@article {Kliewer71, author = {W. M. Kliewer and Rodrigo E. Torres}, title = {Effect of Controlled Day and Night Temperatures on Grape Coloration}, volume = {23}, number = {2}, pages = {71--77}, year = {1972}, doi = {10.5344/ajev.1972.23.2.71}, publisher = {American Journal of Enology and Viticulture}, abstract = {Fruit coloration was investigated in several cultivars of Vitis vinifera L. grown in pots in sunlit phototron rooms held at various day and night temperatures. Mature {\textquoteright}Cardinal{\textquoteright}, {\textquoteright}Pinot noir{\textquoteright}, and {\textquoteright}Tokay{\textquoteright} fruits ripened at cool-day (15{\textdegree}C) and cool-night (15{\textdegree}C) temperatures had much greater coloration than fruits ripened at hot-day (35{\textdegree}C) and cool-night (15{\textdegree}C), hot-day (35{\textdegree}C) and warm-night (25{\textdegree}C), or cool-day (15{\textdegree}C) and warm-night (25{\textdegree}C) temperatures. Fruits grown at cool-day warm-night temperatures, however, had significantly greater levels of anthocyanins than fruits ripened at hot day temperatures, regardless of the night temperature. On the other hand, {\textquoteright}Cardinal{\textquoteright} and {\textquoteright}Pinot noir{\textquoteright} berries grown at hot-day (35{\textdegree}C) and warm-night (25 or 30{\textdegree}C) had a higher level of anthocyanins than fruit ripened at hot-day cool-night (15 or 10{\textdegree}C). A day temperature of 35{\textdegree}C completely inhibited anthocyanin synthesis in {\textquoteright}Tokay{\textquoteright} berries, regardless of night temperature. Also, a 30{\textdegree}C night temperature (day temperature 25{\textdegree}C) prevented anthocyanin formation in {\textquoteright}Tokay{\textquoteright} and greatly reduced the coloration of {\textquoteright}Cabernet Sauvignon{\textquoteright} compared with fruits ripened at 15 and 20{\textdegree}C night temperatures. On the basis of fruit coloration, {\textquoteright}Tokay{\textquoteright} was least tolerant to hot temperature, and {\textquoteright}Pinot noir, and {\textquoteright}Cabernet Sauvignon{\textquoteright} were most tolerant.}, issn = {0002-9254}, URL = {https://www.ajevonline.org/content/23/2/71}, eprint = {https://www.ajevonline.org/content/23/2/71.full.pdf}, journal = {American Journal of Enology and Viticulture} }