ABSTRACT
Microorganisms grow in the environments suitable for them and make a niche for themselves. Due to the fl uctuations in the nutritional or environmental conditions they face various adverse situations. In order to adjust to such conditions, the microorganisms adapt to the new environment by altering their metabolic profi le. Due to this plasticity, they are able to grow under the changing environment without detriment to growth and development. The availability of excess nutrients or lack of proper nutrients, light (high or low and UV-light), salinity, high solute concentrations (osmotic stress), temperature (high and low), hydrogen ion concentration (high or low pH) and lack of water (drought leading to desiccation) are the common abiotic stresses which microorganisms experience in nature.
