Evaluation of genetic diversity among Iranian apple cultivars using ISSR-markers

Apple (Malusdomestica Borkh) from Rosaceae family is one of the most important fruit trees in the world. Evaluation of genetic diversity is one of the basic steps for plant breeding and preserving of germ plasm through gene banks. The aim of this study was evaluation of the genetic diversity of 22 varieties of apples collected from Khorasan Aagricultural Research Center and some region of Jiroft using ISSR markers based on the polymerase chain reaction (PCR). DNA extraction was done and then PCR conducted by five ISSR-primers. Apple cultivars had 81.48% polymorphism. Cluster analysis classified them into six groups. The first group had five apple cultivars from Khorasan Razavi including Mohali Gonabad, Tabasi number3, Ghasemabai, Mohamadi and Golshahi Oghaz as well as Golab Esfehan, Sibe Ghermez and Gerani Esmith from Jiroft. Genotypes of Zard Lobnan, Sib Ghermez Khoni, Mohali Sardo, Golab Sardo from Jiroft and Mashali, Morabei Mashhad, Ali Mori Dovom Ras, Arbabi, SIB number3 from Khorasan Razavi categorized into the second group. Genotypes of Shaikh Ahmad Tabriz and Shafiabadi were placed in the third and forth group respectively. The fifth and sixth groups include Gol Mashhad and Abasi Azghade, Atlasi Tabas from Khorasan Razavi. Also, ISSR primer 842 showed the highest polymorphism among apple cultivars. There is no correlation between the geographical origin and genetic grouping of apple cultivars. Probably, setting of different regions genotypes in the same genetic group is due to transport of genotypes among regions in past. Results indicated that ISSR is an effective technique for identification of polymorphism, genetic distance and germplasm management among apple cultivars.