Evolutionary biologyMushroom's spore size and time of fruiting are strongly related: is moisture important?
Abstract
Most basidiomycete fungi produce annual short-lived sexual fruit bodies from which billions of microscopic spores are spread into the air during a short time period. However, little is known about the selective forces that have resulted in some species fruiting early and others later in the fruiting season. This study of relationships between morphological and ecological characteristics, climate factors and time of fruiting are based upon thorough statistical analyses of 66 520 mapped records from Norway, representing 271 species of autumnal fruiting mushroom species. We found a strong relationship between spore size and time of fruiting; on average, a doubling of spore size (volume) corresponded to 3 days earlier fruiting. Small-spored species dominate in the oceanic parts of Norway, whereas large-spored species are typical of more continental parts. In separate analyses, significant relationships were observed between spore size and climate factors. We hypothesize that these relationships are owing to water balance optimization, driven by water storage in spores as a critical factor for successful germination of primary mycelia in the drier micro-environments found earlier in the fruiting season and/or in continental climates.
References
- 1
Gange A. C., Gange E. G., Sparks T. H.& Boddy L. . 2007Rapid and recent changes in fungal fruiting patterns. Science 316, 71.doi:10.1126/science.1137489 (doi:10.1126/science.1137489). Crossref, PubMed, ISI, Google Scholar - 2
- 3R Development Core Team. 2008R: A language and environment for statistical computing.Vienna, Austria: R Foundation for Statistical Computing. (ISBN 3-900051-07-0, URL) See http://www.R-project.org. Google Scholar
- 4
Pinheiro J. C.& Bates D. M. . 2000Mixed effect models for S and S-plus.New York, NY: Springer. Crossref, Google Scholar - 5
Pinheiro J. C., Bates D., DebRoy S.& Sarkar D. & the R Core team. 2009nlme: linear and nonlinear mixed effects models. R package version 3.1-90. Google Scholar - 6
- 7
Roper M., Pepper R. E., Brenner M. P.& Pringle A. . 2008Explosively launched spores of ascomycete fungi have drag-minimizing shapes. Proc. Natl Acad. Sci. USA 105, 20 583–20 588.doi:10.1073/pnas.0805017105 (doi:10.1073/pnas.0805017105). Crossref, ISI, Google Scholar - 8
Kauserud H., Colman J. E.& Ryvarden L. . 2008Relationship between basidiospore size, shape and life history characteristics: a comparison of polypores. Fungal Ecol. 1, 19–23.doi:10.1016/j.funeco.2007.12.001 (doi:10.1016/j.funeco.2007.12.001). Crossref, ISI, Google Scholar - 9
Meerts P. . 1999The evolution of spore size in agarics: do big mushrooms have big spores?J. Evol. Biol. 12, 161–165.doi:10.1046/j.1420-9101.1999.00020.x (doi:10.1046/j.1420-9101.1999.00020.x). Crossref, ISI, Google Scholar
