# Fungi of the _Trichoderma_ Genus: Future Perspectives of Benefits in Sustainable Agriculture
## 3 Occurrence and Abundance of _Trichoderma_ Fungi in Different Environments  
_Trichoderma_ sp. is a genus of filamentous, cosmopolitan fungi commonly found in all soil types and climatic zones [31; 33]. They are considered to be saprophytic organisms capable of colonizing and decomposing dead organic matter [32; 38]. In addition, they exhibit parasitic properties with respect to other fungi, as well as symbiotic and endophytic abilities toward plants [19; 20; 34]. A study by [PERSON] et al. [39] showed that the type of ecosystem influences the species diversity of these microorganisms (Table 1). The above-mentioned authors analyzed the mycological condition of soils occurring in forest ecosystems (coniferous forest and coniferous and broadleaf mixed forest) and steppe (desert steppe and temperate steppe) in the northern Xinjiang region. The results showed that the frequency of isolation of _Trichoderma_ sp. fungi from forest soils was twice as high as that of steppe soils and amounted to 79.26% and 36.55%, respectively. In addition, of the 23 identified species, only _T. asperellum, T. harzianum, T. olobnigsporum, T. paraviridescens, T. rossicum_, and _T. saturnisporum_ were present in all ecosystem types (coniferous forest, coniferous and broadleaf mixed forest, desert steppe, and steppe). [PERSON] et al. [40] compared the species biodiversity of _Trichoderma_ sp. strains obtained from decaying wood in Polish mountain forests. The researchers documented that the highest species diversity was characterized by the Gorce mountain range ([PERSON]'s biodiversity index--1.71), while the lowest was by the Karkonosze Mountains ([PERSON]'s biodiversity index--1.08). _T. atroviride, T. citrinovidre, T. viride_, and _T. viridescens_ were present in all locations, while _T. cremeum, T. koningii_, and _T. longibrachiatum_ were found only in the Gorce range, _T. koningiopsis_ was found only in the Karkonosze Mountains, and _T. gamsii_ and _T. longipile_ were found only in the Tatra Mountains. [PERSON] et al. [41] analyzed the mycological condition of wetlands in South Korea and isolated 18 species of _Trichoderma_ sp. The dominant fungi were _T. aspecellum, T. atroviride, T. atroviride, T. harzianum, T. koningii, T. koningiopsis, T. velutinum_, and _T. virens_. [PERSON] et al. [42] recorded 93 isolates of _Trichoderma_ sp. from the roots of tropical plants in northern Borneo. Among them, the most frequent microorganisms were _T. aspecelloides, T. aspecellum, T. harzianum_, and _T. virens_. In contrast, [PERSON] et al. [43] compared the species biodiversity of _Trichoderma_ sp. isolated from nine sites in India. The above-mentioned authors observed the presence of _T. album, T. amazonicum, T. aspecellum, T. atroviride, T. atroviride,  
Figure 1: Growth of the mycelium of _Trichoderma aspecellum_ T3.1a strain (author’s own scheme). T. caribbaeum, T. erinaceum, T. gamisi, T. hamatum, T. harzianum, T. inhamatum, T. koningiopsis, T. longibrachiatum, T. volisporum, T. petersen, T. pililiferum, T. spirale, and T. tomentosum. Teleomorphs were also classified as Hypocrea intricate, H. nigricians, H. rufa, and H. virens. [PERSON] et al. [44] documented T. afroharzianum, T. atrobrunneum, and T. longibrachiatum from African soils for the first time (Algeria). Many years of studies have shown that Trichoderma fungi can be isolated from non-anthropogenic natural habitats and cultivated soils. According to [PERSON] et al. [45], the type of crop is another factor influencing the species diversity of the soil microbiome (Table 1). The studies of the above authors showed that 8 and 9 species of Trichoderma sp. fungi were isolated from soils under wheat and maize cultivation, respectively, and 14 of them were obtained from rice fields. For wheat, the highest frequencies were _T. harzianum_ (35%), _T. asperellum_ (27%), and _T. virens_ (13%). For maize, the most common microorganisms were _T. asperellum_ (29%), _T. virens_ (21%), and _T. hamatum_ (14%). In rice fields, the dominant species were _T. hamatum_ (25%), _T. harzianum_ (22%), _T.