Adaptive soil management: A tool for plant fitness in stressful environment through microbial integrity

Abstract

Stresses are the potential threat to principal crop like rice, wheat, maize millets' productivity in all over the world. Events like continuous drought, torrential rains, flooding, heat waves, soil salinity, acidity, metal toxicity and frost damage have been experienced by agriculture. Incidence of invasive weeds as well as plant pathogenic microorganisms may further be increased in coming days due to anthropogenic perturbation and climate change phenomenon. Versatility in crop plant adaptation and appropriate management strategies are required to cope with such stressful condition. Evolving new crop varieties through breeding, screening and selection of potential crops from existing germplasms, crop improvement through biotechnological approaches and exogenous application of osmoprotectants, etc., are the possible mitigation options to be adopted. However, extent and rate of progress in this line is limited. More so, evolving stress tolerant crop varieties through classical and molecular techniques is time taking and consequently expensive. Benefits derived from molecular breeding are also much less uniform and detectable as they depend on microclimate. Current leads suggest gene based technology is not the appropriate approach to develop stress tolerant crop plant. Moreover, one of the potential problems associated with GM crops is that the novel gene might be unintentionally transferred by pollination or by horizontal gene transfer to weeds or soil-borne pathogens leading to the destabilization of the ecosystem. In this background, soil adaptive management strategies those restore the natural resources in soil and combat the abiotic and biotic stresses without hampering crop yield significantly and those impart the whole production system resistance against multiple stresses by exploiting microorganisms and their notable properties of ubiquity, adaptation to stressful environment, species richness and unique ways of interaction with crop plants will be attractive. Building a resistant soil is a crucial element of adaptive soil management in helping farms to adapt themselves to harsh condition. Zero tillage/minimal tillage, cover crops and crop residues incorporation, crop rotation, organic husbandry, legume intercrops, biofertilizer, manure and compost application, site specific and problem oriented crop selection, adjustment in sowing/planting are some ways of adaptive soil management in building soil health resistant to stresses. These practices trigger specific microorganisms to be co-adapted with tolerant crop plants and elaborating biologically active metabolites for better retention of soil moisture and reduce erosion, decrease stresses as well as increase biodiversity in the system inducing better plant growth and thus, help in better stabilization of farm production and income.