TY - JOUR T1 - Influence of Light Intensity and Growth Regulators on Fruit-Set and Ovule Fertilization in Grape Cultivars under Low Temperature Conditions JF - American Journal of Enology and Viticulture JO - Am J Enol Vitic. SP - 163 LP - 167 DO - 10.5344/ajev.1976.27.4.163 VL - 27 IS - 4 AU - Kalliopi A. Roubelakis AU - W. M. Kliewer Y1 - 1976/01/01 UR - http://www.ajevonline.org/content/27/4/163.abstract N2 - The percentages of berries set and ovules fertilized per cluster, and berry development, were studied in five Vitis vinifera L. cultivars grown in a phytotron room under day/night temperatures of 15/10°C and average light intensities of 2680, 750, and 480 ft-c. Benzyladenine (BA) and 2-(chloroethyl) trimethylammonium chloride (CCC) were applied to vines grown at the two lower light levels. There was no fruit-set at 480 ft-c in any cultivar, but at 750 ft-c some set occurred in Carignane. All cultivars set berries at 2680 ft-c, ranging from 13% (White Riesling) to 31% (Pinot noir). The percentage ovules fertilized per cluster ranged from 0% (French Colombard) to 5.1% (Pinot noir). Percentage fruit-set and ovule fertilization at 2680 ft-c were about 3- and 8-fold greater, respectively, than at 750 ft-c. Neither BA nor CCC significantly improved fruit-set at 750 or 480 ft-c compared to nonhormone-treated vines; however, both reduced the number of fertilized ovules. Berry weight of seedless Carignane fruits treated with BA was about 6-fold greater than that of control fruits (no hormone), whereas CCC had no effect on berry weight. ER -