Enhancement of Fe availability by PDMA in the rhizosphere of peanut
The effects of PDMA on the Fe levels in peanut plants and the peanut rhizosphere are shown in Fig. 2. Plants treated with PDMA and PDMA–Fe displayed higher active Fe concentrations in young leaves, increased by 54.5% and 48.7% compared with the control, respectively, and these two treatments produced slightly higher results than did treatment with EDTA–Fe (Fig. 2a). Moreover, PDMA and PDMA–Fe significantly enhanced the level of available Fe in the rhizosphere by 25.5% and 19.1%, respectively; in contrast, Fe availability in the rhizosphere was not influenced by EDTA–Fe (Fig. 2b). The results above indicate improvements in the availability of soil Fe and Fe nutrition in peanut plants grown in calcareous soil due to PDMA or PDMA–Fe treatment.