1. IntraspecificCompetition inViolatricolor Intraspecific Competition in Viola tricolor. B.R. Bird, Undergrad Student, Department of Biology Tennessee Tech University Cookeville, TN, 38505

2. Introduction Problem: stunted growth in garden plants Objective: Find out if intraspecific competition plays a role in growth rate. Hypothesis: Intraspecific competition does affect plant growth rate. Null Hypothesis: Plants are not affected by intraspecific competition.

3. Introduction cont. Two Main Articles Used Article: Effects of Intraspecific Competition and Nutrient Supply on the Endangered Northeastern Bulrush, Scirpus ancistrochaetus Schuyler (Cyperaceae) By: Kendra A. Lentz Foderaro, M. A. 1997. Growth and Survival of Polygonum aviculare L. at a Brine-contaminated site in Southeastern Ohio. The American Midland Naturalist 138: 140-152. Other materials used in this experiment can be found here: Literature CitedLiterature Cited

4. Introduction cont. Lentz and Fonderaro both found that intraspecific competition did affect the plants that they were studying. Intraspecific competition stunted growth rate after it reached

5. Hypothesis Hypothesis: Intraspecifc competition does affect plant growth rate. Null Hypothesis: Plants are not affected by intraspecific competition.

6. Methods Plan: grow pansies in different densities (3,6,10 and 18) and then measure height and weight of each group. After they measurements are taken, the measurements will be compared (mean and t- tests). Expected Results: There will be a significant difference (p-value less than 0.05) between the low density and the high density group.

7. Methods and Material Data will be calculated using a series of t-tests and mean values which will then be plugged into a data form. Methods were modeled after Lentz and Fonderaro studies. T-test example: t-testexample t-test example t-testexample t-test example Dataform Dataform Dataform

8. Results The p-value between the highest density is 0.049 which states that there is a significant difference between the largest density and the small density of pansies. The proves the null hypothesis can be rejected.

9. Results Continued The average stem length peaked and then stabled out.

10. Results Continued The average weight also peaked and then stabled out. The average stem length and average weight table show that the plants reached a capacity cause by nutrient supply and intraspecific competition. Only so much biomass can be supported in a limited area.

11. Discussion and Conclusions My results agreed with Lentz and Fonderaro. Intraspecific competition does affect growth in the plants studied. So either adding nutrients or planting pansies farther apart would increase the size of the individual plants. Literature Cited

12. The End Any Questions? Any Questions?