Effects Of Irrigation Period On Water Consumption Characteristics And Nitrogen Accumulation And Transportation Of Winter Wheat

The experiment was conducted in Shenfeng village,Taigu District,Shanxi Province from 2018 to 2020.In a randomized block design,8 treatments were set in 2018-2019,i.e.no irrigation in whole growth period(CK),overwintering water(Wo),jointing water(Wj),booting water(Wb),overwintering + jointing water(Wo+j),overwintering + booting water(Wo+b),jointing + booting water(Wj+b)and overwintering + jointing + booting water(Wo+j+b),and 4 treatments were set in 2019-2020,i.e.no irrigation in whole growth period(CK),overwintering water(Wo),booting water(Wb),and overwintering + booting water(Wo+b).The effects of different irrigation period combinations on the growth and development,water and nitrogen use efficiency and grain protein of winter wheat were studied in order to provide a theoretical basis for water-saving,highquality and high-yield irrigation of shuidi wheat in Jinzhong.The main results were as follows:(1)In 2018-2019,overwintering water was beneficial to the development of wheat plant and the total stem number of wheat population.The yield of wheat in Wo+j+b treatment was the highest,followed by Wo+b treatment.The yield components were as follows: overwintering water increased spike number per unit area,jointing water increased grain number per spike,booting water increased 1000-grain weight.In 2019-2020,the total number of stems in anthesis to maturation stages of Wo and Wo+b treatments were higher than other treatment.The yield,spike number,grain number per spike and 1000-grain weight of Wo+b treatment were the highest.(2)Overwintering water was beneficial to wheat to use the deep soil water.In 2018-2019,the water consumption of Wo+b and Wj+b treatments from irrigation and precipitation accounted for 32.09%-33.35% and 44.84%-46.61%,respectively.In 2019-2020,the proportion of water consumption of Wo+b treatment from irrigation,precipitation and soil water storage was about 3: 4: 3.With the increase of irrigation amount,water use efficiency increased first and then decreased.In two years,Wo+b treatment could obtain higher water use efficiency,irrigation use efficiency and irrigation benefit.(3)In 2018-2019,Wo+b treatment promoted nitrogen transport before anthesis and nitrogen accumulation after anthesis,and simultaneously obtained higher nitrogen uptake efficiency,nitrogen partial productivity and nitrogen use efficiency.In 2019-2020,the above indexes of Wo+b treatment were higher.Compared with CK,the irrigation treatment significantly increased protein yield.In 2018-2019,the protein yield of Wo+b and Wo+j+b treatments increased by 52.41% and 64.45%,respectively.In 2019-2020,the protein yield of Wo+b treatment was the highest(increased by 569.88%).Compared with CK,the irrigation treatment decreased the content of grain protein and its components,and Wo+b treatment could obtain higher content of grain protein and its components.In conclusion,under the experimental conditions,overwintering + booting water treatment can promote wheat growth and development,promote nitrogen transport before anthesis and nitrogen accumulation after anthesis,and obtain higher water and nitrogen use efficiency,grain yield and protein content,which is a better irrigation combination for local water saving,quality improvement and efficiency enhancement.