An evaluation on the degree of polymorphism in safflower accessions using RAPDs

Abstract

Ngugi Kibaki Kemboi

Safflower is a drought tolerant annual oil crop and this gives it an advantage over the other crops in the drier parts of Kenya. It is valued worldwide as a source of high quality vegetable oil. In the past, characterization of safflower using molecular markers has been limited. The objective of this study was to evaluate the degree of polymorphism in 36 safflower accessions using RAPDs. Sixty-one amplification products were scored using 14 random 10 mer primers and binary matrices subjected to statistical analyses using NTSYS. A resemblance matrix was developed using SMC, which was used with the UPGMA to compute cluster analysis and PCA. Eight groups were formed at a similarity coefficient of 0.79. Cluster two had 14 accessions originating from India, USA, Australia and Bangladesh while cluster three had 9 accessions from India, USA and Mexico. Proportionally accessions from India were highest in cluster one and two. The differences between pairs of accessions were basically related to the number of RAPD fragments shared. Four Indian accessions PI 214150, PI 199910, W6 16821 and PI 248359 clustered together. However, Girna also from India formed an independent cluster. SMC among accessions ranged from 0.37 (PI 248359 and PI 262419) to 0.98 (PI 560177 and T65) . The last two accessions may be genetically related since they constituted the nearest to a complete match for all markers. Accessions from different countries tended to group together though random scattering often occurred. Using PCA the first three components explained 44% of the total variation. The results indicate genetic polymorphism between the safflower accessions under study.