Genetic diversity assessment of flax (Linum usitatissimum L.) germplasm using molecular and morphological markers

Abstract

The present investigation was undertaken to assess the genetic diversity of 48 flax germplasm using molecular and morphological markers. 90 SSR and 10 ISSR flax markers were employed for molecular diversity analysis. Out of these, 25 microsatellite markers were found to be polymorphic giving a total of 99 bands with an average of 3.96 bands per marker ranging from 2 to 12. The polymorphic information content (PIC) value of each SSR primer pair ranged from 0.21 to 0.88 with an average of 0.49 while, in case of ISSR primers, out of 10 primers, only 2 were found polymorphic producing a total of 20 bands with an average of 10 bands per marker ranging from 2 to 11. The polymorphic information content (PIC) value of ISSR primer pair ranged from 0.62 to 0.75 with an average of 0.68. Cluster analysis based on Jaccard’s similarity coefficient using UPGMA grouped the 48 flax genotypes into two clusters and ranged from 0.56 to 0.97 with an average similarity index of 0.76. Whereas, in morphological divergence, 48 flax genotypes were grouped into five clusters using Tocher’s method in Mahalanobis D2 statistics. Cluster IV comprising most of the divergent genotypes. The genotypes in cluster III and cluster V exhibited high degree of genetic diversity. Cluster III reflected high cluster means for seed yield per plant, number of capsules per plant, number of primary branches per plant and number of secondary branches per plant. It was evident from both the diversity analysis that two introduced genotypes Neela and R-4158 were the most divergent genotypes followed by PKDL -43, RLC-137, KL-168 and R-4152.

Keywords

• clusters
• genetic diversity
• dna
• flax
• linum usitatissimum
• molecular markers