The contribution of wastewater irrigation with the improvement of irrigation practices to the productivity of silage maize is a priority issue to investigate considering the saving of scarce freshwater resources and the necessity to dispose wastewater. The aim of this study was to evaluate the effect of different irrigation levels (L100, L67 and L33) of recycled municipal wastewater (RW) compared to freshwater (FW) using subsurface drip (SSDI), surface drip (SDI) and furrow irrigation (FI) methods on yield and some physiological traits of silage maize in semi-arid conditions at a high altitude. When the total daily reference evapotranspiration value reached 50 ± 5 mm, irrigation quantities corresponding to 100%, 67% and 33% of soil moisture deficit based on field capacity in fully irrigated plots with freshwater were applied in different irrigation levels. Crop actual evapotranspiration (ETa) values were found close in both water types. SSDI reduced ETa by 18.5% and 45.6% in L100 level, 15.2% and 38.9% in L67, and 11.6% and 32.6% in L33, respectively compared to SDI and FI. The highest fresh biomass yield was determined in the SSDI-RW-L100 combination as 77.55 t ha^-1, and resulted in 5% and 12.9% higher values than in SDI and FI. Leaf relative chlorophyll and water contents, leaf area index and electrolyte leakage showed strong linear correlations with yield and evapotranspiration values. The highest water productivity was determined in the SSDI-RW-L100 combination as 21.48 kg m^-3 and it was higher by 28.2% and 99.4% than those in SDI and FI, respectively. Improvement of productivity with increased irrigation quantities in SSDI delivered the high yield response factor of 1.70–1.77. Therefore, it is concluded that the SSDI method can be a successful practice to improve productivity by alleviating the need for water for silage maize especially under full irrigation with RW.

考虑到稀缺淡水资源的节约和废水处理的必要性，废水灌溉与灌溉方法的改进对青贮玉米生产力的贡献是优先研究的问题。本研究的目的是评估不同灌溉水平（L100、L67 和 L33）的循环城市废水（RW）与使用地下滴灌（SSDI）、地表滴灌（SDI）和沟灌的淡水（FW）相比的影响。 FI) 高海拔半干旱条件下青贮玉米产量和一些生理性状的方法。当日总参考蒸发量达到 50±5 mm 时，灌溉量对应 100%，67% 和 33% 的基于田间容量的土壤水分亏缺在用淡水充分灌溉的地块中应用于不同的灌溉水平。两种水体的作物实际蒸散量 (ETa) 值接近。与 SDI 和 FI 相比，SSDI 在 L100 水平上分别降低了 18.5% 和 45.6%，在 L67 中降低了 15.2% 和 38.9%，在 L33 中分别降低了 11.6% 和 32.6%。SSDI-RW-L100 组合的最高新鲜生物质产量为 77.55 吨公顷^-1，导致值比 SDI 和 FI 高 5% 和 12.9%。叶相对叶绿素和水分含量、叶面积指数和电解质泄漏与产量和蒸散值呈强线性相关性。SSDI-RW-L100 组合的最高产水量为 21.48 kg m ^-3，分别比 SDI 和 FI 高 28.2% 和 99.4%。随着 SSDI 中灌溉量的增加，生产力的提高提供了 1.70-1.77 的高产量响应因子。因此，得出的结论是，SSDI 方法可以通过减轻青贮玉米对水的需求，特别是在使用 RW 充分灌溉的情况下，成为提高生产力的成功实践。