Variability of exudate flavonoids and genetic diversity of Satureja kitaibelii natural populations

Satureja kitaibelii Wierzb. ex Heuff. (Lamiaceae) is an endemic species distributed along the Balkan mountain range, used to prepare herbal tea. Due to its medicinal properties, this plant is over-exploited in its natural habitat, and in Serbia, it is considered endangered. This work assesses genetic diversity using phytochemical and molecular markers to explore breeding potential and develop tools and biomarkers for authentication. Surface flavonoids and inter-simple sequence repeat (ISSR) markers were used to analyze the natural populations of S. kitaibelii. Five flavones and one flavanone were detected in ninety samples, all highly substituted with multiple hydroxy and methoxy groups. In most populations, 5,4′-dihydroxy-6,7-dimethoxyflavanone and 5,4′-dihydroxy-6,7,8-trimethoxyflavone (xanthomicrol) were highly abundant flavonoids, although the flavonoid profile varied between populations. Genetic analysis using ISSR markers showed that most variability lies within the populations (75.9 %), whereas the rest was between populations. Both markers showed the existence of two gene pools in all statistical analyses, with a difference in the position of population Poganovo, which was grouped with different clades on these two markers. The observed genetic variability and consistency of traits give a basis for breeding strategies, and both markers can be used to assess genetic diversity in natural populations.