Coneflower Chronicles: Unveiling Echinacea Seed Germination PDF

CONEFLOWER CHRONICLES 1 Coneflower Chronicles: Unveiling the Secrets of Echinacea Seed Germination Student Researcher(s): Samantha Durre and Chloe Henn Chapter: Elgin State: Nebraska Category: Plant Systems. Division:6. CONEFLOWER CHRONICLES Abstract The coneflower, known for its medicinal propertie...

CONEFLOWER CHRONICLES 1 Coneflower Chronicles: Unveiling the Secrets of Echinacea Seed Germination Student Researcher(s): Samantha Durre and Chloe Henn Chapter: Elgin State: Nebraska Category: Plant Systems. Division:6. CONEFLOWER CHRONICLES Abstract The coneflower, known for its medicinal properties, is a staple in many gardens and natural remedies. However, optimizing its growth from seed is crucial for maximizing yields and ensuring plant health but seed germination can be challenging as specific conditions are needed to break dormancy and promote successful seedling emergence. This study aimed to compare the effectiveness of two germination methods, cold stratification and gibberellic acid treatment, in order to identify the most efficient approach for cultivating coneflower seeds. Seeds of wild Echinacea were harvested and stored in dark, temperate conditions 4 months prior to the investigation while two other Echinacea seed varieties were bought at a local garden center. The seeds were subjected to either cold stratification at 4°C for three weeks or gibberellic acid treatment at concentrations of 100 ppm for 48 hours. Germination rates, seedling vigor, and time to germination were assessed for each treatment. Results indicated that both cold stratification and gibberellic acid treatment significantly improved germination compared to untreated control seeds. However, gibberellic acid treatment consistently exhibited higher germination rates and faster seedling emergence compared to cold stratification treatment among all tested. These findings suggest that gibberellic acid is a useful substance for promoting coneflower seed germination. The identification of an effective germination method has implications for both commercial growers and hobbyists seeking to propagate coneflowers efficiently. Utilizing gibberellic acid into germination practices could enhance seedling establishment and contribute to the successful cultivation of coneflower plants for ornamental and medicinal purposes. Further research is warranted to explore optimal conditions and refine germination protocols for different Echinacea species and cultivars. CONEFLOWER CHRONICLES Introduction In this investigation, we aim to elucidate the germination mechanisms of Echinacea spp., commonly known as coneflowers, seeds. In the pursuit of optimizing germination methods for Echinacea seeds, this scientific research study dives into the comparative efficacy of cold scarification, no scarification, and the application of gibberellic acid. Echinacea, known for its medicinal properties and vibrant floral displays, has garnered significant attention in agricultural and horticultural industries. The need for efficient and reliable germination protocols is paramount for both commercial cultivation and conservation efforts. The research is motivated by a clear problem: the variability in germination rates and durations among Echinacea seed varieties that are collected from wild growing plants versus varieties that are store bought. By addressing this issue, the study aims to contribute valuable insights into improving germination practices, potentially enhancing seedling establishment and overall crop yield. Drawing on previous findings, the research builds upon existing knowledge, examining the impact of different scarification methods and gibberellic acid application. The overarching goal is to establish a scientific foundation that can contribute valuable knowledge to the field of plant sciences, with implications for conservation efforts, agricultural practices, and ecological restoration projects. Literature Review Coneflowers belong to the Asteraceae family and are well-known for their daisy-like flowers with prominent, cone-shaped centers. These perennial plants are not only aesthetically pleasing but also play a vital role in supporting pollinators and maintaining biodiversity. The germination process is crucial for the propagation and survival of coneflowers. However, little is known about how germination rates vary among different coneflower varieties. CONEFLOWER CHRONICLES The germination of coneflower seeds has been a subject of interest among botanists and horticulturists due to its medicinal value and popularity in native landscaping. The literature reveals a spectrum of research focused on the germination rates, environmental