End of Season Wrap-Up

!S1080015While this post is meant to be a wrap-up of everything that I’ve been doing this summer, I must add the caveat that my research will finish up for the summer next week. Today marks day 4 of the caterpillar milkweed treatment, the 72 hour and final sampling session was done at 1 pm and the caterpillar and control treatments are both finished. Next week I will be running the simulated herbivory treatment, but for now I am able to celebrate because the experiment with living creatures is over! So this summer I developed a method and protocol for the High Pressure Liquid Chromatography portion of my experiment that I will be conducting this fall. The method development included figuring out how to run batch samples in the HPLC as well as how care for the equipment. This summer I also did field work for several weeks during which I was measuring natural populations of milkweed, and I was able to take samples that I may be able to compare to my research plants in the greenhouse. The greenhouse plants I was able to keep alive and healthy for the entirety of the summer, even though milkweed strongly prefers being out in a field than pampered in a greenhouse. To sample the plants we took latex samples, trichome samples, and tissue samples. The latex samples I have weighed already, and the trichome samples will be counted in the fall semester. To prepare the tissue samples I flash froze them in liquid nitrogen and then freeze dried them in a lyophilizer. I’ve read what feels like countless papers on milkweed research, Monarchs, and plant defensive responses and have begun to write the introduction and methods sections for my senior thesis, which will come in handy because the less writing I need to do in the fall and spring the better! The caterpillars I am going to continue to raise for the next couple of weeks until they are butterflies, and some of them I will test using the HPLC method I am using for the milkweed. This is purely exploratory, but from watching the caterpillars grow as they ate the milkweed it was interesting to see that some caterpillars grew more than others in the 72 hour treatment period, and it seemed to be correlated to the size of the plants they were eating. This may also relate to the low and high density treatments of the milkweed. All in all, this summer has benefitted me in several ways: I got to expand my skill set for conducting field research, I got to conduct experimental research in a greenhouse which was entirely new for me, and I have had the chance to work with an HPLC that I will continue to use through the semester.

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Day one of the actual experiment is here!

S1050022So today I finally got the caterpillars! Thanks so much to Rose Franklin in Pennsylvania for shipping them on Saturday so we could get them on time! Here’s a picture of one of our little guys on one of our test plants. Each plant that is in a caterpillar treatment tub was given one caterpillar. They were placed on the plants at 1 this afternoon so we will start sampling the plants at 1 pm tomorrow at the 24 hour mark. It’s interesting working with living creatures. I’ve been working with the plants since last november from when they were just seeds sitting in a fridge, and I’ve become very protective of them. Granted, a lot of that came from me needing the plants to be alive for this week when we are actually running the experiment, so earlier in the summer when some plants started showing signs of distress I got very concerned with their well-being. The caterpillars on the other hand I instantly bonded with, they are so cute! There was only one that I didn’t really like, while I was putting caterpillars onto the plants in the cages the rest I kept in a box. One of the larger caterpillars almost instantly began to eat a smaller caterpillar during the 5 minutes they were without a food source! (I had enough caterpillars so losing one didn’t set us back at all, but caterpillar cannibalism was quite a shock) Once they were on the plants they stopped trying to eat each other! Now all I have to worry about is caterpillars moving from one plant to another, but I am going to be monitoring their movements multiple times a day so if a caterpillar does move to another plant within a tub we will have it recorded. S1050014

Caterpillars are on their way!

Hey everyone! So I know that most people are finishing up their research projects this week, but I am going to be running the biggest part of my experiment this week! The HPLC method has been developed, the plants are doing fine, the cages are all up in the greenhouse, and we are finally getting the caterpillars to run the experiment! Unfortunately, we won’t be getting them from the original distributor that we ordered from due to time constraints, but I was able to find a wonderful butterfly farm in PA and they were able to ship them yesterday! So just a review of what we are using the caterpillars for: we have 18 cages with tubs of high and low density plants, 9 of each type. There are 3 treatments: caterpillar, manual damage using a hole-punch, and no damage. The caterpillars will be on the plants for a total of 72 hours, and that will be the end of our recording time. During those 72 hours we will take samples of all 3 treatments and then prepare them by flash-freezing and freeze-drying so that I may run HPLC on them during the fall semester. As an added bonus, after the experiment has run we will be rearing the caterpillars in two butterfly cages in the greenhouse! We hope they will add another splash of color to our already personable greenhouse! I will be posting some pictures during the experiment this week of the caterpillars when they are finally on our humble milkweed plants:)

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Triumphs are so rewarding

While I am sadly still waiting on caterpillars to come to campus, I have been working on several exciting things in the lab. Since I am using HPLC to analyze cardenolide content in the milkweed leaf tissue after my experiment is finished I decided to actually work with the instrument to create a method that would process large batches of samples so that I don’t have to run them one at a time (I will have about 120 samples and each one will take a 45 minute run time on the HPLC so you can see why the latter is less than appealing). The HPLC that I am using hasn’t gotten much attention so there wasn’t a standard operating procedure for using it, and since the software is quite complex I decided that this week my goal would be to create a method file that would run practice samples (for 5 minutes each since it is just method development at this stage) and then initialize a shutdown procedure that will save energy by turning the instrument off when the batch is finished running. Thank goodness for the assistance and support of Jon Dalgleish we got this to work! After a week of long days and tiring nights we have figured out how to manipulate the HPLC to do exactly what we want, which means after I finish my experiment with the caterpillars in the greenhouse I will be left with only sample processing in the fall. It was such a great feeling to reach this achievement this week!

Winding Down Field-Work

The start of this summer’s research has been so busy because we do the bulk of the data collection in the field before July. So, while I’ve been establishing methods for plant tissue preservation and practicing with them, we’ve also spent time at Blandy Experimental Farms and this upcoming weekend we are headed to Presequile National Wildlife Refuge, for our last weekend of field-work. The most exciting part of getting ready for field work for Presquile is that it is an island so we have to anticipate all of our needs for both lodging and data collection, so the pressure is really on! I’m also kind of hoping to have some spare time to do a little bird watching because I bet it is amazing in the early morning. The flowers on the milkweed at our Yorktown site are starting to bloom, and it is really drawing the butterflies out which is so fun to look at when it starts to get really hot in the middle of the day and it may be easy to get distracted, so fingers crossed they are also blooming at Presquile. I’ll be checking back in with photos from the next research trip and some lab updates in a week or two!