Fusarium tanahbumbuense N. Maryani, Sand.

Maryani, N., Sandoval-Denis, M., Lombard, L., Crous, P. W. & Kema, G. H. J., 2019, New endemic Fusarium species hitch-hiking with pathogenic Fusarium strains causing Panama disease in small-holder banana plots in Indonesia, Persoonia 43, pp. 48-69 : 63-65

Fusarium tanahbumbuense N. Maryani, Sand. -Den., L. Lom- bard, Kema & Crous, sp. nov.

— MycoBank MB828962

; Fig. 8

Etymology. Name refers to Tanah Bumbu, the region from where this species was collected in Indonesia.

Typus. INDONESIA, Desa Betung, Kecamatan Kusan Hilir, Tanah Bumbu , Kalimantan Selatan (E115°37'477" S 3°50'77"), on infected pseudostem of Musa sp. var. Pisang Hawa (ABB), 20 June 2014, N. Maryani (holotype specimen and culture, InaCC F 965 ,preserved in metabolically inactive state) .

Sporulation abundant from conidiophores borne on aerial mycelium and from sporodochia. Conidiophores on aerial mycelium abundant on PDA, SNA, and CLA, septate, irregularly of verticil- lately branched; conidiogenous cells monophialidic or polyphialidic, subulate or subcylindrical, smooth- and thin-walled, (11–)13–24(–38) × (4–)5–6(–7) µm (av. 19 × 6 µm), formed terminally, singly or in groups of up to three cells on a stipe, or carried singly and laterally on aerial mycelium, collarettes and periclinal thickening inconspicuous or absent; conidia of one type (macroconidia) falcate and multiseptate, apical cells coni- cal to papillate, basal cells indistinct or foot-shaped, 3–5-sep- tate, formed on both mono- and polyphialides, 3-septate conidia, 31–36(–38.5) × 3.5–5(–5.5) µm; 4-septate conidia, (31–)33.5–43.5(–48) × 3.5–5(–5.5) µm; 5-septate conidia, (30–)37–45(–47) × 4–5.5(–6) µm; av. (30–)34.5–44(–48) × (3.5–)4–5.5(–6) µm. Sporodochia formed abundantly on CLA after 7 d, pale orange; conidiophores in sporodochia irregularly and laterally branched; conidiogenous cells monophialidic, doliiform to ampulliform, smooth- and thin-walled, (9.5–)10–13(–15) × (2.5–) 3–4 µm (av. 11.5 × 3.5 µm), collarettes or periclinal thickening inconspicuous or absent; sporodochial conidia falcate, apical cells gently curved, papillate; basal cells slightly curved, foot-shaped, (2–)3–5-septate: 2-septate conidia, 40.5 × 4.5 µm; 3-septate conidia, (25.5–)29–36.5(–41) × 3.5–4.5 µm; 4-septate conidia, (32.5–)34–40(–46) × 3.5–4.5(–5) µm; 5-septate conidia, (36–)37–43.5(–49) × 3.5–4.5(–5) µm; av. (25.5–)32–41.5(–49) × 3.5–5 µm. Chlamydospores not observed.

Culture characteristics — Colony on PDA showing optimal growth at 25 °C with an average growth rate of 1.3–2.2 mm /d. Colony reverse, rosy buff becoming white towards the margins, turning cinnamon to fawn with age and pigmented. Colony surface cottony, rosy buff becoming white towards the margin, turning hazel with age. Aerial mycelium abundant, cottony, with high sporulation and lacking exudates.

Geography & Host — Tanah Bumbu, South Kalimantan, Musa sp. var. Pisang Hawa (ABB).

Pathogenicity — NA.

Notes — Fusarium tanahbumbuense can be distinguished from the fungus illustrated as F. semitectum by Leslie & Sum- merell (2006) and Nelson et al. (1983) by the absence of microconidia and chlamydospores. The polyphialides observed for this species also greatly differed from those that have been observed for F. semitectum which have 3–5 openings ( Nelson et al. 1983).

Figures

Fig. 8 Fusarium tanahbumbuense (ex-type InaCC F965). a. Culture grown on PDA; b–c. sporodochia on carnation leaves; d–g. aerial conidiophores and conidiogenous cells; h–i. aerial conidia; j–l. sporodochial conidiophores and conidiogenous cells; m–o. sporodochial conidia. — Scale bars: b–c = 50 µm; d–o = 10 µm.