Microbial Biostimulants for Plant Growth and Abiotic Stress Amelioration, the latest release in the Biostimulants and Protective Biochemical Agents series, provides readers with insights into the major role of biostimulants in plant growth and development while under abiotic stress. The term biostimulants is broadly used to reference a group of diverse substances and microorganisms that stimulate life or that promote favorable plant responses. They stimulate natural processes to enhance/benefit nutrient uptake, nutrient efficiency, tolerance to abiotic stress, and crop quality. Many biostimulants improve nutrition and they do so regardless of their own nutrient contents. Further, recently microbe-based biostimulants have emerged as important plant protectors under a range of adverse conditions.