IDENTIFICATION OF RYE CHROMOSOME-5R AS A CARRIER OF THE GENES FOR MUGINEIC ACID SYNTHETASE AND 3-HYDROXYMUGINEIC ACID SYNTHETASE USING WHEAT-RYE ADDITION LINES

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. © 1990, The Genetics Society of Japan. All rights reserved.