TY - JOUR T1 - Preveraison Leaf Removal Changes Fruit Zone Microclimate and Phenolics in Cold Climate Interspecific Hybrid Grapes Grown under Cool Climate Conditions JF - American Journal of Enology and Viticulture JO - Am J Enol Vitic. DO - 10.5344/ajev.2019.18052 SP - ajev.2019.18052 AU - Jacob Scharfetter AU - Beth Ann Workmaster AU - Amaya Atucha Y1 - 2019/03/19 UR - http://www.ajevonline.org/content/early/2019/03/14/ajev.2019.18052.abstract N2 - Changes in grape cluster microclimate during ripening have been extensively exploredacross V. vinifera cultivars, but there is limited information about its effect on cold climateinterspecific hybrid grape (CCIHG) cultivars grown under cool climate conditions. The influenceof a single preveraison leaf and lateral shoot removal (“exposed”) treatment on fruit zonemicroclimate and juice total phenolic concentration (TPC), monomeric anthocyanin concentration (MAC), and percent polymeric color was evaluated in the white cultivars Brianna and La Crescent and the red cultivars Frontenac, Marquette, and Petite Pearl over three consecutive growing seasons and their respective wines in the last year of the study. Treatment effect on juice TPC in the white cultivars was cultivar dependent and there was no detectable treatment effect on wine TPC. For the red cultivars, Frontenac, Marquette, and Petite Pearl, the exposed treatment increased the TPC, MAC, and increased the percent polymeric color in the wines. The beneficial influence of the exposed treatment on MAC, TPC, percent polymeric color, and titratable acidity was associated with an increase in berry temperature and an increase in photosynthetically active radiation in the fruiting zone. The cultural practice of a single, preveraison leaf and lateral shoot removal may be an effective strategy to improve red wine color stability of CCIHG cultivars grown under cool climate conditions. ER -