Physiological and biochemical changes in young maize plants under iron deficiency I. Growth and photosynthesis

Young maize plants, grown hydroponically, were supplied with different amounts (7.5, 0.75, 0.15, 0.075, and 0 mg Fe/L) of iron (Fe). At 14, 21, and 28 days, parameters characterizing growth and photosynthesis were determined. Iron‐deficiency resulted in significant changes in biomass accumulation and distribution between vegetative organs as well as changes in the content of chlorophyll a, chlorophyll b, and the carotenoids. The photosynthetic rate per leaf area was decreased. Part of ¹⁴C incorporated in low molecular compounds was increased and the share of amino acids and organic acids in them was increased. Plants supplied with 1/10th of the optimum Fe required partially adapted to the Fe deficiency. Plants with visual symptoms of Fe deficiency showed some peculiarities as compared to those plants severely Fe‐deficient.