This book explains the causes of dormancy, morphological, physiologicaland metabolic changes resulting from the decrease of chilling requirements in winter season, and its impact on bud break, growth, yield, fruit quality and some chemical constituents of buds. And also introduces some of the different methods used to break dormancy in tree buds and its effect on yield and fruit quality under the Egyptian conditions.

Name: Samir A. Seif El-Yazal Data of birth: 7/ 5/1952Place of birth: Fayoum, Egypt Nationality: Egyptian.Position: Professor of Horticulture Instiution: FayoumUniversity, Faculty of Agriculture,Horticulture Dept.Research Interests: Salinity, drought,Fruit breeding,water logginig, chiling,water relationships,fruitphysiology and dormancy.