Novel species of Celoporthe from Eucalyptus and Syzygium trees in China and Indonesia

Abstract

Many species in the Cryphonectriaceae cause diseases of trees, including those in the genera Eucalyptus and Syzygium. During disease surveys on these trees in southern China, fruiting structures typical of fungi in the Cryphonectriaceae and associated with dying branches and stems were observed. Morphological comparisons suggested that these fungi were distinct from the well known Chrysoporthe deuterocubensis, also found on these trees in China. The aim of this study was to identify these fungi and evaluate their pathogenicity to Eucalyptus clones/species as well as Syzygium cumini. Three morphologically similar fungal isolates collected previously from Indonesia also were included in the study. Isolates were characterized based on comparisons of morphology and DNA sequence data for the partial LSU and ITS nuclear ribosomal DNA, btubulin and TEF-1a gene regions. After glasshouse trials to select virulent isolates field inoculations were undertaken to screen different commercial Eucalyptus clones/species and S. cumini trees for susceptibility to infection. Phylogenetic analyses showed that the Chinese isolates and those from Indonesia reside in a clade close to previously identified South African Celoporthe isolates. Based on morphology and DNA sequence comparisons, four new Celoporthe spp. were identified and they are described as C. syzygii, C. eucalypti, C. guangdongensis and C. indonesiensis. Field inoculations indicated that the three Chinese Celoporthe spp., C. syzygii, C. eucalypti and C. guangdongensis, are pathogenic to all tested Eucalyptus and S. cumini trees. Significant differences in the susceptibility of the inoculated Eucalyptus clones/ species suggest that it will be possible to select diseasetolerant planting stock for forestry operations in the future.

Corticimorbus sinomyrti gen. et sp. nov. (Cryphonectriaceae) pathogenic to native Rhodomyrtus tomentosa (Myrtaceae) in South China

“…In recent years, a number of fungi in the Cryphonectriaceae have been found on Myrtales trees in South China (Chen et al ., , ) and this now includes C. sinomyrti described in the present study. This suggests that there are likely to be additional pathogens in this group that infect both native and non‐native Myrtales trees in South China.…”

“…Morphological differences were observed between the sexual structures produced in nature or in culture, but most features were sufficiently similar to provide useful additional information for the descriptions. This is also consistent with a previous study where artificially induced structures were used to distinguish between different fungal species in Cryphonectriaceae (Chen et al ., ). Based on the naturally occurring and induced fruiting structures, the fungus collected from R. tomentosa could be distinguished relatively easily from other genera of Cryphonectriaceae.…”

“…Other than Cryphonectria spp. that occur on native Fagaceae trees in North and Central China, the three genera, Chrysoporthe , Celoporthe and Corticimorbus , have all been found on Myrtaceae in South China and all of these fungi are associated with canker diseases on trees from which they were isolated (Chen et al ., , ). Corticimorbus sinomyrti was isolated from native R. tomentosa trees in two regions/sites in South China and these areas are 700 km apart.…”

“…Cryphonectria parasitica has been isolated from Chinese chestnut (Castanea mollissima) on which it causes a mild canker and die-back disease (Fairchild, 1913;Shear & Stevens, 1913) and Cryphonectria nitschkei is known from cankers on Quercus (Fagaceae) (Teng, 1934;Myburg et al, 2004). Species of Chrysoporthe and Celoporthe are known from trees in the Myrtaceae and these include Chrysoporthe deuterocubensis from Eucalyptus and Syzygium cumini (Chen et al, 2010;Van der Merwe et al, 2010), Celoporthe syzygii from S. cumini, and Celoporthe eucalypti and Celoporthe guangdongensis from species of Eucalyptus (Chen et al, 2011). Inoculation tests have shown that all these species from the Myrtaceae are pathogenic to Eucalyptus and S. cumini (Chen et al, 2010(Chen et al, , 2011.…”

Luteocirrhus shearii gen. sp. nov. (Diaporthales, Cryphonectriaceae) pathogenic to Proteaceae in the South Western Australian Floristic Region

“…Sequences were aligned to those published for fungi in Cryphonectriaceae (Gryzenhout et al . 2009; Begoude et al 2010, Chen et al 2011, Vermeulen et al 2011) in Geneious. The alignments were deposited in TreeBASE SN14068 (www.treebase.org).…”