All
Germination Science Projects
on One Page.
What
makes it possible to put all germination science projects on
single page is their similarity. Plants are complex organisms. They can
be very different as an adult form and have very different lifecycles,
sizes and habitats yet they all start life as a seed. So all you need
for this kind of project is some seeds, water, soil and a bit of
patience.Project Overview.
First of all it's good to do a bit of research on plant seeds.
You probably know that all seeds of flowering plants are divided into 2 major groups: Monocotyledons or monocots and Dicotyledons or Dicots. If you open up the seed you'll see the difference – embryo of monocots have only single leaf while embryo of dicots have 2 embryo leafs. There are many other important differences which we will not discuss here.
Seeds of different species store different amounts of nutrients to feed an embryo. Large seeds with lots of food storage usually found among dicots. Depending on our experiment we may choose to use seeds with plenty of food storage. For example if you'd decided to do simple observational project on the root system development you could choose some bean or avocado seed. You could setup them over the glass of water to observe roots growing. That would allow you to take photos or even make a time-lapse movie of the root growth!
Time required for seed germination is another important variable we want to keep in mind. Some species produce shoots faster then another. Time may vary from one-two days to few weeks! So if you time limited or your experiment requires multiple repetitions you may want to choose fastest seeds of them all.
Good model plants for germination science projects are:
- Soy beans (dicot) germination time 3-4 days.
- Sunflower seeds (dicot)germination time 10-14 days.
- Butter beans (dicot)germination time 6-18 days.
- Corn seeds (monocot)germination time 4-12 days.
At the very first stage of its life seeds are self contained. All they need is a bit of light and water. Within they have all important nutrients to develop. By the way this is the important difference between higher plants and seedless plants like ferns or algae.
However, there much more parameters some of them are subtle that may affect plant germination and even its survival.
Here is the little list of the parameters that you can test in germination science projects:
- Will light affect germination time?
- What about temperature?
- Wetness?
- Amount of oxigen in the atmosphere?
- Amount of carbon dioxide in the atmosphere?
- Bacterial or mold contamination of the soil?
- How deep seed can be planted and still survive?
- How competition affect germination?
- Is competition between different species affect germination?
- Is competition from grown plants affect germination?
- Does magnetic field affect germination rate?
- How pH affect germination?
- Does rooting hormone speed up germination?
- How roothing hormone affect root system development?
Try to add some more questions to this list!
So what exectly happens when you plant seeds in the wet soil?
Plant embryo lives in anabiosis state. In this state all life processes are almost stopped. Cells of embryo do not grow or divide. There is almost no breathing. Embryo spend almost no energy. Time stopped for it. Seed is like a starship with hybernated astronaut flying to some distant star.
Most of the seeds have an internal anti-alarm-clock program that force them spend certain time (few weeks or even months) sleeping until germination process can be turned on. This program is very important – it helps plants to survive hostile seasons.
When time comes usually water and temperature starts germination process. Seed starship arrived to its destination.
Seed coat (outer layer of the seed) becomes transparent for the water. Water fills the embryo cells bringing it back to life, turning on chains of enzyme reactions in the cells and dissolving nutrients in the endosperm, making them available for the embryo.
Seed grows in volume. The root comes out and anchor it in the soil. Then embryo leaf(s) appear and for some time embryo grows feeding mostly on the endosperm. Then root system develops and first real leaves appear.
Materials.
For most of germination
science projects you may need:
- Seeds. You should select them carefully making sure that all of them look good. There should not be obvious damage to the seed coat, signs of mold or inconsistency in coat color. For any germination experiment you'll need at least 2 groups of seeds. One of them will be our test group(s) and another one – control group.
- Plates, jars or petri dishes to soak and sprout the seeds. You may also need a piece of cloth. It's convenient to soak your seeds in water in petri dishes. Some experiments may be completely done in the dishes. The lid is transparent so you can observe results through them. Also it looks very scientific. :)
- Germination tray and potting mix. You can buy one or you can make one.
- Water.
This is basic materials that you will need for most of the experiments. For some experiments you'll need more tools/materials. Check experiment links for specific information.
Basic
Experiment Setup
All germination experiments have fairly similar setup.
- Select and separate seeds in few groups - control group and experimental groups (as many as you need).
- Set up environment conditions for test group and control group(s) in such a way that all conditions are exactly the same except the one that you're testing.
- Observe and measure changes that happens to the seed and record the results.
When experiment is done?
Well, that's up to you to decide and may depend on the experiment goals. In most cases we would suggest experiment complete when 50% of the sprouts in the control group will achieve certain length of root or leafs. Note this condition is only our suggestion, and may depend on the type of the experiment. For example it probably would not be valid if you compare germination of two different species.
