Chapter Four

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subunit ribosomal DNA (SSU rDNA) to delineate the taxonomic position of the
taxon. Such an approach has proved useful in solving taxonomic confusion in the
ascomycetes, which have few taxonomic distinguishing characters (Mendes-Pereira et
al., 2003). Inderbitzin et al. (2001) also reported one new fungus, Aliquandostipe
khaoyaiensis, from decaying wood in a tropical rain forest, in Khao Yai National
Park.
Chatanon (2001) studied the biodiversity of ascomycetes at Huai-Kha-Khaeng
wildlife sanctuary, and is one of the most relevant works on Thai terrestrial
lignicolous microfungi. Unfortunately this work has not been published in any
journal. Wood, branches, bark and fallen leaves collected during the summer, rainy
and winter seasons were studied for fungi in three forest types (dry evergreen forest,
mix deciduous forest and deciduous dipterocarp forest). Chatanon (2001) observed
that fruiting bodies of ascomycetes were mostly found on bark and hard wood. She
concluded that diversity of fungi in dry evergreen forest was higher than in mix
deciduous forest and deciduous dipterocarp forest, and found highest diversity in the
rainy season. Sixty-seven ascomycetes were reported in this study with 36 lignicolous
species.
Xylariaceous fungi are a group of ascomycetes with great biodiversity and
abundance in tropical Asian forests. They are common on terrestrial wood, as
endophytes in living branches or saprobes in dead branches. These wood decay fungi
develop on dead angiosperms, and can degrade lignin of angiosperm wood and
degrade lignin. This type of decay is called white rot and only a few fungi process
whte rot lignin-degrading enzymes (Eriksson et al., 1990; Eaton and Hale, 1993).
About 60 lignicolous terrestrial microfungi were reported by Thienhirun (1997), in a