TheEucalyptuscanker pathogenChrysoporthe cubensisdiscovered in eastern Australia

Abstract

Chrysoporthe cubensis is an important pathogen of commercially planted Eucalyptus species (Myrtaceae) in tropical and subtropical parts of the world where these trees are planted as non-natives. Although the majority of Eucalyptus spp. are native to Australia, Chr. cubensis is not common there and has been reported only once from naturally growing Eucalyptus marginata in Western Australia. Chr. cubensis is able to infect hosts in the Myrtaceae and Melastomataceae other than Eucalyptus, but has not been found on hosts other than Eucalyptus in Australia. Recently, fruiting structures resembling those of Chr. cubensis were discovered on Tibouchina heteromalla, planted as a non-native in the Botanical Gardens in Cairns, northern Queensland. These fruiting structures and resulting isolates were characterised as Chr. cubensis in this study. Pathogenicity studies found that Corymbia spp., including commercially important spotted gum, are susceptible along with E. pilularis and E. dunnii. The discovery of Chr. cubensis on a non-native plant in the northern part of Australia is important as it might imply that the pathogen has been introduced into the country and pose a significant threat to native Eucalyptus forests. Alternatively, this fungus might occur naturally in the area on hosts other than Tibouchina, possibly Eucalyptus or related species, and that Australia forms part of its native range.

Testing the Pathogenic Potential of Cryphonectria parasitica and Related Species on Three Common European Fagaceae

“…The bark pathogen Chrysoporthe cubensis Bruner Gryzenhout causes severe damage on introduced Eucalyptus spp. and native Myrtaceae and Melostomataceae in Southeast Asia, South America, Africa and Australia (Rodas et al, 2005;Nakabonge et al, 2007;Pegg et al, 2010). Therefore, to prevent further biological invasions not only the early detection of potential new invasive plant pathogens is crucial, but also the assessment of its potential host range.…”

Multigene phylogenetic and population differentiation data confirm the existence of a cryptic species within Chrysoporthe cubensis

“…For example, pathogenicity tests on Eucalyptus have been conducted with C. deuterocubensis in Indonesia with results very similar to those for C. cubensis (Wingfield 2003). Pegg et al (2010) have also conducted inoculation trials on Eucalyptus with C. deuterocubensis although the fungus in that study was treated as C. cubensis. Both species also have the ability to infect native woody plants in the Melastomataceae and Myrtaceae and could thus cause serious damage if they were accidentally introduced into new environments with native Myrtaceae or Melastomataceae ).…”

Evaluation of Fungicides as Protective and Curative Treatments against Canker Disease of Eucalyptus urograndis Caused by Chrysoporthe deuterocubensis in Malaysia

“…Despite that Eucalyptus appears to be a promising alternative plantation tree, there were concerns raised regarding their susceptibility and vulnerability against disease threats, ranging from the most common leaf diseases caused by Mychosphaerella and Teratosphaeria species [12][13][14], Ceratocystis wilt disease caused by Ceratocystis species [15,16], Myrtle rust disease [17,18], and stem canker disease caused by Cryphonectriaceae [19][20][21] and Botryosphaericeae [15,22]. Chrysoporthe canker is an infection caused by the genus Crysoporthe Gryzenh.…”

“…Recently, two Chrysoporthe species that have been found to infect Eucalyptus tree plantations worldwide were identified in Malaysia, namely Chrysoporthe deuterocubensis and its sibling species Chrysoporthe cubensis [19,20,23]. The basal cankers caused by C. deuterocubensis can spread several metres up the stem and are lethal to young and juvenile trees [3].…”