IDENTIFICATION OF IN-VIVO AND IN-VITRO LEMON MUTANTS BY RAPD MARKERS

Random Amplified Polymorphic DNA (RAPD) assay was performed for the identification of 14 in vivo and one in vitro lemon mutants in comparison with a known zygotic origin genotype. Thirty six 10-mer arbitrary primers were employed to detect RAPD markers. Fourteen of the tested primers generated sole monomorphic profiles and 22 produced 43 polymorphic fragments in a total of 294 loci. With the polymorphisms obtained in the present assay, all the 16 lemon genotypes were identified. Among the 43 RAPD markers, 28 were unique to a single genotype, of which 20 were specific to 'Interdonato', four to 'Ruvittaro', three to 'Monachello' and one to 'Femminello Continella'. The results of the pairwise analysis of the RAPD data indicated that 'Interdonato' was genetically distinct from the other lemons, while high similarities were observed among the remaining genotypes. High reproducibility of RAPD technique was observed in the analysis of three DNA preps. The RAPDs obtained in the present study have provided the first molecular markers enabling the discrimination of citrus cultivars differentiated by mutation.