| Explore | Many factors affect plant growth including soil pH, amount of sunlight, amount of water and almost anything changeable about the surroundings. Genetic traits of plants can be affected by differences in different variables. How do nutrient levels specifically affect genetic traits and why? |
|---|---|
| Research Question | Do the varied levels of nutrients affect the genetic traits of Brassica? |
| Predictions | If the plants are sowed with higher nutrients, then the number of leaves and trichomes will be increased. |
| Experimental Design | Using a 20 oz bottle, cut the top off and flip to fit on the bottom half of the bottle as a funnel. Make a whole in the bottle cap. Feed a 5 inch piece of twine up each whole in the cap. Using layers of Vermiculite (2.5 tbs), 3 (low nutrient) or 12 (high nutrient) Miracle Gro Shake 'n Feed pellets, (2 tbs) 50:50 mixture of Vermiculite and seedling starter mix, then put 6 seeds in each funnel and add (1 tbs) Vermiculite. Then soak the soil mixture in water until water begins to drip from the twine. Fill up the lower part of the bottle until the water reaches the cap. Wrap bottles in foil to prevent algae growth and place in sunlight. We are testing the amount of nutrients put into the early stages of the planting process and seeing how it affects the number of leaves and trichomes. The plants stay in the same temperature, have the same type and amount of soil, and have the same amount of water. |
| Conclusion | This project was intended to research the effect of nutrients on genetic differences in Brassica. Brassica is a commonly used plant in many experiments because it exhibits a plant’s life cycle in a short time span. Researching these genetic differences could lead to purposely changing growing conditions for specific phenotypes. The hypothesis was that the experimental group with more nutrients would have a greater height, number of leaves, and number of trichomes. The procedure was done by fashioning a water reservoir for the Brassica out of a water bottle and planting two groups of Brassica, one with a higher amount of nutrients and one with a lower amount. The plants grew for about 23 days and then they were pollinated using a small paintbrush and a q-tip. The results regarding height showed that the experimental group had a greater height with a mean of 8.6 cm during the middle of their life cycle and 6.8 cm for the control group. Both groups had a mean of 2 leaves. The experimental group had an average number of 1 trichome and the control group had an average of 0. The expected phenotypes of each plant was also recorded to compare to individual and class data. All results seemed to contradict the expected phenotypes with a majority of the plants having one recessive phenotype and one dominant phenotype. The results partly support the hypothesis. The height of the experimental group was found to be greater than the control however there were only minor differences in leaf and trichome numbers. The results mean that an increased amount of nutrients will help nourish the plant through its life cycle. To continue this research, experiments can be conducted with the seeds produced from the plant’s seed pods to see if the increased nutrients has an effect on the plant’s offspring. |
| Investigation Theme | BRASSICA |
| Grade Level | High School Students (Grades 9,10,11,12) |
| Teacher Name | William Bartenslager |
| School Name | Palm Beach Central High School |
| Session | Spring 2022 |