Nutrient management analysis in field pea (Pisum sativum L.) cultivated in the no-tillage technology

The object of study was to analyse nutrient management (nitrogen, phosphorus, potassium) in pea (Pisum sativum L.) cultivated in the no-till technology. The trial was established in the years 2001–2003 on gleyic Fluvisol (locality Milhostov). The territory has continental character of climate with average precipitation for year 559 mm, for vegetation period 348 mm and with average daily temperature for year 8.9 deg C, for vegetation period 16.0 deg C. The field treatments with field pea were realized in natural conditions without irrigation. Sowing was realized by equipment Great Plains with sowing rate 290 kg per ha. There were two variants of fertilization compared in the trial, fertilized (25 kg per ha N, 30 kg per ha P a 40 kg per ha K) with non fertilized. The results show that the deficit of observed nutrients was not found in condition with mineral fertilizers. Balance of nitrogen, phosphorus and potassium was positive (+23.97 kg per ha per year N, +18.36 kg per ha per year P and +23.28 kg per ha per year K) and its compensation amounted 157.54%, 238.46% and 177.45% respectively. Important holding in positive balance had N2-fixation. Quantities of N2-fixation calculated in straw and root remains were in average 21.64 kg per ha N. Air nitrogen provides for positive balance of nitrogen in condition without mineral fertilization as well, with average input 16.76 kg per ha N. Nitrogen balance was +3.81 kg per ha per year and nitrogen compensation achieved level of 111.93%. Phosphorus and potassium balance in condition without mineral fertilization was negative. Deficit of phosphorus represented 8.53 kg per ha per year (compensation 15.96%) and deficit of potassium represented 9.24 kg per ha per year (compensation 59.08%). Despite the negative balances of phosphorus and potassium (in conditions without mineral fertilization) we can prove that field pea cultivation in no-tillage technology did not reduce the content of available nutrient in the soil.