Reproduction in plants can be limited by access to pollen and resources. We previously found that Echinacea plants in the remnants are pollen limited, meaning that if they had access to more pollen, they would produce more seeds. However, the long-term effects of pollen limitation are unknown. Do plants that are super pollen saturated and have high amounts of pollen have a higher lifetime fitness than plants that are pollen limited? Also, we know that the plants in the remnants are pollen limited, but are the plants in the common garden environment also pollen limited? To answer these questions and more, 13 years ago Gretel randomly selected 39 plants from p1; half of these plants were randomly assigned to the pollen addition group, and the others were assigned to pollen exclusion. Every year, plants in the pollen exclusion have their heads bagged and they are not pollinated, while we hand cross every style in the pollen addition group.
In the summer of 2023, six of the original 39 plants were flowering, three from the addition treatment and three from the exclusion treatment. The exclusion treatment plants were covered with exclusion bags to prevent pollination, and the addition plants were hand-pollinated three times throughout the summer.
Start year: 2012
Location: exPt01
Physical specimens: 6 heads harvested from group receiving treatments, and an additional 18 heads harvested from plants in an open, control treatment. Heads are at the Chicago Botanic Garden awaiting processing
Data collected: Plant survival and measurements were recorded as part of our annual surveys in P1 and eventually will be found in the echinaceaLab R package. Data sheets were scanned and entered and can be found here: “~/Dropbox/CGData/115_pollenLimitation/pollenLimitation2023”
You can find more information about the pollen addition and exclusion experiment and links to previous flog posts regarding this experiment at the background page for the experiment.
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