The effects of growth regulators on the respiration metabolism of pear buds during dormant period were studied in this experiment. The results showed that, during early dormant period, the respiration intensity of pear buds was infirm and increased slowly. As the weather became very cold, the respiration intensity rapidly declined, and after that it changed a little. In the later stage of dormant period, the respiration intensity rose rapidly. The maximum value appeared on January 4th, at 0.390 mo1 O 2 $g -1 FW$min -1 , but thereafter declined to its original level. Under natural conditions, three respiratory pathways showed different changes. Pentose phosphate pathway might be the main reason for dormancy release in pear buds. The exogenous gibberellins were more efficient than salicylic acid in increasing the respiration rate. The exogenous SA appeared to play a more important role than exogenous GA 3 in phosphopentose pathway. The effect of gibberellins would be more effective than SA in tricarboxylic acid cycle (TCA). The respiration rate of glycolysis was not affected by gibberellins and salicylic acid.

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