2.3. Bacterial enhancement of tomato growth
One-month old tomato seedlings were transferred to 0.2-strength Hoagland nutrient solution (HNS) at pH 7. The 0.2× HNS contained 6.2 mg L−1 P and 0.2 mg L−1 Fe. For the FePO4 experiment, the 0.2× HNS was provided with only 1 mg L−1 P and no Fe (low P − Fe). For the phytate experiment, the 0.2× HNS was provided with 1 mg L−1 P and 0.2 mg L−1 Fe (low P + Fe). The tomato seedlings were acclimated in 0.2× HNS with (1) low P − Fe or (2) low P + Fe for 35 d. The pH was checked regularly and the volume was maintained to 1 L in aerated containers during the experiment.