Botryosphaeriales » Aplosporellaceae » Aplosporella

Aplosporella chromolaenae

Aplosporella chromolaenae Mapook & K.D. Hyde, sp. nov. (Fig. 95)

Index Fungorum number: IF557287, Facesoffungi number: FoF 07829; Etymology: Name reflects the host genus Chromolaena, from which this species was isolated.
Holotype: MFLU 20-0298

Saprobic on dead stems of Chromolaena odorata. Sexual morph: Undetermined. Asexual morph: Conidiostromata 360–430 μm long, 685–780 μm wide ( x̄ = 400 × 735 μm, n = 10), superficial, coriaceous, gregarious, dark brown to black. Conidiomata 75–145 μm high × 80–160 μm diam. ( x̄ = 110.5 × 120.5 μm, n = 15), loculate; locules arranged in rows, clustered, gregarious, with 2–3 locules forming groups immersed in conidiostroma, globose to subglobose. Conidiomata wall comprising several layers of thick-walled, dark brown to black cells of textura angularis. Hamathecium comprising 1.5–2.5 μm wide, cylindrical to filiform, septate, branching paraphyses. Conidiophores reduced to conidiogenous cells. Conidiogenous cells 4.5–11 × 2.5–4 μm ( x̄ = 7 × 3.5 μm, n = 5), hyaline, holoblastic, oblong to ampu- liform. Conidia(13–)16–20 × 8.5–12 μm (x̄ = 17.5 × 9.8 μm, n = 25), hyaline when immature, becoming brown to dark brown when mature, aseptate, ellipsoid or oval to reniform, thick-walled, with finely verruculose wall observed clearly in mature conidia.

Culture characteristics: Conidia germinating on MEA within 24 h. at room temperature and germ tubes produced from both ends. Colonies on MEA, filamentous, mycelium slightly raised, moderately fluffy, white aerial hyphae at the surface, spreading from the center with white in reverse (Fig. 97a).

Pre-screening for antimicrobial activity: Aplosporella chromolaenae (MFLUCC 17-1517) showed antimicrobial activity against E. coli with a 9 mm inhibition zone when compared to the positive control (9 mm), but no inhibition of B. subtilis and M. plumbeus.

Material examined: THAILAND, Chiang Rai Province, Doi Pui, on dead stems of Chromolaena odorata, 7 April 2017, A. Mapook (DP108, MFLU 20-0298, holotype); ex- type culture MFLUCC 17-1517.

GenBank numbers: LSU: MT214434, ITS: MT214340, SSU: MT214389

Notes: In a BLASTn search of NCBI GenBank,theclosest match with the ITS sequence of Aplosporella chromolaenae (MFLUCC 17-1517, ex-holotype) with 100% similarity was Aplosporella artocarpi (strain CPC 22791, NR_154688), while the closest match with the LSU sequence with 99.56% similarity was Aplosporella sp. (strain ICMP 17587, EU931110). In the present phylogenetic analysis, A. chromolaenae clustered with A. artocarpi (CPC 22791), with bootstrap support (98% ML, Fig. 94). However, A. chromolaenae differs from A. artocarpi in having smaller conidiomata in conidiostromata (75–145 × 80–160 μm vs. (350– )540–550(–650) × (490–)540–600(–700) μm) and larger conidiogenous cells (3–5 × 2–4 μm vs. 4.5–11 × 2.5–4 μm) (Table 20). Therefore, A. chromolaenae is described as a new species based on phylogeny and morphological comparison.