Molecular characterization of isolates of bacteria causing apical and dry necrosis in eucalyptus

Eucalyptus are grown in large scale in Brazil, with high productivity and clones providing harvests up to 50m3 a hectare per year. Genetic improvement and forest protection contribute to favorable results of productivity. Currently, bacterial diseases can be a major problem in eucalyptus plantations, occurring in both nursery phases and mature plants. Biochemical and pathogenic tools aid in uncovering the origin of the causal agent. However, molecular characterization allows for identification at the genus and species level, since it performs the amplification of DNA sequences. Full characterization is important for pathogen identification and potential management of diseases. In this study we extracted the DNA from forty-two field and nursery samples with apical necrosis and die-back symptoms, following by PCR with four different primers and finally, sequencing phylogenetic analysis. The results confirm that the damages are caused by the interaction between enterobacteria, specifically Erwinia psidii and Pantoea eucalypti. Furthermore, a smaller-scale interaction with Pseudomonas spp. and Xanthomonas spp. was also observed, acting as opportunistic agents in the plant. Therefore, there is a need to delve deeper into disease control studies, such as utilizing biotechnology approaches. This study highlights the need for using biotechnology to characterize diseases to assist in disease management.