Symptoms include red discolouration of young tissue and vascular wilt which leads to shoot and branch dieback (Coutinho et al. 2011; Arriel et al. 2014). Small cankers can develop and are associated with blisters below the young actively growing green bark (Coutinho et al. 2011). Lesions are also present on the leaves and are surrounded by a distinct halo (Coutinho et al. 2011).
The biology and life cycle is poorly understood. In the study by Coutinho et al. (2011) the disease was only observed on young trees (6 months to 2 years). It is suggested that there was a host shift from guava to Eucalyptus (Coutinho et al. 2011). E. psidii can cause death to the tops of trees and hence the tree can form double leaders. The trees also appear to recover rapidly and older trees do not seem to be affected.
Arriel DAA, Fonseca NR, Guimarães LMS, Hermenegildo PS, Mafia RG, et al. 2014. Wilt and die-back of Eucalyptus spp. caused by Erwinia psidii in Brazil. Forest Pathology 44: 255-265.
Coutinho TA, Brady CL, van der Vaart M, Venter SN, Telechea N, et al. 2011. A new shoot and stem disease of Eucalyptus species caused by Erwinia psidii. Australasian Plant Pathology 40: 55-60.
Neto J, Robbs CF, Yamashiro T. 1987. A bacterial disease of guava (Psidium guajava) caused by Erwinia psidii sp. nov. Fitopathologia Brasileira 12: 345-350.
