so you think you can plant
- Project reviewer
Joined 14 Sep 2018
Project by group gehsbeardsleyfall2018
Info
Explore | We know that plants grow based on the weather and adapt to the environment around them by regulating water intake and energy usage via their stomata and photosynthesis. Through our research we have also found out that abscisic acid plays a vital role in the growth of these plants, and that... |
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Research Question | What effects does the frequency of watering and use of abscisic acid have on the leaves lost and length of stem of our different plants? We came up with this because we know that both water and ABA have effects on the growth of plants. This question fits our topic because we know that abscission... |
Predictions | High water-ABA-wt: Lose substantial leaves, grow moderately High water-no ABA-wt: Lose some leaves, grow substantially High water-ABA-aba1-1: Lose some leaves, grow moderately High water-no ABA-aba1-1: Not lose many leaves, grow substantially High water-ABA-abi1-1: Not lose many leaves, grow... |
Experimental Design | Our plan is to have three bins with three different water levels: high, medium, and low. Each bin has two pods, one with ABA and one without. And each of these pods has two wt, two abi1-1 and two aba1-1. We will water the high water bin to 400mL 3 times a week (Monday, Wednesday, Friday), the... |
Conclusion | What claim can we make from our experiment? What are possible explanations for our results? How do the data we collected and our reasoning with scientific ideas support our claim? What future experiments could be done to expand on the results of this experiment? |
About this Project |
Updates
As this research project is now in the final stages of wrapping-up, we wish to thank everyone who participated in this inquiry; the students, mentors, teachers and others behind the scenes. We appreciate all of your efforts and contributions to this online learning community.
Scientific exploration is a process of discovery that can be fun! There are many unanswered questions about plants just waiting for new scientists to consider, investigate, and share.
We will be archiving groups and projects on December 17, after which time new posts will not be able to be added. Please come back and visit the PlantingScience Project Gallery anytime to view this project in the future. You can search the Gallery by key word, team name, topic, or school name.
Good bye for now.
Warm regards,
The PlantingScience team
Thanks for sending the poster! It looks great. Very professional layout.
On the graphs, are they showing only the change in stem length or number of leaves on each day, not the total? I am only guessing, but otherwise I can't see how the stem length could go up and then back down. Or like in Fig 5, how can you have a stem length of >10 on day 20, but then go back to 0 on day 22?
Thank you! Yes, the graphs show each day averages, not the total. The extreme changes in stem length and leaves in both “medium water” graphs was the result of death of our plants. We left this in to demonstrate the effects of over stressing our plants with too little water. It was intended to differentiate the wild type from the aba and abi mutants, but unfortunately it effected all plants. This of course would be an aspect of which we would change in the redo of the experiment
Thanks for the nice comments! I have enjoyed working with you all. If you make a poster or figures with your results, I would love to see it. :) Hope you are enjoying Thanksgiving!
It’s great to see that teams from your school are wrapping up and posting conclusions. Enjoy the final stages of your project, and feel free to post any final comments or questions you have for your mentors.
Hey Sven, thank you so much for helping us on this arabidopsis journey. I do truly think I can plant now, and although it’s been a lot of work, I can definitely say that I had a radical time. Your input has really shaped our project, and your patience and knowledge have been critical for our success. Thank you so much!
Thank you so much for all of your help and feedback. You have been so responsive and nice. Our project is a lot better because of you.
Hi Sven, thank you so much for all your help throughout our project. Especially with the abscisic acid solution, that was really helpful. Once again thank you so much for all of your help!
Does this tray setup really keep the ABA water from getting into the no ABA tray? Just curious, because I see that both trays have holes and are in the same larger tray.
We sprayed the ABA water directly into the ABA pods outside of the water filled bin and then placed them next to the no ABA plants. Obviously in hindsight we might have separated the bins better in order to eliminate any contamination, but they should still be accurate.
Wow, these ones are doing good. The abi1-1 plants look like they are bolting much faster than the others.
Happy Monday! Hope your plants are doing well. Are you starting to see differences between the different genotypes or treatments?
Yes, we have seen a clear difference in growth between plants with ABA and without ABA. Plants with ABA appear to have shorter stems, which makes sense because ABA limits dormancy. We have not noticed much color change in the leaves except for yellowing that has resulted from abscission and leaf loss in the ABA plants, which also seems to fit the predicted outcome.
When you planted the seeds, how did you put them onto the pods? Did you try to get a specific number of seeds per pod? (I know the seeds are super tiny! I used to do a lot of research germinating individual Arabidopsis seeds. I spent hours staring at seeds under a microscope so that I could put them on petri dishes in 10 rows of 10 seeds each per plate.) I was just curious because I noticed that some pods appear to have a lot of seedlings and others have only a few or none.
