The role of Bacillus subtilis

Bacillus subtilis is a common type of Bacillus. It is mainly distributed in the soil and some decayed organic matter. The presence of Bacillus subtilis can promote the fertility of the land. At the same time, it also has certain antibiotic effects and bactericidal effects, which can promote plant growth. It promotes the respiration of the land and increases its activity, which is beneficial to the growth of crops.

The role of Bacillus subtilis

1. Antibiotic effect

Antibiotic effect refers to the ability of antagonistic microorganisms to inhibit the growth and metabolism of pathogenic microorganisms by producing metabolites at low concentrations, thereby affecting the survival and activity of pathogenic microorganisms. Over the past half century, people have isolated and purified a variety of effective antibacterial substances from the metabolites of different strains of Bacillus subtilis.

2. Lytic effect

The lytic effect of Bacillus subtilis is mainly manifested in that it adsorbs on the hyphae of pathogens, grows along with the hyphae, and then produces lytic substances that cause protoplasm leakage and mycelium rupture; or it produces antibacterial substances that dissolve the cell wall or cell membrane of pathogen spores, causing cell wall perforation and deformity, thereby inhibiting spore germination.

3. Induce plant resistance and promote plant growth

Inducing plant resistance means that Bacillus subtilis can not only inhibit plant pathogens, but also induce the plant's own disease resistance mechanism, thereby enhancing the plant's disease resistance.

Among them, Bacillus subtilis has the strongest stress resistance, the most functions, the widest adaptability and the most stable effect. Bacillus subtilis can produce substances similar to cytokinins and plant growth hormones, which promote plant growth and enable plants to resist invasion by pathogens.

4. Protect the environment

Bacillus subtilis is widely used in biofertilizers. When acting on crops or soil, it can colonize in the rhizosphere or body of crops and have a specific fertilizer effect. At present, microbial fertilizers are used to improve soil fertility, increase the utilization rate of chemical fertilizers, inhibit the absorption of nitrate nitrogen, heavy metals and pesticides by crops, purify and repair the soil, reduce the occurrence of crop diseases, and promote the composting and utilization of crop straw and urban garbage. It plays an irreplaceable role in improving the quality of crop products and food safety.

5. Effect of Bacillus subtilis on the respiration intensity of soil microorganisms

When soil is contaminated by external pollutants, microorganisms may need more energy to survive, causing the metabolic activity of soil microorganisms to respond to varying degrees.

The study showed that Bacillus subtilis treated with various mass fractions showed a stimulating effect on soil respiration, and the greater the mass fraction of Bacillus subtilis in the soil, the greater the stimulating effect on soil respiration intensity, that is, the stimulation intensity was positively correlated with the mass fraction of the applied pesticide.