Trichoderma is a genus of fungi that is present in all soils, where they are the most prevalent culturable fungi. Many species in this genus can be characterized as opportunistic avirulent plant symbionts. This refers to the ability of several Trichoderma species to form mutualistic endophytic relationships with several plant species. The genomes of several Trichoderma specieshave been sequenced and are publicly available from the JGI.