Effect of Al on the phytosiderophore-mediated solubilization of Fe and uptake of Fe-phytosiderophore complex in wheat (Triticum aestivum) |
| |
Authors: | Yi-Chieh Chang Jian Feng Ma Takashi Iwashita Hideaki Matsumoto |
| |
Institution: | Research Institute for Bioresources, Okayama University, Chuo 2-20-1, Kurashiki 710, Japan; Faculty of Agriculture, Kagawa University, Ikenobe, Miki, Kagawa 761-0795, Japan; Suntory Institute for Bioorganic Research, Shimamoto-cho, Mishima-gun, Osaka 618, Japan |
| |
Abstract: | The effect of Aluminum (Al) on phytosiderophore-mediated solubilization of insoluble Fe and the uptake of phytosiderophore-Fe3+ complex was examined in wheat ( Triticum aestivum L. cv. Atlas 66). Al addition did not affect the Fe solubilization by 2'-deoxymugineic acid (DMA), although Cu addition significantly inhibited the solubilization capacity. Addition of ten times more Al than Fe to the solution of DMA-Fe3+ complex did not decrease the absorption of the DMA-Fe3+ complex at 375 nm. Furthermore, NMR study indicated that Al did not shift the proton chemical shifts of DMA. All these results suggest that Al could not form a complex with the phytosiderophore, and is thereby unlikely to affect the process of phytosiderophore-mediated solubilization of Fe. Exposure of root to Al up to 100 μ M for 3 h did not inhibit the DMA-Fe3+ uptake by the roots, but longer pretreatment (>6 h) inhibited the uptake of the DMA-Fe3+ by more than 50%. Neither the uptake of DMA-Fe3+ nor root elongation was inhibited by 24 h pretreatment with 10 μ M Al, but both uptake and root elongation were inhibited by higher Al (>20 μ M ) pretreatment. These results suggest that Al did not directly block the transport of the phytosiderophore-Fe3+ complex, and that the decreased uptake of the phytosiderophore-Fe3+ complex resulted from the roots being damaged by Al. |
| |
Keywords: | |
|
|