Changes in Fe, and Mn Content and Lime Requirement Based on Soil pH Testing in Sweet Persimmon Fields

Sweet persimmon yield can be limited by soil pH. This study was performed to rapidly determine the optimal level of lime requirement in sweet persimmon field. Soil chemical properties such as Fe, Mn, and Zn were analyzed soil samples of 31 sweet persimmon fields at Gyeongnam Province every two months from April to October in 2008. The available Fe, Mn, and Zn content were significantly high top soil (76.5 mg for Fe, 46.1 mg for Mn, and 16.9 mg for Zn, respectively), and subsoil (55.5 mg for Fe, 35.9 mg for Mn, and 12.3 mg for Zn, respectively) in April. Furthermore, the Mn content was significantly decreased since April compared to other micronutrients. We found a significant negative correlation between soil pH and lime requirement (r=0.881, for top soil, and r=0.855, for subsoil). We suggest that a conversion factor is -171 top soil pH + 1,148 to lime requirement (kg ) for top soil, and -190 subsoil pH + 1,247 to lime requirement (kg ) for subsoil in sweet persimmon fields. These results supported that the improvement of lime requirement by soil pH value is necessary to rapidly apply to field, and prevent micronutrients over uptake by persimmon plant.