Assessment of genetic diversity and relationships in pineapple cultivars from Thailand using ISSR marker.

Inter simple sequence repeats (ISSR) markers were applied to assess genetic diversity and genetic relationships among 15 accessions of pineapple (Ananas comosus (L.) Merr.) one of the most important agricultural economic fruits in Thailand. Genomic DNA was extracted from fresh leaf samples. Nine ISSR primers were initially screened for analysis and four primers (ISSR1, ISSR3, ISSR 4 and ISSR 5) were chosen for further analysis. A total of 56 DNA fragments, varying from 100-2000 bp, were amplified, of which 27 (48.21%) were polymorphic. A dendrogram showing genetic similarities among pineapple was constructed which based on polymorphic bands using the SPSS program (version 18). Based on the results from the dendrogram, three clusters could be separated with similarity coefficients ranging from 0.316-0.968. The first group included Intrachitdang and Intrachitkhao. The second group included Pattavia, Nanglae and Lakata. The third group included Tadum, Tainan, Pattanie, Phulae, Petburi, Sawee, Phuket, and Tradsithong respectively. Therefore, ISSR analysis is a rapid and suitable method for studying genetic diversity among indigenous Intrachit and others.