Journal of Forestry Research (2008) 19(4):277-282
DOI 10.1007/s11676-008-0049-9
First report of an endophyte (Diaporthe phaseolorum var. sojae) from
Kandelia candel
CHENG Zhong-shan
1
, TANG Wen-cheng
1
, XU Shu-lan
1
, SUN Shi-feng
1
, Huang Bo-You
1
, Yan Xi
1
, CHEN Qi-jin*
1
, LIN Yong-cheng
2
1. School of Life Science, Sun Yat-sen University, Guangzhou 510275
2. School of Chemistry and Chemical Engineering, Sun Yat-sen University, Guangzhou 510275
Abstract: Mangrove endophytic fungus 1893 was isolated from Kandelia candel from an estuarine mangrove on the South China Sea Coast.
Two new lactones 1893A and 1893B, together with other known compounds, have been isolated from its fermentation broth. To classify the
endophyte correctly for further industrial application, a combination of morphological and molecular techniques was used to approach its
identity. The endophyte was compared with similar species having trichogynes or trichogyne-like hyphae which apparently fused with an-
theridium-like hyphae, and perithecia initials developing from an ascogonial coil surrounded by enveloping hyphae in early developmental
stages on pure culture. Further morphological characteristics on host and non-host were used for comparison with similar species when the
endophyte was cultivated on leaves of Kandelia candel and Mangifera indica, respectively, which resulted in classifying the endophyte as a
Phomopsis species. The ITS sequence of rDNA was used to infer its phylogenetic relationships with Phomopsis species that resembled the
strain in morphology or ecology. Finally, the endophyte was identified as Diaporthe phaseolorum var. sojae based on morphological and
molecular evidence. Our study is a first report of Diaporthe phaseolorum var. sojae isolated from mangrove Kandelia candel.
Key words: Phomopsis; mangrove endophyte; morphology; phylogeny
Introduction
Mangrove forests are mostly distributed in tropical and subtropi-
cal regions (Gilbert & Mejía-Chang 2002), and several man-
grove species are a valuable source of useful metabolites for
medicinal usage (Kathiresan & Bingham 2001). Some of the
potency of mangrove plants may be due to mutualistic fungal
endophytes associated with host plants (Selosse et al. 2004;
Suryanarayanan et al. 1998). In fact fungi from mangroves are
the second largest group among the marine fungi (Sheadrer et al.
2007). The practical applications of mangrove endophytic fungi
are manifold, as potential bio-control agents, sources of novel
metabolites for therapeutics, plant protection, and other industrial
Foundation item: The search was supported partly by the Guangzhou
Natural Science Foundation (Grant No. 2007Z3-EO581), the Guangdong
Provincial Natural Science Foundation (Grant No.
2007A0200300001-7), the Chinese High-Tech 863 Project (Grant No.
2006AA09Z422), and the National Natural Science Foundation of China
(Grant No. 20572136).
Received: 2008-07-20; Accepted: 2008-08-25
© Northeast Forestry University and Springer-Verlag 2008
The online version is available at http://www.springerlink.com
Biography: CHENG Zhong-shan (1983), male, M.D. College of Life
Science, Sun Yat-sen University, Guangzhou 510275, P. R. China.
E-mail: zhongshan2@yahoo.com.cn The first two authors have the
same contribution.
Corresponding author: CHEN Qi-Jin (email: lsscqj@mail.sysu.edu.cn)
Responsible editor: Chai Ruihai
applications (Wu et al. 2005; Yuan et al. 2005). Our group has
recently undertaken several studies on mangrove endophytic
fungi from South China Sea coast and has isolated various bioac-
tive metabolites (Lin et al. 2001; Zeng et al. 2006).
In the course of our search for novel bioactive compounds
from marine fungi, two new lactones 1893A, 1893B and several
other known compounds (Chen et al. 2003; Chen et al. 2006)
have been isolated from the fermentation broth of the endophytic
fungus No. 1893, which was collected from Kandelia candel in
an estuarine mangrove on the South China Sea Coast. Prelimi-
nary morphological examination revealed that the strain was a
mycelia sterilia. No asci, ascospores or conidia were produced
either on PDA or other artificial media, in 60-d colonies, only
sub-ovoid, light-yellow sclerotia are present, becoming pale
brown as they mature. Therefore, it is not possible to name the
species, which results in hindering the exploration of mangrove
endophytes for industrial application.
Recently, the nucleotide sequences of the internal transcribed
spacer (ITS), large subunit (LSU) nuclear ribosomal DNA,
EF-1α gene and other ribosomal DNA regions as well as RAPD
analysis have been successfully used to determine the phyloge-
netic relationships of species in many diverse genera (Castlebury
et al. 2002; Castlebury et al. 2003; Chi et al. 2007; Farr et al.
2002; Fernández & Hanlin 1996; Promputtha et al. 2007; Schil-
der et al. 2005), especially for Phomopsis species identification,
as old Phomopsis cultures would lost the ability to produce
pycnidia, which is important for providing taxonomically useful
information (Farr et al 1999; Uecker 1989). Thus it would be
necessary to use nucleotide sequences of ribosomal DNA regions
if one want to infer the relationships of mycelia sterialia with
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