Acremonium capsici S.Q. Tong & Y.J. Wu, 2023

Tong, Shuo-Qiu, Peng, Lei & Wu, Yong-Jun, 2023, Acremonium capsici and A. guizhouense, two new members of Acremonium (Hypocreales, Sordariomycetes) isolated from the rhizosphere soil of Capsicum annuum, MycoKeys 95, pp. 1-13 : 1

Acremonium capsici S.Q. Tong & Y.J. Wu sp. nov.

Fig. 2

Etymology.

Referring to the type strain isolated from the rhizosphere soil of Capsicum annuum .

Type.

Guiyang City , Guizhou Province, China 26°45'75"N, 106°64'87"E, isolated from the rhizosphere soil of Capsicum annuum , August 2022, Shuo-Qiu Tong (dried holotype culture SQT H-01, ex-holotype culture SQT01). GenBank: ITS = OP703286 ; LSU = OP740978 ; SSU = OP750190 ; TEF 1 -α = OP757287 ; RPB2 = OP730522 .

Description.

Culture characteristics (14 days at 25 °C) - Colonies on PDA 20-21 mm diam, white, hairy, flat, radially striated, with a regular edge; reverse white. Colonies on MEA 18-19 mm in diameter, white, floccose, radially striated, with a regular edge; reverse white. Colonies on OA 18-19 mm in diameter, pale white, flat, with regular edge; reverse pale white. Colonies on CMA 18-19 mm in diameter, pale white, felty, with regular edge; reverse pale white. Hyphae hyaline, smooth, septate, branched, 1.0-2.5 µm wide. Phialides straight to flexuous, hyaline, smooth, arising from superficial hyphae, from hyphal strands or from hyphal coils, 20-42 μm (n = 50) long, 1-2 μm (n = 50) wide at the base. Conidia arranged in slimy heads, one-celled, ovoid to ellipsoidal, fusiform, 2.0-3.5 × 1.5-2.0 µm (n = 50), hyaline, smooth, or rough. Chlamydospores and teleomorph were not observed.

Additional specimens examined.

Guiyang City , Guizhou Province, China 26°45'75"N, 106°64'87"E, isolated from the rhizosphere soil of Capsicum annuum , August 2022, Shuo-Qiu Tong, SQT02, ibid., SQT03. GenBank: ITS = OP703287 - OP703288 ; LSU = OP740979 - OP740980 ; SSU = OP750191 - OP750192 ; TEF 1 -α = OP757288 - OP757289 ; RPB2 = OP730523 - OP730524 .

Known distribution.

Guiyang City, Guizhou Province, China.

Notes.

In a phylogenetic tree based on LSU + ITS sequences, Acremonium capsici forms a separate clade sister to A. variecolor in Acremonium sensu lato ( Bionectriaceae ). In a comparison of LSU and ITS nucleotides, A. capsici (Type strain SQT01) has 93% and 83% similarity, in LSU (459/492 bp, one gap) and ITS (388/468 bp, 16 gaps), which is different from A. variecolor (CBS 130360). They are distinguished by the appearance of colonies on OA, MEA, and PDA: colonies of A. capsici grow slowly (less than 25 mm), and are white, while colonies of A. variecolor grow faster (more than 40 mm), and are white to yellowish ( Giraldo et al. 2012). In addition, A. capsici bear simple phialides, while conidiophores of A. variecolor are mostly branched, bearing whorls of two to five phialides ( Giraldo et al. 2012). A. variecolor produces sessile conidia, which is not seen in A. capsici ( Giraldo et al. 2012).

Figures

Figure 2. Morphology of Acremonium capsici sp. nov. a-d colony on PDA, MEA, OA, and CMA after 14 days at 25 ° C (upper surface and lower surface) e phialides f conidia g phialides arising from ropes of hyphae h phialides arising from hyphal coils. Scale bars: 10 μm (e-h).