DOI: https://doi.org/10.21203/rs.3.rs-2494007/v1
Backgroud: Turkey is considered an important gene pool for the distribution of herbaceous Paeonia species. Twelve taxons were recorded in Turkey and all definitions are morphologically and/or anatomically performed. No studies have been conducted based on DNA barcode sequences. In this study, The matK and rbcL genes and ITS region were sequenced to determine phylogenetic relationships of 12 Turkish Paeonia taxa and chemical comparison was performed with root samples.
Methods and results: The taxons were collected between May and June 2021 from nine different cities. Leaf materials were used for DNA isolation and ITS, matK and rbcL regions were amplified and sequenced. There was no difference among taxa in terms of rbcL sequences. But the ITS and matK regions distinguished 12 taxa. The genotypes were structured in two groups by ITS and matK data. ITS region distinguished P. peregrina, P. arietina, and P. tenuifolia from other taxa, while matK region distinguished P. arietina and P. witmanniana from other taxa. Both barcode sequences actually showed that the registration of P. mascula subsp. arasicola was faulty and it is 100% similar to P. arietina. Twelve taxa were each found to have characteristic polymorphisms in both the ITS and matK regions that could be used to distinguish the species from each other. The most polymorphism was determined in the ITS region (n=54), while the matK region showed less variability (n=9). We also detected the barcode sequences could successfully discriminate the hybrid polyploid Paoenia species from diploid P. tenuifolia. Except for P. tenuifolia, the other Paeonia species were seen to be hybrid. The methanolic root extracts were examined for total phenolic content, total flavonoid content, and antioxidant activities (by FRAP, ABTS, and DPPH). The results revealed significant variation in extracts, polyphenolic content, and antioxidant properties. In 100 g root, TPC ranged from 204.23 to 2343.89 mg, TFC ranged from 7.73 to 66.16 mg, and FRAP ranged from 523.81 to 4338.62 mg. SC50 values of ABTS ranged from 115.08 to 1115.52 μg/ml and DPPH ranged from 73.83 to 963.59 μg/ml.
Conclusion: For the first time, genetic diversity and chemical comparison were performed among Paeonia species along Turkey. It was concluded that 11 of 12 taxa had differences in terms of ITS and matK sequences. It has been shown that barcode sequences must be used for the correct identification of Turkish Paeonia.