Effect of Potassium and Magnesium on Leaf Nutrients Concentration of Fruiting Arabica Coffee

Abstract

The effects of potassium and magnesium on leaf nutrients concentration of arabica coffee var. Population#4 (POP4) and Population# 5 (POP5) were examined. Two leve of potassium 1) no potassium applied, 2) soil applied with 300 g of K/tree/year and magnesium i.e. 1) no magnesium applied , 2) 1 % of Mg₂SO₄ sprayed two week interval and 3) soil applied with 150 g/tree/year. The experimental design was Split-Plots in RCBD. It was found that the foliage sprayed and soil applied of magnesium showed magnesium content in the leaves were increased from the marginal point of deficient to adequate. There was no significant interaction between magnesium and potassium neither supplementary nor competitive effects. Other nutrients content also showed no significant difference from different fertilizer application treatments. For the balancing of potassium, calcium and magnesium, it was found that the milli equivalent per 100 grams of dried leaves ranging from 79.25-122.34 (adequate rang are 130-170) for potassium and calcium were in suitable range, while magnesium was lower than the standard, resulted in the low range for total aggregation.