The present study was undertaken to evaluate genetic divergence among nine Egyptian cotton cultivars (Gossypium barbadense) random amplified polymorphic DNA analysis( RADP-PCR) and to assess the relationship between Euclidean distance and Nei s genetic distance. Screening of ten random primers with nine genotypes of cotton indicated that eight primers produce different polymorphic bands and amplified fragment DNA and generated a total of 123 amplification products, among which 118 were found to be polymorphic, with 95.90% poly¬morphism. All prim¬ers produced polymorphic amplification products, how¬ever, the extent of per cent polymorphism varied with each primer (75.0 to 100%). Genetic relationships among a number of genotypes can be summarized using cluster analysis to place similar genotypes into phenotypic groups. Relationships among the nine Egyptian cotton cultivars based on showed the dissimilarity matrix of the Euclidean distance using six fiber quality traits between all pairs of cotton cultivars ranging from 0.324 between Giza69 and Giza81 to 6.014 between Giza76 and Giza80;the average of distances among cultivars was 3.169.Nei s genetic distance between all pair of cotton cultivars ranged from 0.278 between Dendera and Giza 83 to 0.704 between Giza77 and Giza80 ; the average of similarity among cultivars was 0.491.UPGMA cluster analysis placed all the Egyptian cotton cultivars within their respective known taxonomic groups, while breeding centre-wise grouping of cultivars was not discerni¬ble. It indicates that breed-ers have not been working in isolation, and that breeding material for the development of these cultivars has been shared between the breeding stations and cotton improve¬ment programmes. |
