First report of Ralstonia syzygii subsp. syzygii in Brazil on eucalyptus
Ralstonia syzygii subsp. syzygii was isolated from wilted Eucalyptus urophylla in a commercial nursery in Brazil. Koch’s postulates were confirmed. This is the first record of this pest species (and subspecies) on eucalyptus, and the first record of this pest species (and subspecies) in South America.
Until this publication Ralstonia syzygii subsp. syzygii was only known to occur in Indonesia and its only natural host was clove (Syzygium aromaticum). This report extends its geographical distribution and host range. Ralstonia syzygii is listed on the EPPO A1 List. In some EPPO countries, such as the EU countries, only the two subspecies, Ralstonia syzygii subsp. celebesensis and Ralstonia syzygii subsp. indonesiensis, are listed as quarantine pests.
Sources
Rezende RR, Morgan T, Quintero FO, Santos CC, Oliveira LS, Mafia RG, Rezende GD, Alfenas-Zerbini P (2025) First report of Ralstonia syzygii causing bacteria wilt on eucalyptus in Brazil. Plant Disease (early view). https://doi.org/10.1094/PDIS-10-24-2229-PDN.