1. Evaluation Of A Controlled Release N-P Fertilizer Using A Modified Drill For Variable Rate Fertilization

Base NP or NPK fertilization is a common practice in cereal production in Chile. Usually, a physical NPK blend is band applied with the seed at planting with the drill. Normal fertilizer rates vary from 400 to 500 kg ha-1; however, there is a tendency in the market to move from physical blend towards chemical blends (monogranule) and, more recently, to controlled release fertilizers (CRF). The CRF are usually recommended at very low rates, varying from 70 to 120 kg ha-1, however this rates are... R.A. Ortega, J.F. Reyes, W. Esquivel, J. Orellana