Effect of bacteria on the iron uptake by axenically-cultured roots of Fe-efficient and Fe-inefficient tomatoes (lycopersicon esculentum mill.)

Abstract Uptake of 59Fe‐EDTA by axenically‐cultured‐roots of Fe‐efficient and Fe‐inefficient tomato plants in the presence and absence of non‐symbiotic soil bacteria Pseudomonas fluorescens and Arthrobacter globiformis was studied. Under axenic conditions, the iron uptake capacities of the Fe‐efficient and the Fe‐inefficient tomato mutant were equal. Axenic roots, when inoculated with bacteria, showed a fluctuating iron uptake pattern which was nearly parallel with changes in bacterial population during a 16 day observation period. The axenic control roots, however, showed no oscillation in their iron uptake capacity with time. The possible involvement of bacterial siderophores in iron uptake by tomato roots is discussed.