ISSR ارزيابي گوناگوني ژنتيكي انواع ليمو(لايم و لمون ) در استان فارس با استفاده از ويژگي هاي مورفولوژيكي و نشانگرهاي مولكولي

EVALUATION OF GENETIC VARIABILITY OF LIMES AND LEMONS IN THE FARS PROVINCE BY MORPHOLOGICAL TRAITS AND INTER-SIMPLE SEQUENCE REPEAT (ISSR) MARKERS

Inter-simple sequence repeat (ISSR) markers were used to study phylogenetic relationships among 18 genotypes of lime [(Citrus aurantifolia (Chrism.) Swing.] and lemon [(Citrus limon (L.) Burm F.] in south of Fars province. After extraction of total DNA from young leaves, PCR amplification was performed using 6 ISSR primers. Amplification products were separated by electrophoresis in 6% denaturing polyacrylamide gels containing 7M urea. DNA bands were detected by silver staining. Based on 333 total ISSR fragments and 215 polymorphic fragments generated, a similarity dendrogram was constructed using UPGMA cluster analysis. The 18 genotypes classified into three major groups. The first group consisted of only D3 which was separated from other two groups with low similarity value of 0.56. Morphological and molecular differences between D3 and other genotypes indicated that it was neither a lime nor a lemon. Members of the second group. D5 and G30 were identified as lemons because they were grouped with G24 (Lisbon lemon). The 3rd and largest group comprises various types of lime including Mexican lime and Tahiti lime. It was divided into two main subgroups. D1, D2 and D9 formed the subgroupl. In the subgroup 2, genotype D7 (Cucumber lime) with 0.79 similarity separated from other ten. Next, D13 (Tahiti lime) with 0.82 similarity value was distinct from others which are regarded as Citrus aurantifolia. Among the latter which includes acid limes of Darab and Jahrom, similarity value ranged between 0.85 to 0.96. Some of these genotypes, e.g. G31 and G14, have valuable genetic characteristics for breeding programs.