106 Y. M. Hokama, D. C. Savi, B. Assad et al.
Figure 6. A. Bayesian phylogenetic tree based on ITS sequence, showing the
relationships between Nigrospora species. The tree is rooted with Neurospora crassa
sequence obtained from GenBank. Scale bar shows 2 changes and Bayesian posterior
probability values are indicated at the nodes. B. Bayesian phylogenetic tree based on
LSU sequence, showing the relationships between Nigrospora species. The tree is
rooted with Neurospora terricola sequence obtained from GenBank. Scale bar shows 4
changes and Bayesian posterior probability values are indicated at the nodes.
Nigrospora
In the phylogenetic analysis (Figure 6A and 6B), isolates LGMF1121,
LGMF1133, LGMF1138, and LGMF1156 were found to be closely related to
the species Nigrospora oryzae, whereas isolate LGMF1125 was most closely
related to strain Nigrospora sphaerica (Figure 6 A–B). Strains LGMF1121
and LGMF1133 did not cluster with any type species in this genus; however,
there are few sequences available for this genus (Figure 6). In contrast,
Nigrospora is a genus that has been studied widely because of its secondary
metabolites (Kim et al. 2001; Zhang et al. 2009), and strains in this genus have
been isolated as endophytes from a large number of tropical plant species,
especially medicinal plants (Martinez-Luis et al. 2011).
Colletotrichum
Based on ITS sequence analysis, strains LGMF1135, LGMF1137, and
LGMF1173 were classified as species belonging to the Colletotrichum
gloeosporioides complex. However, as expected, ITS sequences are not
enough to identify the species in this complex (Figure 7). Species of the genus
Colletotrichum are pathogenic (Huang et al. 2009) as well as endophytic in