RT Journal Article SR Electronic T1 Deep Supercooling of Dormant and Deacclimating Vitis Buds JF American Journal of Enology and Viticulture JO Am J Enol Vitic. FD American Society for Enology and Viticulture SP 175 OP 177 DO 10.5344/ajev.1984.35.3.175 VO 35 IS 3 A1 Preston K. Andrews A1 C. R. Sandidge III A1 T. K. Toyama YR 1984 UL http://www.ajevonline.org/content/35/3/175.abstract AB Differential thermal analysis was used to measure deep supercooling in dormant buds of 15 Vitis vinifera L. cultivars, V. labruscana Bailey cv. Concord and four Vitis hybrids. The primary, secondary and tertiary buds in each compound bud produced discrete low temperature exotherms (LTE's). In singlebud experiments with White Riesling the largest LTE's originated from the primary buds. The temperature of the median low temperature exotherm (LTE50) increased about 11°C in White Riesling from late winter to early spring but increased 14°C in Concord and over 16°C in the French hybrid Chelois over the same period. These LTE50 increases are consistent with the characteristic deacclimation patterns of White Riesling and Concord buds. The LTE50 of White Riesling bud samples in late winter was within 1°C of the temperature which killed 50% of the buds under programmed freezing.