Su Dandan, Zhang Hengjia, Teng Anguo, Zhang Changlong, Lei Lian, Ba Yuchun, Zhou Chenli, Li Fuqiang, Chen Xietian, Wang Zeyi
College of Agriculture and Biology, Liaocheng University, Liaocheng, China.
College of Water Conservancy and Hydropower Engineering, Gansu Agricultural University, Lanzhou, China.
Front Plant Sci. 2024 Oct 16;15:1451350. doi: 10.3389/fpls.2024.1451350. eCollection 2024.
The pervasively imprudent practices of irrigation and nitrogen (N) application within Oasis Cool Irrigation zones have led to significant soil nitrogen loss and a marked decrease in water and nitrogen use efficiency.
To address this concern, a comprehensive field experiment was conducted from April to September in 2023 to investigate the impact of varying degrees of water and fertilization regulation strategies on pivotal parameters including potato yield, quality, nitrogen balance, and water-nitrogen use efficiency. The experimental design incorporated two water deficit degrees at potato seedling (W1, 55%-65% of Field Capacity (FC); W2, 45%-55% of FC), and four distinct nitrogen application gradients (N0, 0 kg ha-1 of N; N1, 130 kg ha-1 of N; N2, 185 kg ha-1 of N; N3, 240 kg ha-1 of N). A control was also included, comprising N0 nitrogen application and full irrigation (W0, 65%-75% of FC), totally eight treatments and one check.
The results indicated that the tuber yield, plant dry matter accumulation, plant height, plant stem, and leaf area index increased with higher nitrogen fertilizer application and irrigation volume. However, tuber starch content, vitamin C, and protein content initially increased and then decreased, while reducing sugar content consistently decreased. Except for W1N2 treatment, the irrigation water use efficiency increased as the N application rate rose, while the nitrogen partial factor productivity, crop nitrogen use efficiency and soil nitrogen use efficiency decreased with an increase in N fertilizer application. The W1N2 treatment resulted in a higher yield (43.16 t ha-1), highest crop nitrogen use efficiency (0.95) and systematic nitrogen use efficiency (0.72),while maintaining moderate levels of soil nitrate and ammonium nitrogen.
Therefore, through the construction of an integrated evaluation index (IEI), the W1N2 treatment of mild water deficit (55%-65% of FC) at potato seedling combined with the medium nitrogen application (185 kg ha-1 of N) has the highest IEI (0.978), it was recommended as the optimal water-nitrogen regulation and management strategies to facilitate high-yield, high-efficiency, and environmentally sustainable potato production in the cold and arid oasis areas of northwest China.
绿洲冷灌区普遍存在的不合理灌溉和施氮做法导致了大量土壤氮素流失，以及水分和氮素利用效率显著下降。
为解决这一问题，于2023年4月至9月开展了一项全面的田间试验，以研究不同程度的水分和施肥调控策略对马铃薯产量、品质、氮素平衡以及水氮利用效率等关键参数的影响。试验设计包括马铃薯苗期的两个水分亏缺程度（W1，田间持水量的55%-65%；W2，田间持水量的45%-55%），以及四个不同的施氮梯度（N0，0 kg·ha-1氮；N1，130 kg·ha-1氮；N2，185 kg·ha-1氮；N3，240 kg·ha-1氮）。还设置了一个对照，即不施氮（N0）且充分灌溉（W0，田间持水量的65%-75%），共计八个处理和一个对照。
结果表明，块茎产量、植株干物质积累、株高、茎粗和叶面积指数随着氮肥施用量和灌溉量的增加而增加。然而，块茎淀粉含量、维生素C和蛋白质含量先增加后降低，而还原糖含量持续降低。除W1N2处理外，灌溉水利用效率随着施氮量的增加而提高，而氮肥偏生产力、作物氮素利用效率和土壤氮素利用效率随着氮肥施用量的增加而降低。W1N2处理产量较高（43.16 t·ha-1），作物氮素利用效率最高（0.95），系统氮素利用效率最高（0.72），同时土壤硝态氮和铵态氮保持在适度水平。
因此，通过构建综合评价指数（IEI），马铃薯苗期轻度水分亏缺（田间持水量的55%-65%）结合中等施氮量（185 kg·ha-1氮）的W1N2处理具有最高的IEI（0.978），建议将其作为最佳水氮调控管理策略，以促进中国西北寒冷干旱绿洲地区马铃薯的高产、高效和环境可持续生产。
