Trichoderma

Trichoderma is a very common genus especially in soil and decaying wood. Gliocladium (with strongly convergent phialides) and Verticillium (with straight and moderately divergent phialides) are closely related genera. 

Trichoderma infections in humans have been associated mostly with peritoneal dialysis, organ transplantation, and haematologic disorders (Sandoval-Denis et al. 2014b).

RG-1 organism.

Trichoderma

Phialides and conidia of Trichoderma harzianum.

Morphological description: 
Colonies are fast growing, at first white and downy, later developing yellowish-green to deep green compact tufts, often only in small areas or in concentric ring-like zones on the agar surface. Conidiophores are repeatedly branched, irregularly verticillate, bearing clusters of divergent, often irregularly bent, flask-shaped phialides. Conidia are mostly green, sometimes hyaline, with smooth or rough walls and are formed in slimy conidial heads (gloiospora) clustered at the tips of the phialides.

Key features: 
Hyphomycete with repeatedly branched conidiophores bearing clusters of divergent, flask-shaped phialides.

Molecular identification: 
Species identification is based on multilocus sequence data using ITS, EF-1α, Chi18-5, and actin genes (Sandoval-Denis et al. 2014b).

References: 
Domsch et al. (1980), McGinnis (1980), Rippon (1988), Samson et al. (1995), de Hoog et al. (2000, 2015), Sandoval-Denis et al. (2014b).

Antifungal susceptibility: Trichoderma species limited data (Australian national data); MIC µg/mL.  

  No ≤0.016 0.03 0.06 0.125 0.25 0.5 1 2 4 ≥8
AmB 7           2 4     1
ISAV                     1
VORI 6       1 2 1 2      
POSA 5             4 1    
ITRA 7             5 1   1