研究添加不同增效剂组合的磷酸二铵（DAP）肥料对红壤中玉米根系形态、磷素吸收利用效率及产量的影响，设置不施磷（CK）、常规DAP（T1）、施用添加黄腐酸+聚谷氨酸DAP（T2）、添加黄腐酸+海藻酸DAP（T3）、添加黄腐酸+鼠李糖脂DAP（T4）、添加聚谷氨酸+泛菌多糖DAP（T5）以及添加聚谷氨酸+壳寡糖DAP（T6）处理的2个田间试验。结果表明:相比于T1处理，T3和T6处理可显著促进根系生长，成熟期根表面积、根长和根体积较T1提高33.2%～66.8%、31.9%～87.1%、16.9%～74.4%；根尖数、分叉数和交叉数提升15.8%～80.4%、16.0%～74.2%、20.2%～97.1%。T3和T6处理在大喇叭口期与成熟期均显著促进玉米磷素积累，磷素吸收效率与磷肥利用率较T1处理分别提高35.6%～53.1%和134.4%～360.8%（P <0.05）。结构方程模型分析表明，添加增效剂处理可通过促进根体积和根表面积进而提高根、茎的磷吸收量，最终显著提高产量。因此，DAP肥料中添加黄腐酸和海藻酸或添加聚谷氨酸和壳寡糖可促进玉米根系发育与磷素积累，从而实现增产。

Two field experiments were conducted to investigate the effects of different combinations of enhancers added to diammonium phosphate (DAP) fertilizer on the root morphology, phosphorus absorption and utilization efficiency, and yield of corn in red soil. The treatments included no phosphorus application (CK), conventional DAP (T1), DAP added with fulvic acid + polyglutamic acid (T2), DAP added with fulvic acid + alginic acid (T3), DAP added with fulvic acid + rhamnolipid (T4), DAP added with polyglutamic acid + fructan (T5), and DAP added with polyglutamic acid + chitosan oligosaccharide (T6). The results showed that compared with T1, T3 and T6 significantly promoted root growth. At maturity, the root surface area, root length and root volume of T3 and T6 were increased by 33.2% to 66.8%, 31.9% to 87.1%, and 16.9% to 74.4% respectively compared with T1. The number of root tips, forks and intersections increased by 15.8% to 80.4%, 16.0% to 74.2%, and 20.2% to 97.1% respectively. T3 and T6 significantly promoted phosphorus accumulation in corn at the large trumpet stage and maturity. The phosphorus absorption efficiency and phosphorus fertilizer utilization rate were increased by 35.6% to 53.1% and 134.4% to 360.8% respectively compared with T1 (P < 0.05). Structural equation model analysis indicated that the addition of enhancers could promote phosphorus absorption in roots and stems by increasing root volume and root surface area, and ultimately significantly increase yield. Therefore, the addition of fulvic acid and alginic acid or polyglutamic acid and chitosan oligosaccharide to DAP fertilizer can promote root development and phosphorus accumulation in corn, thereby achieving increased yield.

国家自然科学(3236180247)､云南省基础研究专项(202401AT070215)､云南省农业联合专项(202301BD070001-101)､云天化DAP增效田间试验技术服务项目(2024)