Study On Water-saving Irrigation Scheduling Of Millet Under Film Drip Irrigation

Aiming at the problems of low single industrial benefit,serious shortage of water resources and low utilization rate of water resources in Hongsipu District,taking drip irrigation of millet under film as the research object,carry out field test in Hongsibao Town,Hongsibao District,Wuzhong City,Ningxia Hui Autonomous Region.Through the research on physiological growth index and yield and quality index of millet,establish irrigation system suitable for local conditions in the current year,explore the appropriate leaf area index and its change rule,study on temporal and spatial variability of soil moisture distribution in millet root zone along the direction of drip irrigation belt,the main conclusions are:(1)Set three Water quota gradients 300,225,150m3/hm2(T1-T3).The overall soil moisture content decreases with the decrease of irrigation quota.With the passage of time,the farther away from the emitter,the more significant the change of water content and the faster the decrease to the deep soil.The spatiotemporal variation of soil water content shows that T2 has the largest spatiotemporal variability,and T3 has the smallest spatiotemporal variability,the spatiotemporal variation of soil water content in three irrigation treatments is in the middle range of variability.Therefore,the dispersion degree of soil water under three irrigation quotas is appropriate.(2)Through equation fitting,it can be seen that as the irrigation quota increases,the plant height will first decrease and then increase.Increasing the number of irrigation cycles has an increasing effect on the plant height of millet;Increasing the irrigation quota to a certain extent will reduce the number of tillers in millet,and as the irrigation frequency increases,the number of tillers in millet will first decrease and then increase;The number of leaves decreases first and then increases with the increase of irrigation quota and irrigation frequency;The irrigation quota plays an increasing role in the ear length of millet,which first increases and then decreases with the increase of irrigation frequency.The yield of grain and grass decreases first and then increases with the increase of irrigation quota and irrigation frequency;The yield of millet increases with the increase of irrigation quota,and decreases first and then increases with the increase of irrigation frequency;The total yield decreases first and then increases with the increase of irrigation quota and irrigation frequency;The carbohydrate content first increases and then decreases with the increase of irrigation quota,and then decreases with the increase of irrigation frequency;The dietary fiber content increases with the increase of irrigation quota,and the dietary fiber content first increases and then decreases with the increase of irrigation frequency.(3)Set five irrigation quota gradients and three irrigation frequency gradients,use the entropy weight method and scoring mechanism to study the suitable irrigation system.The top three irrigation systems in the overall score are J150,B150 and J110 respectively(3.03,2.83,2.81),and the score difference is not big.J150 treatment should be selected as the local irrigation system under the condition of abundant water resources and complete facilities;J110 treatment is selected as the local irrigation system in case of lack of water resources and incomplete conditions and facilities.(4)The conversion coefficients of leaf area corresponding to jointing and tillering stage,jointing and booting stage,heading stage and filling maturity stage are 1.42,1.50,1.53 and 1.50.The area index of millet cotyledon in the whole experimental area at different growth stages showed a trend of gradual increase and a trend of gradual decrease with the passage of time.The best leaf area index of millet should be about 6,and the leaf area index at the filling maturity stage is 6.96,which is relatively good.The relevant research results provide a certain reference basis for the research on water-saving irrigation system of millet under film drip irrigation,improving water use efficiency,saving water resources and increasing millet yield in the arid area of central Ningxia.