Neofusicoccum luteum (Pennycook & Samuels) Crous, Slippers & A.J.L. Phillips, Stud. Mycol. 55: 248 (2006), Index Fungorum number: IF 500876
Basionym: Fusicoccum luteum Pennycook & Samuels, Mycotaxon 24: 456. 1985.
= Botryosphaeria lutea A.J.L. Phillips, Sydowia 54: 70(2002).
Saprobic or pathogenic on fruits, stems and twigs of woody plants. Sexual morph: Undetermined on Tamarix host (see Phillips et al. 2013 for a description). Asexual morph: Conidiomata 250–310 μm high × 350–525 μm diam. (x = 280 × 431 μm, n = 5), stromatic, solitary to gregarious, immersed, partially erumpent at maturity, dark brown to black, uni- to multi-loculate. Locules 55–225 μm high × 60–170 μm diam. (x = 113 × 102 μm, n = 10), ostiolate. Peridium up to 120 μm wide, composed of several layers of small, heavily pigmented, thick-walled cells of textura angularis, becoming hyaline and smaller towards the conidiogenous region. Conidiophores reduced to conidiogenous cells. Conidiogenous cells 6.8–24.5 × 1.7– 3.6 μm (x = 14.9 × 2.5 μm, n = 25), holoblastic, phialidic, integrated, hyaline, smooth, cylindrical with periclinal thickening. Conidia 16.5–23(−27) × 3.8–6.2(−7.1) μm (x = 20.4 × 5.5 μm, n = 35), hyaline, thin-walled, aseptate, ellipsoidal, widest in the middle or upper third of the conidium, apex subobtuse, base truncate, smooth-walled.
Culture characteristics: Conidia germinating on PDA with in 24 h and germ tubes produced from one or both ends. Colonies fast growing on PDA at 25 °C, covering the medium surface (9 cm Petri-dish) in 5 days, circular, flat, dense, surface white, becoming light iron-grey after 14 days, smooth surface, with entire to slightly undulate edge.
Material examined: ITALY, Province of Ravenna [RA], Lido di Dante, on dead branches of Tamarix sp. (Tamaricaceae), 19 March 2015, Erio Camporesi IT 2421–2 (MFLU 16–0664 and GZAAS), living culture MFLUCC 16–0504, GZCC 15–0050.
Notes: Neofusicoccum luteum has been reported on various woody hosts and is an important plant pathogen (Pennycook and Samuels 1985; Phillips et al. 2002, 2013; Sergeeva et al. 2009). This is the first record of N. luteum on Tamarix species (Phillips et al. 2013). The sexual morph of N. luteum is characterized by uni- or multi-loculate ascostromata, cylindrical, to clavate asci and oval to broadly fusiform, hyaline, aseptate ascospores (Phillips et al. 2013)
FIG Neofusicoccum luteum (MFLU 16–0664) a Appearance of conidiomata on the host b Vertical section through conidioma c, d Conidia developing on conidiogenous cells e Conidia. Scale bars: b = 100 μm, c, e = 20 μm, d = 10 μm