Abstract: | This study was implemented to determine effectiveness of various treatments in recovering boron (B)–deficient olive trees in the Marmara region. The study was carried out during the period 2000–2005. The experimental soil was in loamy texture with medium alkaline pH, low organic matter, and low B concentration. The experiment was conducted in a randomized plot experimental design with 12 treatments. In the study, different B fertilizers were applied to soil and leaves. Treatments of 125, 250, and 500 g?1 borax (sodium tetraborate) were applied to the soils at the beginning of the experiment to determine the later effects of sodium tetraborate. Treatments of 125, 250, and 500 g borax were applied to the soils every year in March. Also, 0.4% borax was applied two or three times, 0.8% sodium tetraborate two or three times, and 0.5% bor-track (boron ethanol amine) two times by foliar applications during the growing period. According to the results, two applications of 0.4% sodium tetraborate to the leaves gave the best results. Soil applications of 250 g sodium tetraborate every year and 500 g sodium tetraborate every two years were the most effective treatments. |