STATUS OF NUTRIENTS IN VINEYARDS OF ĆEMOVSKO POLJE SUMMARY The results of investigation of nutrient status in vineyards of Ćemovsko

The results of investigation of nutrient status in vineyards of Ćemovsko polje are shown in this paper. In order to provide a more reliable basis for the definition of relationships between grapevine (nutrients in leaf petiole – P, K, Ca, Mg, Fe, Mn, Cu and Zn) and soil properties (pH, total carbonates, humus (organic matter), exchangeable Mg and available P, K, Fe, Mn, Zn and Cu), factor and correlation analyses were applied. In the top layer (0 – 30 cm), investigated highly calcareous and alkaline soil had high concentration of nutrients, exceptionally for iron which was on the limit between low and medium level, and for phosphorus on low level. In the underlying soil layer (30 – 60 cm), nutrient contents were low. The content of Cu was very high in the both soil layer, due to its accumulation through agronomic practice, where Cu as a common ingredient of the plant protection products used especially in vineyards. In average, the level of P, K, Ca, Mg, Zn and Cu in leaf petioles indicated optimal supply of grapevine. However, the deficiency of Fe and Mn was detected. A common cause of chlorosis is a deficiency of these elements, which are of crucial importance for photosynthesis.Four factors determining soil chemical characteristics were identified by factor analysis. They accounted for about 78% of the total variance. The communalities of parameters, considering four factors, varied from about 59% for available K to 85% for humus and exchangeable Mg. Two main factors represented the statuses of: 1) mutually complementary available fraction of Zn and Mn (positive pole) and pH and carbonate (negative pole), and 2) humus and available Fe. Directly proportionality was found between the content of Mn in petiole and the score of first factor (p = 0.037). It means that the status of Mn in grapevine depends directly on the available fraction of Mn in soil (DTPA-Mn), as well as indirectly on the pH value and CaCO3 content. The availability of Fe (DTPA-Fe) depends on the content of humus, since positive statistically significant (p = 0.015) correlation was found. The management practices which can influence on availability of Fe and Mn are the increase of organic matter (humus) and modification of the soil pH. The applications of fertilizers containing Fe and Mn through leaves or soil are recommended.