Iron deficiency stress effects on total iron in various leaves and nutrient solution pH in sorghum and beans

Abstract Total iron (Fe) concentrations in upper (newly developing), middle, and lower leaves of sorghum [Sorghum bicolor (L.) Moench] and dry bean (Phaseolus vulgaris L.) plants grown with and without Fe were determined for each of the 25 or 27 days plants were grown in treatment nutrient solutions. Lower and middle leaves of sorghum had higher Fe concentrations than upper leaves, but upper, middle, and lower leaves of bean had relatively uniform Fe concentrations. Daily fluctuations of Fe were noted in each group of leaves. Changes in nutrient solution pH were not related to the alleviation of Fe deficiency stress in sorghum, but pH changes appeared to be related to Fe deficiency stress in beans. Iron did not appear to be remobilized from lower to upper leaves in sorghum, but some alleviation of Fe deficiency was noted in beans even though nutrient solutions received no Fe. Rapid increases of Fe accumulation in all leaves were noted in both sorghum and bean when plants received Fe after being in an Fe d...