文献类型： 外文期刊

作者： Zhang, Yongli ¹ ; Ni, Kang ¹ ; Yang, Xiangde ¹ ; Long, Lizhi ² ; Ma, Lifeng ¹ ; Su, Youjian ² ; Ruan, Jianyun ¹ ;

作者机构： 1.Chinese Acad Agr Sci, Tea Res Inst, Key Lab Biol Genet & Breeding Special Econ Anim &, Minist Agr & Rural Affairs, Hangzhou 310008, Peoples R China

2.Anhui Acad Agr Sci, Tea Res Inst, Hefei 230031, Peoples R China

3.Chinese Acad Agr Sci, Grad Sch, Beijing 100081, Peoples R China

4.Xihu Natl Agr Expt Stn Soil Qual, Hangzhou 310008, Peoples R China

关键词： nitrogen fertilizer; timing effect; N-15 tracing; tea cultivar; nitrogen uptake; thermal condition

期刊名称：AGRONOMY-BASEL （ 影响因子：3.4； 五年影响因子：3.8 ）

ISSN：

年卷期： 2025 年 15 卷 5 期

页码：

收录情况： SCI

摘要： Applying a top dressing of nitrogen fertilizer before harvesting spring tea is vital for producing high-quality spring tea. However, the interaction between the sprouting phenological characteristics of various cultivars and the timing of top dressing remains unclear. A field trial was conducted to investigate such interaction. Urea enriched with N-15 was applied to soil of the early-sprouting cultivar Jia-ming-1 (JM1) and the late-sprouting cultivar Tie-guan-yin (TGY) on 29 January (early application, EApp) or 10 March (late application, LApp), respectively. The bud density and yield of young spring shoots were significantly decreased in LApp compared to EApp. Such differences were more remarkable in the early-sprouting cultivar (JM1) than in the late-sprouting cultivar (TGY). The N-dff (N derived from N-15-enriched urea) in mature leaves and young spring shoots as well as the amount of N-15 in young spring shoots were all higher in EApp than in LApp. N-dff in both mature leaves (R-2 = 0.99, p < 0.001) and young spring shoots (R-2 = 0.61-0.89, p < 0.01) could be well predicted by the growing degree days of the duration between the N fertilization and sampling. N-dff and N-15 concentrations in mature leaves were significantly correlated with the content of nitrate and the ratio of ammonium to total inorganic nitrogen. Partial least squares path modeling revealed that thermal condition directly affected soil N supply and soil pH and thereby affected N-dff in mature leaves and young spring shoots. Our findings highlight the importance of early pre-spring topdressing of N fertilizer to improve the yield and N use efficiency of spring tea in both early- and late-sprouting tea cultivars. The work identified a synergistic effect of N uptake by tea plants, N transformation, and soil pH related to the thermo-conditions of early and late N topdressing.