Variation of the chemical composition of floral volatiles in the endangered Tunisian Pancratium maritimum L. populations (Amaryllidaceae)

► Eighteen volatile compounds were isolated from the flower of Pancratium maritimum firstly. ► High chemical variation was observed in the Tunisian P. maritimum populations. ► Four chemotypes could be reported in the Tunisian P. maritimum populations. ► P. maritimum populations showing high amounts of minor compounds should be preserved. Floral volatiles from thirteen populations of Tunisian Pancratium maritimum L. (sea daffodil), growing wild in mainland and island habitats were assessed by GC and GC/MS. Eighteen compounds representing 77.73% of the total oil were identified. The major components at the species level were heptacosane (12.07%), hexadecanoic acid (11.91%), benzyl benzoate (8.17%), octacosane (8.13%), and hexacosane (7.28%). Volatile composition varied highly among populations. Four chemotypes could be reported in the Tunisian P. maritimum populations. PCA analysis according to axes (1–2) and (1–3) revealed four and five groups of populations, respectively. The model of population grouping could result from local adaptation to micro-ecological factors contributing to the selection of particular compounds dictated by the isolation. Mainland and island populations showing high amounts of minor compounds should be collected, multiplied and preserved.