Ability of ancestral wheat species to secrete mugineic acid family phytosiderophores in response to iron deficiency

Abstract

Mugineic acid family phytosiderophores (MAs) secreted from 19 Fe deficient wild and ancestral species of cultivated wheats were analyzed by HPLC to clarify whether wheat plants have or have not the ability to produce and secrete MAs other than deoxymugineic acid (DMA). Analysis of root washings showed that all the species with a different genome type secreted DMA but not mugineic acid (MA) or hydroxymugineic acid (HMA). This showed that all the species possessing A, B, S or D genomes have the ability to synthesize DMA. The results that even the ancient species do not secrete MA and HMA showed that wheat species have not had the ability to secrete MA and HMA from the beginning of their evolution.

In addition to DMA, an unknown MAs was detected in the root washings of Triticum dicoccum (AABB) and Triticum aestivum cv. N61 (AABBDD). Traces of the compound was also detected in Aegilops bicornis (S^bS^b) and all the species with AABBDD genome. Except Aegilops bicornis (S^bS^b), all the species that secreted the unknown MAs have B genome, and SbSb is proposed to be somewhat related to B genome. Thus the unknown MAs might have originated from a B genome.