appear as a regenerative component that has the potential to harmonize and improve soil’s physical, chemical, and biological parameters. This study defines and discusses the microbiome in the rhizosphere, microbial nutrient cycling, and biological soil crusts as the major components of soil biological fertility, and explores the answers to the following questions: (i) how does the rhizosphere promote plant growth, development, and nutrient cycling through soil microorganisms (e.g., bacteria, fungi)? (ii) How can soil microorganisms regulate macronutrient cycling and facilitate biocrust formation? This review reveals that soil biological fertility is crucial for increasing crop resilience and productivity as well as sustainability in agriculture. Additionally, the reintroduction of plant growth promoting rhizobacteria, a quantitative estimation of the root exudate’s composition, identifying the spatiotemporal dynamics of potassium solubilizing bacteria and establishing biological soil crusts in agricultural lands remain the major tasks for improving soil biological fertility and the transition towards regenerative agriculture.

Microbiome analysis revealed distinct microbial communities occupying different sized nodules in field-grown peanut

“…However, the proper functioning of soil microbial communities depends on many factors including the availability of nutrients, temperature, water, soil structure, pH, and host genotypes and their secreted root exudates (Zgadzaj et al, 2016;Li et al, 2017;Pramanik et al, 2020;Vaidya and Stinchcombe, 2020). An understanding of endophytic or epiphytic soilmicrobe interactions with host roots is of great importance because of their potential to promote plant growth in various ways through enhanced nutrient, mineral and water use efficiency, increased production of phytohormones, induced biotic and abiotic stress tolerance, and minimized toxicity of contaminants (Bacon and White, 2016;Kumar et al, 2017;Harman and Uphoff, 2019;Bhattacharyya and Furtak, 2022).…”

Microbial diversity and their extracellular enzyme activities among different soil particle sizes in mossy biocrust under N limitation in the southeastern Tengger Desert, China

“…The shift in dominance bacteria changes competition and cooperation between species in the bacterial community, impacting the complexity and stability of the bacterial network ( De Vries et al, 2018 ). Additionally, the rhizosphere regulates microbe-facilitated soil processes and services ( Bhattacharyya and Furtak, 2023 ), with plant root-associated secretions playing a key role in the rhizosphere by affecting the growth of microorganisms ( Fan et al, 2017 ). Moreover, previous studies have indicated that biological soil crust has the ability to produce extracellular polysaccharides secreted by filamentous cyanobacteria ( Belnap et al, 2016 ).…”

Improving the Key Enzyme Activity, Conversion Intensity, and Nitrogen Supply Capacity of Soil through Optimization of Long-Term Oilseed Flax Rotation Planting Patterns in Dry Areas of the Loess Plateau of China

“…The soil nitrogen transformation process is mainly affected by soil enzyme activities and the differences in soil microbial communities [37]. The depolymerization process of nitrogen-containing polymers through the involvement of soil enzymes indirectly reflects the soil inorganic nitrogen supply capacity, regulates the soil nitrogen transformation intensity, and increases the soil nitrogen holding rate [13], which is of great significance for maintaining soil fertility and plant growth and development [40]. Optimizing nitrogen management under different rotation conditions is key to improving grain crop yields.…”