Brassica Rapa Lab Report

Francesca Agobe

Section-17

BRASSICA RAPA INTERACTIONS WITH INTRASPECEFIC COMPETITION AMOUNG HIGH AND LOW DENSITY VARIABLE POPULATIONS

Abstract

Competition occurs in plants when there are a limited number of resources. Certain traits that affect advantages or disadvantages in between organisms. Our hypothesis for our experiment that intraspecific competition in low and high density treatments would affect height and survivorship for Brassica rapa. We made high and low density treatments of ten seeds and two seeds respectively. Each treatment had water, soil, and fertilizer. The height and survivorship from each treatment was averaged over four weeks. These results show no significant difference between the high and low treatments. The

Intraspecific competition occurs when the organisms belong to the same species. Competition between different species is known as interspecific competition. An experiment was conducted on Fagus sylvatica L. to determine if competition was occurring in high or low density environments, the findings showed that interspecific and intraspecific competition were comparable (Knoke, et al, 2007)

Brassica rapa is known as a significant model organism because it can reach adulthood in as little as six weeks. It is sometimes referred to as a “fast plant”. (Aspbury & Gabor, 2014). This species is ideal for lab experiments because many different generations can be produced relatively quickly. An experiment conducted by the University of Montana conducted on an experiment with B. rapa dealing with plant competition and found that plant defenses aid plants and plants may naturally select and evolve to compete and defend against competition (Siemens, et al,

rapa our class planted Brassica Rapa seeds at high densities and low densities, the low density, with two seeds, and a high density with ten seeds into pots that were 400 mL. We added a conservative amount of water by sprinkling it, as well as fertilizer and then placed the pots on a rack under 40 watt lights.

After 5 weeks, we harvested the plants and measured height and survivorship. We compared the height and survivorship between the high and low densities using an unpaired T-test in JMP.

Results

The experiment failed to reject the null hypothesis because there was no difference between two groups. The statistical analysis found that there was not a substantial enough difference between the high-density and low-density treatments to support the hypothesis that intraspecific competition would affect height and survivorship (Figures 1 & 2). We found that the low-density and high-density treatments were virtually the same and intraspecific competition did not affect height (t ratio=-2.04, DF=426, p-value= .021). For the survivorship variable, we also found that there was not a noteworthy difference in the results (t-ratio=-5.58, DF=458, p-value Functional Ecology Funct Ecol 29.10 (2015):