Soredium

Soredia are common reproductive structures of lichens.^[1] Lichens reproduce asexually by employing simple fragmentation and production of soredia and isidia.^[2] Soredia are powdery propagules composed of fungal hyphae wrapped around cyanobacteria or green algae.^[1] These can be either scattered diffusely across the surface of the lichen's thallus, or produced in localized structures called soralia.^[3] Fungal hyphae make up the basic body structure of a lichen.^[2] The soredia are released through openings in the upper cortex of the lichen structure.^[1] After their release, the soredia disperse to establish the lichen in a new location.^[2]

Soredia on Evernia prunastri

References

1. Eichorn, Susan E.; Evert, Ray F.; Raven, Peter H. (2005). Biology of Plants. New York: W.H. Freeman and Company. pp. 289. ISBN 978-1572590410.
2. Cook, Rebecca; McFarland, Kenneth (1995). General Botany 111: Laboratory Manual. Knoxville: University of Tennessee. p. 104.
3. Brodo, Irwin W.; Sharnoff, Sylvia Duran; Sharnoff, Stephen (2001). Lichens of North America. New Haven, Connecticut: Yale University Press. p. 762. ISBN 0-300-08249-5.