Studies on Impacts of Water Stress-rehydration Responses of Winter Wheat on Its Yield WUE
|School||Chinese Academy of Agricultural Sciences|
|Keywords||Winter Wheat Water use efficiency Drought Identification and evaluation|
Water shortages are the main factors restricting China's grain production, in engineered water saving maximum effectiveness, only vigorously develop to improve crop water use efficiency biological water-saving technologies, in order to achieve new breakthroughs in water-saving agriculture. Wheat is one of the main food crops in China, to strengthen the influencing factors on water use efficiency of wheat establish methods and techniques for rapid identification of the varieties of drought resistance and water system, wheat drought resistance and water breeding and identification of the key. Select six different water use efficiency of winter wheat varieties the rain shed potted plant growing trials, six varieties of winter wheat jointing - booting and filling - maturity sufficient water supply and water deficit conditions, yield and yield WUE differences, and analyzes the different growth stages of different the Drought mechanism type, different level WUE and drought - restoring force after rehydration yield WUE determine yield WUE key influencing factors, and to explore suitable for mass variety of water-saving traits identified reliable physiological indicators. The results show that: (1) according to the drought resistance (output indicators) and water conservation (yield WUE indicators), winter wheat varieties can be divided into four drought resistance and water types, water saving and drought: Jinmai 47 Luohan 2 , Zhengmai 9023; Drought is not a water-saving: Trititrigia 20; drought-resistant water-saving the Weak type: Yumai 18; weak type of water-saving strong drought resistance: Shijiazhuang No. 8. (2) the impact of different types of drought-resistant mechanism of production WUE. Jointing - booting stage under water deficit conditions, membrane ion leakage rate and yield WUE good correlation (R2 = 0.4099), and the correlation is weak enough both under water conditions; varieties osmotic adjustment ability and production WUE not significant; stomatal conductance and transpiration rate and yield WUE was highly significant correlation. Enough water conditions, stomatal conductance and yield WUE correlation coefficient R2 = 0.7841, reached a very significant level. The grouting - mature enough water, and drought stress conditions, the Drought indicators and yield WUE correlation did not reach a significant level. (3) different levels of correlation analysis showed that WUE and yield WUE, jointing - booting stage, enough water conditions, the intrinsic WUE, leaf WUE. Stage biomass, stage of aboveground biomass and stage aboveground biomass WUE and yield WUE related is reached significant levels, including the highest intrinsic WUE (R2 = 0.7138). Intrinsic WUE under water deficit conditions, stage of biological amount the stage ground biomass and the phase of the ground biomass WUE and yield WUE reached a very significant with correlation, which between intrinsic WUE and stage ground biological amount WUE of the highest, R2, respectively, for 0.6602 and 0.6445. The grouting - mature, enough water and water deficit conditions, each level WUE and yield WUE below jointing - booting stage. (4) jointing - booting stage of drought - rehydration, Luohan 2, Jinmai 47 Yumai 18 and Shijiazhuang No. 8 and the restoring force is strong, the weak recovery in Yan Mak 20, and Zhengmai 9023. Transpiration rate, membrane ion leakage rates, higher stomatal conductance and intrinsic WUE and yield, R2 respectively 0.8471,0.7782,0.7586 and 0.5904, but the correlation of these traits and yield WUE did not reach a significant level. Jointing - booting stage production WUE identification of suitable period. Jointing - booting stage, enough water under the conditions of stomatal conductance and intrinsic WUE as yield WUE preliminary identification of indicators; under water deficit conditions, stomatal conductance, intrinsic WUE, aboveground biomass (WUE), transpiration rate and membrane ion leakage rate WUE preliminary identification of indicators can be used as production. Drought rehydration after restoring force is an important factor affecting the variety yield, and thus provide new ideas for the evaluation of yield WUE.