Abstract Applying saline water resources for irrigating croplands requires serious attentions when sustainable agriculture is considered. A two-year field investigation was carried out in a drip-irrigated sunflower field under six irrigation treatments, including (i) full freshwater irrigation (FI), full irrigation with diluted seawater (DS) (SI), alternate DS-freshwater irrigation (FSI), freshwater-PRD (partial root-zone drying) irrigation with 25 % less water than full (PRD1), DS-PRD irrigation with 25 % less water than full (PRD2), alternate DS-freshwater irrigation under PRD with 25 % less water than full (PRD3), in three replicates. Compared to the FI treatment, crop yield was reduced by 3.1–32 %, with the lowest one under PRD1. Among the DS treatments, PRD3, resulted in the highest grain yield (4306 kg ha−1), grain nitrogen content (2.83 %), oil yield (1907 kg ha−1) and irrigation water productivity (1.10). PRD3 also saved freshwater by 20 %, and kept soil salinity of the rooting-zone below the maximum crop tolerance threshold. Based on the results, PRD3 might be a cost-effective pathway which guarantees the sustainable application of diluted seawater in the irrigated sunflower lands.

中文翻译：

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整合部分根区干燥和盐水灌溉以维持淡水稀缺地区的向日葵生产

摘要 在考虑可持续农业时，利用咸水资源灌溉农田需要认真考虑。在滴灌向日葵田中进行了为期两年的田间调查，采用六种灌溉处理，包括（i）全淡水灌溉（FI）、稀释海水全灌溉（DS）（SI）、交替 DS-淡水灌溉（ FSI)，淡水-PRD（部分根区干燥）灌溉，用水量比满水少 25%（PRD1），DS-PRD 灌溉，比满水少 25%（PRD2），替代 DS-珠三角下的淡水灌溉，用水量比满水少 25%水少于满 (PRD3)，三个重复。与 FI 处理相比，作物产量降低了 3.1-32%，PRD1 下产量最低。在 DS 处理中，PRD3 导致最高的谷物产量（4306 kg ha-1）、谷物氮含量（2.83 %）、油产量（1907 kg ha-1）和灌溉水生产力（1.10）。PRD3 还节省了 20% 的淡水，并将生根区的土壤盐分保持在作物最大耐受阈值以下。根据结果​​，PRD3 可能是一种经济高效的途径，可保证稀释海水在向日葵灌溉地中的可持续应用。