For the most part we put 3 seeds in each pod. Since we had some left over, we wanted to make the most of them, so for some pods we do have over 3 seeds. Of course we could have just as easily accidentally put one or two more seeds in, and not all of the seeds germinated, which could be a response to the ABA.
Hi! All of our plants except one in the low water tray has died, and then same for medium, but high water is still growing rapidly in most pods. Pictures coming soon.
Oh my! That's so sad. So it sounds like the low and medium water treatments were a bit too low. But the high water treatment must be a good level. You can still use that treatment to test the effects of the different mutants +/- ABA.
You should also think about how you might plant the experiment differently if you did it again. These sorts of things happen a lot in real scientific experiments and then we have to learn what caused this to happen so that we can improve our next experiment. For example, one option would be to increase the low and medium and high. However, perhaps your low, med, and high were ok, but the plants were too young. Maybe they would have survived these treatments if there were a little older? If that were the case, you could try starting will all of them at "high" treatment until they get to a certain stage. Once they are big enough, you change the watering treatment from all high to low, med, high. Think about any other options that you would try if doing this again.
Looking forward to the pictures! Do you see any differences between treatments and/or genotypes (bigger/smaller?, color of leaves?)
Thanks for the photos! Looks like you have some healthy looking Arabidopsis plants. :)
Post some photos of your plants if you get a chance. Would be cool to see your setup.
We have now filled our methanol-abscisic acid solution up to a liter with water in order to dilute the high concentration. Is this amount of dilution safe enough for our plants?
Hmm... So you had 20 mL of methanol at the start, so that means you now have 2% methanol? I think 2% methanol should be low enough to not harm your plants. If it smells strongly of methanol when you spray it, then you might consider diluting it even further. But I think that you should be low enough to be safe.
Another thing to keep in mind is that high concentrations of methanol (like your initial 100% methanol with ABA in it) can be dangerous to your health if the spray is inhaled, so it is best to always use them in the chemical hood. But when you dilute it to a far lower concentration in water, it becomes safer to use.
So based on your diagram from the pdf, I understand that you are exposing Ler wt, aba1-1, and abi1-1 to high, medium, and low watering. And for each of these three conditions you have a treatment of spraying with ABA or no spraying with ABA. That sounds like a nicely balanced experiment.
So you can see the differences between these genotypes under three different watering regimes and see if addition of ABA rescues any effects that are seen in the ABA-related mutants.
Hi Sven, sorry for not updating you recently, this pdf should work, thank you for being patient with us!
Thanks for the pdf! I can read it now. :)
This upload is just a rename of the previous upload, we realized that we should specify what we are sending in, this is our actual experimental proposal.
I still can't read the gdoc file, could you please upload it in another format like .doc or .pdf. Google Docs can export either of these formats. Thanks!
Here are the first 6 daily logs (including today) of our planting process:
Day 1: Planted all seeds according to our diagram (one wt seed accidentally placed in abi1-1 pod and one abi1-1 seed accidentally placed in wt pod)
Day 2: Switched bins for flatter surfaces, no germination
Day 3: Germination of all seeds except for 5 of the pods
Day 4: Germination of all but one pod, added 100 more mL of water to each tub
Day 5: Third day of germination, 2 pods without germination (Medium water, ABA wt, and low water ABA, abi1-1)
Day 6: Refilled each tray to 400mL water, made ABA solution (50 mg ABA solution + 20mL methyl alcohol), sprayed this ABA solution on ABA plant group
Ah, this answered what you meant by "soak" the plants. You are bottom watering them, by placing the pot (or I think you are using pods) into the tub. That will work well, I think.
For your "Day 6" you say that you mixed 20 mL of methanol with 50 mg of ABA. And then you sprayed this on the plants? I am worried that you are going to hurt the plants by spraying such a high concentration of methanol on the plants. As I mentioned before, it would be best to initially mix the ABA powder in a small quantity of methanol (to get a high concentration solution) and then dilute this into a large quantity of water so that you majority of the liquid is actually water that you are spraying on the plants.
We are planning on soaking the plants in water for 3 days a week, 2 days a week, and 1 day a week for high, medium and low water levels respectively. And yes, we will do the same length of soaking for ABA and no ABA plants. What do you think about 400 milliliters for a standard measure?
400 mL sounds like a fair amount to use. How will you soak them? Are they growing in soil or on agar? Will you just dip the top of the plant in or submerge the whole plant (and soil)?
When you talked about how long to soak the plants, is that happening every day? Every 2 days? Once a week? You could try to do the same length of soaking or watering with ABA and no ABA solution, but just decrease how many times you do it in a week. Like how you can water stress your plants at home if you forget to water them one day.
