An Overview of Bacillus Species in Agriculture for Growth Promotion, Biocontrol and Dry Tolerance
Abstract
Each year, millions of tons of chemicals and pesticides are applied to agricultural soils to support food production. However, this intensive use of chemical inputs depletes soil vitality, reduces moisture retention capacity, and raises significant environmental and health concerns. To mitigate these negative impacts, researchers worldwide are seeking alternative agricultural solutions that reduce reliance on chemical inputs. One promising approach is the application of rhizobacteria, which can restore soil health, control plant pathogens, and promote plant growth through various mechanisms. Notably, different Bacillus rhizobacteria species play key roles by producing hormones, enzymes, antibiotics, and siderophores that enhance plant growth and protect against pests. Additionally, Bacillus spp. form beneficial interactions with crops, boosting plant tolerance to environmental stresses. Despite their potential, the agricultural applications of these bacteria remain underexplored, with only a limited number of species currently in direct use, leaving much of their potential untapped. A deeper understanding of Bacillus spp. biology is essential to developing products that can drive sustainable biotechnological innovations in agriculture and industry. This article reviews the role of Bacillus spp. and the effective utilization of plant growth-promoting (PGP) variants in agricultural systems, while also highlighting the critical, yet understudied, aspects of rhizobacteria that should be prioritized in future research.