A. series of laboratory and greenhouse experiments were conducted to
evaluate ionic compound. formed between urea and essential micronutrient through
complexation reaction: Results revealed that lhe addition of metal salt urea without
organic matter, slightly increased the pH of the soil. At the beginning of the incubation,
citric acid enhanced the E.C. of the soil arid gradually increased up to 28 days of the
incubation. Results also showed that the adoltlon of metal salt urea complexed
improved the characterization of modified slow release fertilizers through allowing a
steady hydrolysis of urea to the soil over a period of six weeks. The addition of Fe or
Mn to complexes urea increaseid the availability of iron and manganese in the soil.
Citric acid addition gave the highest value of Fe and Mn as compared without citric
acid. If was observed that the addition of complexes metal salt urea with citric acid
had significantly increased fresh and dry weight of the lettuce plant with gradually
increased in .the presence of organic matter at different stages of the growth. Higher . value of fresh and dry matter production were recorded in the presence of citric acid
.due to improving of the fertilizer complexing salt urea mechanisms. . . . The application of complexing metal salt urea had a positive effect for
maintaining Fe in· an active form as Fe?+ in leaves of the lettuce plants reflecting on
the increasing 'of chlorophyll content to an extent of healthy plants and thus the ability
to overcome the adverse effects of high pH and other ions in soil and then correcting
iron chlorosis particularly in newly reclaimed soil.