|Whiteman Laboratory at the University of Arizona||
We injected bacteria directly into the leaves of Cardamine. To do this we took advantage of natural structures in the plant leaves themselves. It is not obvious, but plants have microscopic openings on the underside of their leaves called stomata. The stomata are involved in gas exchange to intake carbon dioxide and expel oxygen. Fortunately for us, we can use these openings to force fluid into the leaf. Using a blunt syringe we can apply pressure to a volume of bacterial suspension and inject it straight into the leaves. The bacteria will pass through the stomata and profuse through the internal tissue. This method has the benefit of not damaging the outside of the leaves themselves. We will let the infections incubate for a few days to allow the plant to mount an anti-bacterial immune response. We will then observe how this affects herbivory by Scaptomyza.