Identification of a novel QTL contributing to rust resistance in Eucalyptus

Background The genus Eucalyptus has many species that are well adapted to a wide range of environmental conditions in Brazil. However, in some areas diseases are a limiting factor, among which the Eucalyptus rust caused by Puccinia psidii Winter stands out as a destructive pathogen of the Myrtacea. The growth of plants with high levels of infection is severely compromised and these plants end up being dominated by adjacent plants which ultimately leads to their death. The most efficient method to control the disease is through the use of resistant genotypes. A major effect rust resistance QTL has already been identified [1,2], however a residual variance stays unexplained. In this context, our study aimed to identify genomic regions containing quantitative resistance loci to rust based on segregation data of a S1 progeny from an inter-specific (Eucalyptus grandis x E. urophylla) resistant clone.