Morphological and Molecular Characterization of Iranian Wild Blackberry Species Using Multivariate Statistical Analysis and ISSR Markers

This study was carried out to estimate the genetic diversity and relationships of 74 Iranian blackberry accessions assigned to 5 different species using inter-simple sequence repeats (ISSR) marker analysis and morphological trait characterization. Sixteen traits were analyzed, including phenological, vegetative and reproductive attributes (in 57 out of 74 accessions), and 10 ISSR primers were screened (in 74 accessions).  The yield and leaf width had the highest and lowest genetic diversity, (diversity index = 62.57 and 13.74), respectively. Flowering and ripening date were recorded as traits with the strongest correlations (r = 0.98). Ten ISSR primers were selected and produced a total of 161 amplified fragments (200 to 3500 bp), of which 113 were polymorphic. The highest, lowest and average PIC values were 0.53, 0.38 and 0.44, respectively. Principle component analysis (PCA) was based on morphological traits and showed that the first six components explained 84.9% of the variations among the traits. Meanwhile, the principal coordinate analysis (PCoA) was based on ISSR data and implied the first eight principal coordinates which explained 67.06% of the total variation. Cluster analysis was based on morphological traits and ISSR data ultimately classified all accessions into two and three major groups, respectively, so that the distribution pattern of genotypes was mainly based on species and the geographic origins.