We are planning on soaking each plant type in water for different amounts of time. Low water would be 1 minute, medium water would be 2 minutes, and high water would be 4 minutes. Essentially doubling the amount of time each plant would be soaked.
The aba1-1 and abi1-1 mutants would germinate better than the Ler wt because of either their lack of production of abscisic acid (aba1-1) or unresponsiveness (abi1-1).
I couldn't see the gdoc file yet, but just make sure that you separate the two factors of ABA and water level. So you would want a low, med, high with ABA and a low, med high without ABA. Maybe you already had this explained in your file, but I just wanted to mention it.
Regarding the soaking time, I am not sure if you will see a clear difference with 1 min, 2 min, 4 min, but you might. (It's an experiment, so I don't know the answer either. ) You could make the differences even bigger, like 1 min, 10 min, 30 min. But I am sure you may have to work around the constraints of the length of your class period.
In our document we have a diagram of our experiment, and have by default put that each seed variation (ex: aba1-1 with added abscisic acid and high water) would have 10 seeds tested each. This would account for possible germination failures but also comes out to 160 seeds total. Obviously we believe that many of these will die, but we are still unsure if limiting the number to 8 of each seed would make anything easier/more efficient.
Unfortunately, I am unable to view the file that you uploaded. It looks like it is a gdoc file from google docs. Could you try exporting it as a pdf (or word doc) and uploading?
I think more seeds is always better and it won't be too hard because Arabidopsis seeds are tiny and you can fit lots of them on a plate or in a pot. I also agree that you may want extras to account for germination failures.
We want to know the proper amount of methanol uses to dissolve ABA powder, does 5ml for 15mg sound right? Also should we add ABA before or after germination, the experiments we are looking at did it after 3 days of growth in a petry dish. Please get back to us on this ASAP. Thanks.
See my post for the full explanation about the ABA to add. The simple answer is that you want to make a concentrated stock in methanol and then add a small amount of that into the water to get your desired concentration before you use that in your experiment.
I think it will probably be best for you to add ABA only after 3 days of growth. The reason is because you will not get much seed germination if you add ABA before the seeds sprout.
Sorry for the delayed response, it doesn't look like I have been getting all of the notifications.
In response to your questions: (sorry if you already figured this out)
For ABA powder, it will depend on the final concentration that you want. For your experiments you probably want to make a more concentrated ABA stock in methanol and then pipet a small amount of this into the water that you add to the plants.
A good stock concentration might be 10 mM (milli molar). To calculate a molar concentration you need to know the molecular weight of the compound, in this case ABA. That should be written on the tube somewhere and (I googled it) should be 264.32 (if it is different, use what the bottle says). The molecular weight represents the number of grams in 1 mole of ABA. So if we want a 10 mM stock, then we want 0.010 moles of ABA per Liter of solution. Let’s say we want to mix up 10 mL of solution (which is 0.010 Liters).
So 264.32 grams/mole x 0.010 moles x 0.010 Liters = 0.02643 grams of ABA, which is 26.43 mg (milligrams). So you would add 26.43 mg to a tube and then fill it to a total of 10 mL of Methanol. If the amount to make is only 1 mL, then it would be 2.64 mg of ABA into a total volume of 1 mL. Then you would have your 10 mM stock solution. If you want a 100 mM solution in 1 mL of water, then you would add 26.43 mg of ABA powder into a total volume of 1 mL of methanol. For a 1 M solution in 1 mL of water, you would add 264.32 mg of ABA powder into a total volume of 1 mL of methanol.
Hope that makes sense. Ask questions if it doesn’t and I can help. You want to make your stock solution a high enough concentration so that you don’t add too much methanol into your ABA-water for the plants. Try to keep the amount you add to less than 1 mL as a rough guide.
So after you have your stock solution (10 mM or 100 mM or 1M solution), then you can use that to add to your water to get your final concentration. 5 µM (micro molar) or 10 µM ABA should have a good effect on your plants, you can go higher, but 100 µM in the water is probably too high and may cause more stress for your plants. Plant hormones like ABA work at very low concentrations! You can go lower, 1 µM or 2µM ABA will still have a mild effect.
If you start with a 10 mM solution and you want a 10 µM solution in water, you need to know how much water you are mixing up. So if you mix up 100 mL of water with ABA (which you can add to your plants), then you would want dilute your stock to get 10µM. The metric system makes it easy to change units because 1 M = 1,000 mM = 1,000,000 µM. So we have 10 mM (10,000 µM) and we want 10 µM, so it will be a 1:1000 dilution. So for 100 mL of solution, add 100 µl of your 10 mM stock solution. If you want to make 1 Liter, add 1 mL of the 10 mM stock, or use a 100 mM stock and add 100 µL.
I hope that helps!
How are you planning to manipulate water level for the plants?