Abstract: In order to investigate the pattern of fruits energy transfer in adverse conditions, the changes of of H⁺ -ATPase activities and Ca²⁺ -ATPase activities of ‘Ya' pear fruit in low temperature and pathogen stress were tested with luciferase fluorensece and molybdenum blue spectrophotometry. The results showed that the postharvest storage at low temperature for 0～60 d caused ATP contents decreased and the H⁺ -ATPase activity markedly increased. The peak of Ca²⁺ -ATPase activity was delayed and the value was higher in comparison with that stored at normal temperature. ATP contents of the inoculated fruit with Physalospora piricola were significantly lower than that of the healthy one in 60 h after inoculation. The activity of H⁺ -ATPase was higher than that in healthy one, the value was highest at 36h after inoculated. The activity of Ca²⁺ -ATPase declined and the decline rate was faster than control. It was suggested that adversity stress used abundant energy, H⁺ -ATPase could modulate pulp cell pH level and organic acid concentration, and high activity of Ca²⁺-ATPase could postpone the ripening and senescence.

Key words: Ya' pear, ATP, H⁺-ATPase, Ca²⁺-ATPase