369 The Determination of Nutritional Status of the Olive Groves in the Aegean and Marmara Regions by Means of Leaf Analyses T. Pekcan, H.S. Turan and S. Ozisik Ministry of Agriculture and Rural Affairs, Olive Research Institute Bornova, İzmir Turkey H. Colakoglu Ege University Faculty of Agriculture Department of Soil Science-İzmir Turkey Keywords: olive, nutritional status, leaf analyses, Aegean Region, Marmara Region Abstract Olives and olive oil are among the main products in the nutrition and health of human beings for centuries. Olive is a cultivated perennial plant having economic importance in the Mediterranean countries, the widest olive growing area, besides Asia, America and North Africa countries which are significant in table and crude oil. Cultural practices and the assessment of nutritional status are important in the yielding capacity of olive trees. This study is conducted with the aim of determining the plant nutrient uptake from the soil to the fruits, branches and leaves of the tree. These studies, carried out in Aegean and Marmara Regions between 1979 and 2003, in relation to macro and micro nutrient contents of olive leaves and the amounts of N, P and K removed by fruit, branch and pit are comparatively presented. As a result, it follows from above mentioned aspects that samples should be taken in stable period for N, P and K, fertilization should be done taking into consideration of amounts of N, P and K removed by pruning, and the fertilizers especially with B and Zn should be applied for micro elements. INTRODUCTION Olive and olive oil is one of the main products in the nutrition and health of human beings for centuries. Olive is a cultivated perennial plant, having economical importance in the Mediterranean Countries, the widest olive growing area, besides Asia, America and North Africa Countries which are significant in table and crude oil. It is known that olive trees are resistant and grown in every condition. However, to increase yielding capacity of olive trees, cultural practices should be done regularly. Nutritional status of olive trees are important in cultural practices. Non-uptake by plant or missing elements in soil should be added. Added mineral fertilizers have effects on yield by changing nutrient status of leaves in the plants. MATERIALS AND METHODS Results of the studies, carried out in Aegean and Marmara Regions between 1979 and 2003, in relation to macro and micro nutrient contents of olive leaves and the amounts of N, P and K removed by fruit, branch and pit were comparatively presented. RESULTS AND DISCUSSION The determination of nutritional status of the plants by means of leaf analyses according to the physical properties and nutrient contents of the soil, the best way to present the nutritional status of the plants is through the amount of nutrients of the leaves. In 1978, Canözer investigated nutrient contents of the leaves in two different categories; low yield year and high yield year. Designated amounts for Canözer were N %, 0.696- 1.975; P %, 0.059-0.155 and K %, 0.130-1.105. Figure 1 shows the results of Eryuce’s diagnosis of N, P, K, Ca and Mg values in low and high yield years and different vegetation periods from 200 olive leaf samples. In 1979, Eryuce investigated the nitrogen values of both leaf and soil. Among October and February nitrogen content is stable, potassium content is stable between Proc. V th IS on Olive Eds.: M.T. Özkaya et al. Acta Hort. 791, ISHS 2008