Puccinia chunjii, a close relative of the cereal stem rusts revealed by molecular phylogeny and morphological study.

A rust specimen with macroscopic similarities to the cereal stem rusts was collected on Elymus sp. from Gansu province, China. Phylogenetic analyses of ITS and COI DNA sequences indicated the fungus was closely related but distinct as a strongly supported sister taxon to the Puccinia graminis species complex. Microscopic examination revealed diagnostic teliospore characteristics, differentiating it from P. graminis and other morphologically similar rusts. Herein, we designate a name for this new lineage, Puccinia chunjii sp. nov.