Analysis of genetic diversity in Guinea yams (Dioscorea spp.) using AFLP fingerprinting

Genetic diversity and resulting heterotic groupings in Guinea yams (Dioscor ea rotundata and D. cayenensis) and their wild relative D. praehensilis wer e assessed using Amplified Fragment Length Polymorphism (AFLP) genetic mark ers. Amplified Fragment Length Polymorphism generated DNA fingerprinting pa tterns of 19 varietal groups of cultivated yams and 1 wild species, D. prae hensilis. Two primer combinations generated a total of 87 polymorphic loci across the 20 varietal groups analysed. Five major groups were recognized i n the germplasm based on the neighbour-joining method of cluster analysis a nd the Statistical Analysis System multiple correspondence analysis procedu re. Among these, four varietal groups which corresponded to D. praehensilis (cv. Grovota). D. cayenensis (cvs Yaobadou and Kpokpokpokpo), and D. mange notiana (cv. Kappe-bolanda) were genetically distant from a core of 16 vari etal groups of D. rotundata. Among these, two varietal groups (cvs Dobnawo and Koukou) from Cameroon clustered separately from the West African genoty pes. The results of the present study showed that AFLP analysis is a sensit ive and robust DNA fingerprinting technique for genomic analysis in yams.