Abstract: Changes in carbohydrate contents and expression patterns of genes coding for alphaamylase，
beta-amylase and alpha-glucan phosphorylase in floral buds of‘Cuiguan’pear（Pyrus pyrifolia
Nakai）were studied during dormancy period for two successive years. The results indicated that the
content of soluble sugar in floral buds decreased gradually with increased depth of dormancy，and reached
the lowest value on November 15. Then the soluble sugar content increased during endo-dormancy and
dormancy release. The starch content in floral buds decreased with increased depth of dormancy. But there
is a difference in the occurring date of the lowest content of starch between two years. The starch content
increased gradually with the beginning of dormancy release，and reached maximum value just before totalrelease of dormancy and then decreased gradually. PpAMY，PpBAM1，PpBAM2 and PpPHS showed an
expression peak at the final stage of endo-dormancy and then dropped gradually until the total release of
dormancy. Thereafter，except for PpBAM2，other three genes up-expressed again. The change in the starch
content correlated with the expression levels of PpAMY，PpBAM1，PpBAM2 and PpPHS during the floral
buds dormancy of‘Cuiguan’pear，which implied that these genes possibly co-regulated carbohydrate
metabolism in floral buds of‘Cuiguan’pear

Key words: pear, dormancy, carbohydrate, gene expression