Evaluation of long primers for AP-PCR analysis of mungbean [Vigna radiata (L.) Wilczek]: Genetic relationships and fingerprinting of some genotypes

There are a number of applications of molecular markers in agriculture such as assessing genetic diversity, generating DNA fingerprints and developing markers linked to a trait of interest, etc. Arbitrarily Primed-Polymerase Chain Reaction (AP-PCR) in which template DNA is amplified using single arbitrary primers of 10 base in length is a widely used technique. The objectives of this investigation were: (a) to compare efficiency of long primers (ranging from 18 to 22 base in length) and 10 base primers in detecting RAPDs in mungbean and (b) to evaluate some selected long primers for their ability to discriminate 46 mungbean genotypes and to study the genetic relationships among them. Both the groups of primers were evaluated for the total number of discrete and detectable amplified fragments and polymorphic bands detected between two mungbean genotypes. The long primers yielded significantly higher number of discrete and detectable bands as well as polymorphic bands than 10 base primers. A set of eight long primers was used for AP-PCR analysis of 46 mungbean genotypes. A total of 173 fragments were amplified of which 39.08 % were polymorphic. AP-PCR profiles from only three primers were sufficient to differentiate all the genotypes. A high degree of genetic variation was observed among different genotypes, whereas, those originating from the same source were highly related. The results show that long primers can be used for efficiently analysing genetic diversity and the relationships in a large mungbean germplasm collection.