Diaphorina citri is a vector of ‘Candidatus Liberibacter asiaticus,’ (CLas), associated with Huanglongbing, (HLB, or citrus greening) disease in citrus. D. citri exhibit at least two color morphotypes, blue and non-blue. Blue morphs have a greater capacity for long-distance flight as compared to non-blue morphs, but little else is known about how color morphology influences vector characteristics. Much of my research was developed to test the hypothesis that blue and non-blue color morphs of D. citri have variation in their immune systems and that these immune systems differences lead to differences in interactions with the insect’s microbiota. I showed that the color morphology of the insect is derived from pigmented cells of the fat body. Non-blue morphs acquire a higher level of CLas in their bodies from infected trees as compared to blue morphs. I used shotgun proteomics to study molecular difference of two-color morphs. Higher abundance of immunity-associated proteins in blue morphs and lower mortality rate due to Beauveria bassiana infestation as compared to non-blue morphs supports our hypothesis. During evolution, D. citri has lost its immunity-related pathways and proteins, which has been thought to favor the development of endosymbiosis with microbial partners. D. citri harbors ‘Candidatus Profftella armatura’ (Profftella), an endosymbiont with a presumed defensive role in the insect’s biology. Profftella produces large quantities of diaphorin, an antimicrobial polyketide compound. While the diaphorin biosynthesis pathway inside of the bacteria is inferred from sequencing of the Profftella genome, I hypothesize that diaphorin biosynthesis requires the initial precursor molecules that are derived from the insect. I hypothesize that the precursor is S- methylmalonyl-CoA, which is synthesized by the D. citri enzyme propionyl CoA (PCC). To test this model, I used virus induced gene silencing to reduce the expression of the PCC gene, and silenced insects were subjected to diaphroin analysis using targeted ...