Molecular marker-based genetic diversity analysis in castor genotypes (Ricinus communis L.)

Castor is an important oilseed in the industrial sector for its application in various fields. The study was conducted with the twenty selected genotypes. 15 RAPD primers were amplified a total of 112 bands. Among these 106 bands were polymorphic, and 6 were monomorphic. The average per cent polymorphism obtained for RAPD primers was 96.67 %. Average PIC values for RAPD markers were 0.81 per primer and RPI with an average value of 6.16. 12 ISSR primers amplified a total of 54 bands out of which 49 were polymorphic and 5 bands were monomorphic. The average PIC value for ISSR was 0.67. The average IPI was 3.14. The similarity coefficient of cluster analysis was in the range of 15.0 % – 76.31 % for RAPD, 40.74 % – 92.59 % for ISSR and 28.8 % – 80.7 % for the pooled study. Dendrogram construction with UPGMA analysis shows that JI-456 for RAPD, SKP-84 for ISSR and JI-456 for pooled analysis as the most diverse genotypes among the twenty genotypes. These results will be helpful in the selection of the genotypes for future breeding programs to increase the specific traits. The important challenge faced during the research work were the isolation of genomic DNA from the leaf sample, as it was highly prone to pigmentation issue and this was overcome by slightly changing the composition of extraction buffer. The another difficulty faced during the work were setting up of the PCR protocol for marker amplification the minimum reaction volume for PCR leads to amplification issues and this overcome by increasing reaction volume.