Date: Monday, November 7, 2022
Time: 3:00pm
Speaker: Annie Vogel, PhD Introduction Seminar
Title: Modulating Apple Vegetative Growth and Systemic Movement of Erwinia amylovora in Young Orchards
Host: Dr. Tom Kon

Location (Hybrid): 121 Kilgore Hall
Zoom: https://ncsu.zoom.us/j/94283163503?pwd=REFhLzd1bi9CdjVGTjdtZ3Q2bEUrZz09
Meeting ID: 942 8316 3503
Passcode: 917132

 Seminar_Annie Vogel_11.7.22.pdf

Abstract:
Cultural, chemical, and environmental factors impact vegetative vigor, orchard establishment, and systemic pathogen movement in young, high-density apple (Malus x domestica L. Borkh) orchards. In Western North Carolina, rapid orchard establishment due to unbridled growth leads to earlier productivity and profits, but potentially increases disease susceptibility compared to mediated growth. An economically critical bacterial disease, fire blight (Erwinia amylovora), causes bloom and shoot dieback and ultimately tree death if the bacteria reaches the central leader. There are suspected relationships between tree vigor and fire blight susceptibility to a secondary shoot blight infection and movement within individual trees. Through the use of cultural, rootstocks and fertilization, and chemical, prohexadione calcium and acibenzolar-S-methyl, management practices, we attempted to modulate vegetative vigor and investigate the relationship between vigor and fireblight infection. Shoot growth over time, whole tree growth, leaf area index, and quantum yield of photosystem II were measured to quantify differences in vegetative vigor and tree morphology. Disease ratings, colony populations, and bacterial density along the infected shoot at different distances and tissue types were collected to track disease incidence and severity and bacterial movement over time. Results of these studies will dictate grower choices in young orchard systems to maximize orchard establishment while protecting trees from fire blight infection.