Discovery of the Eucalyptus canker pathogen Chrysoporthe cubensis on native Miconia (Melastomataceae) in Colombia

Abstract

Chrysoporthe cubensis is one of the most serious canker pathogens on commercially grown Eucalyptus species in the tropics and subtropics. During recent surveys for native hosts of C. cubensis in Colombia, fungi with fruiting structures similar to those of C. cubensis were found on native Miconia theaezans and Miconia rubiginosa, both members of the Melastomataceae. These fungi were identified based on morphology and DNA sequences of the ITS1/ITS2 region of the rDNA operon and the β‐tubulin genes. The majority of isolates from M. theaezans and M. rubiginosa grouped together with South American C. cubensis isolates from Eucalyptus species and Syzygium aromaticum (clove). However, some of the isolates from M. theaezans grouped with isolates of Chrysoporthella hodgesiana, another anamorph species linked to Chrysoporthe, from Tibouchina spp. in Colombia. Pathogenicity of these fungi was assessed on various Melastomataceae. Miconia rubiginosa was more susceptible to infection by C. cubensis than two Eucalyptus clones. Isolates of C. cubensis and Chrysop. hodgesiana were mildly pathogenic on the various hosts included in the pathogenicity trials, and most pathogenic on Tibouchina urvilleana and Tibouchina lepidota.

Taxonomy and pathogenicity of two novel Chrysoporthe species from Eucalyptus grandis and Syzygium guineense in Zambia

“…Following inoculation, Chr. austroafricana from South Africa was shown to be the most pathogenic species (Roux et al 2003;Wingfield 2003;Rodas et al 2005;Gryzenhout et al 2005). Results of the present study have, however, shown that Chr.…”

Species of Mycosphaerellaceae and Teratosphaeriaceae on native Myrtaceae in Uruguay: evidence of fungal host jumps

“…Eucalyptus where these trees are grown as exotics (Coutinho et al 2011;Glen et al 2007;Rodas et al 2005) , there are far fewer examples of movement of apparently introduced Eucalyptus pathogens to native plants (Crous and Groenewald, 2005). Results of this study provide important new information that this movement is far more common than has been previously thought.…”

“…This rust disease is native on Myrtaceae in South and Central America and has adapted to infect Eucalyptus in that region (Coutinho et al 1998, Glen et al 2007). In addition, there are many recent examples of members of the Cryphonectriaceae, that are native on members of the Myrtales, adapted to infect Eucalyptus in Africa (Heath et al 2006) as well as South and Central America and Asia Hodges et al 1986;Myburg et al 2003;Rodas et al 2005). …”

Endophytic Cryphonectriaceae on native Myrtales: Possible origin of Chrysoporthe canker on plantation-grown Eucalyptus

“…However, attempts to isolate these fungi as endophytes by Vermeulen et al (2011) were not successful. This might be explained by the fact that isolations on agar could have been overgrown by more rapidly developing fungi such as for example the Botryosphaeriaceae, which are common endophytes in Angiosperm trees including the Myrtales (Pavlic et al 2007;Roux et al 2000Roux et al , 2001Smith et al 1996b;Slippers and Wingfield 2007 (Gryzenhout et al 2004;Rodas et al 2005;Wingfield et al 2001). Thus, placing branch samples with considerable surface area into moistened florist foam, allowing the samples to dry out slowly over a number of months, stimulated the Cryhonectriaceae present to develop and sporulate.…”

“…Host genera include Lagerstroemia , Miconia (Rodas et al 2005), Psidium (Hodges 1988), Syzygium (Hodges et al 1986), Tibouchina ) and a number of others (Barreto et al 2006;Gryzenhout et al 2006;Seixas et al 2004). In most countries where Eucalyptus species are grown as non-natives, they occur in close proximity to related, native plants in the Myrtales (Seixas et al 2004;Wingfield et al 2001).…”