Differences in defense response to herbivory across Arabidopsis mutants

Abstract

Arabidopsis thaliana is a model plant for research, and Spodoptera exiqua (beet armyworms) is a common agricultural past that is also used in research settings (Rehrig et. al., 2014). In an effort to find plants that are genetically resistant to insect pests, eight genotypes of Arabidopsis were tested in three experiments involving the armyworms. For the first experiment, 1st instar larva were allowed to feed on the 8 genotypes for a week. The weights of the insects were compared and a qualitative visual performance of the plants showed that most genotypes performed better than wild types, with one exception (EDM1-1, SRFR1-4). The second experiment tested the effects of the plants on the rates of cannibalism for the armyworms. This experiment proved that the insects eat other alive. The third experiments allowed the insects to feed on leaves, and then the leaves were collected at different time points. After RNA extraction, qPCR was performed on the samples to find the relative expression of two defensive genes: LOX2 and JAZ1. Overall, results were varied, but EDM1-1, SRFR 1-4 performed poorly while the individual mutations of EDM 1-1 and SRFR 1-1 performed well when compared to the other genotypes.