103 - Pseudozyma Bandoni emend. Boekhout and a comparison with the yeast state of Ustilago maydis (De Candolle) Corda

Abstract

This chapter focuses on Pseudozyma genus and its member species. The hyphae in this genus occur usually with retraction septa, and the cytoplasm in the cells is separated by lysed cells. Fusiform blastoconidia occur on sterigma-like denticles and may form an aerial mycelium made up of branched, acropetal chains of conidia. Chlamydospores may be present, but ballistoconidia are absent. The colonies are whitish, pinkish, orange, or brownish-yellow, usually dimorphic with the central part yeastlike, and the margin fringed with hyphae. A thin aerial mycelium is usually present, which toward the margin may become zonate. The member species of this genus are Pseudozyma antarctica, Pseudozyma aphidis, Pseudozyma flocculosa, Pseudozyma fusiformata, Pseudozyma prolifica, Pseudozyma rugulosa, Pseudozyma tsukubaënsis, and Ustilago maydis. After undergoing growth on 5% malt extract agar for five days at 17° C, the cells of Pseudozyma antarctica, appear as cylindrical to fusiform, varies in size, with 1–3 oil droplets, and as single. The colonies of this species are dimorphic, withthe center flat to somewhat raised, glabrous to velvety hirsute, smooth to somewhat irregularly furrowed, dull, pale creamish-white to yellowish-brown. The cells of Pseudozyma aphidis, after undergoing growth on 5% malt extract agar for five days at 17° C, appear as fusiform, variable in size, and contain many oil droplets.