Analysis of genetic diversity and association of seed and mucilage yields with inter simple sequence repeats (ISSR) polymorphism in a collection of Plantgao species

Analysis of genetic diversity in medicinal plants assists germplasm conservation and selection for use in breeding schemes. The aims of the present study were to assess genetic diversity and differentiation of several Plantago species using Inter Simple Sequence Repeats (ISSR) markers and identify marker-trait associations (MTAs). Thirty-one Plantago accessions belonging to eight species with various mating system and chromosome number were collected from geographical regions of Iran environments. Polymorphism in the DNA of Plantago accessions were analyzed using polymerase chain reaction (PCR) of 25 ISSR primers. The data for number of polymorphic bands were analyzed on the basis of several genetic diversity parameters. The results of gel analysis indicated that the ISSR primers amplified 5 to 21 polymorphic bands with 100 to 3000 bp size. The mean polymorphism was 83.83% and five primers showed 100% polymorphism among Plantago accessions. The Polymorphism Information Content (PIC) for ISSR as a dominant marker ranged from 0.1103 to 0.3829 with the mean 0.2727 in the species tested. Accessions in P. amplexicaulis and P. pysillum species represented the highest Neis and Shannons genetic diversity whilst the lowest obtained for P. lagopus. Analysis of phylogenetic network generated by the Neighbor-Net Algorithm showed moderate split of the eight species tested and the network depicted moderate conflict. The principal coordinate analysis (PCoA) results showed lower conflict in separation of accessions of the eight species. Fifty-six significant MTAs were detected for the traits tested in Plantago accessions, of which six were shared between three seed and mucilage traits and 24 were common between two traits. The coefficient of determination (R2) for the identified MTAs varied between 32 and 73%. In conclusion, the results of genetic diversity analysis suggested that ISSR marker could efficiently differentiate Plantago species and the information of genetic diversity might assist Plantago improvement and conservation.