Based on our previous information, we know about the effects of Anubis and Agent Tangerine on the germination of beans. Now, there is a new herbicide being tested for the market called Natron. You are trying to determine the effect of an herbicide called Natron on the sprouting of beans for the Office of Pesticide Programs (OPP) at the Environmental Protection Agency (EPA). This herbicide may be used in the control of weeds on agricultural fields, but concern exists for the runoff and its effect on the germination of wild bean species in the area. We are interested in determining the toxicity of Natron (between 0-2%) on wild mung beans. In other words, we want to know how high a concentration of Natron we can use without significantly impacting the germination rate of beans. Once we know if Natron is toxic to beans and at what concentrations, we can compare those results to Anubis and Agent Tangerine to see which compound is the most toxic to our bean species.
Analyze Data and Interpret Results Collect data:
First, your group will count the number of germinated beans in the Natron exposed (x%) and control groups (0%) and input your data into Table 1, below. If you used more concentrations in your experiment, add additional columns to your table. This is the data you will use in your lab report to report on the results of your experiment (Results section).
Table 1: Number of Beans Sproutingin Herbicide Exposed (x% Natron w/v) and Control Groups . Lab Group. # of Beans Sprouted in Control Group(0%)=. # of Beans Sprouted in Experimental Group( 25%) = . # of Beans Sprouted in Experimental Group( 50%) = . # of Beans Sprouted in Experimental Group( 75%) = . # of Beans Sprouted in Experimental Group( 100%) =
Analyzing Data from Multiple Groups
To improve the significance of an experimental result, replication, the repetition of an experiment on a large group of test subjects, is required. If a treatment is truly effective, the long-term averaging effect of replication will reflect its experimental worth. If it is effective, then the few members of the experimental population who may not have reacted to the treatment will be negated by the large numbers of subjects who were affected by it. Replication reduces variability in experimental results, increasing their significance and the confidence level with which a researcher can draw conclusions about an experimental factor.
In Table 2 below, we provide an example of data collected from exposing multiple groups of 10 beans to Natron. You will use the data from Table 2 to complete the rest of this lab assignment. However, in your lab report, you will only use the results of your own group’s experiment (Recorded in Table 1)
Lab Group # of Beans Germinatedin Control Group (0%) # of Beans Germinated in Experimental Group (.25%) # of Beans Germinated in Experimental Group (.50% # of Beans Germinated in Experimental Group (.75%) # of Beans Germinated in Experimental Group (1.0%)
Group 1 10 9 5 4 0
Group 2 9 9 5 4 0
Group 3 10 10 4 3 0
Group 4 10 9 6 4 0
Group 5 10 10 5 5 0
Group 6 9 10 4 4 0
Total Number germinated 58 57 29 24 0
Table 3: Concentrationof Natron, Number Dead, and Percent Mortalityof Mung Beans Exposed to Natron
Concentration (w/v) Total # Number Dead %Mortality
0 60 2 3%
.25 60 3 5%
.50 60 31 52%
.75 60 36 60%
1 60 60 100%
Overview In this lab, we will cover the basics of scientific writing as it relates to research. Your background document provides an overview of scientific writing and the basic structure of a lab report. Today, you will use the results of your lab groups Natron exposure to beans (Table 1 info from page 1) experiment to write a lab report detailing your research. This is not a group lab assignment. Every person will write their own lab report, in their own words. The sections below will give you a brief description of each component of the lab report. Print and hand in your lab report you may hand it in at your next lab meeting (See Below). Consult the grading rubric on page 7 to make sure you have addressed all of the requirements for your report.
Introduction The introduction establishes the purpose of the report. A well written introduction should answer the questions, why are we doing this research and what do we hope to find out? You also need to include your hypotheses in this section.
Methods The methods section should be a straightforward description of what you did in your experiment. This includes describing the materials you used and how you used them. Based on your methodology section, the reader should be able to replicate your experiment.
Results The results are a summary of your observations. You need to report on all of your results, do not leave anything out. Avoid discussing what your results may mean in this section. That information belongs in the discussion/conclusions section.
Discussion and Conclusions Based on your results, did your outcomes support your original hypothesis? Keep in mind that science never truly proves anything; it contributes to a growing body of evidence about the way our world works. If your research does not appear to support your hypothesis, be truthful about that. Remember that in science we learn as much from failures as we do from successes. You should also address your possible sources of error in your experiment. If you were to repeat this experiment, what would you do differently and why?
Natron Concentration on Bean Germination
In many farmlands today, the use of herbicides is common place and helps maximize yields. Herbicides pose an environmental challenge with regards to the destruction of other plants that were not accounted for during its production. It is therefore important that before an herbicide is rolled out for use en masse, its effects on the surrounding environment be established. This reports aims to determine the effects of a new herbicide called Natron on the germination of the wild mung beans and the concentrations at which its use is detrimental to the wild beans around it.
A total of 60 beans were exposed to different concentrations of Natron and examined for the rates of germination. Beans exposed to 0% concentration of Natron were used as the control for the experiment. The experimental concentrations were 0.25, 0.50, 0.75 and 1%. The total number of dead seeds for each concentration was counted and percentage mortality determined.
60 seeds were planted in all Natron concentrations, at 0% concentration, only 2 (3%) seeds died. At 0.25% Natron cconcentration, 3 (5%) of seeds died. At 0.50% Natron concentration, 31 (52%) seeds died. At 0.75% Natron concentration, 36 (60%) seeds died while at Natron concentration of 1%, all bean seeds died.
From the results, it is evident that Natron has different effects at varying concentrations. As the concentration of Natron in the soil increases, so does the number of seeds killed. The concentration of Natron required for stifling the germination of half the number of wild beans is quiet low (0.50%) while at just 1%, all germinating seeds cease to sprout.
It can thus be concluded from the above results that Natron is toxic to germinating wild bean seeds in lower concentrations. The use of this herbicide can thus be promoted only in very low concentrations to avoid the unintended effects to the environment.