Subsoil tillage loosens compacted soil for better plant growth, but promotes water loss, which is a concern in areas that are commonly irrigated. Therefore, our objective was to determine the physiological responses of high yield spring maize (Zea mays L.) to subsoil tillage depth when grown in the Western plain irrigation area of Inner Mongolia, China. Our experiment during 2014 and 2015 used Zhengdan958 (Hybrid of Zheng58 × Chang7-2, produced by Henan academy of agricultural sciences of China, with the characteristics of tight plant type and high yield) and Xianyu335 (Hybrid of PH6WC × PH4CV, produced by Pioneer Corp of USA, with the characteristic of high yield and suitable of machine-harvesting) with three differing subsoil tillage depths (30, 40, or 50 cm) as the trial factor and shallow rotary tillage as a control. The results indicated that subsoil tillage increased shoot dry matter accumulation, leading to a greater shoot/root ratio. Subsoil tillage helped retain a greater leaf area index in each growth stage, increased the leaf area duration, net assimilation rate, and relative growth rate, and effectively delayed the aging of the blade. On average, compared with shallow rotary, the grain yields and water use efficiency increased by 0.7–8.9% and 1.93–18.49% in subsoil tillage treatment, respectively, resulting in the net income being increased by 2.24% to 6.97%. Additionally, the grain yield, water use efficiency, and net income were the highest under the treatment of a subsoil tillage depth of 50 cm. The results provided a theoretical basis for determining the suitable chiseling depth for high-yielding spring corn in the Western irrigation plains of Inner Mongolia.

Blackleg disease, caused by Plenodomus biglobosus, presents a significant global threat to production. This pathogen reduces both yield and crop quality in

Maize (Zea mays L.) is considered one of the most important grains in the world. Straw return and potassium fertilization can enhance the maize yield. Therefore, three field experiments were carried out in the three years (2018–2020) to study the effects of straw return at two methods and four levels of potassium fertilization on photosynthesis, dry matter accumulation and yield of the maize ‘Xianyu 335’. To conduct the field trials, a split plot system in five replications was established. Two straw return methods (straw return with deep tillage and straw mulching with no tillage) were in the main plots, and four potassium fertilization levels (0, 30, 45 and 60 kg/ha) were in the subplots. Each sub-plot consisted of 10 rows with 5 m length and 0.6 m width, and each sub-plot area was 30 m² in the three years. The results indicated that the straw return methods and the potassium supply significantly affected the maize photosynthesis, dry matter accumulation and yield in the three years. Under the same potassium supply, straw return with deep tillage significantly improved the maize photosynthesis, dry matter accumulation and yield compared to straw mulching with no tillage. The above characteristics improved with increased potassium supply. The treatment of SFK60 recorded the highest values for the parameters of maize photosynthesis, dry matter accumulation and yield during the three harvest seasons. The treatment of SFK45 reached maximum profit of maize planting, which was 12088.77 yuan/ha. Therefore, SFK45 was an effective way to ensure the stable and higher yields of maize and to maximize the income of farmers.

Maize (Zea mays L.) is a major cash and food crop in China and is critical to national food security. Straw returning improves soil physical properties by reducing bulk density and increasing porosity, while phosphate fertilization enhances soil P availability; their combined application can improve soil fertility and structure, creating favorable conditions for high yield. To evaluate this, we conducted a three-year field experiment (2023–2025) in the Tumochuan Plain irrigation area (Midwestern Inner Mongolia, China) with maize cultivar ‘Xianyu 335’. A control treatment (CK) without straw management and without phosphate fertilization was included for comparison. We examined the effects of two straw management practices (straw incorporation with deep tillage, SF; and surface straw mulching under no tillage, FG) and four phosphate fertilization rates (0, 80, 100, and 120 kg P₂O₅/ha) on photosynthetic characteristics, chlorophyll fluorescence, dry matter accumulation, and yield. S and P main effects were significant for all measured traits, including Fo; however, the S × P interaction was not significant for Fo, Fm, Fv/Fm, Ci, and yield. Compared with CK, all straw management treatments improved photosynthetic and chlorophyll fluorescence traits, increased dry matter accumulation, and enhanced grain yield. Straw incorporation with deep tillage consistently outperformed surface straw mulching under no tillage, and increasing phosphate fertilization rates enhanced the positive effects. Among the tested treatments and under the partial-budget assumptions, SFP120 (120 kg P₂O₅/ha) gave the highest yield (14,781.53 kg/ha), while SFP100 (100 kg P₂O₅/ha) had the numerically highest net profit (17,743.33 yuan/ha, ≈2546.17 USD/ha), 21.19 yuan/ha (≈3.04 USD/ha) above SFP120 (17,722.14 yuan/ha, ≈2543.15 USD/ha).