Chapter · January 016 doi: 10. 1515/9783110412789-008 citation reads 46 authors

Taxa

Total ( %)

Pig

Myc

Ascomycota

     Ascomycetous yeast sp. 1 

46 (27 %)

+

M

+

     Ascomycetous yeast sp. 2 

  1 (<1 %)

+

M

–

     Aureobasidium pullulans

31 (18 %)

+

M

+

     Coniozyma leucospermi 

  1 (<1 %)

+

M

+

     Dothichiza sp. 1 

47 (27 %)

+

M

+

     Dothichiza sp. 2 

  1 (<1 %)

+

M

+

     Lecythophora mutabilis 

  3 (2 %)

+

M

–

     Phaeomoniella sp. 

  1 (<1 %)

+

M

+

     Phaeomoniella zymoides 

  1 (<1 %)

+

M

+

     Taphrina wiesneri 

  1 (<1 %)

+

M

+

Basidiomycota

     Cryptococcus adeliensis 

  2 (1 %)

–

–

     Cryptococcus diffluens 

  1 (<1 %)

–

+

     Cryptococcus heveanensis 

20 (12 %)

–

+

     Cryptococcus wieringae 

  1 (<1 %)

–

+

     Rhodotorula colostri 

  4 (2 %)

+

C

–

     Rhodotorula fujisanensis

  9 (5 %)

–

–

     Trichosporon dulcitum 

  1 (<1 %)

–

+

---

132

 

 6 Microbial Pigments

6.4 Pigments and plant endophytes

It is known that fungal melanins can increase fungal survival in some environments (Rizner 

and Wheeler, 2003); however, some endophytic fungi cause  asymptomatic infections in 

aerial tissues of woody plants. The increasing study in this field is desired due to possible 

increased fitness of the plant hosts synthesis and of abundant secondary metabolites, which 

can acquire potential economic significance (Redman et  al., 2002; Schulz et  al., 2002). 

Suryanarayanan et al. (2004) found that melanin in the hyphae of Phyllosticta capitalensis 

(teleomorph Guignardia mangiferae) can be related to the success of this woody tree leave 

endophyte with cosmopolitan (mangroves, dry deciduous forest, moist deciduous forest and 

semi-evergreen forest of temperate and tropical regions) geographic distribution.

Dark septate endophytes colonized plant roots being identified on the basis of commonly 

septate hyphae, usually dark pigmented, with facultatively developed sclerotia (Jumpponen, 

2001). Similarly to Arbuscular mycorrhizal fungi (AMF), DSE may play an important role in 

improving plant performance (Strobel, 2003).

Interestingly, endophytic fungal pigment can surpass the effect of some commercial anti-

biotics against human pathogenic bacteria such as Staphylococcus aureus, Klebsiella pneu-

moniae, Salmonella typhi and Vibrio cholera (Visalakchi and Muthumary, 2010). However, 

most plant species have not been studied for their endophytic root colonization. Some 

studies, as part of mycorrhizal targeted investigations, have revealed the common presence 

of DSE in roots. In a more recent example of target study, Zubek et al. (2011) reported for the 

first time the root colonization of 16 endemic plant species from Asia, belonging to never 

studied Asyneuma, Clementsia, and Eremostachys plant genera. They found that the myce-

lium of DSE complemented the AMF colonization in most studied roots, as it was suggested 

that DSE could enhance plant performance in the case of plants which are rarely or not colo-

nized by AMF (Zubek et al., 2011).

Looking for belowground interactions from a Valdivian Temperate Rainforest in Patago-

nia, Argentina, Fernández et al. (2012) reported the dominant presence of DSE with conspicu-

ous melanized structures in the roots of 21 species of Pteridophytes. It was observed in these 

plants that DSE were growing on the root surface as well as inside it. Within the root, DSE 

formed different types of structures, which sometimes occupied the entire volume of the cell 

(Fig. 6.2). Similar structures have been also reported in high Andean flora (Bruzone, 2008) 

and in different Nothofagus species (Salgado-Salomón et al., 2013; Fernández et al., 2015). 

Melanin is a recalcitrant polymer that provides structural strength and protection from envi-

ronmental stress (Henson et al., 1999), so the occurrence of highly melanised fungal struc-

tures associated with different plant taxa in several environments worldwide emphases the 

importance of this pigment for DSE. It has been also described that these fungi may provide 

important benefits to the host plant, such as protection against pathogens or abiotic stresses 

(water availability, extreme temperatures, frosts), being this capability probably related with 

the high amount of melanin in their mycelia.

---

 

6.4 Pigments and plant endophytes 

 

133

(a)

(b)

(c)

(d)

(e)

(f)

(g)

(h)

(i)

(j)

Fig. 6.2:

 Colonization of Dark Septate Endophytes in pteridophytes of a Valdivian temperate forest.