This study comprised a comprehensive GC-MS (gas chromatography-mass spectrometry) fingerprinting of leaf cuticular waxes in four Chaenomeles Lindl. species—C. japonica, C. speciosa, C. × superba, and C. cathayensis. The growth of said species has prevailed growth under diverse agroclimatic conditions of Moscow (temperate) and Crimea (Yalta) (subtropical), Russia. The identified metabolites totaled 54, including terpenoids (13), fatty acids (FA) (9), glycerides (7), alcohols (6), alkanes (5), organic acids (4), phytosterols (4), polyphenols (4), vitamin E, and sucrose. The waxes displayed characteristics of the highest content of long-chain compounds (C28–C33), with C30 triterpenes being the dominant fraction overall. Southern ecotypes exhibited a prolonged profile of terpenoids, alkanes, and sugar alcohols, revealing an adaptive enhancement of the leaf hydrophobic barrier against heat and UV stress conditions. Remarkably, the phytosterol stigmast-5-ene reached its identification for the first time in Chaenomeles leaf waxes, exhibiting a considerable accretion in Yalta samples compared with trace amounts in Moscow samples. The results enunciated that non-targeted GC-MS profiling provides a dependable basis for phytochemical recognition and appraising the ecological plasticity. Among these four species, C. cathayensis showed the most partial metabolite set, confirming a general trend toward reduced chemical diversity in the Moscow temperate region.
Chaenomeles, leaves, cuticular wax, GC-MS fingerprinting, agroclimatic adaptation, ecological plasticity
Assimilation of 54 metabolites into group-specific profiles revealed a dual nature of Chaenomeles cuticular waxes with species specificity and environmental plasticity, enabling vigorous identification of phytochemicals.