CHEMICAL COMPOSITION OF VOLATILE COMPONENTS IN THE LEAVES OF CITRUS PLANTS CULTIVATED UNDER GREENHOUSE CONDITIONS

The article presents the results of research of the chemical composition of easily volatile components in the leaves of nine taxa representing species and varieties of the genus Citrus L. cultivated under the conditions of greenhouses of the Central Botanical Garden of the National Academy of Sciences of Belarus as: C. unshiu (Tanaka ex Swingle) Marcow., C. grandis Osbeck cv. Bogatyr, C. sinensis Osbeck cv. Washington Navel, C. medica L. cv. Sarcodactilis, C. medica cv. Pavlovskiy Shishkan, Lemon Skernevitsky (’Ponderosa lemon’) is a clone of the hybrid C. medica L. × C. limon (L.) Burm. f., Citrofortunella microcarpa, C. limon (L.) Osbeck cv. Pavlovskiy, C.meyeri (Ju. Tanaka). The volatile components were extracted using a Supelco™ solid-phase microextractor placed in the vapour-air space above air-dried, finely ground and heated to 40 °C leaf samples. The component composition of the extracts was analyzed by the GC/MS method using the Agilent Technologies 6850 Series II system (Network GC System/5975B (VL MSD). Total 36 components were identified in the leaves of citrus plants: monoterpenes (14), sesquiterpenes (11), and oxygen-containing compounds: terpene alcohols, aldehydes, ethers (11). The studies have shown that the cyclic hydrocarbons monoterpene (Z)-β-trans-Ocimene and 3 sesquiterpenes (β-caryophyllene, (3E, 6E)-α-farnesene, and α-caryophyllene) were detected in the volatile components in leaves in the whole citrus group. While 2 sesquiterpenes: (3E,6E)-α-farnesene and α-caryophyllene are dominant for the most taxa based on their proportions in the total volume of volatile compounds. Sesquiterpene beta-Elemene is present as a dominant component exclusively in species and varieties representing the so-called “sweet citrus” group as it follows from the results of the studies: C. unshiu, C. grandis cv. Bogatyr, C. sinensis× cv. Washington Navel, C. meyeri, which allows one to consider it as a significant feature in the taxonomy of the genus Citrus L.

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