Here we go....

So this week I continued to work on my new allelopathy test project but with few changes than what I explained last week. And that was about putting some crumbled leaves inside the petri dishes with seeds but Matt decided that I don’t need to do that anymore.

I had my petri dishes ready since last week and I also had the Sycamore, Sun flower and Orange tree’s leaves ready and completely dried out for this week experiment. On Monday I found out that the last minute leaf collecting saved me a lot of time because the leaves dried out naturally in the lab during the weekend.

Oak branches

Oak and Mesquite leaves

Anyway, last week due to my short time in the last day I couldn’t make it to collect the Oak and Mesquite leaves, so I took another journey around the campus to collect the leaves. The Oak leaves are small and it’s kind of hard to collect the full basket, specially the basket that I have because it has a big holes on it and the leaves kept falling. But this time I was lucky and one of the maintenance guys saw me and cut some of the branches for me, he made my job much easier. Since I needed the leaves to be dry, I let them to dry for a day but it didn’t work well, so with Matt idea I ended up with spread them on separate trays and put them in the oven for one more day to make them dry faster and save me some time. 

Oak and Mesquite leaves after one day in oven

Those two days that I was waiting for the Oak and Mesquite leaves to get dry, I started the experiment with my other leaves. Grinding the leaves was the first step and I start doing it with mortar & pestle, which wasn’t that easy and would take a long time, since technology is always helpful instead of mortar & pestle I used blender to grind the leaves and I got pretty good powder of each one.

Blender was a good idea but too messy!

 Then I made a 2% solution for each sample, by weighing 20.0 gr of the sample (leaves powder) and adding 200 mL of DI water to it, I closed the lead with parafilm and let them to stay like that for a day. And finally the day after making the solution, I did water the petri dishes with 5 mL pipet. 

2% solution of each treatment

After I got done with watering and using the solution, I made a 50% solution with the remaining solution and I added another 100mL to it. And I set up another set of petri dishes next to the other one in order to test the 50% solution on germination of the seeds and comparing the both result together. So this week I was able to finish all the plates and watering them and also fold all of them with parafilm to prevent the evaporation. And now I have to patiently wait for a week or more to see the result and start counting the seeds again.

50% solution of each treatment

petri dishes water with 2% solution

Petri dishes water with 50% solution

Redo the test

Sadly this week I couldn't be in the biology lab like I used to, because the school was close on Monday for the President Day and I lost some hours, but on the other hand since I’m always busy and work every day even weekends, it was a right time for day off because I could celebrate my birthday and spend some time with my family and friends.

But back to my alellopathy project I believe that I mentioned in my last blog that Matt told me to redo the alellopathy test but in a different way. So basically I won’t do the leaf extraction again, and what I’m going to do this time is to take some crumpled up dried out leaves and put them in the petri dishes with the seeds and then water the petri dishes with just distilled water (5mL each)and determine if there’s an effect on germination of any of them.

120 set up petri dishes

So far I set up all the petri dishes, which are 120 petri dishes, just like I did before for leaf extraction. I cut off the filter papers, two for each petri dish. Then I started to label all the dishes with the name of the seeds and treatments. When I got done with labeling, I used the same seeds, radish, chard, lettuce and carrot. And I started to count 25 of each type of seeds and put them on the labeled dishes between the two filter papers. After set up the petri dishes I went to Phoenix College garden and collected the leaves from Sycamore tree, Sun flower, Orange tree, Mesquite and Oak tree. That’s where I stopped this week and for the next week I need to dry out some leaves, I’ll put some crumpled up leaves of a certain amount in the petri dishes and then I’ll water the petri dishes with 5 mL. 

Finally germinated!

This week I didn't do a lot but like I said last week, I kept continue on the allelopathy test. So mostly what I did this week, was counting the seeds, it sounds pretty easy and funny but it was such a pain to make them separate from each other and count them and it took a long time from me I can say pretty much the whole week, because I should count them a week after creating them and I needed to wait for some seed. Maybe you ask yourself that why should I doing that and spending that much time on them, but the seed counting it’s the last step which gives us a clear answer depends to the seeds germination. So what I did was counting the germinated seeds in each petri dish individually, which was 5 petri dishes of each seeds for every treatment. And then I started to do some calculation, getting the mean of petri dishes for each treatment and graphing the average of each treatment also I calculated the standard deviation to graph a better error bar. According to the result from the table and the graph I determined that chard has the best germination and all the chard seeds germinated in all treatments except in one dish of sycamore treatment. You can see better in the chard germination graph.

Radish and lettuce seeds germination had almost the same average of germination and the speed of germination. But carrot had the lowest average number of germination compare to the other seeds. You also can see all of them in the graphs.

Unfortunately according to these results there was no inhibitor, which I don’t know that I should say it’s bad or good but I was more hoping to find the inhibitor in the garden, and I got germination in all of the petri dishes just with a different number in germination which makes sense. Also I would like to mention that during the seeds counting I observed something different about the Orange tree compare to the other trees (Sycamore, Sun flower and Oak), which was the leaf color. So I got the germination on all the petri dishes that treated with Orange leaf extract like the others, but their leaves was more yellowish than the other petri dishes with other treatments. And it’s more clear and obvious in the picture below.

I’m not 100% sure but since we couldn’t get the answer that we’re looking for from this experiment, probably I’m going to start another way to test them.

Allelopathy test

 This week I kept continue to work on the allelopathy test. After setting up the petri dishes with seeds (radish, lettuce, chard and carrot) for test, I needed to get ready for the next step, which is creating leaf extraction and it’s obvious that the first things that I needed was whole bunch of leaves. So first, I went to the Phoenix College garden and searched around it to find the trees; Sycamore, Orange, Oak and sunflower, and collected the leaves. So I collected a full wire basket leaves of each one of them, then in the lab I started the leaf extraction. Then I washed a white plastic tub really well, maybe you ask yourself why I’m telling you the color and it doesn't matter, but the truth is that it does matter and it’s really important in this experiment because in leaf extraction we need to see the color change in water, so using the white tub it’s the best way to recognize that. After that I got 1 Liter DI water in a flask, and placed the leaves basket in middle of the tub. Then I poured the DI water all over the leaves and waited for couple seconds to get all the water inside the tub, and then swash the basket of leaves around and poured the water back into the flask.

 Again poured the same water in the flask on the leaves and after swashing, pour the water back to the flask. I kept repeating it about 30-40 times, until water started to change color slightly. And then when it changed color slightly, according to the research, that’s supposedly five percent extraction and that’s the standard extraction that you use for some experiments like that. Then I started watering the petri dishes with the seeds on them, with pipet and added 5 mL of the leaf extract to each petri dishes. So the sunflower was the first leaf extraction, I watered all the sunflower treatment petri dishes and foiled each five of the same seeds together to prevent the evaporation. Since I should do once at a time, it took me more time but I could finish the leaf extractions and watering the seeds in two days.

sun flower leaves

sun flower extract

Orange leaf extract

Sycamore Leaves

Sycamore leaf extract 

Sycamore leaf extrac

Oak leaves and leaf extract

ready petri dishes

Next week I’m going to open them and see the germination, also to check which ones and how many seeds of each petri dishes grow, and do some percentage and calculation. I'll also start doing the same experiment on some other trees and plants.