Septate Conidiophores Research Articles

Pyrenochaeta dolichi: an example of a confusing species

The coexistence in the same pycnidial conidioma of discrete ampulliform and hyaline conidiogenous cells and integrated conidiogenous cells on filiform, septate conidiophores, is described in Pyrenochaeta dolichi. A new Monodictys-like synanamorph is also reported in this species. Monodictys-like conidia are produced on lateral branches from the vegetative hyphae and germinate through the conidiogenous scar. The taxonomic position of P. dolichi is discussed since there is no suitable place for this fungus in the current systematic schemes for this group of fungi.

A new species of Arthrobotrys from China

Arthrobotrys obovata sp. nov., a hyaline hyphomycete capturing and consuming nematodes on adhesive networks recovered from forest soil, is described. It is characterized by single or branched, erect, hyaline septate conidiophores, with denticle nodes on conidiophores which bear 5–15 obovoid, 1-septate conidia in loose capitate arrangement. The differences between A. obovata , and A. cystosporia, A. perpasta are tabulated and illustrated.

Dactylella formosana, a new nematode-trapping fungus from Taiwan

Dactylella formosana sp. nov., a nematode-trapping fungus from decayed leaves, is described and illustrated. It is characterized by unbranched, erect, hyaline, septate conidiophores, which bear single, apical fusoid to cylindrical, multiseptate, hyaline conidia. This organism traps nematodes by adhesive knobs formed on lateral stalks or on the distal end of conidia. The differences between D. formosana and D. copepodii, D. leptospora, D. multiformis, D. ramiformis are tabulated and briefly discussed.

Spore development in species of Periconia II. P. byssoides and P. igniaria

Conidia of Periconia byssoides are produced either micronematously on branched or unbranched chains from undifferentiated conidiophores, or macronematously on thickened, brown, septate conidiophores. Micronematous production is similar to that reported in P. prolifica , i.e. the basipetal septation of an elongated conidiogenous cell. The conidiogenous cell at the apex of macronematous conidiophores gives rise polyblastically to numerous chains of conidia, each of which develops by a holobastic process from the apex of a conidium or conidiogenous cell. The youngest conidium at the apex of each chain is, however, the first to develop the characteristic verrucose ornamentation, maturation being basipetal within the chain. In Periconia igniaria no large heads of conidia are produced; the conidiogenous cell at the apex of the conidiophore gives rise to a few conidial chains by a holoblastic process, though further back from the apex spores may be produced by the septation of an elongated conidiogenous cell. Conidia at the apex of a chain develop their mature, spiny ornamentation first; ornamentation in both fungi is brought about by a separation of the thin, outer pellicle from the rest of the wall followed by melanin deposition within these excrescences.

Vanterpoolia, a new genus of sporodochial hyphomycetes

Vanterpoolia, a new genus of sporodochial hyphomycetes, is erected for a fungus occurring on necrotic, newly flushed needles of western hemlock (Tsuga heterophylla (Raf.) Sarg.) in coastal British Columbia, Canada. The genus is characterized by triradiate conidia or rodlike, appendaged conidia produced in acropetal chains from simple, septate conidiophores arising from a pseudoparenchymatous stroma. A single species, Vanterpoolia tsugae n.sp., is described.

A NEW NEMATODE‐DESTROYING HYPHOMYCETE OF THE GENUS HARPOSPORIUM

Drechsler, Charles. (USDA, Plant Industry Sta., Beltsville, Md.) A new nematode‐destroying hyphomycete of the genus Harposporium. Amer. Jour. Bot. 50(8): 839–842. Illus. 1963.—A mucedinaceous parasite that destroyed a largish nematode in a maize‐meal‐agar plate culture to which had been added some leaf mold from an oak wood in central Maryland is newly described as Harposporium dicorymbum. It permeates the host animal with colorless septate assimilative hyphae, 2.5‐8.5 μ wide, that soon put forth procumbent septate conidiophores bearing mostly subglobose phialides with 1‐3 sterigmata. Its very distinctive conidia are composed of a minutely pedicellate globose part, 4‐7 μ in diameter, together with a cylindrical outgrowth, 3‐9 μ long and 2‐3 μ wide, which is furnished distally with a short posterior and a longer anterior beak.

Tuberculous verrucose endocarditis: DAVIE, T. B. Journ. Path. and Bact., 1936, 43, 313

Conidia of Periconia byssoides are produced either micronematously on branched or unbranched chains from undifferentiated conidiophores, or macronematously on thickened, brown, septate conidiophores. Micronematous production is similar to that reported in P. prolifica, i.e. the basipetal septation of an elongated conidiogenous cell. The conidiogenous cell at the apex of macronematous conidiophores gives rise polyblastically to numerous chains of conidia, each of which develops by a holobastic process from the apex of a conidium or conidiogenous cell. The youngest conidium at the apex of each chain is, however, the first to develop the characteristic verrucose ornamentation, maturation being basipetal within the chain. In Periconia igniaria no large heads of conidia are produced; the conidiogenous cell at the apex of the conidiophore gives rise to a few conidial chains by a holoblastic process, though further back from the apex spores may be produced by the septation of an elongated conidiogenous cell. Conidia at the apex of a chain develop their mature, spiny ornamentation first; ornamentation in both fungi is brought about by a separation of the thin, outer pellicle from the rest of the wall followed by melanin deposition within these excrescences.