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

Fig. 6

Type.

China • Jiangxi Province, Yingtan City, Guixi County, Shangqing Town, Longhu Mountain National Forest Park, on diseased leaves of Gardenia jasminoides, 23 June 2022, X. X. Luo (holotype HJAUP M 1729.221; ex-type living culture HJAUP C 1729.221).

Description.

Regular leaf spots, grey white in center, and pale brown at margin with yellowish halo. Asexual morph on PDA: Conidiomata acervular, globose or subglobular, 763–955 μm diam., solitary or aggregated, black. Conidiophores indistinct and reduced to conidiogenous cells. Conidiogenous cells hyaline, smooth, cylindrical to ampulliform. Conidia fusiform, straight or slightly curved, 17.4–25.4 × 5.3–6.7 μm (x ̄ = 21.9 × 6 μm, n = 50), 4 - septate, slightly constricted at the septa; basal cell conical, 3.4–6.4 μm (x ̄ = 5.1 μm), pale brown to subhyaline, smooth, thin-walled, with a single filiform appendage, unbranched, 2.9–4.7 μm (x ̄ = 3.9 μm) long; three median cells doliiform to cylindrical, 11–14.7 μm (x ̄ = 13.2 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, 3.4–5.1 (x ̄ = 4.3 μm) µm long, third cell medium to dark brown, 3.7–5.3 µm (x ̄ = 4.4 μm) long, fourth cell pale to medium brown, 3.7–5.4 µm (x ̄ = 4.5 μm) long; apical cell conical to acute, hyaline, smooth, thin-walled, 2.9–4.3 µm (x ̄ = 3.6 μm) long, with 2–3 (mostly 3) filiform appendages, arising from the apical crest, unbranched, 10–20.6 µm (x ̄ = 14.4 μm) long. Sexual morph not observed.

Culture characteristics.

Colonies on PDA grow fast, filamentous to circular, reaching 70–75 mm diam. after 5 days at 25 ° C in darkness, white, with flocculent aerial 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, 23 June 2022, X. X. Luo. On diseased leaves of Gardenia jasminoides, paratype HJAUP M 1729.222, living culture HJAUP C 1729.222; on diseased leaves of Gardenia jasminoides, paratype HJAUP M 1729.223, living culture HJAUP C 1729.223.

Note.

Three strains (HJAUP C 1729.221, HJAUP C 1729.222 and HJAUP C 1729.223) of Pestalotiopsis gardeniae isolated from leaf spots of Gardenia jasminoides formed a distinct clade sister to P. sichuanensis (SA 3 A 21) with 100 % ML / 1.00 BI bootstrap support (Fig. 1). The ex-type strain HJAUP C 1729.221 is closely related to P. sichuanensis (SA 3 A 21) and comparisons of their nucleotides showed 3 bp differences (1 %, including zero gap) nucleotide differences in three loci. Moreover, P. gardeniae is morphologically distinguished from P. sichuanensis Y. C. Wang, X. C. Wang & Y. J. Yang in its larger conidia (17.4–25.4 × 5.3–6.7 μm vs. 8.6–12.5 × 2.6–3.7 μm) with longer apical filiform appendages (10–20.6 μm vs. 2.6–9.2 μm) (Wang et al. 2019).