Assessing genetic diversity and population structure in Tulipa species from Türkiye and Kazakhstan

Over the past two decades, genetic diversity within the Tulipa genus has been extensively studied using various morphological and molecular methods. However, the natural diversity of the Tulipa genus in Türkiye remains largely unexplored. The purpose of this study was to reveal the diversity of novel Tulipa species sampled from Türkiye and Kazakhstan, both of which have unique cultural histories and genetic diversity. In this study, iPBS (inter-primer binding site) markers were used for the first time in tulips grown naturally in Türkiye and Kazakhstan. The ability of iPBS markers to assess the genetic relationship between the preferred tulip varieties was revealed. According to the results of our study, it became clear that methods for determining iPBS markers can be easily used in studies of the genetic diversity of Tulipa species. To achieve the aforementioned aim, this study applied the iPBS method, which provides the theoretical novelty of this research. In addition, a total of 47 genotypes belonging to 14 Tulipa species that were selected based on their natural distribution in Türkiye and Kazakhstan were characterized morphologically and molecularly using 12 iPBS primers. The findings revealed significant variability in morphological traits among the Tulipa species. Notably, high variations were observed in flower size, leaf and stem characteristics, and bulb growth traits. Similarly, iPBS revealed high diversity with similarity indices ranging from 0.35 to 0.87 among genotypes. Principal component analysis (PCA) plots, both two- and three-dimensional, grouped the species into four distinct clusters, according to their origin. Structure analysis further confirmed the population structure, identifying four subpopulations. This study highlights the importance of species/genotypes with notable morphological and genetic traits within a highly variable population, providing insights into tulip breeding programs and utilization of natural genetic resources in sustainable agricultural production.