Zinc (Zn): Essential for the synthesis of Indole acetic acid (Auxin) activator of carboxylases, alcohol dehydrogenase, lactic dehydrogenase, glutamic acid dehydrogenase, carboxypeptidases and tryptophan synthetase. It is absorbed as Zn2+ ions.
Deficiency: Little leaf and mottle leaf due to deficiency of auxin, Inter veinal chlorosis, stunted growth, necrosis and Khaira disease of rice.
Boron (B): Translocation of carbohydrates, uptake and utilisation of Ca++, pollen germination, nitrogen metabolism, fat metabolism, cell elongation and differentiation. It is absorbed as borate BO3- ions.
Deficiency: Death of root and shoot tips, premature fall of flowers and fruits, the brown heart of beet root, the internal cork of apple and fruit cracks.
