2011 Summer Workshop in Elementary Science s1

2011 Summer Workshop in Elementary Science Planned Laboratory Activities Set-up

June 27 On this day we will at least set up some simple experiments to be observed the following week (July 7, 8).

Making Potting Soil Friable Bagged potting soil contains peat, perlite, vermiculite, sticks, etc. We will break up the potting soil in dishpans, removing larger twigs, etc. We will add water and mix slowly to avoid airborne dust. When the soil is moist enough, it will form a ball on your hand when you squeeze it together. It is dry enough if that ball crumbles at a touch. This combination of moist enough and dry enough is called friable.

Effect of Light and Darkness on Plant Growth 1. Label two cups with your group ID. Label one cup “Light” and the other cup “Dark.” Add a label for the kind of seeds you are using. 2. Fill both cups with friable potting soil to within a centimeter of the rim. 3. Add 12 seeds of radish to each cup 4. Cover the seeds with 2 mm of friable potting soil 5. Place one cup (labeled “Light”) in the designated area for light treatment, and the other cup (labeled “Dark”) in the designated area for dark treatment.

Effect of Water on Plant Growth 1. Label three cups with your group ID. Label one cup “Dry,” one cup “Moderate,” and one cup “Wet.” Add a label for the kind of seeds you are using. 2. Fill all three cups with friable potting soil to within a centimeter of the rim. 3. Add 12 seeds of radish to each cup 4. Cover the seeds with 2 mm of friable potting soil 5. Place the cup labeled “Dry” in the designated area for no watering, the cup labeled “Moderate” in the designated area for moderate watering, and the cup labeled “Wet” in the designated area for soaking. 6. To only the cup labeled “Wet,” add water until the soil is submerged!

Effect of Temperature on Plant Growth 1. Label four cups with your group ID. Label one cup “Cold,” one cup “Room,” one cup “Warm,” and one cup “Hot.” Add a label for the kind of seeds you are using. 2. Fill all four cups with friable potting soil to within a centimeter of the rim. 3. Add 12 seeds of radish to each cup 4. Cover the seeds with 2 mm of friable potting soil 5. Place the cup labeled “Cold” in the refrigerator, the cup labeled “Room” in the designated cabinet in the room, the cup labeled “Warm” in the warm incubator, and the cup labeled “Hot” in the hot incubator.

Effect of Minerals on Plant Growth: Hydroponics 1. Label four cups with your group ID. Label one cup “10X,” one cup “1X,” one cup “0.1X,” and one cup “0X.” Add a label for the kind of seeds you are using. 2. Fill all four cups with white perlite to within 0.5 centimeter of the rim. 3. Pour the corresponding fertilizer solution into each up until the perlite floats up to rim. 4. Add 12 seeds of radish to the perlite in each cup 5. Use a pencil tip or similar object to push each seed down into the perlite, but only so far that it is covered with the bluish fertilizer solution (seed is still visible!) 6. Place the four cups into the designated area for growing on in light. 7. FYI: 10X is 135 grams of 20-20-20 soluble fertilizer dissolved in 1 L of distilled water. “Miracle Grow” would be equivalent to the fertilizer we use. The other concentrations are 1:10 (1 part concentrate mixed in 9 parts of water) serial dilutions of that.

Effect of Light on Seed Germination 1. Line 5 Petri Dishes with a 9cm disc of filter paper. 2. Label the dishes on the bottom with your group ID. Label each dish with a treatment name: “White,” “Red,” “Far-Red,” “Dark,” “Tomato Juice.” 3. For only 4 of your dishes: If your group is working with lettuce, moisten the filter paper with 5 mL of distilled water. If your group is working with peas, moisten the filter paper with 15 mL of distilled water. For the remaining dish labeled “Tomato Juice”: add the same volume of tomato juice instead of water. 4. If your group is working with lettuce, count out 5 groups of 50 lettuce seeds. If your group is working with peas, count out 5 groups of just 10 pea seeds. 5. Add one group of seeds to the moist filter paper in each dish, but save the dish for “Dark” treatment for last. This one has to be wrapped in aluminum foil very quickly (30 seconds or less) after the seeds hit the moist paper! 6. Place the five dishes of seeds into the corresponding area for the proper light or dark treatment. Red goes in red fluorescent light, Far-red goes in far-red incandescent light (along with the dish wrapped in foil to control for temperature), and the White and Tomato Juice treatments in white fluorescent light. 7. Note: this project should have measurable outcomes in just three days, so when this is obvious, Dr. Koning will put all the dishes into the refrigerator until we meet again for observations. Supplies Notes: Perlite and potting soils are available at garden sections of Walmart and HomeDepot. If Petri dishes are not available to you, sandwich- or snack-size ZipLok bags would work as well. The filter paper can be replaced by a single layer of paper towel cut to fit the bag. Radish seeds are available year round in health food stores among their seeds for sprouting. Pea seeds are available year-round at grocery stores in the dry beans section. However, please note that the ones sold there are often “leafless,” having only stipules for photosynthesis and extensive tendrils where leaflets would normally be. Split peas obviously are missing a complete embryo and will NOT work! You need whole seeds. The lettuce seeds we are using are the very photosensitive variety, ‘Tango,’ available from Vesey’s seeds (and few other places). www.veseys.com/us/en/store/vegetables/lettuce/leaflettuce/tangolettuce Most common lettuce seed varieties are less light-sensitive and will give higher germination in the dark (maybe up to 90%!). The bean seeds we used are simply Roman beans from a grocery store in the dry beans section. The Wisconsin Fast Plants (Brassica rapa) we are observing were planted one week ahead of our first meeting. They are a special selection known as ‘Petite’ and are sold by Carolina Biological at a very high price. They go from seed to seed (theoretically) within one month! You will be taking one of the pots home with you and can pollinate the flowers and grow your own seeds from them. When the fruits turn yellow and dry, collect them and crack them open to harvest the small dark seeds inside. Store the seeds in a dry cool place. You may not have refrigerators or incubators in your room, but most schools have places of various temperatures where a light-resistant box of cups could be placed. Shaded windowsills are often cold. Cabinets over radiators or registers are often warm compared to other areas in the room. Some teachers have a small refrigerator they can use in the classroom or in a faculty lounge.