Maize is one of the most widely used plants in the agricultural industry, and the fields of application of this plant are broad. The experiment was conducted at the Látókép Crop Production Experimental Station of the University of Debrecen, Hungary. Three mid-ripening maize hybrids with different FAO numbers were used in the present study. The effects of different nitrogen supplies were examined as a variable rate of abiotic stress and the interrelationship among the essential nutrients through the nutrient acquisition and partitioning of the different vegetative and generative plant parts. The results showed that NPK application compared to the control treatment (no fertilizer application) increased DM in all tissues of maize, while increasing nitrogen application from 120 to 300 kg ha⁻¹ had no significant effect on this trait. The highest protein content was obtained with the nitrogen application of 120 kg ha⁻¹, and the higher nitrogen fertilizer application had no significant effect on this trait. Seeds and leaves had a maximum zinc and manganese value in terms of nitrogen content (protein). Dry matter was positively correlated with nitrogen, potassium, and manganese content, while the dry matter had a negative correlation with nickel content. In general, to achieve a maximum quantitative and qualitative yield, it is recommended to use NPK fertilizer with a rate of 120 kg ha⁻¹ N for maize cultivation.

Shortage of fresh water and drought stress are important factors limiting crop productivity in semi-arid and arid regions. Irrigation management needs to be optimised to improve irrigation water-use efficiency (IWUE), and thus, agricultural sustainability in these climates. A field experiment was conducted at two semi-arid locations in Iran to evaluate the impact of irrigation regime (applied after crop evapotranspiration of 70 mm (I70), 100 mm (I100) or 130 mm (I130)) and irrigation method (applied to every furrow (EFI) or variable alternate furrow (AFI)) on yield and IWUE of maize (Zea mays L.). Yield response to irrigation rate was quadratic. Kernel yield was 8476 kg ha–1 under I70, and this reduced by 12.3% under I100 and 27.7% under I130. Yield reduction due to water stress was attributed to decline in both kernel number and kernel weight. Implementation of AFI resulted in a significant saving in irrigation water. At I70, 31% less water was used with AFI than with EFI. Irrigation water saving was even greater under I100 and I130 when AFI was implemented. Regardless of irrigation regime, IWUE under AFI was always greater than under EFI (1.32 vs 1.03 kg m–3 for grain and 3.30 vs 2.47 kg m–3 for biomass production). In addition, plants were shorter with a longer root system under AFI, and the role of carbohydrate remobilisation in kernel filling was greater under AFI consistently among irrigation regimes. The results indicated good potential of AFI for development of water-saving strategies for maize production in semi-arid climates.

To evaluate the herbage yield and silage quality of sorghum as affected by nitrogen and irrigation levels, a 2-yr experiment (2017–2018) was conducted in a semi-arid region of Iran. Three irrigation levels (supply 100, 75, and 50% of soil moisture deficit as I₁₀₀, I₇₅, I₅₀) and three nitrogen levels (150, 300, and 450 kg urea ha⁻¹ as N₁₅₀, N₃₀₀, N₄₅₀) were evaluated. Increasing nitrogen levels increased green herbage yield (GHY), irrigation water use efficiency (IWUE), lactic acid (LA), propionic acid (PA), digestible organic matter (DOM), crude protein (CP), and metabolizable energy (ME) but reduced the pH, dry matter content (DMC), neutral detergent fiber (NDF), and acid detergent fiber (ADF) of silage. The I₁₀₀ compared to I₅₀ treatment, resulted in higher GHY (69%), ADF (4%), NDF (2%), DMC (5%), ash (4%), and LA (13%) but reduced the IWUE (14%), CP (15%), DOM (3%), GP (4%), and ME (3%). Overall, the I₇₅× N₄₅₀ can be considered as the suitable treatment for sorghum silage production in semi-arid regions by saving 24% of irrigation water and producing high GHY (117.52 Mg ha⁻¹) with the maximum IWUE (23.64 kg m⁻³) and high content of CP (88.5 g kg⁻¹) and PA (0.34 g kg⁻¹). In conclusion, the I₇₅× N₄₅₀ is introduced as the superior treatment; however, in conditions of severe limitation of water resources, it is recommended to irrigate silage sorghum with the supply of 50% soil moisture deficit with the application of 150 kg urea ha⁻¹ (I₅₀× N₁₅₀).

