Evaluation of genetic variations in saffron with more than three stigmas using SSR and ISSR molecular markers

Saffron is the most valuable spice in the world. It is genetically a monomorphic clone. However, differences in phenotype and quality have been reported. The most important agro-economically phenotypic variation is the appearance of flowers with more than three stigmas. The main objective of this study was to study the genetic variability of saffron clones with more than 3 stigmas using SSR and ISSR molecular markers. In this research, saffron clones with more than three stigmas were collected along with the corm and the root from Saffron fields of Qaen and Sarayan, South Khorassan province, then transferred as a whole to the Biotechnology Laboratory of the Faculty of Agriculture, the University of Birjand. The number of stigmas in each flower was counted. Genomic DNA was extracted according to the CTAB method from leaves of the flower with more than three stigmas. Flower with more than three stigmas was larger and had more petals than ordinary ones. The most frequent number of flowers with more than three stigmas was related to four and five stigmas with 38%. Six-spike samples with a frequency of 14% were observed. Among the collected samples, only one specimen with seven stigmas was observed. Of the 48 tested ISSR primers on the bulk of DNA, only 16 primers had amplified bands and selected. The results of agarose gel electrophoresis for ISSR primers amplified the bands ranged from 100 to 1000 bp. By examining the bands formed for ISSR primers, no significant polymorphism was observed between different clones of saffron. Therefore, based on this marker system, no sign of genetic diversity was observed between clones with different number of stigmas. Among the tested SSR markers, 10 primer pairs showed amplified band among the clones. The results of correlation analysis based on Spearman correlation coefficient showed that there was no statistically significant correlation between microsatellite marker alleles and number of stigmas.