Food & Climate 

Read more

Worksheet 2: Weeds, Diseases and pests 

Exercise 1:

You have read about climatic conditions that increase proliferation and prevalence of weeds, diseases, and pests in general.
Find some information about the important pests of your area.

Write to a farmers association and ask for more information and check your local library or the internet in order to get detailed information about these pests.

You can also plan an excursion to a farm or an interview with a farmer.

Interesting aspects can be:

- What are the most important pests?
- What are “good” and “bad” conditions for their proliferation?
- Which crops are affected?
- What kind of damage do they cause?
- How many of these pests are necessary to create severe damage?
- Which kind of countermeasure (chemical and biological) is used?

Exercise 2: Experiment

Observe in an experiment how crops are affected by different levels of pest infestations:

Collect from fields etc. one species of pests e.g. the potato beetle or locusts.

Plant one or two grown plants (e.g. potatos) in a flower pot and put different numbers of potato beetles on it.

Cover it with a mosquito net to prevent the beetles from escaping.

setting of the experiment, picture taken by Florian Schäfer

Possible test arrangements:

Place different numbers of beetles (1 - 5 - 10) in the various pots.

Keep a log and note how the plants are affected over a certain period of time and take pictures.

What are the effects on the plant?
How much damage is done?
How many beetles are tolerable?

What measures should a farmer take?

Author: F. Schäfer, University of Nürnberg / Germany
1. Scientific reviewer:
2. Scientific reviewer:
Educational reviewer: Prof. Schrettenbrunner, Dr. Schleicher, J. Heres
Last update: 07/01/2004