Molybdenum-Manganese-Iron Antagonisms in the Nutrition of Tomato Plants.

Abstract

Fe deficiency symptoms and decreased yields of tomatoes induced by high concentrations of Mn in nutrient solution cultures were accentuated by Mo additions. This is in direct contrast with other published results. In agreement with the chlorosis symptoms and weight data, the Fe content of the tissue also decreased with increasing concentrations of Mo in the nutrient medium. Further experiments on Fe-Mo antagonisms showed that as little as 0.67 ppm Mo induced Fe chlorosis and reduced growth. Although not conclusive, results indicated high concentrations of Fe also can accentuate Mo deficiency. It is proposed that the Mo-Fe interaction is due to formation of an Fe-Mo precipitate of very low solubility in the roots which makes Fe unavailable to the top growth. The significance of the results in terms of plant nutrition and agriculture are discussed.