Molecular Marker Systems for Fingerprinting and Diversity Analysis of Rice Germplasm Resources

The genetic variability and relationships among 265 rice germplasm accessions from the Genebank of Philippine Rice Research Institute were established from DNA fingerprints generated by two resistance gene analogue(RGA) markers: C-terminal leucine-rich repeat(CLRR) and ribonuclease inhibitor leucine-rich repeat(RLRR),and two universal primer markers: Seoulin Research Institute Life Science-6(SRILS6) and Seoulin Research Institute Life Science-8(SRILS8).The DNA fingerprints showed that CLRR was the most discriminating marker,generating 48 polymorphic bands in the germplasm samples with an average of 28.6 bands per accession,thus it was the most efficient marker for rapid DNA fingerprinting analysis.On the average,the RGA and SRILS primer markers showed the similar power in detecting the polymorphism within the population at the entire germplasm population level,and the average percentage of polymorphic bands generated by RGA and SRILS primer markers was 60.6% and 60.5%,respectively.Seven dendrograms were generated based on the banding profiles generated by RGA and SRILS primers or their combinations,featuring two major groups: group Ⅰ and group Ⅱ.Dendrogram analysis showed that both RGA and SRILS primers could distinguish all 265 accessions,and revealed a high level of diversity among the accessions.The clustering patterns and the compositions of the groups had the similarity of 88%~97% among the seven dendrograms.This indicated that the genomic regions amplified by these particular RGA and SRILS markers might have undergone mutations at comparative rate so as to manifest highly consistent genetic trees.