Poster Display
Plant-Insect Ecosystems
Swapna Priya Rajarapu
Postdoctoral Researcher
North Carolina State University
Raleigh, North Carolina
Sai Karthik Gade
North Carolina State University
Raleigh, North Carolina
Angela Chiang
North Carolina State University
Raleigh, North Carolina
Justin G.A. Whitehill
North Carolina State University
Raleigh, North Carolina
Fraser fir (Abies fraseri) is a conifer native to the Southern Appalachian Mountains and primarily endemic to North Carolina. Fraser fir is the premier Christmas Tree in the US and most preferred by consumers accounting for ~40% of all species sold. However, the North Carolina Christmas tree industry must mitigate the impact of multiple biotic challenges including several emerging pest and disease threats. Notably, insect pests with the biggest impact on Fraser fir production have piercing-sucking mouth parts – which is not common for most conifers. Specifically, the invasive elongate hemlock scale (EHS; Fiorina externa) has become the primary concern for eastern US Christmas tree growers due to regulations imposed on the exportation of trees to non-invaded states. EHS infestations cause symptoms that include needle mottling which decreases the aesthetic value and ultimately commercial value of a tree. Recently, the Whitehill lab – Christmas tree genetics program found variation in the susceptibility of individual Fraser fir families to EHS infestation. To identify the mechanisms and traits involved in this interaction we conducted a greenhouse experiment using highly tolerant/resilient and susceptible genotypes. The goal was to dissect resilience within Fraser fir families to EHS at the molecular, biochemical, and microscopic levels. Evaluation of molecular, anatomical, and biochemical changes in trees infested with EHS relative to uninfested trees is beginning to provide novel insights into the mechanisms of EHS resilience in Fraser fir.