Weekly Seed Activities

My daily activities in lab really depend on what point of the experiment we’re at. Since my project is such a giant experiment, it takes up most of my time during the day, though I do help work on another smaller experiment that’s also going on. I generally arrive in lab around 10 AM. The more intense days have me working continuously from 10 to 5, while on the easier days I have time to read papers and work on some smaller assignments (like blog posts or the upcoming chalk talk).

The first few weeks at lab were pretty intense, since we all had to work together to prepare the experiment due to the sheer quantity of plates (2,304) needed. In the mornings, I would cover an entire lab bench in petri dishes (it turns out your standard lab bench can fit exactly 450 3 millimeter petri dishes on it). Then we needed to prepare the agar, which can fortunately be done on a larger scale using the autoclave machine down the hall in the Biological Sciences building. This way, we can heat up around 12 bottles of agar at once in about an hour. After filling up all the plates, they needed to be chilled overnight so that no mold or fungus grew in the agar. Making all of the plates basically took up the entire first week.

The second week, we had to put 20 Arabidopsis thaliana seeds in each plate. The maternal plants for this project were grown before the program started, but a bunch of plants of each genotype were grown, and then placed in their respective simulated environments. Each of the plants had to be wrapped in a plastic tube in order to prevent cross-pollination. Then, at maturity, the seeds of each plant were collected into tubes, which I then placed into their respective plates. Since the seeds are extremely small (not much more than a speck), I had to use a thin probe and place them one by one on the agar. Then, trays with filters were filled with 36 plates in order to simulate a certain light quality environment. After being filled, we had to take them to temperature-controlled chambers that are either down the hall in BioSci, or in the phytotron (a rather dark and scary place filled with dozens of tall, humming, machines) in French Science.

I was able to start doing germination censuses for the project in week 3. This involves taking the trays out of their chamber, examining the plates under a microscope, and counting the number of seeds that have germinated (which is when you can see the radicle poking out of the seed coat). If all of the seeds are fully germinated, then they can be thrown in a bin to be autoclaved (which kills all of the cells so that they don’t cross-pollinate with natural genotypes!). Then the trays go back in the chambers. The whole process is usually finished by lunch, especially since we have 3-4 people helping out at once. The rest of my day is spent getting caught up on papers or taking care of other plants down in the phytotron. By next week’s census, I should have enough data to begin analyzing the results!

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