Physio-ecological Responses Of Davidia Involucrate To Water-saving Measures

Using the design of quadratic regression general rotation including three factors, five levels, the basic models of efficiency were established between CaCl₂, SAC salicylic acid), hydrogel and synthetic value of drought resistance components of Davidia involucrate, and the quadratic regression models were simulated closely with reality by testing. The results of frequency analysis, successive order of different effecting factors, principal effects analysis, interactive effects analysis and physio-ecological responses of Davidia involucrate to water-saving measures indicated:(1) When the three factors of CaCl₂, SA, hydrogel were in the confidence limit of 95%, the optimal combination in cultivation and management for drought resistance of Davidia involucrate were as follows: 1106.700-1484.880 mg·L^-1 CaCl₂, 31.122 -54.115mg·L^-1 SA, and 434-604 ml·pot^-1 hydrogel (the first day) , 998.460-1391.820 mg·L^-1 CaCl₂,33.545-58.262 mg·L^-1 SA, and 485-638 ml·pot^-1 hydrogeKthe fifth day), 958.860-1368.720 mg·L^-1 CaCl₂, 41.510-67.253 mg·L^-1 SA, and 560-677 ml·pot^-1 hydrogel (the tenth day), 857.220-1302.720 mg·L^-1 CaCl₂, 41.962-69.265 mg·L^-1 SA, and 625-712 ml·pot^-1 hydrogel (the fifteen day) , 881.640-1311.300 mg·L^-1 CaCl₂, 42.865-68.280 mg·L^-1 SA, and 623-704 ml·pot^-1 hydrogel (the twenty day) . The test would be feasible and valuable to cultivation and management of the same climate, seedling age, soil condition. And it would be good guidance for the decision of water-saving measures in the introduction of Davidia involucrate and other garden plants.(2) The three factors of CaCl₂, SA, hydrogel revealed significantly positive effect on drought resistance of Davidia involucrate. Impacting synthetic value of drought resistance components of Davidia involucrate, the orders of the three factors were as follows: SA > CaCl₂ > hydrogel (the first day) , SA > CaCl₂ > hydrogel (the fifth day) , SA > hydrogel > CaCl₂ (the tenth day), hydrogel > SA > CaCl₂ (the fifteen day), hydrogel > SA > CaCl₂(the twenty day) . CaCl₂ and SA increased soil water use at the initial of water stress. Hydrogel had readily-released to maintain higher soil water content to improve higher...