ABSTRACT

Nitrogen and water should be applied at the right time and amount to obtain optimum crop yield in arid and semi-arid regions. The study was carried out in 2017–2018 to investigate the effects of different supplementary irrigation levels applied after harvests, and different nitrogen sources on water use efficiency (WUE), yield and quality characteristics of sun-cured tobacco. The study included five different nitrogen sources (N₁: zero-nitrogen, N₂: ammonium nitrate, N₃: ammonium sulfate, N₄: calcium ammonium nitrate, and N₅: urea) and four different irrigation treatments (I₀:No irrigation; I₃₃:66% deficit, I₆₆:33% deficit and I₁₀₀:100% full irrigation). The effects of nitrogen sources and supplementary irrigation treatments on plant height, leaf number, leaf width, leaf height, yield, quality grade, sugars, nicotine, phenolics, WUE and irrigation water use efficiency (IWUE) were statistically significant. Seasonal crop evapotranspiration values ranged between 117.7 and 235.3 mm. The highest WUE 1.65 kg m⁻³ and IWUE: 10.48 kg m⁻³ were recorded in I₃₃ treatment. Plant characteristics were different between nitrogen sources; however, the results did not indicate a prominent nitrogen form. The results for supplementary irrigation revealed that the I₁₀₀ treatment in semi-arid conditions increased the sun-cured tobacco yield by 22% with acceptable quality improvements. The gross income increased 1705 $ ha⁻¹ with the increase in tobacco yield and sale price per hectare.

摘要

在干旱和半干旱地区，应适时施肥、施肥，以使作物获得最佳产量。该研究于 2017-2018 年进行，旨在调查收获后不同补充灌溉水平和不同氮源对晒烟水分利用效率 (WUE)、产量和质量特性的影响。该研究包括五种不同的氮源（N ₁：零氮，N ₂：硝酸铵，N ₃：硫酸铵，N ₄：硝酸钙铵和 N ₅：尿素）和四种不同的灌溉处理（I ₀：否灌溉；I ₃₃ :66% 赤字，I ₆₆ :33% 赤字和 I₁₀₀ :100% 完全灌溉）。氮源和补充灌溉处理对株高、叶数、叶宽、叶高、产量、品质等级、糖分、尼古丁、酚类、WUE和灌溉用水效率（IWUE）的影响具有统计学意义。季节性作物蒸散值介于 117.7 和 235.3 毫米之间。_{在I 33}处理中记录了最高的WUE 1.65 kg m ^-3和IWUE：10.48 kg m ^{-3 。}不同氮源的植物特性不同；然而，结果并未表明存在显着的氮形式。补充灌溉的结果表明，I ₁₀₀半干旱条件下的处理使晒烟产量提高了 22%，质量改善也令人满意。随着烟草产量和每公顷销售价格的增加，总收入增加了 1705 $ ha ^{-1 。}