Study On The Physiological Mechanism Of Water Saving,high Quality And High Yield Of Wheat In Hetao Irrigation Area

Aiming at the current situation of water shortage in the Hetao Plain Irrigation Area of Inner Mongolia,with the goal of improving the quality of wheat grains and increasing the yield,the local wheat variety Yongliang No.4 was used as the test material,and a full growth period was set for two consecutive growing seasons from 2020 to 2021.No irrigation(CK),1 water(1W)from tiller to joint,2 water from tiller to joint+heading to flowering(2W),and 3 water from tiller to joint+heading to flowering+grain filling(3W).Systematically study the differences in growth and development,photosynthetic characteristics,material accumulation and transport,yield and quality,and water use of wheat,as well as the dynamic changes of protein accumulation in various grain components,clarify the relationship between irrigation amount and grain quality,yield and water use efficiency,and determine The water-saving,high-quality,and high-yield irrigation system for wheat provides a basis for establishing a water-saving,high-quality,and high-yield cultivation technology system for wheat in Hetao Irrigation Area,Inner Mongolia.The main findings are as follows:(1)With the increase of irrigation times,the economic yield and its components of wheat showed an increasing trend,and the total water consumption in the whole growth period also increased accordingly,but the water use efficiency(WUE)decreased significantly.The WUE of 2W treatment was significantly higher than that of 3W treatment by 16.7%～23.5%.Irrigation 2 water treatment(2W)realizes the relative unity of high yield and high water efficiency.(2)With the increase of irrigation times,the plant height and upper leaf area of wheat increased,the leaf area index before heading increased rapidly,and decreased relatively slowly after flowering.From flowering to maturity,the SPAD value,Fv/FM value,piabs value and photosynthetic rate of flag leaves in 2W and 3W treatments were higher and decreased relatively slowly.2W treatment improved canopy illumination and promoted population dry matter accumulation and grain filling at grain filling stage.Reduce irrigation properly(1W,2W treatment)to promote the transport of stored substances in wheat vegetative organs to grains and improve their contribution to grains.(3)During wheat grain development,the starch content increased in an"s"curve,and the starch content of grain increased significantly with the increase of irrigation.Properly reducing the number of irrigation(1W,2W)is beneficial to improve the content of grain protein,wet gluten,sedimentation value and flour yield,especially to increase the content of metabolic protein and storage protein in wheat.Under the treatment of no irrigation in the whole growth period(CK)or irrigation in the filling period(3W),the total protein content of wheat grain and the protein content of each component decreased.(4)Wheat grain yield and starch content were significantly positively correlated with leaf area index,dry matter accumulation,total storage matter in leaves and storage matter transport before spikelet and spike,and significantly negatively correlated with total storage matter transport and transport rate in stems and sheaths.Grain protein content had a very significant positive correlation with the total storage material transport capacity,transport rate and contribution rate of spikelets and spikelets,and the storage material transport capacity and contribution rate after anthesis.Taking reasonable irrigation measures,maintaining high photosynthetic area and population dry matter accumulation during grain filling,and promoting the transport of nutrient organs,especially spikelet storage materials,can significantly improve grain protein content.(5)The comprehensive analysis shows that the water consumption range of water-saving wheat with high quality,high yield and high efficiency in Hetao irrigation area is 3057～3350 m~3/hm~2.The water-saving irrigation mode of tillering to jointing+heading to flowering irrigation can realize the coordination and unity of water-saving,high quality and high yield of wheat.