CHILLING REQUIREMENTS OF APRICOT VARIETIES

The chilling requirements for breaking dormancy of several cultivars and new releases of apricot have been established. They ranged between approximately 600 and 1200 chill units or 40 to 65 “portions”, as an average of three consecutive years. In general, the variability for each variety over the three years studied was low although ‘Currot’, the variety with the lowest chilling requirements, showed a high variability with a variation coefficient of 15.5%. Both the Utah and “Portions” models for control of the breaking of rest appear equally adequate.