明确新疆灰枣不同生育期配施尿素硝酸铵钙叶面肥对果实形态、品质及产量的影响，为红枣的科学施肥和品质提升提供理论依据和实践指导。以喷施清水为对照，分别于花期、幼果期、果实膨大前期和后期设置 5个喷施 2 g/kg尿素硝酸铵钙溶液处理，测定果实纵径、横径、硬度、可溶性固形物含量、 Vc含量、可滴定酸含量及产量等指标。结果表明，鲜枣在果实膨大后期喷施 2 g/kg尿素硝酸铵钙叶面肥溶液时，单果重 11.15 g、产量 11 183.0 kg/hm2、可溶性固形物含量 378.5 g/kg、Vc含量 3 815. 0 mg/kg均为最高，分别较喷施清水对照提高了 5.49%、50.52%、23.46%、33.55%；可滴定酸含量最低，为 0.9 g/kg，较喷施清水对照降低 53.57%。干枣在果实膨大前期喷施 2 g/kg尿素硝酸铵钙叶面肥溶液时果实硬度最高，为 17.46 Pa，较喷施清水对照提升 29.72%(P < 0.01)。相关性分析表明，可溶性固形物含量、果实硬度和果实横纵径与干枣果实产量间的相关性均达到显著水平( P < 0.05)。多元回归模型( R2=0.95)显示可溶性固形物含量、果实硬度、果实横径是主导产量因子。综上，果实膨大后期喷施尿素硝酸铵钙溶液叶面肥可协同调控灰枣糖酸代谢与光合产物分配，显著提升果实品质及产量。

This study aimed to clarify the effect of foliar application of urea ammonium nitrate calcium at different growth stageon fruit morphology, quality, and yield of grey jujube fruits in Xinjiang so as to provide theoretical basis and practical guidance for scien.tific fertilization and quality improvement of jujube. Using water spray as the control, 5 treatments with foliar application of 2 g/kg ureaammonium nitrate calcium solution were set up at the flowering stage, young fruit stage, early fruit enlargement stage, and late fruit en.largement stage. Fruit longitudinal diameter, transverse diameter, firmness, soluble solid content, vitamin C content, titratable acid con.tent, and yield data were determined. Result showed that when the foliar fertilizer (2 g/kg urea ammonium nitrate calcium solution) wasapplied at the late fruit enlargement stage, fresh jujube fruit achieved the highest single fruit weight (11.15 g), yield (11 183.0 kg/ha), sol.uble solid content (378.5 g/kg), and vitamin C content (3 815.0 mg/kg), which increased by 5.49%, 50.52%, 23.46%, and 33.55%, re.spectively, compared with those in the water spray control. The titratable acid content reached the lowest value (0.9 g/kg), decreasing by53.57% comparedwiththecontrol. Fordriedjujubefruits,the highestfruitfirmness(17.46Pa)was observedwhenfoliarfertilizerwas ap.plied at the early fruit enlargement stage, which was 29.72% higher than the water spray control (P < 0.01). Correlation analysis showedthat soluble solid content, fruit firmness, and fruit longitudinal and transverse diameter were significantly correlated with dried jujubeyield (P < 0.05). The multiple regression model (R2= 0.95) indicated that soluble solid content, fruit firmness, and fruit transverse diame.ter were the dominant factor influencing yield. In summary, foliar application of urea ammonium nitrate calcium solution at the late fruitenlargementstage cansynergistically regulatesugar-acid metabolism andphotosynthate allocation in greyjujubes, therefore，significant. lyimprovingfruitqualityandyield.

S147.23；S665.1

企业横向项目(20230022)；塔里木大学校长基金项目(校 2024038)。