| Hebei Province is an important wheat production area which has an important strategic position in ensuring national food security.In view of the prominent contradiction between supply and demand of water resources and low nitrogen use efficiency in this area,this experiment studied the effects of micro-spraying water and fertilizer integrated nitrogen topdressing on yield and water and nitrogen use efficiency with traditional border irrigation as control,in order to provide theoretical basis for water-saving and high-yield and high-quality cultivation of wheat.The experiment was conducted in the Gaocheng district of Shijiazhuang City,Hebei Province from 2020 to 2022.A two-factor split plot experiment was set up in the field.The varieties were strong gluten variety Gaoyou 2018(GY2018)and medium gluten variety Heng 4399(H4399).There were four methods of irrgation and fertilization which were traditional border irrigation with nitrogen topdressing at jointing stage(I1),integrated jointing stage of water and fertilizer(I2),1:1 topdressing of nitrogen at jointing stage and anthesis stage(I3)and topdressing of nitrogen at jointing stage,anthesis stage and 12 days after anthesis with a ratio of 5:3:2(14).The main research results are as follows:1.I4 treatment obtained the highest grain yield,which was the optimal treatment in this experiment.Compared with I1,I2 and I3 treatments,the grain yield of L.sinensis of GY2018 was 3.38%to 21.51%higher and that of L.sinensis H4399 was 2.92%to 18.30%higher.The grain weight increased significantly with the grain filling rate,ultimate growth and active filling period in the middle and late grouting period.The 1000-grain weight of GY2018 was 3.98%～9.10%higher and that of H4399 was 3.82%～10.26%higher.2.I4 treatment is beneficial to maintain the interception rate of highlight energy,improve photosynthetic capacity,promote post-flowering dry matter accumulation and transport to seeds,and lay a material foundation for high yield.In both cultivars,LAI,SPAD value,PAR interception rate,Pn,PS Ⅱ and Fv/Fm of flag leaves under I4 treatment were significantly higher than those under other treatments.The dry matter accumulation at maturity stage was 1.78%～10.88%higher than other treatments,and the transfer volume of vegetative organs to grains after flowering was the highest.3.High water consumption mode coefficient from flowering to maturity and high water storage consumption in subsoil were the characteristics of I4 treatment to obtain high yield and high water use efficiency.I4 treatment significantly increased the total water consumption,soil storage water consumption and its proportion to the total water consumption.The water storage consumption in the soil layer of 40～160 cm at maturity stage was significantly higher than that in other treatments.Compared with I1,I2 and I3 treatments,the water consumption from flowering to maturity,average daily water consumption and water consumption modulus were 51.54%,67.13%and 57.25%higher.The water use efficiency of I2 and I3 treatments was the highest,followed by I1 treatment.4.I4 treatment promoted the transport of storage nitrogen from vegetative organs to grains,increased nitrogen harvest index,increased grain protein content and grain alcohol ratio,and improved grain quality.For the two cultivars,I4 treatment significantly increased grain nitrogen accumulation at maturity,and the transfer and contribution rate of nitrogen from vegetative organs to grain were 32.37%and 18.82%higher than other treatments.The nitrogen absorption efficiency was I4.81%,4.64%and 5.08%higher than that of I1,I2 and I3 treatments,respectively.The nitrogen harvest index was I4>I2、I3>I1;I4 treatment significantly increased grain protein content,grain alcohol ratio,wet gluten content and gluten index and its dough formation time and dough stabilization time were also the highest.I4 treatment significantly increased the bread volume and bread score of GY 2018,while I2,I3 and I4 treatment of H 4399 showed no significant difference.In conclusion,I4 treatment can improve wheat’s absorption and utilization of soil water storage,enhance the photosynthetic capacity in the middle and late stages of grout filling,promote the accumulation and transport of dry matter and nitrogen after anthesis,improve water and nitrogen utilization efficiency,thus obtain the highest grain yield and improve grain quality.I4 is the best irrigation and fertilization method under the conditions of this experiment.The above results can provide theoretical basis and technical support for the improvement of winter wheat yield and the application of micro-jet irrigation technology. |
PDF Full Text Request