I’ve had an amazing semester here in the Echinacea Lab, and today I presented my final update on my internship project. I was able to receive feedback on how to improve both my project and presentation skills. One of the suggestions I received was to add more background to my presentation, so here is some supplemental information to go along with the PowerPoint (attached below). I was working with the P01-nat batch for two consecutive years, 2021 and 2022. I was looking at the plant health indicators of number of basal leaves and length of the longest basal leaf from 2021 because plants receive energy through photosynthesis. My though process was that leaves that are longer and more abundant would lead to a greater ability of an individual plant to photosynthesize and therefore invest more energy in reproduction. I was looking at the reproductive effort and success in the following year, 2022, since Echinacea angustifolia are long-lived perennials. The individual plants that I was working with were originally planted in 1996, so they were pretty well established in the study sites in Minnesota.
I also received feedback on my experimental design, including changing my experimental design a little bit. My current study is phrased as causally linked factors but is more in line with exploring an association between basal leaves and reproductive effort and success rather than a causation. In order to explore more of a causal relationship, one of the suggested studies was to clip leaves so that there was a randomized manipulation on the plants instead of an observational study. Limiting the basal leaves of random plants could allow for a stronger causal relationship to be established between the two factors. A second suggestion to strengthen my current study was to include data from multiple years, since Echinacea angustifolia are long lived and potentially have certain years where reproductive effort spikes over their life cycle and doesn’t spike again, as is one of the potential implications in Sophia’s pollen limitation study.
My hypotheses were not supported by my data, but they still have implications for the further potential future study I mentioned above. The data I collected did not support my hypothesis because the p-values were too high, meaning the data was not statistically significant. I received a suggestion that I should investigate one plant seen in the total achene count graphs (slide 6 of my presentation) that had no basal leaves but produced 200 achenes in the following year. It is possible that this individual only had cauline leaves in 2021, in which case it wouldn’t be relevant to a correlation between basal leaves and reproductive output. Two directions for additional studies that I suggested were the relationship between plant height and reproductive output and overall reproductive fitness as it relates to the number of heads on a plant. The latter question is one that I was going to explore, but I chose to combine the data for my study so that each data point represented the plant as a whole.
I am really grateful to have had the opportunity to be a part of the Echinacea lab this fall. I learned a lot about working in a lab and data analysis using R. I want to give special thanks to Wyatt, Stuart, and Sophia for helping me with R and my project overall, and to all the volunteers and student workers who helped me count, classify, and randomize the 2022 P01-nat data.
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