Biotechnological Insights into Cold-Stressed, Adapted Microorganisms for Plant Health and Soil Improvement

Cold stress is one of the key abiotic stresses that has an adverse impact on plant growth and fitness. More than 85% of the Earth’s biosphere has temperatures below 5 °C throughout the year, which causes water to freeze in the soil. Frozen soil and cold or frozen water make it hard for plants to thrive, ultimately affecting the overall yield and productivity. Further, the low temperature also causes cellular damage and the generation of reactive oxygen species (ROS), which hamper several biochemical and physiological pathways at the molecular level and affect cell survival in plants. However, there are special classes of microorganisms known as psychotropic microbes that have the ability to grow at 0 °C and are adapted to extremely cold environments. They are ubiquitous in nature, have several kinds of modifications in their cell wall to tolerate extreme cold, and can metabolize at low temperatures utilizing potent cold-active enzymes (CAE) that can degrade diverse organic waste substrates, including cellulose, lignin, and lipids. Interestingly, they also help plants by promoting their growth and development. Thus, this ability of these microorganisms makes them an important class that can be utilized to promote plant growth and soil improvement in the agricultural field. Hence, this chapter focuses on recent breakthroughs in biotechnological insights into cold-stressed, adapted microorganisms for plant health, soil improvement, and crop productivity. Similarly, in this chapter, we update and analyze the future consequences associated with cold-stressed, adapted microorganisms and their possible application in sustainable agriculture.