Results + discussion + conclusion
Hello. This is the finale. Thank you for taking your time to watch my journey! Notes will be added where info is reasonable.
Results
Below are the graphs revealing the data presented in the experiment. All data was collected thoroughly each day from March 10 to March 24. The first graph represents the visual data of the germinated spinach seeds. The total spinach seed cumulation however is not satisfactory for calculating statistical significance, because in order to analyze the rate of germination, I need to compare each day’s germination rate for each group. The second graph represents the change in germination (seeds / day) and will be used in the one-way ANOVA calculations.
Note: I had trouble loading the images onto here, so references to graphs are not applicable.
To satisfy the conditions of ANOVA, normality is assumed because the sample of spinach seeds were bought from a large population of Ferry Morse seeds, and the average germination time for spinach seeds is also from a spinach seed population, so it can be assumed that the germination rate for these seeds would follow a large population. Homogeneity of variance is also satisfied because the subjects (spinach seeds) are similar.
Using one-way ANOVA, the calculated F significance test is: F(2,44) = 3.63, p = 0.03. Because the p value (p = 0.03) is greater than the alpha value (⍺ = 0.05), there is a significant difference between the means of the control, single frequency, and soprano group. To find the actual comparison between the groups, a post hoc test needs to be conducted. The Tukey’s HSD (honestly significant difference) is used because the homogeneity of variance test is satisfied. The mean difference for Tukey’s HSD is calculated to 0.31. The resulting mean comparison is: single frequency had a significantly higher germination rate than soprano, single frequency had a significantly higher germination rate than the control, and soprano had a significantly higher germination rate than control.
Discussion
While the hypothesis is refuted for soprano being able to take over single frequency, the results did lead to some interesting finds.
First, many studies support that music, or some form of sound influences a biological response from plants. The spinach plant’s increase in nutrition by some frequencies in PAFT does show similarity to the single frequency group having a significantly higher germination rate than the control. Comparing silence to other studies is not possible because it is impossible to tell whether or not the other literature kept the plants in a quiet environment. The most surprising find of this study is that single frequency exceeded in germination rate than soprano. Unique oscillations possibly are not fully developed in seeds, because they have had no contact with the sun and they are dormant. One study that acknowledges could answer this issue is that there was not enough energy to break the pericarp, so constant bursts of single frequencies would create enough energy to stimulate reactions in the seed [18].
This experiment however is extremely vulnerable to certain variables, mainly equipment. First though, in a statistical setting, it is nearly impossible to assume normality for calculating these results because I did not have multiple trials backing it up, so the statistical approach may need rework in future papers. Having multiple trials as well would solve any inconsistency or errors of variables like having many seeds rotting or inefficient filtering of water. The equipment in this experiment must be done professionally for future research. Equipment that controls certain variables like humidity or water would successfully remove confounding variables. Variations of music should also be included. Even if soprano was found to be the greater in its effect on plants, this effect occurred in one different plant, so it is unlikely that the same style of music can benefit other plants.
Using PAFT technology, which utilizes single frequencies, agricultural farmers can utilize the speakers to its full potential without worrying about certain stages of a spinach’s life cycle. Future research that experiments an entire spinach plant using PAFT can attempt to use bigger fields and measure new variables like distance, to examine cost-effectiveness of a speaker and maintenance.
On the topic of economics, the U.S., being the second most producer, creates about 328,234.41 tonnes on average of the spinach market, while China creates about 16,122,209.67 tonnes on average, which is about a 4912% increase and is the leader of the spinach market [7]. The U.S. however exports 54.8 million pounds more than imports in fresh spinach, with exports at 103.4 million pounds and imports at 48.6 million pounds in 2020 [7]. When exports are more than imports, then the U.S. may consider this produce as limiting domestic dependence on imports and assisting domestic production of spinach [7]. Sound technology could increase the production of spinach when applied large-scale, and more production can be used for economic gain through imports and processing.
Conclusion
Acoustic environments are an interesting way to examine the sound stimulus of plants. Future research can explore not only artificial environments, but also natural environments, like rural road noise or suburban areas, to further distinguish the effects from the variations of sound designs. Allowing other scientific fields like chemical engineering to participate in driving large-scale attribution of sound stimuli would make for a well-rounded, clean solution to growing crops and substituting harmful pesticides and fertilizers. Grown plants are usually explored in studies, but researching the full cycle of a plant will ensure that farmers use less resources to add or remove speakers.
This study aimed to accomplish—1. adding more scientific data to a poorly researched area—and 2. introduce a new way to look at sound called “acoustic environment”. Though music did not perform as well as single frequency, researchers might look to confirming this distinction of single frequency to music. The primary limitation for this experiment was inadequate equipment and one trial. Focusing research on larger-scale farms would incentivize funding for sound studies, and this money can funnel to finally figuring out what specific organelle or protein is induced by sound.
References
[7] – U.S. DEPARTMENT OF AGRICULTURE . (n.d.)Vegatables and Pulses outlooks. https://www.ers.usda.gov/webdocs/outlooks/100102/vgs-365.pdf?v=7917.9
[18] – LIU, Z., FADIJI, T., YANG, J., LI, Z., & TCHUENBOU-MAGAIA, F. (2023). IMPACT OF MECHANICAL STIMULATION ON THE LIFE CYCLE OF HORTICULTURAL PLANT. HORTICULTURAL PLANT JOURNAL, 9(3), 381-394.
Again, thank you for reading my final post, and have a wonderful day!