Flowers as Islands: Spatial Distribution of Nectar-Inhabiting Microfungi among Plants of Mimulus aurantiacus, a Hummingbird-Pollinated Shrub
- 1.9k Downloads
Microfungi that inhabit floral nectar offer unique opportunities for the study of microbial distribution and the role that dispersal limitation may play in generating distribution patterns. Flowers are well-replicated habitat islands, among which the microbes disperse via pollinators. This metapopulation system allows for investigation of microbial distribution at multiple spatial scales. We examined the distribution of the yeast, Metschnikowia reukaufii, and other fungal species found in the floral nectar of the sticky monkey flower, Mimulus aurantiacus, a hummingbird-pollinated shrub, at a California site. We found that the frequency of nectar-inhabiting microfungi on a given host plant was not significantly correlated with light availability, nectar volume, or the percent cover of M. aurantiacus around the plant, but was significantly correlated with the location of the host plant and loosely correlated with the density of flowers on the plant. These results suggest that dispersal limitation caused by spatially nonrandom foraging by pollinators may be a primary factor driving the observed distribution pattern.
KeywordsFlower Density Floral Nectar Partial Mantel Test Nectar Volume Microbial Distribution
We thank Nona Chiariello and JRBP staff for assistance during field sampling, Chase Mendenhall for his contributions with hummingbird mist-netting, Trevor Hebert for assistance with Fig. S1, and the Biology 44Y students in the spring of 2011 for their assistance in collecting the data presented in Fig. S3. We also thank Bill Gomez, Nathan Kim, Christine Kyauk, Katrina Luna, Pat Seawell, Sebastian Calderon Bentin, and Diamantis Sellis for field and laboratory assistance; Annette Golonka and Carlos Herrera for technical advice; and Paul Ehrlich, Hal Mooney, Karen Nelson, members of the Fukami lab, and several anonymous reviewers for comments. Funding was provided by Stanford University.
- 2.Baas Becking LGM (1934) Geobiologie of inleiding tot de milieukunde. W.P. Van Stockum & Zoon, The HagueGoogle Scholar
- 5.Baker HG, Baker I (1987) The predictability of pollinator type by the chemistry of nectar. Am J Bot 74:645Google Scholar
- 6.Berkeley MJ (1863) The gardeners' chronicle & agricultural gazette, London, UK.Google Scholar
- 10.Cain ML, Bowman WD, Hacker SD (2011) Ecology. Sinauer, SunderlandGoogle Scholar
- 13.Colwell RR (1994) Breeding territories of the male Anna’s hummingbirds at Jasper Ridge Biological Preserve. Biology 96 project, Jasper Ridge Paper, Stanford UniversityGoogle Scholar
- 23.Golonka AM (2002) Nectar-inhabiting microorganisms (NIMs) and the dioecious plant species Silene latifolia.. PhD dissertation, Duke University, Durham, NCGoogle Scholar
- 24.Goslee SC, Urban DL (2007) The ecodist package for dissimilarity-based analysis of ecological data. J Stat Softw 22:1–19Google Scholar
- 38.O’Donnell K (1993) Fusarium and its near relatives. In: Reynolds DR, Taylor JW (eds) The fungal holomorph: mitotic, meiotic and pleomorphic speciation in fungal systematics. CAB International, Wallingford, pp 225–233Google Scholar
- 42.Peay KG, Belisle M, Fukami T (2011) Phylogenetic relatedness predicts priority effects in nectar yeast communities. Proc R Soc B. doi: 10.1098/rspb.2011.1230