Pycnidium

A pycnidium (plural pycnidia) is an asexual fruiting body produced by mitosporic fungi, for instance in the order Sphaeropsidales (Deuteromycota, Coelomycetes) or order Pleosporales (Ascomycota, Dothideomycetes). It is often spherical or inversely pearshaped (obpyriform) and its internal cavity is lined with conidiophores. When ripe, an opening generally appears at the top, through which the pycnidiospores escape.^[1]^[2]^[3]

References

^ Punithalingam, E. (1966). "Development of the pycnidium in Septoria". Transactions of the British Mycological Society. 49 (1): 19–25. doi:10.1016/S0007-1536(66)80030-X. ISSN 0007-1536.
^ Roger, C.; Tivoli, B. (1996). "Spatio-temporal development of pycnidia and perithecia and dissemination of spores of Mycosphaerella pinodes on pea (Pisum sativum)". Plant Pathology. 45 (3): 518–528. doi:10.1046/j.1365-3059.1996.d01-139.x. ISSN 0032-0862.
^ Ariyawansa, Hiran A.; Phillips, Alan J.L.; Chuang, Wei-Yu; Tsai, Ichen (2018-07-26). "Tzeananiaceae, a new pleosporalean family associated with Ophiocordyceps macroacicularis fruiting bodies in Taiwan". MycoKeys (37): 1–17. doi:10.3897/mycokeys.37.27265. ISSN 1314-4049. PMC 6072833. PMID 30100794.

Kulik, Martin M. "Symptomless infection, persistence, and production of pycnidia in host and non-host plants by Phomopsis batatae, Phomopsis phaseoli, and Phomopsis sojae, and the taxonomic implications." Mycologia(1984): 274–291.
Calpouzos, L., and D. B. Lapis. "Effects of light on pycnidium formation, sporulation, and tropism by Septoria nodorum." Phytopathology 60.5 (1970): 791–794.