Methods for estimating zinc availability to olive grown soils in Bursa region

This research was conducted in order to determining the most appropriate Zn extraction method for olive grown soils in Bursa region. For this purpose, soil, leaf and fruit samples were taken from 50 different olive orchards in Bursa region. For the determination of the available zinc contents in the soils, seven different methods were used; (M1) 3 HCl+ 1 HNO3; (M2) 0,005 M DTPA + 0,01 M CaCl2 + 0,1 M TEA;(M3)0,01 M HEDTA; (M4) 0,1 N HCl; (M5) 0,01 M Na2EDTA + 1 M (NH4)2CO3; (M6) 0,01 N Na2EDTA ve (M7) 1 N NH4OAc. The relationships of the methods of M1, M2, M3, M5 and M6 in the soils and Zn in the leaves produced significant correlation coefficients. Statistically significant relationships were found between extraction methods of M2, M4 and M7 and Zn in the fruit samples. It was concluded that, methods of M2, M4 and M5 could be used for the determination of available Zn contents in olive orchards in Bursa province. As a result, M2 (DTPA) could be used to determine contents of the examined soils due to, existing sufficiency levels, being commonly used methods, at the same time possibility of determination of other micro nutrients besides Zn in the soil.