NODULATION IN BEAN UNDER SOLUBLE PHOSPHORUS SOURCES WITH AND WITHOUT POLYMER

The availability of nutrients can affect the establishment of nodulation, among these, it is worth mentioning phosphorus (P). The impediment of fixation allows the availability of this element to be greater for the absorption of the culture. Thus, the objective was to evaluate the effect of two sources of phosphate fertilizers with and without polymer coating on nodulation in common bean. The experiment was carried out in a greenhouse, in the city of Patrocínio, using pots with a capacity of 3.8 dm³, and the soil was collected at a depth of 0-20 cm. The experiment was set up in a randomized block design, where the treatments consisted of the application of 70 kg ha-1 of P2O5 in the form of monoammonium phosphate (conventional and polymerized - Kimcoat®) and single superphosphate (conventional and polymerized - Kimcoat®) and the control, with four repetitions. The seeds were inoculated with Rhizobium tropici, strain SEMIA 4088. The nitrogen (N) dose was adjusted to 40 kg ha-1 and the potassium fertilization to 20 kg ha-1 of K2O for all treatments applied at planting. The evaluation was carried out at 35 days after plant emergence, measuring the production of shoot and root dry matter, number of nodules and leaf N and P content. Conventional MAP showed greater efficiency in increasing nodulation, mass shoot dry mass and root dry mass for the crop. The polymerized phosphate sources did not influence bean nodulation. The polymerized MAP resulted in the highest foliar N content. Regardless of the source, there was an increase in leaf P content. It was concluded that the polymerized phosphate sources did not influence the nodulation of the culture.