Abstract Improving both nitrogen utilization and peanut kernel quality (after removing peanuts shell) through water management is a growing concern for farmers. To explore the role of supplemental irrigation in nitrogen transformation between ‘source’ and ‘sink’, a split-plot experiment was conducted to evaluate the effects of water (rain-fed irrigation as IRI; supplemental irrigation as ISI) and nitrogen (0 kg∙ha―1 as N0; 40 kg∙ha―1 as N1; 60 kg∙ha―1 as N2 and 80 kg∙ha―1 as N3) coupling on soil nitrate nitrogen content, nitrogen accumulation and kernel quality of peanuts. We determined the dry matter weight per plant at peanut maturity as 64.66—74.92 g and 71.65—92.81 g for IRIN0 and ISIN3, respectively. ISIN2 significantly increased nitrogen accumulation, yield and water productivity. Furthermore, the ISI treatment prolonged the nitrogen uptake accumulation time of leaves, thus enhancing the nitrogen transfer from the leaves to the pods. Thus, the ISI treatment significantly increased the nitrogen harvest index by 2.13% and the nitrogen agronomic efficiency by 78.57% compared to the IRI treatment. In addition, the essential amino acid content in the fruits was within the range of 5.57—6.08%, while the content of non-essential amino acids was 16.43 to 17.46%. N1 was able to significantly increase the content of non-essential and essential amino acids, while ISI reduced the content of essential amino acids. Post-harvest soil nitrate nitrogen was principally distributed in the 0—40 cm soil layer, accounting for 77.75% of the 0—60 cm soil layer. Although the supplemental irrigation is associated with an increased risk of the nitrogen moving deeper into the soil, it greatly enhances nitrogen transfer from leaves to the pods at nitrogen application rates of 40—60 kg ha―1.

中文翻译：

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补充灌溉对施氮条件下花生水分和氮肥利用、产量和籽粒品质的影响

摘要 通过水管理提高氮的利用率和花生仁质量（去除花生壳后）是农民日益关注的问题。为了探索补充灌溉在“源”和“汇”之间氮转化中的作用，进行了裂区试验以评估水（雨育灌溉作为 IRI；补充灌溉作为 ISI）和氮（0 kg ∙ha-1 为 N0；40 kg∙ha-1 为 N1；60 kg∙ha-1 为 N2 和 80 kg∙ha-1 为 N3）对土壤硝态氮含量、氮积累和花生仁品质的耦合。我们确定花生成熟时每株植物的干物质重量分别为 64.66-74.92 g 和 71.65-92.81 g IRIN0 和 ISIN3。ISIN2 显着增加了氮积累、产量和水分生产力。此外，ISI处理延长了叶片对氮的吸收积累时间，从而促进了氮从叶片向豆荚的转移。因此，与 IRI 处理相比，ISI 处理显着增加了 2.13% 的氮收获指数和 78.57% 的氮农艺效率。此外，果实中必需氨基酸含量在5.57～6.08%之间，非必需氨基酸含量在16.43～17.46%之间。N1能够显着增加非必需和必需氨基酸的含量，而ISI降低必需氨基酸的含量。收获后土壤硝态氮主要分布在0—40 cm土层，占0—60 cm土层的77.75%。