DESEMPENHO AGRONÔMICO DO SORGO GRANÍFERO ADUBADO COM NITROGÊNIO E FÓSFORO NO SEMIÁRIDO DO RIO GRANDE DO NORTE

Thisstudy aimed toevaluate theperformance agronomic ofgrain sorghumas a functionof Nand- P2O5, as well as the economic analysis in the municipality of Mossoró-RN. The treatmentsconsisted of the combinationof fourN rates(30,60, 90and120 kgha-1) andfourdoses ofP2O5 (30,60, 90and120 kgha-1) and acontrol treatment.The experimental design wasa randomized complete blockwith four replicationsin a factorial design. The characteristicsevaluatedwere:plant height,stem diameter, paniclelength, paniclediameter, dry matter, grain yield, nitrogen and phosphoruscontentinleafnitrogen content, phosphorus in the soil, gross receipts, expendi- tureson fertilizerand net income. Theincreased availability ofnitrogen andphosphorus in thesoil influencethe variables studied, except the nitrogen contentin soil.While mostproductiongrainhas beenestimated for theappli- cation of87.62 kgha-1 N +120 kgP2O5ha-1, the maximumdoserecommendedenvironmentalandeconomic effi- ciencywere60 kgNha-1+ 120kgha-1P2O5.