Leaf macronutrient composition of grapes in South plain Hungarian vineyards

In our study analysis of samples of vine leaves taken in the different phases of vegetation was carried out in three years, 2010-2012. Our analysis confirmed the translocation of nutrient elements in varying degrees. Laboratory tests were made on about eight thousand leaf samples in our laboratory (Soil and Plant Testing Laboratory of Faculty of Horticulture, Kecskemét College). The results of sample tests, largely arriving from the Southern Hungarian plain region, mainly Bács-Kiskun county, showed that the level of the main nutrient elements from bloom to the completion of maturation tends to decrease. In the case of phosphorus, a continuous slow decline was shown, while N and K varied according to a curve; increase in the beginning of ripening and significant decrease afterwards. Changing in the ratios of some main nutrients (N/K and K/Mg) was also shown. Low level of potassium and phosphorus was observed in about one fifth of the samples, so increase in P and K fertilization may be proposed