Abstract:The mitigation effects of exogenous Ca2+ on waterlogginginduced damages to agronomic and physiological indexes of pepper cultivar Bolahongniu were investigated by spraying Ca2+ on leaves surface at different days. The results showed that: (1) the biomass, seedling index, chorophyll contents, root activity, proline, soluble sugar, SOD and CAT activities of pepper seedlings showed a trend of increasing firstly, then decreasing with spraying days increase. MDA content showed a trend of decreasing firstly, then increasing with spraying days increase. (2) Spraying calcium one day treatment(T1d) showed no significant mitigation effect under waterlogging damage for pepper. Spraying calcium 3 days treatment(T3d) and spraying calcium 6 day treatment(T6d) showed the increased mitigation effect gradually. Spraying calcium 9 days treatment(T9d) achieved the best results, while the mitigation effect gradually weakened with spraying calcium 12 days treatment(T12d) and spraying calcium 20 days treatment(T20d), but still significantly better than that of T1d treatment. Overall, the results suggested that Ca2+ might mitigates waterlogginginduced damages to pepper and achieves better alleviation effects by spraying 9 days.