Aim: To compare seed pre-treatment techniques to see how different indigenous seeds require different conditions to germinate.

1. Discuss seed biology. Explain the seed structures (cotyledons, seed coat, first leaves, embryonic root) and how the seed is treated to mimic natural germination. The seed coat is damaged or softened similar to the effect that fire would cause. This enables the seed to absorb water. Stress to students that different seeds require different conditions to promote germination.

2. Discuss setting up a fair test where all the factors except the seed treatment are kept the same. This means any differences in results will be due to the treatment received.

3. Prepare seed samples of Blackwood - Acacia melanoxolyn. These can be prepared by the teacher or by the students with care taken using the hot water.

Prepare 10 seeds in each of the following ways:

• microwaved for 30 seconds
• primed in hot water (soaking overnight, absorbs water)
• varied-pre treatment - hot water for a minute, then cold for a minute - doesn't imbibe water but softens the seed coat
• scarified/stratified (seeds that have been rubbed with the sandpaper)
• untreated

4. Fill hyco trays with potting mix.

5. Plant rows of seeds, one row per treatment type. Use the same number of seeds per row. Plant the seed to a depth in the soil equal to the length of the seed. The row of untreated seeds is the comparison or control row, to show it is the treatment that has caused the different germination rates.

6. Label each row as to the type of treatment the seed has received, eg. untreated, scarified.

7. If the school does not have a hot house try and form a partnership with a local nursery. Within the hot house place the trays in the sun to promote growth and keep seeds moist. Ask the nursery staff to keep an eye on the seeds. If there is no hot house available they can be placed in direct sunlight. Take digital photographs as the seeds grow to monitor the progress and assess the treatments. During the three weeks record the results.

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