Evaluation of nitrogen fertilization of winter wheat
Chwil, S.(Akademia Rolnicza, Lublin (Poland). Katedra Chemii Rolnej i Srodowiskowej)
A field experiment was carried out in 1999-01 on loess soil of pH KCl 6.1 and medium content of available phosphorus and potassium. Uniform fertilization was applied to winter wheat, 30 kg P and 60 kg K/ha, as well as four levels of nitrogen fertilization (0, 85, 170 and 250 kg N/ha. Mineral nitrogen content after extraction with 1 percent K2SO4 was determined after sampling the soil from 0-20, 20-40 and 40-60 cm depths. This study proved the close relation between the amount of mineral nitrogen left after winter wheat harvest and increasing nitrogen fertilizer rates
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