Assessment of Infraspecific Genetic Diversity in Nepeta kotschyi Boiss., a Native Iranian Medicinal Plant

The genus Nepeta is one of the largest genera in the Lamiaceae family, and Iran is one of the main centers of origin of this genus. The genetic diversity estimation of the genus Nepeta germplasm provides a basis for future biodiversity conservation efforts and also for the selection of high-productive genotype(s) for the field production improvement. In this work, eleven RAPD primers with suitable banding pattern and prominent polymorphism were used for the estimation of infraspecific genetic diversity of N. kotschyi based on 21 populations. The study included 19 and 2 populations belonging to var. persica and var. kotschyi, respectively. Eleven primers amplified totally 225 scorable RAPD loci, 204 of which were polymorphic. The average number of bands per primer was 20.5, 18.5 of which were polymorphic. Primers OPF 05, OPB 15, OPT 14, OPO 07, and OPF 14 were the most powerful for the detection of the genetic diversity across the samples. Cluster analysis showed six genotypic groups. N. kotschyi var. kotschyi populations were placed in a group separated from the samples belonging to N. kotschyi var. persica. The same analysis showed that the genetic diversity pattern corresponds to the geographical distribution of the populations. Of the total variation in the studied germplasm, 32% was related to inter-populations and 68% to intra-populations variation. The results indicated the high potential of RAPD markers to resolve the status of the studied genotypes in regard to inter- and intra-populations diversity and to diversify N. kotschyi varieties previously resolved by morphometric methods.