engleski

Long-term effects of organic fertilizers on macroelements status in grapevine leaf on calcareous soil

Growing grapevines on calcareous soils often leads to plant nutrition dissorders. Vineyard fertilization practices on such soils diff er signifi cantly from the fertilization on acid soils because of infl uence of free calcium and high pH on the availability of nutrients. Three year trial was set up according to randomize complete block design with 6 treatments (unfertilized, farmyard manure 20 t ha-1 and 40 t ha-1, peat 20 000 L ha-1 and 40 000 L ha-1, NPK 5-20-30 500 kg ha-1+200 kg UREA kg ha-1) in 4 repetitions. Samples of grapevine leaves were taken three times during the growing period: at the fl owering, two weeks after fl owering and at the verasion. Total nitrogen was determined by the Modifi ed Kjeldahl method, phosphorus was determined spectrophotometrically, potassium fl amephotometricaly and calcium and magnesium atomic absorption spectrometricaly. Signifi cant eff ect of fertilization was determined in the fi rst year of the study on the amount of calcium (two weeks after fl owering) and in the third year on the amount of potassium (fl owering). Fertilization did not signifi cantly aff ect the amount of nitrogen, phosphorus and magnesium in grapevine leaves.

grapevine, nitrogen, phosphorus, potassium, organic fertilizers

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