Leaf content of macro and microelements in Vitis vinifera cv
- M. Petek, D. Gluhić, M. Herak Ćustić, L. Čoga, T. Ćosić, S. Slunjski
- Sauvignon Blanc. VI ISHS International Symposium…
Infl uence of soil reaction on phosphorus, potassium, calcium and magnesium dynamics in grapevine was studied on the variety Sauvignon Blanc in 2007, in the Plešivica wine-growing region. Investigations were conducted on three vitisol subtypes: dystric cambisol (pHKCl 3.73-3.76), pseudogley (pHKCl 4.67-4.69) and rendzina on marl (pHKCl 7.21-7.27). To establish the amount and dynamics of P, K, Ca and Mg in plant material, leaf samples were taken three times during the growing period: at the fl owering and veraison stages and at the end of the growing period. At all sampling times, signifi cantly higher leaf contents of P, Ca and Mg were found on alkaline soil compared to acid soils, while diff erences in K levels were not statistically signifi cant. Diff erences in P contents may be explained by better solubility and thereby better availability of P from Ca-phosphates compared to Al, Mn and Fe-phosphates in acid soils. In addition, the cation ratio K/(Ca+Mg) that has a signifi cant infl uence on grape quality, was also determined in leaves. Compared to optimal values (0.30–0.40), the least favourable ratio K/ (Ca+Mg) was recorded at fl owering on acid soils (0.38–0.77) and at harvest on calcareous soil (0.12–0.27). Diff erences in the content of sugar and total acids in must indicate a positive correlation between leaf contents of P, Ca and Mg and sugar content of must, and a negative correlation between leaf contents of P, Ca and Mg and the total acid content of must.