||We know that plants use a process called photosynthesis to convert light energy into chemical energy. We also know that plants need sunlight, air, water, and nutrients to grow. In class, we discovered that if one of these qualities is changed, it can affect the growth of the plant. We are interested in learning how a change in a basic necessity for a plant will affect its germination.
||Will the change of pH within the soil affect the soybean's overall outcome in their height?
||If we keep the pH-neutral or slightly lower, then the plant will germinate fastest. According to an article, we saw that soybean seeds typically grow best with pH levels between 6.0-7.5.
||Our experiment will consist a total of 9 different pots with soybean seeds in each. The amount of soil we put into the pot, the amount of soybean seeds we put in each, the amount of water that will be given to each pot, and where the pots will be stored (not sure where yet), will all be our constants for this experiment. We are planning to record how different pH levels effect the plant growth of soybean seeds. The different levels of pH we will be using are 4.0, 6.0, and 8.0 - each level having three trials. We will use the soil acidifier to lower the pH in the 4.0 and 6.0 pH levels, and use the limestone to increase the pH in our 8.0 pH level. Since we are recording plant growth, we will be germinating our seeds first. We took 45 seeds and split them into 8 groups of 5, we then wrapped them in a damp paper towel in a ziploc bag to germinate them for a few days before we transfer them into our pots to start recording actual plant growth. When measuring plant growth, we will be focused on the height, and the way it looks (Does it look wilted or is it healthy and green?)
||The soybeans in soil pH 8 had the highest average of sprouts. In pH 4 the average sprouts were 2.4. In pH 7 the average sprouts were 2.5. in pH 8 the average sprouts were 2.7. It makes sense that the pH of 7 was in the middle since it the middle pH level. In the future we could try mixing different pH levels into the soil, instead of the water.
||High School Students (Grades 9,10,11,12)
||Medford High School