Curvularia nanningensis Qian Zhang, K.D. Hyde & Yong Wang bis, 2020

Zhang, Qian, Yang, Zai-Fu, Cheng, Wei, Wijayawardene, Nalin N., Hyde 4, Kevin D., Chen, Zhuo & Wang, Yong, 2020, Diseases of Cymbopogon citratus (Poaceae) in China: Curvularia nanningensis sp. nov., MycoKeys 63, pp. 49-67 : 49

Curvularia nanningensis Qian Zhang, K.D. Hyde & Yong Wang bis sp. nov. Figure 3A-I

Diagnosis.

Characterised by the size of conidia.

Type.

China, Guangxi Province, Nanning City, Guangxi Medicinal Botanical Garden, 22°51'N, 108°19'E, on blighted leaves of Cymbopogon citratus , 30 September 2017, Q. Zhang, ZQ0091 (HGUP 11005, holotype, MFLU19-1227, isotype), GUCC 11005 and MFLUCC 19-0092, ex-type.

Description.

Pathogenic on Cymbopogon citratus . Fungus initially producing white to grey lesions with dark borders on all parts of the shoot, later enlarging and coalescing over entire leaf.

Colonies on PDA irregularly circular, with mycelial growth rate = 1.0 cm/day, vegetative hyphae septate, branched, subhyaline to brown, smooth to verruculose, 2-3 µm, anastomosing. Aerial mycelium dense, felted, initially pale grey, becoming darkened and greyish-green at maturity, producing black extracellular pigments. On MEA, the colony morphology similar to PDA, with growth rate = 1.35 cm/day. Sexual morph: Undetermined. Asexual morph: Hyphomycetous. Conidiophores macronematous, arising singly, simple or branched, flexuous, 8-10 septate, geniculate, pale brown to dark brown, paler towards apex, 120-200 × 2-3 µm (av. = 170 × 2.5 µm, n = 30). Conidiogenous cells polytretic, sympodial, terminal, sometimes intercalary, cicatrised, with thickened and darkened conidiogenous loci up to 1.0-1.2 µm diam., smooth. Mature conidia 3 to rarely 4 septa, acropleurogenous, obovoid, usually straight to curved at the slightly wider, smooth-walled, larger third cell from the base, 24.5-36.0 × 14.0-20.5 µm (av. = 29.5 × 17.5 µm, n = 50), sub-hyaline to pale brown end cells, pale brown to dark brown at intermediate cells, with conspicuous or sometimes slightly protuberant hilum. Germination of conidia bipolar.

Distribution.

China, Guangxi Province, Nanning City.

Other material examined.

China, Guangxi Province, Nanning city, Guangxi Medicinal Botanical Garden, on blight leaves of C. citratus , 30 September 2017, Q. Zhang, ZQ0087 (HGUP 11000); ZQ0088 (HGUP 11001); ZQ0089 (HGUP 11002); ZQ0090, (HGUP 11003).

Etymology.

With reference to the location, Nanning City where the fungus was isolated.

Figures

Figure 3. Curvularia nanningensis (GUCC 11005, holotype) A, B diseased symptom C colony on PDA from above D colony on PDA from below E - G conidia and conidiophores H - I conidia. Scale bars: 50 μm (E), 20 μm (F), 10 μm (G - I).