Development of cpSSR markers for analysis of genetic diversity in Gladiolus cultivars

We report the development of 12 novel microsatellite (SSR) markers isolated from repeat sequences of chloroplast region of Gladiolus. A total of 1188 nucleotide sequences of chloroplast regions of Gladiolus were used to search for simple sequence repeats and 108 sequences were found to contain 124 SSRs. Dinucleotide repeat SSRs were most frequent (94.4%) with the AT/AT (59.7%) repeat motif followed by TA/TA (31.5%). Assessment of genetic diversity among 62 commercially important Gladiolus cultivars was carried out using 12 SSR markers. Out of 12 SSR markers, only six showed polymorphism with allelic variation ranging from 2 to 8. These six SSR markers revealed high genetic diversity (84.6%) across different Gladiolus cultivars. The average value of Polymorphic information content (PIC = 0.32) diversity index (2.03), expected heterozygosity (0.354) and Shannon's information index (0.522) were also significantly high. These markers could be utilized for future breeding programmes, genetic diversity studies, and germplasm management of this important ornamental crop.