In order to study the soil moisture dynamics and irrigation regimes during the growth period of dwarfing apples in arid and saline-alkali areas, five irrigation treatments (W1: 0.6W3, W2: 0.8W3, W3: 22.5 mm, W4: 1.2W3, W5: 1.4W3) were set up in the southern Xinjiang region. A three-year (2019-2021) field plot experiment of dwarf apple in southern Xinjiang was carried out, and the HYDRUS-1D model was used to simulate the measured data of soil moisture. The root soil moisture transport pattern, root zone soil moisture stress, apple root water absorption capacity, and water deep percolation pattern were analyzed by numerical simulation to evaluate the model’s applicability to actual production in arid saline-alkali areas. Through the simulation analysis of 66 irrigation regimes, it was found that the simulated values of soil moisture content and nitrogen were in good agreement with the measured values, and the values of determination coefficient (R²), root mean square error (RMSE), and consistency index (d) were within a reasonable range. When the sum of soil water stress and deep percolation was between 19.81-21.11 mm, the water loss of farmland reached the minimum. Considering the optimal moisture dynamic analysis in the apple root zone, the recommended irrigation system was 19 times of irrigation, an irrigation quota of 27-36 mm, and an irrigation cycle of 6 d. Through the research results and model simulation, the theoretical basis can be provided for the optimization of irrigation system for dwarf rootstock apple in arid and saline-alkali areas.

Climate change has limited crop productivity worldwide. Understanding crop response to global climate changes is vital to maintaining agricultural sustainable development. A two-year experiment was conducted to investigate the effects of warming and drought on crop growth and winter wheat yield production. The results showed that both warming and drought shortened the crop growth period, reduced the leaf area index, and increased winter wheat biomass accumulation. Under sufficient water supply conditions, warming would increase photosynthetic and transpiration rates and water use efficiency, while under water deficit conditions, the opposite was observed. Under warming conditions, the grain yield of the water deficit treatment was 8.9% lower than that of the sufficient water supply treatment. Under non-warming conditions, the grain yield of water deficit treatment was 12.4% lower than that of the sufficient water supply. Under the conditions of water-sufficient supply, the grain yield of the warming treatment was 4.4% lower than that of the non-warming treatment, and under the conditions of water deficit, the grain yield of the warming treatment was 1.3% lower than that of the non-warming treatment. Warming tends to decrease wheat growth and grain yield, but sufficient water supply could improve winter wheat’s water use efficiency and reduce the warming limitation on wheat production.

Irrigation methods and nitrogen (N) fertilization modes have complicated impacts on wheat physiology, growth, and development, leading to the regulation of wheat grain yield and quality. However, the optimal water-N combination for drip-irrigated winter wheat remains unclear. A two-year field study was conducted to evaluate the influences of various N-fertigation and water regimes on wheat post-anthesis grain weight variation, yield, grain NPK content, and grain quality. The two irrigation quotas were I₄₅ (irrigation when crop evapotranspiration reduced by effective rainfall (ETa-P) reaches 45 mm) and I₃₀ (irrigation when ETa-P reaches 30 mm), while the six N application rates were N_0–100 (100% at jointing/booting), N_25–75 (25% at sowing and 75% at jointing/booting), N_50–50 (50% at sowing and 50% at jointing/booting), N_75–25 (75% at sowing and 25% at jointing/booting), N_100–0 (100% at sowing), and SRF₁₀₀ (100% of slow-release fertilizer at sowing). The experimental findings showed that post-anthesis grain weight variation, grain yield, grain NPK content, and grain quality were all markedly influenced by the various irrigation schedules and N-fertilization modes. The N_50–50 treatment was more beneficial for winter wheat post-anthesis grain weight variation than the N_100–0 and N_0–100 treatments under the two irrigation quotas and during the two seasons. The highest grain yields of 9.72 and 9.94 (t ha⁻¹) were obtained with the I₄₅N_50–50 treatment in 2020–2021 and 2021–2022, respectively. The grain crude protein was higher in the I₄₅SRF₁₀₀ treatment during the two seasons. The I₄₅N_100–0 combination significantly (P<0.05) enhanced the content of grain total starch by 7.30 and 8.23% compared with the I₄₅N_0–100 and I₃₀N_0–100 treatments, respectively, during the 2021–2021 season. The I₄₅N_100–0 treatment significantly (P<0.05) enhanced the content of grain total starch concentration by 7.77, 7.62 and 7.88% compared with the I₄₅N_0–100, I₃₀N_0–100, and I₃₀N_25–75 treatments, respectively, in the 2021–2022 season. The principal component analysis (PCA) indicated that the N_50–50 split N-fertigation mode could be the optimal choice for farmers during winter wheat production via drip irrigation.