As shown in Fig. 1, the level of Fe in the growth medium clearly
affected the chlorophyll synthesis of spinach plants. The Fe-omitted
treatment (0 lM FeEDTA) resulted in the strongest inhibition
of chlorophyll synthesis with the concentration only at about
0.6 mg per gram of newly-formed blades. In the mild Fe-deficient
treatment (1 lM FeEDTA), the chlorophyll synthesis was also
inhibited compared with two relatively higher Fe treatments (i.e.
10 and 50 lM FeEDTA). The chlorophyll concentration of the mild
Fe-deficient higher than that of the Fe-omitted treatment. This result
was found to be statistically significant