Objective This study aimed to investigate the variation patterns of volatile components and their contents in different tissues of Pandanus amaryllifolius Roxb. under gradient zinc concentrations, and clarify the differential accumulation characteristics of key volatile metabolites in different tissues, so as to provide a scientific basis for the targeted quality improvement of Pandanus amaryllifolius Roxb. through nutrient regulation.

Methods A field experiment was conducted with four zinc concentration treatments: 0 mg·L⁻¹ (T₁, control), 100 mg·L⁻¹ (T₂, low zinc), 200 mg·L⁻¹ (T₃, medium zinc), and 300 mg·L⁻¹ (T₄, high zinc). Combined with gas chromatography-mass spectrometry (GC-MS), untargeted metabolomic analysis of volatile components in the roots, stems, and leaves of Pandanus amaryllifolius Roxb. was performed to quantitatively evaluate the effects of different zinc concentration gradients on the content of tissue-specific volatile organic compounds in Pandanus amaryllifolius Roxb.

Results The results showed that the effects of zinc treatment on the volatile components of Pandanus amaryllifolius Roxb. were tissue-specific. Specifically, the leaves were the most sensitive to zinc. Under high zinc treatment, the content of furan compounds in leaves was significantly 2.68% higher than that under medium zinc treatment. In contrast, the contents of phenolic and ester compounds were inhibited under low, medium, and high zinc treatments compared with the control: the phenolic contents decreased by 6.31%, 1.91%, and 2.35%, respectively, and the ester contents decreased by 1.61%, 0.94%, and 0.87%, respectively. In stems, the phenolic contents increased by 2.49% and 2.36% under low and medium zinc treatments, respectively, while the contents of alcohols and esters decreased by 1.68% and 1.29% under low and high zinc treatments, respectively. The overall response of the root system was weak, with significant changes only observed in the volatile compound contents of lateral roots. Among them, the contents of ketones and esters decreased by 5.29% and 3.38% under low zinc treatment, respectively, whereas the contents of acids increased by 7.94% and 6.47% under low and medium zinc treatments, respectively. Compared with the control, the content of 2-acetyl-1-pyrroline (2AP),the key component of the characteristic aroma in Pandanus amaryllifolius Roxb., increased significantly by 0.23%, 0.08%, and 0.05% under low, medium, and high zinc treatments, respectively.Correlation analysis among volatile components indicated potential synergistic or antagonistic interactions that jointly regulate aroma quality.

Conclusion This study confirmed that the effect of zinc on the volatile components of Pandanus amaryllifolius Roxb. exhibited significant tissue specificity, and the leaves of Pandanus amaryllifolius Roxb. were the most sensitive to zinc compared with other tissues. Treatment with a low zinc concentration (100 mg·L⁻¹) may significantly improve leaf aroma quality by optimizing the ratio of furan/phenolic compounds and the characteristic aroma component 2AP. The results of this study will provide a theoretical basis for the development of precise fertilization schemes and high-quality cultivation techniques for Pandanus amaryllifolius Roxb., and contribute to the high-quality and sustainable development of the Pandanus amaryllifolius Roxb. industry.