Bacillus spp.: A bio-inoculant factory for plant growth promotion and immune enhancement

Typically, bio-inoculant could be defined as microorganisms that could be inoculated. Bio-inoculants may include strains of bacteria, fungi, and algae. To date, the use of synthetic chemical pesticides and fertilizers in the agricultural field has been hampering devastating effects to biodiversity globally. Alike to animals, microorganisms could also be extinct as a result of this irresponsible act of human beings. Inadvertently, we may have extinct microbes. Sustained biodiversity may positively result in the production of bio-inoculants. Therefore, research on prospective agricultural bio-inoculants could be the future of sustainable agriculture. Bacillus is one of the most studied bacteria genus in the world. These bacteria could be found in abundance in the environment. Researchers found that these bacteria could be utilized in many fields such as pharmaceuticals, food industry, cosmetics, and agriculture. And it has been benefiting the human population for centuries. However, there are Bacillus spp. that are pathogenic to humans, animals, and plants. Hence, research plays a vital role in discriminating the characteristics of Bacillus spp. suitable to channel it to the right purpose and industry. Currently, the world has realized the importance of sustainable agriculture to cater to the growing population with 7.7 billion people in 2019. To achieve sustainable agriculture, unsustainable conventional practice must be transformed. Thus, the use of bio-inoculant as pesticides and fertilizers could be a stepping-stone to succeed in developing sustainable agriculture that could benefit the longevity of the consumers and most importantly the biodiversity of the Earth. In this chapter, the potential role that played by Bacillus bacteria in sustaining the agricultural industry is explored. The main content is the ability of Bacillus in promoting plant growth and enhancing immune toward plant disease.