Root Assay: I grew Mutants and Col. on Petri dishes with 0μM of Cd. Then I transferred the seeds to 20μM of Cd and 40μM of Cd. After 3 days, I measured their root lengths. Shoot Assay: I recorded the percentage of green color in cotyledon Mutants and Col. For this test I used higher concentrations of Cd; 150μM and 500μM. Cd Accumulation: I grew Arab. mutants and Col. on 0μM of Cd. After 3 days I transferred them to 20μM of Cd mixed with 80ml hydroponic solution and left them there for 5 days until they had accumulated some Cd. I dried the tissue and weighed the plant. I measured the Cd accumulation in their roots/shoots by using the ICP machine.
Root Assay Results: Cd 29 Activation Tagged (Act.Tag.) reached a length of 6mm, which is the longest length for Act.Tag root growth in 40μM of Cd. Cd 16 (EMS) grew 3.7mm, which is the longest root growth for EMS mutants in 40μM of Cd. Shoot Assay Results: Act.Tag. Mutants and the EMS Mutants also had a greater percentage of green shoots in 500μM and 150μM of Cd compared to Col. Cd 29 (Act.Tag.) had 86 percent of its cotyledons green, while the Col only had 26 percent of its cotyledons green. Cd 11 (EMS) had 76 percent of its cotyledons green meanwhile the Col only had 10 percent of its cotyledons green. Cd Accumulation: EMS Graph shows that roots collected more Cd compared to shoots. EMS Mutants reached levels up to 1.7 ppm of Cd in the accumulation process.
The response of Arab. mutants and Col. to cadmium helps us analyze the phenotype of the plants. I found that most of the mutants grew longer roots than the control and had greener shoots. Since the roots have easy access to the Cd, they collected more Cd than the shoots. Since the Mutants have their genes mutated differently some had a different response to Cd. Since there are so many mutants it is important that we continue this experiment and analyze the different phenotypes these mutants in Cd.
The science project attempts to analyze the phenotype of Arabidopsis mutants in Cadmium in terms of their root growth, shoot growth and cadmium accumulation.
Science Fair Project done By Alva S. Monsalvo