Genetic Diversity and Relationship of Hybrid Cymbidium Based on AFLP Marker

The genetic diversity and relationship of 42 cultivars of hybrid Cymbidium introduced from Japan,Korea and USA,and 2 wild species from China(C.aloifolium and C.floribundum)were evaluated using AFLP molecular markers in this study.Among the 1 597 AFLP bands obtained from nine selective primer pairs,1 565(98.0%)were polymorphic.The average number of DNA bands per primer pair was 177,with a range of 156-193.All the cultivars have their characteristic bands and can be identified based on the AFLP markers.Genetic similarity based on dice coefficients among the cultivars ranged from 0.3399 to 0.8223,with an average of 0.5783.The cultivars could be divided into four groups based on the UPGMA dendrogram,and this division is in consistence with the morphological classification based on the type of flower inflorescence,flower size or flower color.Cultivars originated from the same country or the same breeding company could be clustered together in the AFLP dendrogram and this represents the genetic relationship of the cultivars.