Biochemical changes under iron deficiency and recovery in tomato

Exposure of tomato (Lycopersicon esculentum Mill.) plants to Fe deficiency (10 μM Fe) produced chlorosis of young leaves, retarded growth and ind uced changes in enzyme activities and tissue concentration of organic chemical constituents. Compared to Fe sufficient plants, the leaves of Fe-deficient plants showed decrease in chlorophyll concentration, low activity of catalase and high activities of phenolase, acid phosphatase, ribonuclease, alanine aminotransferase and aspartate aminotransferase. Plant exposure to Fe deficiency decreased the concentration of ribonucleic acid, proteins and enhanced the accumulation of phenolic substances and soluble nitrogenous compounds. Compared to Fe sufficient plants, the fruits of Fe-deficient plants were small, matured to a pale yellow colour with low Iycopene and free (titrable) acidity. Supply of Fe-sufficient nutrition to the Fe-deficient plants, about mid point in the life cycle of tomato, reversed the Fe-deficiency induced changes in chlorophyll and catalase activity and the non Fe enzymes-phenolase, acid phosphatase, ribonuclease and aminotransferases and related metabolites to varying extents.