grapevine, nitrogen fertilization, total nitrogen, free amino nitrogen, ammonia
Abstract
Nitrogen fertilization is one of the common agrotechnical practices in vitculture, by which we can achieve higher content of nitrogen compounds in grapes. The purpose of this research was to determinate the influence of nitrogen fertilization on total nitrogen, free amino nitrogen and ammonia composition in grapes of Chardonnay, Italian Riesling and White Riesling cultivars. Research was laid out in the 2006 and 2007. Experiment was random block design with 3 repetitions, and fertilization was in the form of urea, as follows: 0 kg/ha - K, 51 kg/ha (23 kg N/ha) –N1, 152 kg/ha (70 kg N/ha) – N2 te 254 kg/ha (117 kg N/ha) –N3. The grapes were harvested according to repetitions. The obtained research results indicated a positive effect of nitrogen fertilization on all of examined nitrogen compounds.
