LE3 .A278 2021

2021

Hillier, Kirk
Moreau, Debra

Acadia University

Bachelor of Science

Honours

Biology

Biology

Grape phylloxera, Daktulosphaira vitifoliae, are one of the most economically important insect pests of commercial grapevines. Since discovery of their damage to grapes in the 1860s, many methods to manage this species have been attempted. The most successful management method for D. vitifoliae has been the use of resistant rootstocks. Unfortunately, as new, more virulent D. vitifoliae biotypes emerge, these rootstocks are becoming more susceptible. Chemical management options for D. vitifoliae are limited and are most effective when applied to D. vitifoliae at the crawler stage. The objectives of this study were to (1) determine the seasonal dynamics of soil emerging D. vitifoliae populations; (2) relate soil emerging D. vitifoliae population dynamics to leaf gall presence; and (3) relate air and soil temperatures and vine phenology to observed D. vitifoliae populations. The overall goal of these objectives was to determine the most effective time for application of management practices. Traps placed within a block of Marquette grapes were used to collect emerging D. vitifoliae over the 2020 growing season and determine their seasonal population dynamics. These populations were correlated with gall presence, temperature, and vine phenology. Daktulosphaira vitifoliae was determined to have a bimodal seasonal distribution that was significantly correlated with temperature and vine phenology. Gall presence was not significantly related to D. vitifoliae emergence but did reveal that D. vitifoliae populations move throughout the vineyard primarily due to prevailing wind patterns. The most effective time to manage crawlers was determined to be when grapevine phenology stages are around rapid shoot and inflorescence development, and berry development, in combination with soil temperatures ranging from 21-25°C.

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https://scholar.acadiau.ca/islandora/object/theses:3572