Abstract:Taking rotary tillage combined with border irrigation as the control (CK), the effects of different tillage methods, including autumn subsoiling (QS35) and summer subsoiling (XS35) under border irrigation, and different irrigation methods, including autumn subsoiling with border irrigation (QS35), autumn subsoiling with microspray irrigation (QS35SI) and autumn subsoiling with drip irrigation (QS35DI), on photosynthetic characteristics of maize were studied to determine the rational irrigation methods under subsoiling. The results showed that the LAI, chlorophyll relative content, net photosynthetic rate, stomatal conductance, intercellular CO2 concentration, transpiration rate and yield of QS35 were 20.7%, 6.4%, 17.8%, 36.9%, 40.1%, 18.9%, 9.6% higher than CK under different tillage modes, respectively. There were no significant differences in Fv/Fm before and after anthesis, the qP, ETR, Y(Ⅱ) before and after an thesis were QS35>XS35>CK, while NPQ was QS352 concentration, transpiration rate and yield of QS35 SI treatment were 23.8%, 11.2%, 37.9%, 69.1%, 79.2%, 38.7%, 7.5% higher than CK, respectively. There were no significant differences in Fv/Fm before and after flowering, the qP, ETR, Y(Ⅱ) before and after flowering were QS35 SI > QS35 DI > QS35 > CK, while NPQ was QS35 SI