Assessment of genetic diversity among sugarcane cultivars using novel microsatellite markers

Genetic diversity based on the characterization of genetic makeup, using molecular markers is of utmost importance for breeders in crop improvement programme. A total of 26 microsatellite primers were used to determine the genetic diversity among 40 sugarcane genotypes including their parents. The polymerase chain reaction (PCR) products were examined for both size and polymorphism using these primers. Overall alleles are amplified with an average of 2.3 per locus in this study. Of the total 26 simple sequence repeat (SSR) markers, only 10 (38.4%) displayed polymorphism, with polymorphism index contents (PIC) values ranging from 0.15 to 0.67. The observed homozygosity (Ho) and gene diversity (Nei’s) for individual loci varied from 0.0000 to 0.277 and 0.129 to 0.473, respectively. Shannon’s informative index (I) was found to be highest (0.661) in SKM04 while the lowest was 0.252 in SKM01 SSR loci with an average of 0.524. Fixation index was also calculated which was in the range of -0.074 to 1.00. A genetic relationship among cultivars and parental genotype was also analyzed by cluster analysis using unweighted pair group method with arithmetic mean (UPGMA), the average-linkage method, with the similarity matrix as input data. The genetic relationship and genetic diversity among the cultivars depicted from this study can be used to select the parents in sugarcane breeding programme. Keywords: Sugarcane, microsatellite, genetic diversity, SSRAfrican Journal of Biotechnology, Vol 13(12), 1444-145