Abstract: In an experiment, pedicels of Lycopersicon esculenturm Mill. ‘Liaoyuanduoli’were used to study the changes of Ca²⁺ -ATPase activity, abscission rate and the activity of Endo-PG, PE, CMC-Na enzymes in abscission zone after the pedicelswere incubated in exogenous ethylene (20μL·L^-1 ). The results
showed that ethylene could accelerate the abscission during incubation, Ca²⁺ -ATPase activity first rose sharply and then declined quickly. Subsequently, there was a increase in the activity of Endo-PG, PE, CMC-Na enzyme in abscission zone. Calmodulin antagonist trifluoperizine (TFP) and Ca²⁺ chelator EGTA both inhibited the effects induced by ethylene to a certain extent. It is concluded that Ca²⁺ and CaM participate in the reaction of exogenous ethylene.

Key words: Tomato, Abscission, Ethylene, Hydrolysis enzyme, Calcium