Crowded Roots, Stunted Shoots: Growth Under Pressure

Students: Isamar Alcazar Ortiz, Lettcy Covarrubias-Perez, Mia Figueroa Herrera, Grace Kumar, Alysha Lamartine, Italivi Martinez, Jacqueline Salazar Galdamez, Cianna Toscano, Sofia Zuniga, Stacy Solorio Gaspar, Yasmin Romo Macias

Faculty Mentor: Lisa Bentley

Biology

College of Science, Technology, and Business

With our BIOL 131 class, we performed a large greenhouse experiment using three different plant species: radishes, lima beans, and sunflowers. The objective of this experiment was to evaluate the possibility that intraspecific competition is an important ecological force that negatively affects the growth of these three annual plant species. For 10 weeks, we grew radish, lima bean, and sunflower plants at three different densities (low, medium, high) in the Raymond Burr greenhouse. We tended and monitored the experiment throughout the semester. We found that there were significant differences in the height of sunflowers, radishes, and lima bean plants based on density. We also found significant differences in the number of leaves on radish and lima bean plants based on density. The results of this experiment demonstrate that intraspecific competition significantly affects plant growth. As plant density increased, individual plant growth decreased, indicating that competition for limited resources such as light, water, and nutrients intensifies when more individuals of the same species are grown together. This experiment highlights the importance of spacing in plant cultivation and offers insight into population dynamics within plant communities.