Effects Of Soil Amendments On Corn Yield And Physiological And Biochemical Indexes Under Drought Stress

Due to the low precipitation in the semi-arid area of Northeast China,the uneven distribution of precipitation,and the frequent high temperature,the drought disaster is serious,and the drought seriously affects the growth and development of maize in various periods.In this experiment,the saline-alkali soil in the semi-arid area of Northeast China was used as the test soil.Through the design of pot experiment,4 water gradients were set:W₁（greater than 80%of the field water holding capacity）,W₂（70%-80%of the field water holding capacity）,W₃（60%-70%of the field water holding capacity）,W₄（50%-60%of the field water holding capacity）,to determine the effect of different drought stress levels on the growth period of maize under the conditions of soil with and without soil amendment The purpose is to explore the changes of agronomic traits,physiological indexes and yield of maize in different growth periods under different drought stress levels,as well as the actual application effect of adding soil amendments.It is a semi-arid environment in Northeast China.Provide a theoretical basis for the implementation of corn water control,drought resistance and disaster reduction.Research indicates:（1）In each growth period of maize,with the increase of drought stress,maize soil water content,field water holding capacity,and saturated water content gradually decrease;maize plant height,stem thickness,and dry matter accumulation gradually decrease;maize leaf photosynthetic rate and stomata Conductivity,transpiration rate,chlorophyll content,water consumption and water use efficiency gradually decreased;the MDA content,Pro content,SOD,POD and CAT activities of corn leaves gradually increased.At the same time,the above-mentioned traits and indicators will not significantly decrease and increase in the water range of W₁ to W₂;the water range of W₂ to W₃ will slowly decrease and increase;the water range of W₃ to W₄ and below W₄will decrease and increase significantly.（2）Under the same degree of drought stress,the maize soil water content,photosynthetic rate,stomata conductance,transpiration rate and chlorophyll content of maize leaves after rewatering are all increased to a certain extent compared with those in drought;The field water holding capacity and saturated water content of maize soil did not change significantly compared with those in drought;the MDA content,Pro content,SOD,POD and CAT activities of maize leaves after rewatering were all reduced to a certain extent compared with those in drought.At the same time,the magnitude of decrease and increase is generally expressed as W₃>W₂>W₄.（3）Adding soil amendments can effectively alleviate the reduction of maize soil water content,field water holding capacity,saturated water content,maize leaf photosynthetic rate,stomatal conductance,transpiration rate,and chlorophyll content under drought stress,while effectively increasing SOD,POD and CAT activity,alleviating the accumulation of MDA and Pro,reducing water consumption during the growth period of maize and improving water use efficiency,thereby effectively increasing yield.