Genetic Diversity and Essential Oil Composition of some Mentha species.

This study investigated the physiological, biochemical, and genetic characteristics of various mint
species, focusing on chlorophyll content, essential oil composition, and genetic relationships. Assessment
of total chlorophyll content using SPAD revealed significant variability among species as Mentha
suaveolens exhibiting the highest levels (36.6) however M. piperita had the lowest value (28.0). Essential
oil analysis by GC-MS highlighted the presence of monoterpenes and sesquiterpenes in low
concentrations across the species. Notably, M. piperita uniquely contained germacrene D, while M.
suaveolens showed the highest amounts of β-caryophyllene. Dominant oxygenated monoterpenes were
identified, with M. spicata rich in carvone (70.979%) and M. longifolia in menthol (21.851%). Genetic
analysis using the ITS region yielded unique bands for all species, revealing varying degrees of genetic
similarity with M. spicata and M. longifolia demonstrating the closest genetic relationship. Overall, the
findings indicated a complex interplay between SAPD, essential oil composition diversity, and genetic
relationships in Mentha species.