Rapid detection of polymorphism in yams (Dioscorea sp) through amplification by polymerase chain reaction and rDNA variation

Ribosomal DNA (rDNA) from rice (Oriza Sativa) was used to examine polymorphism in 12 yam (Dioscorea sp) cultivars. Restriction enzyme digests of total yam DNA was probed with the pRR217 probe containing the entire repeat unit of rDNA from rice. The polymerase chain reaction was also used to amplify genomic DNA of six of the 12 cultivars studied using random primers. The amplification patterns of D rotundata‐cayenensis cv tau suggested that ‘tau’ is more closely related to D rotundata sp than it is to the D cayenensis sp. The results showed polymorphisms among the different yam cultivars.