New Ceratocystis species from Eucalyptus and Cunninghamia in South China

Abstract

During routine surveys for possible fungal pathogens in the rapidly expanding plantations
 of Eucalyptus and Cunninghamia lanceolata in China, numerous isolates of unknown species in the
 genus Ceratocystis (Microascales) were obtained from tree wounds. In this study we identified the
 Ceratocystis isolates from Eucalyptus and Cunninghamia in the GuangDong, GuangXi, FuJian and
 HaiNan Provinces of South China based on morphology and through comparisons of DNA sequence
 data for the ITS, partial β-tubulin and TEF-1α gene regions. Morphological and DNA sequence
 comparisons revealed two previously unknown species residing in the Indo-Pacific Clade. These are
 described here as C. cercfabiensis sp. nov. and C. collisensis sp. nov. Isolates of C. cercfabiensis
 showed intragenomic variation in their ITS sequences and four strains were selected for cloning of
 the ITS gene region. Twelve ITS haplotypes were obtained from 17 clones selected for sequencing,differing in up to seven base positions and representing two separate phylogenetic groups. This is the
 first evidence of multiple ITS types in isolates of Ceratocystis residing in the Indo-Pacific Clade.
 Caution should thus be exercised when using the ITS gene region as a barcoding marker for
 Ceratocystis species in this clade. This study also represents the first record of a species of
 Ceratocystis from Cunninghamia.

This study was initiated through the bilateral agreement between the Governments South
 Africa and China, and we are grateful for the funding via projects 2012DFG31830 (International Science & Technology Cooperation Program of China), 31400546 (National Natural Science Foundation of China: NSFC),2010KJCX015-03 (Forestry Science and Technology Innovation Project of Guangdong Province of China). The Tree Protection and Cooperation Programme (TPCP) and the National ResearchFoundation (NRF), South Africa.

http://link.springer.com/journal/10482

2016-06-30

hb2015