Phylogenetic study of indigenous grapevine leaf rust fungi in North America and biological identity of an invasive grapevine leaf rust fungus in Brazil.
Two American grapevine leaf rust (GLR) fungi, Phakopsora muscadiniae and P. uva, were found to be phylogenetically different from Asian-Australasian GLR fungi. In the phylogram based on rDNA region sequences, a clade of the American fungi was sister to an inclusive clade of three autoecious species on Meliosma and a heteroecious species host-alternating between Meliosma and Parthenocissus. An invasive Brazilian GLR fungus (as P. meliosmae-myrianthae) was included in the Asian-Australasian GLR fungi clade, or the clade of the Thai population of Phakopsora sp. It could be assumed that the Brazilian GLR fungus originated from an inadvertently introduced Thai population.