Regulation of anti-herbivore defenses: Plant response to mycorrhizal colonization and simulated aboveground herbivory

Abstract

One key symbiosis in the prairie is the mutualism between plants and soil microorganisms, namely arbuscular mycorrhizal (AM) fungi. In addition to assisting the plant through enhanced nutrient uptake, AM fungi can also aid in water uptake and production of secondary compounds. One example of these compounds is latex, a white, milky substance which gives milkweed its common name. Additionally, AM fungi can influence plant defenses by interacting with the jasmonic acid (JA) pathway in plants. I hypothesize that AM colonization of the root system will induce latex production to a greater extent than nutrient addition without AM associations (nonmycorrhizal). I also hypothesize simulated aboveground herbivory (jasmonic acid) will likely induce enhanced latex production. Finally, I hypothesize plants associated with AM fungi and subjected to simulated herbivory will produce the greatest levels of latex production. My research indicated none of the hypotheses were supported as there were no statistically different results. However, my research did point to other areas of study it may apply towards. Further research regarding different types of simulated herbivory, using different species, greater exploration of nutrient availability on latex production, and further study of the effects of mycorrhiza on plant defenses could prove fruitful.