Canker disease caused by Chrysoporthe doradensis and C. cubensis on Eucalyptus sp. and Tibouchina spp. in Brazil

Abstract

Chrysoporthe species are known to cause canker on hosts belonging to Myrtaceae and Melastomataceae families. Cankers occur on tree trunks and branches and may reduce growth and lead to plant death. In this study, the incidence and pathogenicity of Chrysoporthe cubensis and other species causing canker on Eucalyptus sp., Tibouchina heteromalla and T. granulosa were examined. The isolates were collected in Maranhão (MA) and Minas Gerais (MG) in Brazil. Sequence analysis of beta-tubulin and actin genomic regions confirmed the presence of C. cubensis and C. doradensis on clones of the hybrid Eucalyptus grandis x E. urophylla, T. granulosa, and T. heteromalla in Brazil. Morphological characterization enabled the identification of the isolates from both genera primarily based on differences in conidial size and shape. The isolates were pathogenic to ten Eucalyptus clones and Tibouchina plants. Our results contribute new knowledge of Chrysoporthe species causing diseases of woody plants in Brazil of importance to Eucalyptus breeding programs when screening for resistance. Furthermore, this is the first report of C. doradensis infecting Eucalyptus and T. granulosa, as well as the first record of C. cubensis infecting T. heteromalla in Brazil.