Fitness trade-offs associated with pesticide resistance in Homalodisca vitripennis

The glassy-winged sharpshooter, Homaldisca vitripennis, has been one of the most notable vectors of Pierce’s Disease throughout the United States. The most utilized practice of controlling this pest-disease complex is through the use of pesticides like imidacloprid. With heavy insecticide use over the past two decades, populations of glassy-winged sharpshooters have developed resistance to the neonicotinoid pesticides being used. The purpose of this study was to determine potential consequences of resistance on various life history parameters associated with resistance to pesticides. Bioassays of the susceptible population collected in Kern county CA showed some resistance to neonicotinoids while bioassays of the resistant population showed 10x higher resistance compared to the susceptible population. The susceptible population had a shorter preoviposition with 12.22±.83 days from adult emergence to first oviposition while the resistant females took 25.68±5.35 days to oviposit. The susceptible females laid an average of 380.13±46.02 eggs while the resistant females laid an average 190.13±31.56  eggs. Additionally, the susceptible females exhibited longer lifespans compared to the resistant females. The susceptible females lived an average of 72.77±7.58 days while the resistant females lived on average 51.73±6.03 days. Understanding if there are any fitness tradeoffs associated with pesticide resistance can help develop better IPM strategies that are more efficient and effective at controlling the pest population. Through the use of IPM strategies and planned use of pesticides, the glassy-winged sharpshooter populations can be controlled preventing the spread of pierce’s disease.