Soil microbes: A key player on soil health and crop production under changing climate

Climate is one of the main drivers of organism growth and species distributions; thus, a changing climate has the potential to alter the composition of plant and soil communities and the interactions between them. Soil microorganisms represent a fundamental role in soil health and sustainability. Microbial population density and diversity are stirred by the level of organic matter indirectly by providing energy for soil micro- organisms, improving soil moisture, soil structure and stability, plant nutrient availability and forbid soil-borne disease incidence. Crop production and soil management practices designed to hold soil microorganisms i.e. minimum tillage, composting, cover cropping, eliminating fertilizer and pesticide use and maintaining biodiversity, will inevitably lead to soil improvements and stability. The need for replenishing organic matter in the soil after harvesting is thus of great importance. In ecological farming systems, organic matter is maintained by mixed farming, rotations, recycling, compost and farm yard and green manures and bought-in organic sources. Including legumes and cover crops in the rotation should help balanced soil fertility, disease management, and avoid leaching nutrients and soil pollution. Crop and soil management practices designed to support soil microorganisms have been shown to lead to improvements in soil structure and stability. Although the great diversity of soil microorganisms is now well appreciated, studies over the past twenty years have established that several other soil organisms, apart from mycorrhizal fungi, not only play an active role in suppressing pathogens but also mediate the activity of a range of beneficial organisms. Apart from farming in ways that support indigenous microbes, the use of effective exotic cultures of beneficial microorganisms as soil and compost amendments, root dips, feed additives or sprays to supplement or reinforce the indigenous micro-flora are being considered.