Polymorphic information and genetic diversity in Brassica species revealed by RAPD markers

Abstract

Randomly amplified polymorphic DNA (RAPD) is a tremendously convenient approach used to discriminate between Brassica species owing to its accuracy and speed. RAPD primers generate adequate genetic information that can be used in the primer-marker system. In this work, twenty RAPD-PCR based markers were executed to generate polymorphic data, like polymorphic information content (PIC), mean resolving power (MRP), resolving power (RP), effective multiplex ratio (EMR), and marker index (MI) for the first time and genetic distance among and between six Brassica species were calculated. Our results indicated that 20 primers produced a total of 231 scored band and generated 87\% polymorphic bands. Average PIC, MRP, RP, MI, and EMR values were 0.088, 0.65, 6.7, 0.78, and 8.9, respectively. PIC showed an overall negative correlation with MRP, RP, MI, and EMR, whereas MRP, RP, and EMR, were positively correlated with each other. Genetic identities ranged from 41.99\% (between Brassica napus and Brassica oleracea) to 68.83\% (between Brassica campestris and Brassica oleracea). Dendrogram results showed no clustering between species except between Brassica campestris and Brassica nigra. Nevertheless, these results will be helpful to acquire useful information about the markers and their use to determine the genomic structures of Brassica species. Further, based on genetic distance and polymorphic information, new hybrids can be developed for effective oilseed production.