Determination of the effects of phylloxera and different nitrogen doses on the grapevine morphological and physiological characteristics of grape

Today, there are two key factors limiting grape growing; phylloxera and nitrogen deficiency. In the world, there has been no pesticide found yet to be used efficiently to control phylloxera. Therefore, modern viticulture can be done with grapevines grafted on American rootstocks being resistant to this pest. Within these vineyards, the factor causing maximum loss of efficiency and quality is the nitrogen deficiency. In this study, it is aimed at analyzing effects of phylloxera (Daktulosphaira vitifoliae Fitch) and nitrogen deficiency on morphological and physiological characteristics of grapevines of Riesling variety and Teleki 5C rootstock. For this purpose, plants are taken for testing, growing in 3 L pots within a fully automated, glass-made greenhouse environment. On grapevines, 4 different applications were carried out under following conditions; 1) Phylloxera infected Phy (+) 2) Phylloxera noninfected Phy (-) 3) sufficient amount of nitrogen N (+) 4) insufficient amount of nitrogen N (-).As a result of this research, effect of these treatments on grapevines' morphological and physiological characteristics at the were statistically significant. For Teleki 5C rootstock and Riesling type grapevine, in case of N (-) nitrogen deficiency and for Phy (+) phylloxera positive plants, lower values were found in terms of size of plant, number of leaves, fresh and dry weight of plant, SPAD, Handy Pea Photosynthetic parameters as well as leaves' N, C, P, K, Fe, Zn, Cu and Mn concentrations compared to control group.