Comparison of phenotypic methodologies to characterize chilling and heat requirements of peach and apple cultivars
A three-year study was conducted on several peach and apple cultivars respectively in order to compare two phenotyping protocols that aimed at determining the date of endodormancy break: the Tabuenca test and the single-node cutting test. The date of endodormancy release is a crucial parameter since it allows estimating the chilling and heat requirements for fruit tree flowering. The Tabuenca test was conducted during three years for 8 peach cultivars ('Sunred', 'Mayglo', 'Minastar', 'Tasty Free', 'Flavorcrest', 'Summergrand', 'Jalousia' and 'Fantasia'). The single-cutting node test was applied for two years on cultivars 'Jalousia' and 'Sunred'. For apple, both tests were applied during two years for cultivars 'Golden Delicious', 'Gala' and 'Granny Smith'. As a conclusion, for areas with insufficient chilling, it is recommended to use the single-cutting test on vegetative buds by focusing on the ATB (average time to budbreak) variable in order to select genotypes with low values during the period of forcing. On the other hand, for regions with higher heat requirement (to avoid spring frost risk), it is recommended to work on floral buds with the Tabuenca test in order to estimate precisely the dates of dormancy break and to select genotypes with higher sums of heat units.
Lalanne-Tisné, G., Quero-García, J., Lafargue, M., Joly, J., Fouilhaux, L., Dirlewanger, E., Costes, E. and Legave, J.M. 2017. Comparison of phenotypic methodologies to characterize chilling and heat requirements of peach and apple cultivars. Acta Hort. (ISHS) 1172:349-354
dormancy, Tabuenca test, single-node cutting test, climate change