Twenty-two species of postfire ascomycetes belonging to the order Pezizales were screened for biotrophic interactions with roots of lodgepole pine (Pinus contorta Dougl.). Biotrophic associations ranged from pathogenicity to mycorrhizal symbiosis, but most species tested did not show any affinity for roots. Pyropyxis rubra (Peck) Egger and Rhizina undulata Fr. were aggressive pathogens that infected the vascular cylinder and killed the seedlings. Tricharina praecox (Karst.) Dennis var. intermedia Egger, Yang & Korf also had some ability to infect the vascular cylinder, but usually did not kill the seedlings. Geopyxis carbonaria (A. & S.) Sacc. and Trichophaea hemisphaerioides (Mont.) Graddon invaded the cortex, forming complex intracellular structures, but did not penetrate the vascular cylinder. They may form mutualistic associations under certain conditions. The only confirmed mutualistic species was Sphaerosporella brunnea (A. & S.) Svrcek & Kubicka, which formed ectendomycorrhizae. Anthracobia maurilabra (Cooke) Boud. and A. tristis (Bomm., Rouss. & Sacc.) Boud. appear to be primarily root-surface inhabitants with limited capacity to infect cortical tissues through breaks in the epidermis. Gyromitra infula (Schaef.) Quél. penetrated the epidermis but was unable to overcome host defences against pathogenic infection.

EGGER, K. N., and J. W. PADEN. 1986. Pathogenicity of postfire ascomycetes (Pezizales) on seeds and germinants of lodgepole pine. Can. J. Bot. 64: 2368-2371.Forty isolates of postfire ascomycetes (Pezizales) were tested for in vitro pathogenicity on seeds and germinants of lodgepole pine, Pinus contorta Dougl. Two known pathogens, Caloscypha fulgens (Pers.) Boud. and Botrytis cinerea Pers., were included as a check of the method. Caloscyphafulgens was the only fungus that caused serious declines in seed germination, although several species of postfire Pezizales were capable of preemergence seed infection. Rhizina undulata Fr. and Pyropyxis rubra (Peck) Egger were strongly pathogenic on germinants. Pyropyxis rubra was not previously known to be pathogenic. Many isolates were weakly pathogenic on germinants under the conditions tested. EGGER, K. N., et J. W. PADEN. 1986. Pathogenicity of postfire ascomycetes (Pezizales) on seeds and germinants of lodgepole pine. Can. J. Bot. 64: 2368-2371.Les auteurs ont expCriment6 in vitro la pathogCnicitC de quarantes souches d'ascomycktes (PCzizales) venant aprks feu, vis-it-vis les graines et les plantules du Pinus contorta Dougl. Deux pathogknes connus, Caloscyphafulgens (Pers.) Boud. et Botrytis cinerea Pers., ont Ct C inclus pour vCrifier la mtthode. Le C. fulgens est le seul champignon qui a causC une importante diminution dans la germination des graines, bien que plusieurs espkces de PCzizales d'aprks feu se sont avCrCes capables d'infecter les graines avant leur germination. Le Rhizina undulata Fr. et le Pyropyxis rubra (Peck) Egger se sont avCr6s fortement pathogknes pour les plantules. Le P. rubra n'Ctait pas connus jusqu'ici comme pathogkne. Plusieurs souches ont montrC une faible pathogCnicitC sur les plantules dans les conditions expCrimentales utilistes.[Traduit par la revue]

Results of comparative cultural, conidiophore and conidia morphology, growth–temperature, and pathogenicity studies proved that Geniculodendron pyriforme Salt is the imperfect state of Caloscypha fulgens (Pers.) Boudier. The results are discussed in relation to the etiology and ecology of the disease of conifer seeds caused by the fungus.

Molliardiomyces, a new genus of the Hyphomycetes, is described for anamorphic states of some species of the Sarcoscyphaceae (Pezizales, Sarcoscyphineae): Sarcoscypha coccinea, S. occidentalis, Phillipsia domingensis, P. guatemalensis, P. lutea, Pithya cupressina, and Nanoscypha tetraspora. Conidiophores are erect to repent or submerged, monenematous, smooth, hyaline, and irregularly branched or unbranched. Conidia are produced blastically from sympodially proliferating conidiogenous cells. The conidia are smooth, one celled, hyaline or pale yellow, subglobose, ellipsoidal or obovate, with granular contents or containing small oil drops, with bases truncate or rounded, and with or without a frill. Nutritional requirements for production of conidia varied markedly from species to species. Germination of the conidia has not been observed.

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