Slavol for soybean influences the establishment of symbiosis between soybean root and Bradyrhizobium japonicum and the formation of nodules. Bradyrhizobium japonicum enters inside of the root (parenchyma) through root hair, where they start multiplying rapidly, resulting in the formation of nodules. Nitrogen-fixing bacteria live in the nodule and transfer nitrogen directly to the plant, and the plants supply the bacteria with nutrients they produce in the photosynthesis process.
Associative nitrogen-fixing bacteria and phosphorus mineralizing bacteria belong to the group of bacteria that stimulate plant growth - colonize the soybean root, positively influencing plant nutrition with nitrogen and phosphorus. These bacteria produce auxins (indol-3- acetic acid) that help the establishment of symbiosis, i.e. bacteria penetration through root hair to the root parenchyma, where they form nodules.