微咸水灌溉对冬小麦光合及荧光动力学参数的影响

Effects of Brackish Water Irrigation on Photosynthetic Characteristics and Fluorescence Kinetics Parameters of Winter Wheat

以冬小麦为研究对象,通过设计不同微咸水浓度和不同灌水量的灌溉方案,采用桶栽试验,通过叶绿素含量、光响应曲线及荧光动力学参数的变化规律,探究微咸水灌溉下水盐胁迫对冬小麦的影响。结果表明:3 g/L的微咸水对叶绿素含量的影响较小,5 g/L的微咸水则会使得叶片叶绿素含量降低。在拔节期采用3 g/L的微咸水进行灌溉,可以促进冬小麦的生理生长,适当的盐分胁迫会促进作物的光合作用;盐分胁迫会改变作物对有效光辐射的利用方式,采用3 g/L的微咸水灌溉会促进冬小麦对低有效光辐射的利用效率。采用5 g/L的微咸水进行灌溉会影响冬小麦的叶片结构,降低叶片对高有效光辐射的响应,最终导致光合作用下降。另外,盐分胁迫会增加作物的初始荧光,使叶片的最大荧光产量降低,还会降低内禀光能转换效率。3 g/L的微咸水在可以一定程度上缓解作物的水分胁迫,并能增加作物在盐分胁迫下的生理生长。

In this paper,winter wheat was studied by designing irrigation schemes with different brackish water concentration and irrigation amount. The effects of water and salt stress on winter wheat under brackish water irrigation were studied by barrel cultivation experiment. The result show that: 3 g/L brackish water has less influence on chlorophyll content,while 5 g/L brackish water can decrease chlorophyll content in leaves;the physiological growth of winter wheat can be promoted by irrigation with 3 gL brackish water at jointing stage,and photosynthesis can be promoted by appropriate salt stress;salt stress can change the way crops use available light radiation;3 g/L brackish water irrigation can promote the utilization efficiency of low effective lightradiation in winter wheat;using 5 g/L brackish water for irrigation will affect the structure of the leaves of winter wheat,reduce the responses of the blades to high Efficient Optical radiation and lead to the decline of photosynthesis. In addition,salt stress can increase the initial fluorescence of crops,reduce the maximum fluorescence yield of leaves,and also reduce the intrinsic light energy conversion efficiency. The brackish water of 3 g/L can alleviate the water stress of crops to a certain extent and increase the physiological growth of crops under salt stress.