Pestalotiopsis eriobotryae X. X. Luo & Jian Ma, 2024

Luo, Xing-Xing, Liao, Ming-Gen, Zhang, Kai, Castañeda-Ruíz, Rafael F., Ma, Jian & Xu, Zhao-Huan, 2024, Morphological and phylogenetic analyses reveal eight novel species of Pestalotiopsis (Sporocadaceae, Amphisphaeriales) from southern China, MycoKeys 109, pp. 207-238 : 207-238

Pestalotiopsis eriobotryae X. X. Luo & Jian Ma sp. nov.

Fig. 5

Type.

China • Jiangxi Province, Yingtan City, Guixi County, Shangqing Town , Longhu Mountain National Forest Park , on diseased leaves of Eriobotrya japonica , 3 November 2022, X. X. Luo (holotype HJAUP M 1742.221 ; ex-type living culture HJAUP C 1742.221 ) .

Etymology.

Referring to the host genus, Eriobotrya from which it was collected.

Description.

Regular leaf spots, grey white in the center with black-spotted acervuli, and dark brown at the margin with rusty halo. Asexual morph on PDA: Conidiomata acervular, globose, 839–2203 μm diam., solitary or aggregated in clusters, black. Conidiophores indistinct and reduced to conidiogenous cells. Conidiogenous cells hyaline, smooth, cylindrical to ampulliform. Conidia fusiform, straight or slightly curved, 18.3–29.2 × 6.5–9 μm (x ̄ = 23.7 × 7.7 μm, n = 50), 4 - septate, slightly constricted at the septa, basal cell conical, 2.8–5.3 μm (x ̄ = 4 μm), pale brown to subhyaline, smooth, thin-walled, with a single filiform appendage, unbranched, 4.1–11.5 μm (x ̄ = 7.1 μm) long; three median cells doliiform to cylindrical, smooth, 12.1–18.6 μm (x ̄ = 15.4 μm), concolorous or sometimes darker at the central cell or the two upper cells, somewhat constricted at the septa, second cell from the base pale brown, 3.4–6.9 µm (x ̄ = 5 μm) long, third cell medium to dark brown, 3.7–6.2 µm (x ̄ = 5.1 μm) long, fourth cell pale to medium brown, 4.4–6.5 µm (x ̄ = 5.4 μm) long; apical cell conical, hyaline, smooth, thin-walled, 3.4–5.3 µm (x ̄ = 4.2 μm) long, with 3–4 (mostly 3) filiform appendages, arising from the apex of the apical cell each at a different point, unbranched, 14.5–29.2 µm (x ̄ = 18.9 μm) long. Sexual morph not observed.

Culture characteristics.

Colonies on PDA grow fast, filamentous to circular, reaching 81–85 mm diam. after 5 days at 25 ° C in darkness, white to buff, with flocculent mycelium and entire edge, forming black conidiomata, and reverse pale orange.

Additional specimen examined.

China • Jiangxi Province, Yingtan City, Guixi County, Shangqing Town, Longhu Mountain National Forest Park , 3 November 2022, X. X. Luo. On diseased leaves of Eriobotrya japonica , paratype HJAUP M 1742.222 , living culture HJAUP C 1742.222 .

Note.

Two strains ( HJAUP C 1742.221 and HJAUP C 1742.222 ) of Pestalotiopsis eriobotryae isolated from leaf spots of Eriobotrya japonica formed a well-supported clade phylogenetically close to P. doitungensis ( MFLUCC 14–0115) with 99 % ML / 0.95 BI bootstrap support (Fig. 1 ). The ex-type strain HJAUP C 1742.221 is closely related to P. doitungensis ( MFLUCC 14–0115) and comparisons of their nucleotides showed 17 bp differences (2 %, including three gaps) nucleotide differences in three loci. Moreover, P. eriobotryae is morphologically distinguished from P. doitungensis X. Y. Ma, K. D. Hyde & J. C. Kang in its wider conidia (6.5–9.0 μm vs. 5.5–6.5 μm) with more and longer apical filiform appendages (3–4 vs. 2–3, 14.5–29.2 µm vs. 4–12 μm) ( Ma et al. 2019).

Figures

Figure 1. Phylogenetic relationship of Pestalotiopsis based on concatenated sequences of ITS, tef 1 - α and tub 2 sequence data. The ML and BI bootstrap support values above 80 % and 0.80 are given above the nodes. Bar = 0.03 substitution per nucleotide position. The tree is rooted to Nonappendiculata quercina (CBS 116061) and N. quercina (CBS 270.82). The strains from the present study are marked in red. Some branches are shortened according to the indicated multipliers to fit the page size, and these are indicated by the symbol (//).

Figure 5. Pestalotiopsis eriobotryae (HJAUP C 1742.221, ex-type) a, b leaf of host plant (front and reverse) c – e conidiomata f, g culture on PDA (front and reverse) h – m conidia n – p immature conidia. Scale bars: 200 µm (d, e); 10 µm (h – p).