Li Jiaqi, Li Jingyi, Sun Hao, Li Xin, Sun Lei, Li Wei
College of Resources and Environment, Northeast Agricultural University, Harbin 150030, China.
Key Laboratory of Germplasm Enhancement, Physiology and Ecology of Food Crops in Cold Region, Northeast Agricultural University, Ministry of Education, Harbin 150030, China.
Plants (Basel). 2025 Jul 14;14(14):2171. doi: 10.3390/plants14142171.
Potato ( L.) is a chlorine-sensitive crop. When soil Cl concentrations exceed optimal thresholds, the yield and quality of potatoes are limited. Consequently, chloride-containing fertilizers are rarely used in actual agricultural production. Therefore, two years of field experiments under natural rainfall regimes with three chlorine application levels (37.5 kg ha/20 mg kg, 75 kg ha/40 mg kg, and 112.5 kg ha/60 mg kg) were conducted to investigate the leaching characteristics of Cl in field soils with two typical textures for Northeast China (loam and sandy loam soils). In this study, the reliability of Cl residual estimation models across different soil types was evaluated, providing critical references for safe chlorine-containing fertilizer application in rain-fed potato production systems in Northeast China. The results indicated that the leaching efficiency of Cl was significantly positively correlated with both the rainfall amount and the chlorine application rate ( < 0.01). The Cl migration rate in sandy loam soil was significantly greater than that in loam soil. However, the influence of soil texture on the Cl leaching efficiency was only observed at lower rainfall levels. When the rainfall level exceeded 270 mm, the Cl content in all the soil layers became independent of the rainfall amount, soil texture, and chlorine application rate. Under rain-fed conditions, KCl application at 80-250 kg ha did not induce Cl accumulation in the primary potato root zone (15-30 cm), suggesting a low risk of toxicity. In loam soil, the safe application range for KCl was determined to be 115-164 kg ha, while in sandy loam soil, the safe KCl application range was 214-237 kg ha. Furthermore, a predictive model for estimating Cl residuals in loam and sandy loam soils was validated on the basis of rainfall amount, soil clay content, and chlorine application rate. The model validation results demonstrated an exceptional goodness-of-fit between the predicted and measured values, with R > 0.9 and NRMSE < 0.1, providing science-based recommendations for Cl-containing fertilizer application to chlorine-sensitive crops, supporting both agronomic performance and environmental sustainability in rain-fed systems.
马铃薯（L.）是一种对氯敏感的作物。当土壤氯浓度超过最佳阈值时，马铃薯的产量和品质会受到限制。因此，在实际农业生产中很少使用含氯化肥。为此，开展了为期两年的田间试验，在自然降雨条件下设置了三个氯施用量水平（37.5千克/公顷/20毫克/千克、75千克/公顷/40毫克/千克和112.5千克/公顷/60毫克/千克），以研究中国东北两种典型质地土壤（壤土和砂壤土）中氯的淋溶特征。本研究评估了不同土壤类型中氯残留估算模型的可靠性，为中国东北雨养马铃薯生产系统中安全施用含氯化肥提供了关键参考。结果表明，氯的淋溶效率与降雨量和氯施用量均呈显著正相关（<0.01）。砂壤土中氯的迁移速率显著高于壤土。然而，仅在较低降雨水平下观察到土壤质地对氯淋溶效率的影响。当降雨水平超过270毫米时，所有土层中的氯含量与降雨量、土壤质地和氯施用量无关。在雨养条件下，施用80 - 250千克/公顷的氯化钾不会导致马铃薯主要根区（15 - 30厘米）氯积累，表明毒性风险较低。在壤土中，氯化钾的安全施用量范围确定为115 - 164千克/公顷，而在砂壤土中，氯化钾的安全施用量范围为214 - 237千克/公顷。此外，基于降雨量、土壤粘粒含量和氯施用量，验证了壤土和砂壤土中氯残留的预测模型。模型验证结果表明预测值与实测值之间具有出色的拟合度，R>0.9且NRMSE<0.1，为对氯敏感作物施用含氯化肥提供了基于科学的建议，支持雨养系统中的农艺性能和环境可持续性。