influences, and the physiological aspects of these species. Studies by Barbara A. Fair (2013) have provided baseline data on the optimal germination temperatures for Echinacea purpurea, indicating a preference for moderate conditions. Contrastingly, research by Richard L. Hassell, Robert J. Dufault, Tyron Phillips, and Teri A. Hale suggests that Echinacea angustifolia may possess a higher germination rate under cooler temperatures, reflecting its adaptation to different ecological niches. The role of soil composition has also been examined highlighting the importance of well-draining soil with adequate organic content to support the initial growth stages of coneflower seedlings. Gibberellic acid (GA3) is a plant hormone that stimulates seed germination by breaking dormancy. This helps with seeds with a tough outer coat, such as coneflowers. When soaked in the acid, it signals the seed to start producing enzymes that break down the endosperm, and provides nutrients for the growing embryo. When plants are treated with this acid, it’s most likely that the plants will have a higher and quicker germination rate. In summary, the germination of Echinacea spp. is a multifaceted process influenced by a range of factors. There is a consensus that species-specific responses to these factors are indicative of their ecological adaptations. However, there remains a need for further research to fully understand the mechanisms at play, particularly in the face of changing global climates. CONEFLOWER CHRONICLES Materials and Methods The hypothesis for this investigation is that the different seed types will germinate at different rates, but the store bought seeds will germinate first and grow faster into a healthier plant and that the gibberellic acid will help expedite this process. Due to other research, the goal of this investigation is to determine which seed germinates first and how long it takes the others to grow into a healthy plant. Echinacea seeds (Echinacea purpurea) were collected from a well-established stand of “wild” purple coneflowers from sandy loam soil in East Central Nebraska and another wellestablished stand of “wild” purple coneflower from loamy soil in East- Central Nebraska. The areas selected to harvest the coneflowers were decided upon to ensure that the seeds came from the same region, but also had genetic diversity. The plants were harvested in September of 2023 before a hard frost set in by digging the entire plant out of the ground and storing it in a dark temperate climate for 1 month. After 1 month, when the plants were dried, seeds of the flowers were carefully removed from the flower, cleaned, sorted and stored in a dry, temperate environment for 2 months before experimentation. Echinacea seeds were also bought from a local, but reputable plant store. After 2 months, 6 seeds from each of the four varieties were exposed to cold scarification by stratifying them in a moist medium at an average temperature of 15 degrees fahrenheit for two weeks, simulating natural winter conditions in Nebraska, U.S.A. The study employed a randomized complete block design, with each treatment (cold scarification, no scarification, and gibberellic acid) assigned randomly to replicate blocks. Each block consisted of a designated tray or container for consistent environmental conditions. A subset of seeds was subjected to cold scarification by stratifying them in a moist medium at 4°C for a specified duration of two weeks, CONEFLOWER CHRONICLES simulating natural winter conditions. Another subset of seeds remained untreated as the control group to assess natural germination rates. A third subset of seeds received treatment with a gibberellic acid solution (GA3) of varying concentrations, applied uniformly to seeds. This was done by mixing the gibberellic acid with 70% isopropyl alcohol. This mixture was then diluted in 1000 milliliters of water. All seed trays were placed in a controlled temperature greenhouse at a constant temperature of 20°C or 68 degrees fahrenheit to simulate optimal growing conditions. Germination rates and times were recorded daily for each treatment. A seed was considered germinated when the radicle emerged, and the cotyledons were visible. Germination percentages were calculated based on the total number of viable seeds. Germination monitoring continued until a sufficient number of seeds germinated in each treatment group, allowing for a comprehensive assessment of germination rates and times. Data collected were subjected to statistical analysis using appropriate software, and the results were interpreted to draw conclusions regarding the effectiveness of cold scarification, no scarification, and gibberellic acid in promoting Echinacea