To evaluate the forage yield and quality of Berseem and Persian clover cultivars, a two-year experiment was conducted during two growing seasons (2017–2018 and 2018–2019). Irrigation was the main factor, including full irrigation (I₁₀₀), moderately limited (I₇₅), and severely limited irrigation (I₅₀). The sub-factor consisted of ten cultivars of clover, five of which were Persian clover (Pars, Aleshtar, Eghlid, Harat, and Zabol) and five cultivars of Berseem clover (Karaj, Elite, Ekinaton, Vienna, and Alex). The results showed that the highest dry matter (DM) and crude protein (CP) yield under all irrigation levels were obtained from the Berseem clover cultivars. Imposing limited irrigation reduced the DM yield, digestible dry matter (DDM) yield and content, CP yield, dry matter intake (DMI), and relative feed value (RFV) of forage, whereas the content of CP, water-soluble carbohydrates (WSC), neutral detergent fiber (NDF), and acid detergent fiber (ADF) increased. Irrigation water use efficiency (IWUE) for DM, DDM, and CP yield under limited irrigation were also increased. Comparison of two groups of Persian and Berseem clover cultivars also showed that with increasing drought stress intensity, in Berseem cultivars, DM yield, DDM yield and content, and RFV decrease was higher. Increasing IWUE under limited irrigation was higher in Persian cultivars for DM and DDM yield. Overall, Berseem clover had higher forage yield and water use efficiency in all irrigation regimes, and the forage quality of this species showed more sensitivity to drought. Abbreviations :I₁₀₀, I₇₅, and I₅₀, full, moderately limited, and severely limited irrigation (equivalent to 100, 75, and 50% weekly evaporation and crop water requirement, respectively); DM, dry matter; CP, crude protein; ADF, acid detergent fiber; NDF, neutral detergent fiber; DDM: digestible dry matter; WSC, water-soluble carbohydrates; DMI, dry matter intake; RFV, relative feed value; IWUE, irrigation water use efficiency.

Water scarcity is a major obstacle to forage crop production in arid and semi-arid regions. In order to improve food security in these areas, it is imperative to employ suitable irrigation management techniques and identify drought-tolerant cultivars. A 2-year field experiment (2019–2020) was conducted in a semi-arid region of Iran to assess the impact of different irrigation methods and water deficit stress on forage sorghum cultivars’ yield, quality, and irrigation water-use efficiency (IWUE). The experiment involved two irrigation methods, i.e., drip (DRIP) and furrow (FURW), and three irrigation regimes supplied 100% (I₁₀₀), 75% (I₇₅), and 50% (I₅₀) of the soil moisture deficit. In addition, two forage sorghum cultivars (hybrid Speedfeed and open-pollinated cultivar Pegah) were evaluated. This study revealed that the highest dry matter yield (27.24 Mg ha⁻¹) was obtained under I₁₀₀ × DRIP, whereas the maximum relative feed value (98.63%) was achieved under I₅₀ × FURW. Using DRIP resulted in higher forage yield and IWUE compared to FURW, and the superiority of DRIP over FURW increased with the severity of the water deficit. The principal component analysis indicated that, as drought stress severity increased across all irrigation methods and cultivars, forage yield decreased, while quality increased. Plant height and leaf-to-stem ratio were found to be suitable indicators for comparing forage yield and quality, respectively, and they showed a negative correlation between the quality and quantity of forage. DRIP improved forage quality under I₁₀₀ and I₇₅, while FURW exhibited a better feed value under the I₅₀ regime. Altogether, in order to achieve the best possible forage yield and quality while minimizing water usage, it is recommended to grow the Pegah cultivar and compensate for 75% of soil moisture deficiency using drip irrigation.