Pleosporales » Pleosporaceae » Gibbago

Gibbago trianthemae

Gibbago trianthemae E.G. Simmons, Mycotaxon 27: 108 (1986)                                                           Fig. 11, 12

Index Fungorum number: IF130298; Facesoffungi number: FoF00522

Saprobic or pathogenic on leaves and leaf stalks of Trianthema portulacastrum (Aizoaceae). Sexual morph: unknown. Asexual morph: Conidiophores 51–94 µm × 3–7 µm (x̅ = 59.6 × 6.1 µm, n = 10), straight or curved, mostly unbranched or rarely branched, pale brown, septate and up to 80 μm in length, solitary or 2–4 loosely fasciculate, erect, simple with an apical conidiogenous locus which proliferates by means of a secondary conidiophore that arises immediately below the apical cell of the existing conidiophore, septate, slightly pigmented. Conidiogenous cells swollen at the apex and hyaline to medium or dark brown, polyblastic, sympodial, 6–8 μm in wide and occasionally 1–5 apical proliferations. Conidia 38–40 µm × 17–19 µm (x̅ = 39.2 × 18.3 µm, n = 10), formed singly at the tip of conidiogenous cell, pale to dark brown with the densely pustular wall, mostly ovoid to oblong, rounded at the base and round to conical at the apex, initially solitary, sometimes becoming catenate, ellipsoid, beakless, pigmented, becoming transversely and longitudinal septate, with apical cells swelling slightly and producing secondary conidia similar to initial ones with distinct constriction at the median septum.

Material examined – NORTH AMERICA, USA, Brazos Co., Texas A. & M. Univ. Expt. Farm, on leaves and leaf stalks of Trianthema portulacastrum (Aizoaceae), 27 August 1967, E.G. Simmons (NY 00945973, isotype).

Economic significance – The fungus in the genus Gibbago is a fungal pathogen or bioherbicide against the weed horse purslane (Trianthema portulacastrum L.) (Akhtar 2013, Gandipilli & Kumar 2018).