Diaporthe bauhiniicola Ning Jiang & Y. Q. Zhu, 2024

Zhu, Yaquan, Ma, Lei, Xue, Han, Li, Yong & Jiang, Ning, 2024, New species of Diaporthe (Diaporthaceae, Diaporthales) from Bauhinia variegata in China, MycoKeys 108, pp. 317-335 : 317-335

Diaporthe bauhiniicola Ning Jiang & Y. Q. Zhu sp. nov.

Fig. 3

Holotype.

China • Guangdong Province, Guangzhou City, Luhu Park , 23 ° 9 ' 11.15 " N, 113 ° 16 ' 46.01 " E, 92 m asl, on diseased leaves of Bauhinia variegata , 8 Aug 2022, Yong Li, Chengbin Wang & Yaquan Zhu, (holotype: CAF 800094 ; ex-type culture: CFCC 58154 ).

Etymology.

Named after the host genus, Bauhinia .

Description.

Conidiomata formed on PDA pycnidial, scattered to aggregated, black, erumpent, raising above surface of culture medium, subglobose, 150–300 μm diam., exuding white or yellowish creamy conidial droplets from central ostioles after 30 days at 25 ° C. Conidiophores reduced to conidiogenous cells. Conidiogenous cells hyaline, unbranched, septate, straight, slightly tapering towards the apex, 6.0–15.0 × 1.5–4.0 μm. Alpha conidia hyaline, aseptate, ellipsoidal to spindle-shaped, biguttulate or with one guttulate, 4.5–7.0 × 2.0–3.0 μm. Beta conidia and gamma conidia not observed. Teleomorph not observed.

Culture characteristics.

Colonies covering entire plate after 2 weeks. On PDA with profuse aerial mycelium, white surface, reverse fulvous. On MEA with fluffy aerial mycelium, dirty white surface, reverse ochreous. On SNA white sparse aerial mycelium, surface and reverse white.

Additional material examined.

China • Guangdong Province, Guangzhou City, Luhu Park , 23 ° 9 ' 11.15 " N, 113 ° 16 ' 46.01 " E, 92 m asl, on diseased leaves of Bauhinia variegata , 8 Aug 2022, Yong Li, Chengbin Wang & Yaquan Zhu, living culture GZ 13 B .

Notes.

Two strains representing Diaporthe bauhiniicola clustered in a clade distinct from its closest phylogenetic neighbour, D. sennae (Fig. 1 ). D. sennae has been reported from the host Senna bicapsularis in China ( Yang et al. 2017). D. bauhiniicola differs from D. sennae by wider alpha conidia (4.5–7.0 × 2.0–3.0 μm in D. bauhiniicola vs. 5.0–6.5 × 1.5–1.8 μm in D. sennae ) ( Yang et al. 2017). Diaporthe bauhiniicola differs from D. sennae in nucleotide sequence data (18 / 529 in ITS, 5 / 490 in cal, 15 / 351 in tef 1, 14 / 677 in tub 2) ( Yang et al. 2017).

Figures

Figure 1. Phylogram of Diaporthe arecae species complex resulting from a maximum likelihood analysis based on a combined matrix of ITS, cal, his 3, tef 1 and tub 2 loci. Numbers above the branches indicate ML bootstrap values (left, ML BS ≥ 50 %) and Bayesian posterior probabilities (right, BPP ≥ 0.9). Isolates from the present study are in bold and ex-type strains are marked with *.

Figure 3. Morphology of Diaporthe bauhiniicola A colonies on PDA, MEA and SNA at 25 ° C after 2 weeks B a diseased leaf of Bauhinia variegata C conidioma formed on PDA after 30 days D conidiogenous cells with attached alpha conidia E – G alpha conidia. Scale bars: 200 µm (C); 10 µm (D – J).