The filamentous fungus Trichoderma asperellum is the genetically distinct agamospecies with cosmopolitan distribution. Together with T. atroviride (teleomorph Hypocrea atroviridis) it belongs to the phylogenetically ancestral section Trichoderma of the mycoparasitic genus Trichoderma (teleomorph Hypocrea, Ascomycota, Dikarya). T. asperellum is frequently isolated from root-free soil, soil litter, rhizosphere of various plants, healthy plant tissues, fungal biomass and dead wood. The broad spectrum of its substrata suggests its outstanding environmental opportunism ranging from saprotrophy to biotrophy. Similar to T. atroviride, T. asperellum is a powerful antagonist of other fungi as it is able to parasitize on them (necrootrophic hyperparasitism or mycoparasitism) or inhibit their growth and development. Therefore this species is utilized as biological control agents against a wide spectrum of plant-pathogenic fungi, fungi-like protozoa such as Phytophthora megakarya and also nematodes. T. asperellum also has been shown to have antibacterial activity through the production of trichotoxin peptaibols. Similar to T. harzianum, T. asperellum is suggested to be a powerful environmental opportunist, which is able to interplay in communities of invasive Trichoderma spp. in various disturbed ecosystems and thus replace or suppress the local mycofauna. Hyphae of T. asperellum may not only grow on plant roots, but also penetrate root epidermis (endophytism), which enhances plant growth and immune system. T. asperellum has been particularly investigated for its ability to stimulate the plants defense reactions against plant pathogens. The genome of T. asperellum will help to understand the evolution of the genus Trichoderma in general and the evolution of Trichoderma mycoparasitism and environmental opportunism and thus help to reveal mechanisms to be used for further domestication of these fungi.
Genome Reference(s)
Druzhinina IS, Chenthamara K, Zhang J, Atanasova L, Yang D, Miao Y, Rahimi MJ, Grujic M, Cai F, Pourmehdi S, Salim KA, Pretzer C, Kopchinskiy AG, Henrissat B, Kuo A, Hundley H, Wang M, Aerts A, Salamov A, Lipzen A, LaButti K, Barry K, Grigoriev IV, Shen Q, Kubicek CP
Massive lateral transfer of genes encoding plant cell wall-degrading enzymes to the mycoparasitic fungus Trichoderma from its plant-associated hosts.
PLoS Genet. 2018 Apr;14(4):e1007322. doi: 10.1371/journal.pgen.1007322