Hardcore Flipping! The Hunt for Wasps and an Easy Friday

Well, I may have found something I'm a natural at, which is wonderful, because I'm very slow at all the other delicate techniques...

Anyway, the main thing that we did on Thursday was more work on my project. This stage of the project involved flipping whitefly hosts to determine whether or not they've been parasitized. Well technically, we were looking for eggs, not parasitic larvae just yet. So, the process involved flipping over half of the whiteflies from our specially prepared leaf disks from the other day. If you'll remember, I'm working with Eretmocerus emiratus wasps and Bemisia argentifolii (the silverleaf whitefly). What's cool about this species of wasp (I believe that the other members of the genus do this as well) is that instead of laying the egg inside the whitefly host, E. emiratus lays it underneath the whitefly host, meaning that (1) the larva actually has to chew through the whitefly's thick hide to get to the good stuff, and (2) the presence of eggs is a lot easier to verify than in other wasps, like those of the genus Encarsia, which lay their eggs in the cuticle of the whitefly (dissection is required to see the egg). Also, E. emiratus's ovipositor is especially made for laying eggs underneath hosts, and consequently can't really be used for stinging. So yeah, flipping whiteflies is relatively simple, but very delicate. After locating the target whitefly under the microscope, you have to approach it with a probe and gently turn it over without destroying it or the egg that may be underneath it. This is easily done if the whitefly is about to molt, because towards the end of their instar, the whitefly larvae essentially puff up above the leaf; conversely, this is difficult to do when the whitefly has just molted, because it is very squat and low on the leaf and easily breaks. Did I mention that whitefly larvae are sedentary? They are.

Yesterday, I managed to do five full dishes in the time it took Suzanne, the expert, to do seven, so that's actually pretty good, in case you didn't know. This morning, I did two more, and as it turns out, a female wasp never made it onto either of those, since we couldn't find any eggs. That may have been bad luck, so we're holding onto those. The most important thing we did today was a PCR to determine the identity of those mislabeled wasps from Wednesday. We did get a weird result, so I'll probably discuss it more on Monday. Oh, I also did a series of infestations for my experiment for next week. I did two W+ infestations and two W- infestations. It was wonderfully easy for once because the light was shining on the wasps just perfectly and I could more or less tell the males from the females. I guess I should mention that it's more difficult to tell male and female E. emiratus apart than it is to tell apart the males and females of any other species of wasp at the lab. Even if I can't really tell males from females apart without the microscope, the E. emiratus populations are female-biased enough that I can get the right amount of females without really trying. Unrelated to my experiment, I harvested Encarsia hispida pupae. They're the dark, wiggling ones, by the way, so that was fun.

WEEKEND!