Variations in the chilling requirements for breaking leaf bud endodormancy in wild pear species and pear cultivars

Abstract

Seasonal changes in percent budbreak were determined to estimate the chilling requirement for breaking leaf bud endodormancy in wild pear species and pear cultivars. Pyrus fauriei Schneid. had the lowest chilling requirement among the wild pear species examined; P. aromatica Nakai and P. communis L. had the highest. Among the major Japanese pear cultivars, 'Hosui' had the lowest chilling requirement, followed by 'Kosui', 'Nijisseiki', 'Niitaka', 'Shinsetsu', and 'Shinsui'.