Biochar treatment of peanut rhizosphere nitrogen-fixing bacteria

Biochar plays an important role in the agricultural production process, it can improve soil fertility, promote nutrient uptake and plant growth and development, however, the distribution status of biochar in the soil is an important factor affecting its function. For this reason, we used a greenhouse peanut pot experiment to set up four treatments: control (CK), concentrated biochar application near seeds (B1), relatively concentrated surface application of biochar (B2) and uniformly dispersed application of biochar (B3), to investigate the changes in peanut growth, root morphology, soil nutrient uptake and the structure of soil microbial communities by non-uniform application of biochar. The results showed that the addition of biochar significantly increased the N uptake of peanut aboveground and root system, and reduced the NO3--N and NH4+-N concentrations in soil compared with no biochar application. The B2 treatment significantly increased the net photosynthetic rate and aboveground dry matter weight, which increased by 196.85% and 53.96% compared with the control, respectively, while the B1 and B3 treatments showed the next highest effect; meanwhile, the addition of biochar treatment also At the same time, the addition of biochar treatment also promoted the development of the root system and the number of rhizomes. In terms of microbial and bacterial communities, the addition of biochar increased the number of nitrogen-fixing bacteria to a certain extent, while the relative abundance of soil bacterial communities did not differ much. In conclusion, biochar was able to promote plant growth and development in general, while non-homogenization significantly affected the growth and developmental effects of peanut, with the relatively concentrated surface-applied biochar treatments having the most pronounced effects on improving plant nutrient uptake and root tumor development.