The great Bacillus subtilis

Bacillus subtilis is a species of Bacillus, widely distributed in soil and decaying organic matter, and is also a common endophytic bacteria in plants. In addition, it grows fast, has simple nutrition, and can produce heat-resistant and stress-resistant spores. Therefore, it is found in many bacterial fertilizers (agents).

Of course, the widespread use of subtilis spores also benefits from its powerful role in enhancing crop resistance, promoting crop growth, improving soil, and improving crop quality. It can be said that when used well, it is both a medicine, a fertilizer, and a plant growth regulator.

①Improving the soil

The improvement of soil by Bacillus subtilis is mainly manifested in regulating soil nutrients, changing the structure of soil microbial flora, and decomposing soil residual pesticides.

Regulation of soil nutrients: Bacillus subtilis and its secretions can accelerate the mineralization and release of nitrogen, phosphorus and potassium, thereby increasing soil nutrients. However, the growth and reproduction of Bacillus subtilis will consume organic matter in the soil, so it is recommended to use it with organic fertilizer.

Change the structure of soil microbial colony: in healthy soil, the number of bacteria > the number of actinomycetes > the number of fungi, but when the soil problem is serious, the number of some fungi such as Fusarium, Botrytis cinerea, and Verticillium dahliae will increase, while A variety of soil-borne diseases are induced, and the colonization of Bacillus subtilis can change the structure and diversity of soil microorganisms in the root zone of crops. The number of bacteria and actinomycetes increases significantly, and the number of fungi decreases significantly.

Decomposition of residual pesticides in soil: Bacillus subtilis can help degrade substances harmful to plant growth such as some herbicides, phoxim, profenofos, etc. by increasing the activities of urease, protease, invertase, etc. in the soil.

②Regulate the growth of crops

On the one hand, Bacillus subtilis can promote crop growth; on the other hand, Bacillus subtilis can improve disease resistance.

Promote crop growth: Citrus subtilis improves the soil to create a good environment and nutrient conditions for the root system of crops. In addition, the secretion of active substances by Bacillus subtilis can stimulate the proportion of endogenous hormones of crop growth type to increase, such as the increase of indole acetic acid and gibberellin, and the decrease of abscisic acid, which helps to increase production and income.

Improved disease resistance: We mentioned earlier that Bacillus subtilis can reduce the number of pathogenic microorganisms in the soil, but this is only part of its disease resistance.

Bacillus subtilis has the ability to colonize and can successfully colonize the roots, stems, leaves and soil of crops. When the colonization amount reaches a certain level (10^4 CFU/g), it can prevent pathogenic bacteria by occupying space and nutrients. Infection and damage to crops.

At the same time, Bacillus subtilis can produce active substances such as antibiotics and antibacterial proteins after colonization, which causes the mycelia to distort, swell and deform, thereby inhibiting the growth of pathogenic bacteria and achieving disease control.