| In order to explore the influence of different soil moisture, equivalent irrigation water and different nitrogen fertilizer configurations on the growth, output structure, photosynthesis properties, grain quality and water-nitrogen utilization efficiency of the two varieties, and provide theoretical basis and technical support for water-saving and high-output cultivation of winter-wheat, pool plant, pipe plant and the 15N tracer technique were carried out to perform a systematic study of these indicators under open-air and dry shed conditions.The main findings are as follows:1. Influence of different soil moisture on cultivation, grain source ratio and productionFrom setting stage to dough stage, we control the relative water content of soil from 50% to 80%. With the increase of soil water content, yield increases. The production of JiMai 20 increased by 180.9%, 42.23% and 12.67% respectively when 80% soil moisture is adopted compared to 50%, 60% and 70% soil moistures, while the production increased by 160.48%, 32.52% and 8.86% respectively for LuMai 21. It can be concluded that drought stress is generated when soil moisture is lower than 60%, and LuMai 21 has a better drought tolerance than JiMai 20. Increasing soil moisture is not only beneficial to increasing panicles per unit area, but also to the expansion of stem and green leaf area and the enhancement of photosynthesis in leaves growing on different stems. When soil moisture reaches 70%, chlorophyll content and photosynthetic rate in leaves on different stems are slightly different from those of 80% soil moisture. However, the decrement of soil water content can effectively improve the non-leaf organs in the proportion of the total green area and grain sources rate. But grain-leaf ratio at mature stage stabilizes at about 27 mg·cm-2, and grain source ratio stabilizes at about 11.5 mg·cm-2, which yields the highest production.2. Influence of different configurations of equivalent irrigation water on the output quality and water utilization efficiencyWhen total irrigation is controlled below 3600 kg·hm-2, with the increment of irrigation times, panicle per unit area, flour sedimentation value, wet gluten content and protein content of grains increase, but the economic output and protein output are the highest for T2. The economic output of JiMai20 increases by 15.55% and 7.93% compared with T1 and T3 respectively, while that of LuMai 21 increased by 12.40% and 13.95%. The impact of irrigation time on the amino acids varies with varieties. The content of essential amino acids and non-essential amino acids is highest to T2 treatment for Jimai20, while this value is highest to T3 treatment for Lumai21.Three treatments of water configuration have different influences on water utilization efficiency. For JiMai 20 and LuMai 21, water utilization efficiency in each treatment in 0-100cm soil layer changes from 14.60 kg·hm-2·mm-117.11 kg·hm-2·mm-1 and 15.22kg·hm-2·mm-117.53kg·hm-2·mm-1 respectively. Wherein, water utilization efficiency increases by 17.19%, 9.12% and 13.98%, 15.18% for T2 treatment, compared with T1 and T3 treatments respectively. In 0-200cm soil layer, water utilization efficiency increases by 21.42%, 16.63% and 18.02%, 23.08% for T2 treatment, compared with T1 and T3 treatments respectively.Total water consumption in different treatments mainly concentrated in the 0-100cm soil layer, which accounts for about 93.46% of total water consumption, and the 100-200cm layer only consumes 6.54% of total water consumption.3. Influence of different configurations of equivalent irrigation water on the photosynthesis performance and nitrogen accumulationDifferent configurations of equivalent irrigation water have influences on chlorophyl content of laminas growing on different caudexes, the photosynthesis rate and fluorescence parameters of flag leaves, as well as the antioxidant enzyme activity of flag leaves and top second leaves. T1 may lead to the rapid decrement of chlorophyl content of top second and top third leaves at late procreative stage. More irrigation times can extend the functional stage of laminas and prevent plants from premature senility, and T2 is proved to bring best advantages. Moreover, the general change trend of photosynthesis rate of flag leaves performs best when irrigating three times(T2). However, the trend varied randomly when the treatment is T1 or T3 due to different varieties. Irrigation configuration has little impact on fluorescence parameters at different stages, and the trend of the impact of irrigation configuration on the enzyme activity of SOD, POD and CAT is more or less the same as that of photosynthesis rate.Increasing irrigation times can promote single-stem nitrogen accumulation of JiMai 20 before flowering stage. But the nitrogen accumulation and transfer rate of mature stage grains are both present as T1>T2>T3, and transfer amount and contribution rate to grains present as T3>T2>T1. As for LuMai 21, nitrogen accumulation amount in vegetative organ at flowering stage behaves as T2>T3>T1, transfer amount T2>T1>T3, transfer rate T1>T2>T3, and contribution rate to grains T2>T3>T1.4. Influence of nitrogen application methods and irrigation configuration on outputOn the premise of the same total irrigation amount, irrigation three times at setting stage, flag leaf elongating stage and grouting stage, combined with 50%-bottom- dressing nitrogen application methods can achieve maximal economical output, biological output and total nitrogen uptake. On the other hand, On the premise of the same quantity of nitrogen fertilizer, open-air pipe cultivation of more total irrigation amount by 13.9% along with ground water supply can obtain 179.38% and 138.43% increment in economical and biological output respectively, compared with rainprotection shed-controlled pipe cultivation without ground water supply.5. Influence of nitrogen application methods and irrigation configuration on the efficiency of nitrogen absorption and utilizationFor wheat plant at mature stage, the proportion of absorbing different treatments are 28.24%～31.77% for NDFF and 66.90%71.76% for NDFS in the open air, and the proportion changes to 35.43%-38.84% for NDFF and 61.16%-64.36% for NDFS under rainprotection shed-controlled condition. The average values of six nitrogen utilization rates for different water-nitrogen configurations under open-air and rainprotection shed-controlled condition are 54.71% and 38.27% respectively, the values of residual rate are 32.23% and 29.48% respectively, and the values of loss rate are 13.06% and 32.25% respectively. Under open-air cultivation condition, nitrogen utilization rate increases by 42.96%, and loss rate decreases by 59.50%. Under the same cultivation conditions, nitrogen utilization rates increase by 11.70% and 10.06% for NDFF and NDFS respectively, , while loss rates decrease by 18.59% and 18.81%, if 50%-bottom-dressing nitrogen application method is adopted, compared with total-bottom dressing. Among different water configurations, nitrogen utilization rate is the highest when three water configuration treatment is adopted, which is higher than two water configuration treatment and four water configuration treatment, open-air condition by 10.75% and 38.43%, rainprotection shed-controlled by 19.74% and 37.44% respectively. At the same time, the residual rate and loss rate are lower than the other two treatments.Besides that, it is propitious to enhance nitrogen utilization rates and depress fertilizer loss rate if equivalent irrigation water is supplied by three times, combined with 50%-bottom-dressing nitrogen application method.
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