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Page number:726 
Remarks (internal):A dried culture to serve as holotype has been deposited at the Plant Protection Research Institute, Pretoria, South Africa (PREM 57302). Ex-holotype culture specimens have been deposited in the culture collection of the South African Medical Research Council, Tygerberg, South Africa (MRC 2802) and the department of Plant Pathology, Kansas State University, Manhattan, Kansas, USA (KSU-X3874). Ex-paratype cultures have been deposited as MRC 8095 (KSU 11783) and MRC 8101 (KSU 11782).
Of the three Fusarium species found associated with mango malformation, two have been described as new in this study. The third group included three isolates (KSU-X4379, KSU-X4381 and KSU-X2330) that were collected from malformed mango tissue in Malaysia. These isolates have sparse aerial mycelium. Their aerial mycelial conidiophores emerge directly from the substrate hyphae (referred to as erect). The polyphialides of these isolates have fewer than 3 conidiogenous openings. Microconidia are borne in false heads and are obovoid in shape, predominantly without septa but with 1-septate conidia occurring occasionally. Macroconidia are short 19.3-24.8-29.5 x 1.3-2.0-3.0 µm and 3-5 septate. Chlamydospores and sterile coiled hyphae are absent (Table II). We believe that this fungus also represents a new taxon, but the collections are insufficient in number to justify a formal description at this stage.
Description type:Original description 
Description:Fusarium sterilihyphosum Britz, Marasas & Wingfield, sp. nov.
Colonies on PDA with average growth rate of 4.8 mm/d at 25 C. Aerial mycelium almost white ('1). Reverse of colonies straw to grayish rose (3''f) and light purple (63i). Conidiophores on aerial mycelium erect, occasionally prostrate. Conidiophores sympodially branched bearing mono- and polyphialides (Fig. 5). Phialides on aerial conidiophores mono- and polyphialidic, up to 30.0 µm long and 3 µm wide. Sterile hyphae present (Fig. 6). Microconidia obovoid, oval to allantoid, 0-septate conidia abundant, 1-septate conidia less common (Fig. 7, 8): 0-septate: 4.5-8.8-14.2 x 1.6-2.6-3.5 µm. Sporodochia seldom present, cream (19'f) to orange (15b). Macroconidia slightly beaked apical cells, a footlike basal cell, 3-5 septate (Fig. 8), 28.4-37.1-47.1 x 2.4-3.2-4.1 µm. Chlamydospores absent.
Etymology. Sterilihyphosum (L. adj) refers to the presence of sterile hyphae in mycelium.
Specimens examined. SOUTH AFRICA. NORTHERN PROVINCE: Tzaneen, Letsitele area, Mango malformation inflorescence on M. indica, 1982, J. M. Darvas MRC 2802 = NRRL 25623 (PREM 57302, HOLOTYPE; KSU-X3874, ex-holotype)
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