Comparative Analysis of Genetic Structure and Diversity of Sorghum (Sorghum bicolor L.) Local Farmer’s Varieties from Sudan

Aims: Investigate the genetic diversity and structure of 50 Sorghum accessions from 10 different regions in Sudan and one from the county of Central Equatoria in the Republic of South Sudan, by screening 40 RAPD and 10 ISSR (Inter-simple sequence repeat) markers.

Study Design: UPGMA method using STATISTCA- SPSS software Ver. 9 and PCA using GenAlEx ver. 6.5

Place and Duration of Study: Department of Molecular Biology, Commission for Biotechnology and Genetic Engineering, National Center for Research, Khartoum, Sudan (2010-2012).

Methodology: 47 sorghum accessions with important agronomic traits, representing 10 states in Sudan and three sorghum accessions from the county of Central Equatoria of Republic of South Sudan were assayed for polymorphism using Random Amplified Polymorphic DNA (RAPD) and Inter-simple sequence repeats (ISSRs).

Results: Ten polymorphic RAPD primers distinguished 163 bands. 156 bands were polymorphic among the 50 accessions with 96.6% polymorphism. The seven polymorphic ISSR primers distinguished 78 bands, of which 75 bands were polymorphic with 97% polymorphism. The RAPD distance matrix ranged between 0.07-0.43 which proved wide range of variation, ISSR distance matrix ranged between 0.04-0.47 showing higher genetic variability among the sorghum accessions than the RAPD, whereas, combined data distance matrix for both RAPD and ISSR markers ranged between 0.08-0.39 which reflected more trusted result among Sudanese sorghum accessions. The White Nile state accessions showed the highest percentage of polymorphic loci with 39.75%, whereas lowest was given by Red Sea accessions with 17.99%. The molecular variance within states was 70% and 30% among states.

Conclusion: In conclusion, Results based on combined analysis of both RAPD and ISSR data were most accurate for covering large area inside the genome. White Nile state accessions was the highest in number of bands; number of private bands; percentage of polymorphic loci and heterozygosity (He) mean compared to accessions of other states.