## Competition Lab Report Radish & Watermelon

Prepare a report describing your results. Include:

• Figures to summarize your data (showing means and standard deviations)

• If the data allows it, provide statistical tests of your data

• Your report should be structured in a scientific format. It should include

o An introduction section stating the objectives of the experiment

o Hypotheses

o The rational for the study

o Methods, where you describe how you conducted the experiment and explain your experimental design

o Results section, describing your results and any statistical analysis and linked to the figures (Sources of error)

o Discussion of your results providing potential reasons for them and answers to the questions to think about listed below

o References

Competition Data Analysis

For this lab you collected data on plant shoot weight, plant shoot height, and germination/sprouting success for two species of plants growing at two different densities and growing as single cultures or as mixed cultures. The main aim of the lab was to study the effects of intra and inter-specific competition.

You have been provided with the pooled data. During this lab you will conduct some basic analysis on the data, creating tables, graphs and from this analysis you will complete a short group report on your findings.

Measurement Data – Shoot Height & Shoot Weight

Summary tables

You will create summary tables of your data, looking at the means for Shoot Height and Shoot Weight for Radish and Watermelon when grown as single species (intraspecific competition) and as mixed cultures (interspecific competition). Use pivot tables to summarize the data by selecting Pivot Table under the “Insert” tab.

Chart 1 – Shoot Height

You will create one graph, containing the following columns:

Radish-High-Single and Watermelon-High-Single

Radish-High-Mixed and Watermelon-High-Mixed

Radish-Low-S§ingle and Watermelon-Low-Single

Radish-Low-Mixed and Watermelon-Low-Mixed

You will also need to include error bars on your graphs. Plot density/culture on the x axis.

To calculate the error bars, first calculate the Standard Deviation (StDEV), then divide this by the square root (SQRT) of N (your sample size (number of seedlings)

Chart 2 – Shoot Weight

You will create one graph, containing the following columns:

Radish-High-Single and Watermelon-High-Single

Radish-High-Mixed and Watermelon-High-Mixed

Radish-Low-Single and Watermelon-Low-Single

Radish-Low-Mixed and Watermelon-Low-Mixed

You will also need to include error bars on your graphs. Plot density/culture on the x axis.

To calculate the error bars, first calculate the Standard Deviation (StDEV), then divide this by the square root (SQRT) of N (your sample size (number of seedlings)

Standard error = StDEV / (SQRT(n))

Chart 3

You will calculate the mean % sprouting success for each of the treatments and produce a chart with data following the columns as above. The x-axis should be Density/Culture and the Y-axis should be the mean % sprouting success. Remember to include error bars.

Report

Think about what your results are showing you.

• Are the effects of intraspecific competition evident? How about interspecific competition?

• What are some of the sources of error for this lab?

• What is the value of taking multiple parameters for this lab?

• What if we had only measured shoot weight?

Rubric

1. An introduction section stating the objectives of the experiment

2. Hypotheses

3. The rational for the study

4. Materials and Methods (Methods, where you describe how you conducted the experiment and explain your experimental design

5. Results section, describing your results and any statistical analysis and linked to the figures and add (ex. figure 1 ….. under each figure) Sources of error

6. Discussion of your results providing potential reasons for them and answers to the questions to think about listed below

7. References

Methods

1. Obtain 30 planting pots. Paste the tapes and write the number and type of seeds to be planted in each pot.

2. Fill the first pot with soil up to 4.7cm of the pot. Weigh the soil, and records the weight in g.

3. Fill each pot with the same or very similar amount of soil used in the first pot, and do not tamp the soil down, it might prevent the seeds from successfully germinating.

4. Once all pots are marked and contain soil, start planting the seeds. Two different densities of seeds will be planted, 4 seeds per pot, and 40 seeds per pot. The competing treatments are radish seeds grown alone, watermelon seeds grown alone, and radish and watermelon seeds grown together. Each treatment with two different densities will be replicated in five pots. Count the seeds and sprinkle them on the soil in each pot. Make sure that the seeds are spread evenly in the pot. In the two-species pots the seeds of the two types should be interspersed.

5. Cover the seeds with more soil at around 1.5 cm with no tamping.

6. Obtain six trays, then place the pots in the trays according to the competing treatments and the densities.

7. Spray or add each pot with 80mL of water, and make sure that each pot received the same amount of water.

8. Set the trays near a window in the lab, to allow the sunlight reaching the pots

9. Allow the seeds to germinate for 2-3 weeks, and they should be sprayed with water every two days to maintain moisture.

10. The following week measure the height, weight, and number of surviving seedlings.

11. Compare these parameters for the three different treatments and discuss your results.

Paraphrase the methods