Ecological speciation within thePhytophthoragenus

AbstractOver the past few years, symptoms akin to late blight disease have been reported on a variety of crop plants in South America. Despite the economic importance of these crops, the causal agents of the diseases belonging to the genusPhytophthorahave not been completely characterized. In this study, we used an integrative approach that leveraged morphological, ecological, and genetic approaches to explore cryptic speciation withinP. infestans sensu lato. We described a newPhytophthoraspecies collected in Colombia from tree tomato (Solanum betaceum), a semi-domesticated fruit. All morphological traits and population genetic analyses, using microsatellite data and a reduced representation of single nucleotide polymorphism (SNP) data, support the description of the new species,Phytophthora betaceisp. nov. We have demonstrated that ecological differences are important in the persistence ofP. infestansandP. betaceias genetically isolated units across an overlapping area in the northern Andes.