Trichoderma shaoguanicum K. Chen & W.Y. Zhuang, 2017

Chen, Kai & Zhuang, Wen-Ying, 2017, Seven soil-inhabiting new species of the genus Trichoderma in the Viride clade, Phytotaxa 312 (1), pp. 28-46 : 39

Trichoderma shaoguanicum K. Chen & W.Y. Zhuang , sp. nov. Fig 6

Fungal Names: FN570280.

Etymology: The specific epithet refers to the type locality.

Diagnosis. Colony growing fast on CMD, PDA and SNA at 25 °C. Conidiophores verticillium-like, phialides subulate, less commonly lageniform or ampulliform, conidia green, ellipsoid.

On CMD after 72 h colony radius 53–55 mm and mycelium covering the plate after 4 d at 25 °C. Colony hyaline, radial, zonate, aerial hyphae common. Conidiation noted after 4 d, formed on aerial hyphae and in pustules, pustules appearing in several concentric zones, denser along the colony margin, loose, first white, turning green after 6 d. Conidiophores verticillium-like, comprising a recognizable main axis, simple side branches arising along the length of the main axis, mostly paired, sometimes solitary. Phialides paired or in whorls of 3, typically straight, subulate, less commonly lageniform or ampulliform, (6.9–)10.3–15.0(–17.2) × 2.8–4.4 μm, l/w (1.8–)3.0–5.6, 2.1–3.3 μm wide at the base (n = 40). Conidia green, with 1–2 larger or many minute guttules, ellipsoid, 4.4–5.3(–7.2) × 3.6–3.9(–4.7) μm, l/ w 1.2 –1.6 (n = 40). No chlamydospores observed. No distinct odor, no diffusing pigment observed.

On PDA after 72 h colony radius 45–48 mm and mycelium covering the plate after 5 d at 25 °C. Colony similar to CMD, but with more pustules, pustules spreading in concentric rings, loose, aggregated. Conidiation noted after 2 d, formed on aerial hyphae and pustules. Chlamydospores common. No distinct odor, no diffusing pigment observed.

On SNA after 72 h colony radius 18–20 mm and mycelium covering the plate after 15 d at 25 °C. Colony hyaline, radial, aerial hyphae inconspicuous, margin not well defined. Conidiation noted after 3 d, formed on pustules, pustules scattered, loose, with irregular shape, first white, turning green after 4 d. Chlamydospores rare. No distinct odor, no diffusing pigment observed.

Strains examined: CHINA. Guangdong: Shaoguan, Chebaling, elev. 500 m, isolated from soil, 9 November 2015, K. Chen TC826 (holotype HMAS 248809, ex-type culture CGMCC 3.18323). ibid., K. Chen TC825 (HMAS 248808).

Notes: According to our phylogenetic analyses ( Fig 1 ), T. shaoguanicum is closely related to T. hamatum which differs in much shorter phialides [(4.0–)5.0–7.7(–10.8) μm long], smaller conidia [(3.5–)4.0–4.7(–5.3) × (2.5–)2.7– 3.0(–3.3) μm], pachybasium-like other than verticillium-like conidiophores, and compact pustules with long hairs protruding from the surface ( Jaklitsch & Voglmayr 2015).

Figures

FIGURE 1. One of the most parsimonious trees based on the analysis of the combined RPB2 and TEF1 matrix, showing phylogenetic positions of the new species. From left to right: MPBP above 50%, MLBP above 70%, and BIPP above 90% are provided at the nodes.

FIGURE 6. Trichoderma shaoguanicum (HMAS 248809). A–C. Cultures at 25 °C (A. CMD, 7 d; B. PDA, 10 d; C. SNA, 7 d); D–E. Conidiation pustules (PDA, 4 d); F–L. Conidiophores and phialides (CMD, 4 d); M–O. Conidia (CMD, 4 d). Scale bars: A–C = 20 mm; D = 400 μm; E = 200 μm; F–G = 20 μm; H–J = 10 μm; K–O = 5 μm.