seed germination. This meticulous experimental design and methodology aim to provide reliable insights into the effectiveness of different germination treatments for Echinacea seeds. Results The results of this investigation show that the hypothesis which stated that the store bought plants treated in acid would germinate the quickest was entirely supported. As seen in figure one, the store bought coneflowers that were treated with acid were the first to germinate and had the most growth throughout the time period. Soon after the acid-treated seeds CONEFLOWER CHRONICLES germinated, the store bought seeds that were treated with cold stratification had started to sprout. At about the same time, the control seeds had sprouted. The third type of seed to sprout was the wild seeds treated with acid. On day 17 wild type seeds treated with cold stratification began their germination and the non-treated wild type seeds germinated at day 25. Figure 1. This graph shows the relationship between the seeds and the different types of treatments they had received. On average, coneflower seeds will germinate between 10 and 26 days. Discussion and Conclusions Through a review of the results, it can be concluded that the hypothesis is almost entirely supported. This is due to the results that show that seed germination was expedited through the gibberellic acid treatment. Although the process was faster through the acid treatment, the cold stratification worked as well. It was shown that both methods worked better on the store bought plants and that the wild coneflower seeds had not shown much progress. Gibberellic acid is CONEFLOWER CHRONICLES known to stimulate seed germination through breaking dormancy, which is exactly what it did in the testing. Discussion can be made that show this investigation can support other’s work that show how acid treatments and cold stratification can expedite growth. This research shows that if coneflower seeds are treated with either of these methods, it will speed up the germination process. However, this research doesn’t prove Barbara A. Fair’s (2013) studies state that seeds are better left in moderate conditions. Future research should be made that runs for a longer period of time, different cold stratification methods, and different acid treatments. Continuing to study the growth of wild coneflower seeds will be valuable as we did not have the best results when it came to the wild seeds. This experiment and future ones could help impact the growth of coneflowers, leading to an increase in growth and a better understanding of the impact of treatments on plants. Acknowledgements A couple of significant individuals that we would like to acknowledge for helping us in some way with this investigation are Mr. Andrew Childers and Mrs. Julia Schwartz. Thank you to Andrew Childers, who greatly helped us collect the needed materials to perform our experiment. Mrs. Schwartz, assisted us in the planning process of this research, specifically guiding us on how to research others work that had been done in the field of using cold stratification and gibberellic acid treatment for plant production. We would also like to thank the Elgin FFA Chapter for using the agriscience fair grant money for some of the purchases necessary for this investigation and for the usage of plastics and the FFA greenhouse. CONEFLOWER CHRONICLES References Chuanren D;Bochu W;Wanqian L;Jing C;Jie L;Huan Z; “Effect of Chemical and Physical Factors to Improve the Germination Rate of Echinacea Angustifolia Seeds.” Colloids and Surfaces. B, Biointerfaces, U.S. National Library of Medicine, pubmed.ncbi.nlm.nih.gov/15342019/. Accessed 31 Jan. 2024. Fair, Barbara A. “Evaluation of Species and Cultivars of Coneflower for Southeastern U.S. Landscapes.” Allen Press, 1 Mar. 2013, meridian.allenpress.com/jeh/article/31/1/30/80431/Evaluation-of-Species-and-Cultivars-o f-Coneflower. Accessed 19 Jan. 2024. “Get Over It! Growing Coneflower (Echinacea) from Seed.” Seed Needs LLC, www.seedneeds.com/blogs/flowers/growing-coneflower-from-seed. Accessed 31 Jan. 2024. Hassell, Richard L., Robert J. Dufault, Tyron Phillips, and Teri A. Hale. "Influence of Temperature Gradients on Pale and Purple Coneflower, Feverfew, and Valerian Germination". HortTechnology horttech 14.3 (2004): 368-371. < https://doi.org/10.21273/HORTTECH.14.3.0368>. Web. 19 Jan. 2024. Haynes, Janine O., and Wallace G. Pill. “GIBBERELLIC ACID DURING PRIMING OF PURPLE CONEFLOWER [ECHINACEA PURPUREA (L) MOENCH.] SEEDS IMPROVES GERMINATION AND SEEDLING EMERGENCE.” Hortsci, American Society for Horticultural Science, 1 Apr. 1995, journals.ashs.org/hortsci/view/journals/hortsci/30/2/article-p186c.xml?tab_body=pdf. Accessed 31 Jan. 2024.