PHOSPHORUS BIOTRANSFORMATION IN ROOT ZONE OF CORN PLANTS UNDER ACTION OF AHROBACTERYN AND MINERAL FERTILIZERS

Abstract

Objective. To determine the intensity of phosphorus biotransformation in the root zone of corn plants under the action of the microbial preparation Ahrobacteryn and various rates of mineral fertilizers. Methods. Field experiment (on leached chernozem), microbiological (accounting for the number of phosphate-mobilizing bacteria in the rhizosphere of corn plants, biochemical (determination of phosphatase activity, the degree of mobility of phosphates in the rhizosphere soil of plants), statistical. Results. It was found that during the growing season, the number of bacteria that hydrolyze mineral phosphorus compounds and organic soil phosphates increases in the rhizosphere soil of corn plants under the influence of the microbial preparation Ahrobacteryn. Given the features of the influence of mineral fertilizers on the development of phosphate-mobilizing bacteria in the rhizosphere soil of corn plants, it is optimal to use fertilizers in doses not exceeding N90P90K90. At the same time, phosphatase activity of the rhizosphere soil reaches the highest values in the flowering phase; in the phase of milk-wax ripeness of corn grain, the parameters are significantly reduced due to the slowdown in the absorption of phosphorus by plants. The effect of inoculation increases the degree of phosphate mobility in the rhizosphere soil of plants, which is expressed in a decrease in their content due to increased uptake by plants. In the phase of milk-wax ripeness, the mobility of phosphates decreases from 0.42 (in the control without fertilizers) to 0.23 mg P2O5/dm3 of soil solution, which indicates increased absorption of phosphorus by plants. Conclusion. Under the influence of Ahrobacteryn, the processes of phosphorus transformation in the root zone of corn plants are activated, the number of phosphate-mobilizing bacteria increases, phosphatase activity improves and the degree of phosphate mobility, which has an effect on the absorption of phosphorus by plants. As a result, phosphorus removal increases with a crop yield from 51.2 (in the control without fertilizers) to 83.4 kg/ha (with Ahrobacteryn), the efficiency of phosphorus plant nutrition after introduction of N90P90K90 is 62.9 %.