http://dx.doi.org/10.14288/1.0434662
department or school: Science, Irving K. Barber Faculty of (Okanagan)
department or school: Biology, Department of (Okanagan)
data provider: DSpace
degree campus: UBCO
creator: Mahovlic, April
issued: 2023-08-03T16:58:38Z
issued: 2023
related degree: Master of Science - MSc
degree grantor: University of British Columbia
description: Grapevine leafroll-associated virus 3 (GLRaV-3) and Grapevine red blotch virus (GRBV) are economically important viruses in British Columbia that decrease grapevine health and fruit quality. This study aimed to investigate the use of crop thinning to mitigate negative impacts of GLRaV-3 and GRBV on vine health and fruit quality of ‘Merlot’ and ‘Cabernet Sauvignon’ vines in the Okanagan Valley, British Columbia, as well as understand the role of virus titer in disease severity. A commercial vineyard site with adjacent ‘Merlot’ and ‘Cabernet Sauvignon’ blocks was selected in a complete-randomized trial conducted in 2021 and 2022 growing seasons. GLRaV-3 and GRBV vines were paired 1:1 with healthy vines, and each pair was designated a cropping treatment, applied at pea-sized berries stage, of either 1.5 clusters per shoot (1.5 C/S) or 1.0 cluster per shoot (1.0 C/S). Vine health parameters and virus titer measurements were taken four times in the season and fruit quality measurements were taken once at harvest. GLRaV-3 infection increased crop load and titratable acidity (TA), and decreased Brix. Crop thinning decreased TA and anthocyanins and increased pH of healthy vines. 1.0 C/S GLRaV-3 vines had significantly higher pH than 1.5 C/S GLRaV-3 vines. However, all these impacts were year and cultivar dependent, suggesting that crop thinning is not sufficient to mitigate GLRaV-3 impacts in ‘Merlot’ and ‘Cabernet Sauvignon’. GRBV had more consistent impacts on vine health and fruit quality, as infection decreased leaf greenness (SPAD), increased berry weight, cluster weight, pruning weight, crop load, TA and pH, and decreased Brix, yeast assimilable nitrogen (YAN). Crop thinning did not significantly impact GRBV infected vines, thus was not sufficient to mitigate virus effects. GLRaV-3 and GRBV titer was highest at pea-sized berries and harvest, and may follow a seasonal pattern corresponding to temperature changes. Viral titer was negatively correlated with photosynthesi…
aggregated CHO: https://circle.library.ubc.ca/rest/handle/2429/85380
note: Mitigating the effects of Grapevine leafroll-associated virus 3 and Grapevine red blotch virus in ‘Merlot’ and ‘Cabernet Sauvignon’ using crop thinning, and investigating the role of virus titer in disease severity in the Okanagan Valley, British Columbia by April Mahovlic B.Sc. Hons, University of British Columbia Okanagan, 2019 A THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE in THE COLLEGE OF GRADUATE STUDIES (Biology) THE UNIVERSITY OF BRITISH COLUMBIA (Okanagan) July 2023 © April Mahovlic, 2023 ii The following individuals certify that they have read, and recommend to the College of Graduate Studies for acceptance, a thesis/dissertation entitled: Mitigating the effects of Grapevine leafroll-associated virus 3 and Grapevine red blotch virus in ‘Merlot’ and ‘Cabernet Sauvignon’ using crop thinning, and investigating the role of virus titer in disease severity in the Okanagan Valley, British Columbia submitted by April Mahovlic in partial fulfillment of the requirements of the degree of Master of Science . Dr. Miranda Hart, Faculty of Science, University of British Columbia Okanagan Supervisor Dr. José Ramón Úrbez-Torres, Summerland Research and Development Centre, Agriculture and Agri-Food Canada Co-Supervisor Dr. Kevin Usher, Summerland Research and Development Centre, Agriculture and Agri-Food Canada Supervisory Committee Member Dr. Michael Deyholos, Faculty of Science, University of British Columbia, Okanagan Supervisory Committee Member Dr. Simone Castellarin, Faculty of Land and Food Systems, University of British Columbia University Examiner iii Abstract Grapevine leafroll-associated virus 3 (GLRaV-3) and Grapevine red blotch virus (GRBV) are economically important viruses in British Columbia that decrease grapevine health and fruit quality. This study aimed to investigate the use of crop thinning to mitigate negative impacts of GLRaV-3 and GRBV on vine health and fruit quality of ‘Merlot’ and ‘Cabernet Sauvi…
has type: Thesis/Dissertation
date issued: 2023-09
is shown at: 10.14288/1.0434662
language: eng
degree discipline: Biology
provider: Vancouver : University of British Columbia Library
publisher: University of British Columbia
rights: Attribution-NonCommercial-NoDerivatives 4.0 International
rights URI: http://creativecommons.org/licenses/by-nc-nd/4.0/
scholar level: Graduate
contributor: Hart, Miranda
contributor: Urbez-Torres, Jose Ramon
title: Mitigating the effects of Grapevine leafroll-associated virus 3 and Grapevine red blotch virus in ‘Merlot’ and ‘Cabernet Sauvignon’ using crop thinning, and investigating the role of virus titer in disease severity in the Okanagan Valley, British Columbia
type: Text
identifier URI: http://hdl.handle.net/2429/85380