Dactylonectria and Ilyonectria Species Causing Black Foot Disease of Andean Blackberry (Rubus Glaucus Benth) in Ecuador

Abstract

Andean blackberry (Rubus glaucus Benth) plants from the provinces of Tungurahua and Bolivar (Ecuador) started showing symptoms of black foot disease since 2010. Wilted plants were sampled in both provinces from 2014 to 2017, and fungal isolates were obtained from tissues surrounding necrotic lesions in the cortex of the roots and crown. Based on morphological characteristics and DNA sequencing of histone 3 and the translation elongation factor 1α gene, isolates were identified as one of seven species, Ilyonectria vredehoekensis, Ilyonectria robusta, Ilyonectria venezuelensis, Ilyonectria europaea, Dactylonectria torresensis, or Dactylonectria novozelandica. Pathogenicity tests with isolates from each species, excluding I. europaea and D. novozelandica whose isolates were lost due to contamination, confirmed that the four species tested can produce black foot disease symptoms in Andean blackberry. This is the first report of Dactylonectria and Ilyonectria species causing black foot disease of Andean blackberry.