Genetic Diversity of Balm (Melissa Officinalis L.) Landraces and Genetic Relationship Within and Between Them using ITS Markers

The lemon balm (Melissa officinalis L.) a perennial medicinal plant, of Labiateae family is grown in the most parts of Iran and it has shown the sedative, hypnotic, analgesic, antiviral and antimicrobial effects. In present study, genetic diversity of 14 landraces of balm with two out group landraces (basil and moldavian balm) was investigated. Study variation within and between landraces of balm ITS (Internal Transcribed Spacer) region was used to design markers. Also four enzymes Taq1, EcoR v, BssM1 and AspLE1 were used for investigating polymorphism in ITS region. Enzyme BssM1 showed the polymorphism in number and length of digested fragments better than other enzymes. Mantel test results showed that the most correlation was existed between of dice dissimilarity matrix and Neighbor joining algorithm for data analysis. Among balm landraces highest degree of dissimilarity (0.44) was observed from Esfahan and Qazvin landraces and the lowest from 1, 6 and 10 landraces were quite identical. Diversity was observed just for five of landraces (3, 7, 8, 9 and 11). Results of cluster analysis separated landraces on eight groups and Basil genetic distances were less than moldavian balm to the balm and highest distance between groups 3 and 6 with 0.42 and the most similarity was between groups 1 and 4 (dissimilarity=0.15).