Wang Chao, Cui Haixing, Jin Min, Wang Jiayu, Li Chunhui, Luo Yongli, Li Yong, Wang Zhenlin
Wheat Breeding State Key Laboratory, Shandong Agricultural University, Taian 271000, China.
College of Agronomy, Shandong Agricultural University, Taian 271000, China.
Plants (Basel). 2025 Jan 18;14(2):277. doi: 10.3390/plants14020277.
Optimizing nitrogen (N) sources has the potential to improve wheat tillering, nitrogen use efficiency (NUE), and grain yield, yet the underlying mechanisms remain unclear. This study hypothesizes that combining specific N sources can increase zeatin riboside + zeatin (ZR + ZT) content in tiller nodes and maintain a higher ZR + ZT/gibberellin A7 (GA) ratio, thereby promoting tiller development, enhancing NUE, and increasing yield. The effects of N source treatments on two wheat cultivars, the multi-spike Shannong 28 (SN28) and the large-spike Tainong 18 (TN18), were investigated. A total of seven N treatments were tested: no nitrogen (N0), urea (N1), calcium nitrate (N2), ammonium chloride (N3), and equal doses of urea and calcium nitrate (N4), urea and ammonium chloride (N5), and calcium nitrate and ammonium chloride (N6). The results showed that treatment N4 significantly increased the levels of ZR and ZT in tiller nodes, while maintaining a higher ZR + ZT to GA ratio. This hormonal shift promoted tiller formation and biomass accumulation. Under N4, both cultivars exhibited the highest number of effective spikes and biomass in higher-order tillers. N4 also enhanced N accumulation in the grains, N absorption efficiency, and N translocation, while reducing N loss. Compared to N1, effective spike numbers increased by 7.8% in SN28 and 5.6% in TN18, resulting in a 6.4% increase in grain yield for SN28 and a 2.2% increase for TN18. In conclusion, the combined application of urea and calcium nitrate optimizes hormonal regulation, improves NUE, and significantly enhances wheat tillering and grain yield, providing a promising strategy for enhancing wheat productivity.
优化氮源有潜力提高小麦分蘖、氮素利用效率（NUE）和籽粒产量，但其潜在机制仍不清楚。本研究假设，特定氮源组合可增加分蘖节中玉米素核苷 + 玉米素（ZR + ZT）含量，并维持较高的ZR + ZT/赤霉素A7（GA）比值，从而促进分蘖发育、提高氮素利用效率并增加产量。研究了氮源处理对两个小麦品种的影响，多穗型品种山农28（SN28）和大穗型品种泰农18（TN18）。共测试了七种氮处理：不施氮（N0）、尿素（N1）、硝酸钙（N2）、氯化铵（N3），以及等量的尿素和硝酸钙（N4）、尿素和氯化铵（N5）、硝酸钙和氯化铵（N6）。结果表明，N4处理显著提高了分蘖节中ZR和ZT的水平，同时维持了较高的ZR + ZT与GA的比值。这种激素变化促进了分蘖形成和生物量积累。在N4处理下，两个品种在高阶分蘖中均表现出最高的有效穗数和生物量。N4还提高了籽粒中的氮积累、氮吸收效率和氮转运，同时减少了氮损失。与N1相比，SN28的有效穗数增加了7.8%，TN18增加了5.6%，SN28的籽粒产量提高了6.4%，TN18提高了2.2%。总之，尿素和硝酸钙的联合施用优化了激素调节，提高了氮素利用效率，并显著增强了小麦分蘖和籽粒产量，为提高小麦生产力提供了一种有前景的策略。
