Favorable soil moisture and fertilization model for tobacco cultivation

This study was conducted to provide a quantitative fertilization model for producing high quality tobacco leaves and reducing environmental pollution and the quality decline of tobacco leaves resulted from over-fertilization. A mathematic model for the relations of tobacco output value with nitrogen, phosphorus, potassium and water factors was established by the potted experiment. The interaction among factors was analyzed, the model was optimized, and the contribution ratios of soil nitrogen, phosphorus, and potassium were calculated. Furthermore, a fertilization model was developed and tested in a field experiment. Results show that the optimum fertilization amounts of pure nitrogen, P2O5, K2O are 4.85-5.45 g, 7.68-8.64 g, 16.17-17.95 g, respectively. The favorable soil moisture is 75.8%-80.5% in potted experiment. The recommendation amounts of pure nitrogen, P2O5, K2O based on fertilization model are 39.30- 44.16 kg/hm², 64.30-72.34 kg/hm², 232.77-258.41 kg/hm², which coincide with the results of field experiment. The optimum fertilization amounts of pure nitrogen, P2O5, K2O are (42.86±7.49) kg/hm², (65.09±12.58) kg/hm², (242.68± 8.69) kg/hm².