Genetic diversity and phylogenetic analysis of Robinia pseudoacacia L. populations using ISSR Markers, ITS1 and trnL-F Intergenic spacer sequences

Abstract

Background Robinia pseudoacacia L. is a deciduous tree planted almost all around the world for a wide variety of uses such as ornamental in urban ecosystems and forest trees in afforestation. This study aimed to evaluate the genetic diversity of of R. pseudoacacia plants planted in urban ecosystems using R. pseudoacacia genotypes collected from Istanbul (Prince Island, Bağdat Avenue, Barbaros Boulevard and TEM highway) and Kocaeli (Dilovası District) cities. Methods and Results 15 ISSR primers were tested, nine of which gave clear and distinguishable bands with a total of 100 loci. The percentage of polymorphic loci (PPL) was calculated as 100% for multi-populations and ranged from 46% to 76% for single populations. Genetic diversity values based on Nei’s (1978) were calculated between 0.165 and 0.251. The lowest and highest PPL were found in Barbaros Boulevard and Dilovası District populations, respectively. Population structure analysis showed seven different structures for the five populations. The most genetically similar populations were found as Prince Island and Barbaros Boulevard populations, while the most diverged population was the Dilovası population. Phylogeny analysis was conducted based on ITS1 and trnL-F IGS sequences. The length of the ITS1 sequence was found as 239 bp, and the GC content ranged from 52.72% to 56.56% while the length of the trnL-F IGS sequence was found as 453 bp with GC content between 29.14-29.80%. Conclusion It is considered that the main reasons for the genetic similarities and differences is originating from either the parents of these trees or the pollution they are exposed to. In phylogenetic analysis, both region sequences showed a high discriminant value and effective discriminatory power at the family level.