RT Journal Article SR Electronic T1 Evaluation of Budbreak-Delaying Products to Avoid Spring Frost Injury in Grapevines JF American Journal of Enology and Viticulture JO Am J Enol Vitic. FD American Society for Enology and Viticulture SP ajev.2020.19074 DO 10.5344/ajev.2020.19074 A1 Hongrui Wang A1 Imed E. Dami YR 2020 UL http://www.ajevonline.org/content/early/2020/01/22/ajev.2020.19074.abstract AB Most viticultural regions in the world annually sustain spring frost injury-associated yield loss. Researchers have developed sprayable products to prevent spring frost injury by delaying budbreak. The goal of this research was to evaluate the efficacy of novel products, including Amigo oil® ProTone®, and FrostShield® to delay budbreak and their effects on vegetative and reproductive growth in grapevines. Early budbreaking cultivars, La Crescent and Marquette, were used in field experiments in 2018 and 2019 and in a growth chamber experiment in 2019. Treatments included a control (no spray), 10% (v/v) Amigo oil, 500 mg/L S-ABA ProTone, and FrostShield. In field experiments, FrostShield consistently delayed the budbreak of both cultivars for 4 to 6 days, while the other two products showed a very limited effect. In addition, FrostShield did not affect cultivars’ vegetative or reproductive growth. In the growth chamber experiment, FrostShield delayed the budbreak of two cultivars for more than 2 weeks, while the effect of the other two products was inconsistent between cultivars. Our results indicate that FrostShield outperformed Amigo oil and ProTone by consistently delaying budbreak without negatively affecting vegetative or reproductive growth, suggesting that FrostShield might be an effective product to prevent spring frost injury.