Evaluation of extraction procedures on determination of critical soil and foliar levels of boron and zinc in coffee plants

摘要: Abstract Six‐month‐old coffee plants were grown in the greenhouse pots containing a Dark Red Latosol (Orthox), to study effect of boron (B) and zinc (Zn) on growth leaf content these micronutrients. Boron was added at levels 0, 1, 3, 5 mg kg‐1, whereas Zn proportions 5, 10, 20 kg‐1. application affected total dry matter, height diameter stem, length number plagiotropic branches, leaves, ratio between area leaves (ULA), matter (LAR), moisture, index potential yield (IPY). The IPY, defined as developed flowering buds plus flowers underdeveloped flower flowers, proved be an excellent parameter assess B levels. Leaf B, well correlated with varied from 50 60 Available soils, nig ranged (with critical parentheses): 0.2 0.3 (0.2), ...