Diagnosis of Boron Deficiency in Green Dwarf Coconut Palm

Abstract

The diagnosis of boron deficiency in coconut palms has been hampered by lack of information about its distribution in the plant. Two experiments were conducted, one in a greenhouse to in- duce boron deficiency in dwarf green coconut palms, and other in the field, in which the plants re- ceived doses of boric acid, B(OH)3. The objective was to verify symptoms of boron deficiency and boron content variation in canopy, leaves and folioles (or leaflets). Boron deficient plants led leaves and folioles to become deformed. The deficient and sufficient contents of boron varied sig- nificantly in the canopy, but did not vary in leaves. The boron content increased significantly from bottom to the apex of the folioles in both treatments. To survey the level of boron in the coconut palm, the ideal is, using samples taken from the youngest leaf, to calculate the relation between the boron content in the apex of the foliole and the content in the center or in the folioles bottom, with minimum values 2.2 or 2.7, respectively.