Abstract
Using Imperial rye chromosome addition lines of wheat, we identified the rye chromosome that carries the gene for mugineic acid (MA) synthetase catalyzing synthesis of MA from 2'-deoxymugineic acid (DMA) and the gene for 3-hydroxymugineic acid (HMA) synthetase catalyzing synthesis of HMA from MA. Plants of seven addition lines, Chinese Spring wheat and Imperial rye were water-cultured, and chlorosis was induced by depletion of Fe from the culture medium. The root-washing from each plant was analyzed with HPLC to detect mugineic acid-family phytosiderophores (MAs). Chinese Spring wheat secreted only DMA, while Imperial rye secreted DMA, MA and HMA. In the case of addition lines, a 5R addition line secreted DMA, MA and HMA, but the others secreted only DMA. Therefore, 5R of Imperial rye was concluded as a carrier of the two genes which encode enzymes that catalyze MA-synthesis from DMA and HMA-synthesis from MA.
