Assessment of genetic diversity and relationship among a collection of US sweet sorghum germplasm by SSR markers

• Published in: Molecular breeding Vol. 21; no. 4; pp. 497 - 509
• Main Authors: Ali, M. L, Rajewski, J. F, Baenziger, P. S, Gill, K. S, Eskridge, K. M, Dweikat, I
• Format: Journal Article
• Language: English
• Published: Dordrecht Dordrecht : Springer Netherlands 01.05.2008; Springer Netherlands; Springer Nature B.V
• Subjects: Alleles; Biomedical and Life Sciences; Biotechnology; Cluster analysis; Clustering; Cultivars; Gene polymorphism; Genetic analysis; Genetic diversity; Genetic relationship; Genetic variability; Germplasm; Grain; Life Sciences; Loci; Markers; Molecular biology; Pedigree; Plant biology; Plant Genetics and Genomics; Plant Pathology; Plant Physiology; Plant Sciences; Polymorphism; Similarity; Sorghum; Sorghum bicolor; Sugar; United States > US; Cluster analysis; Genetic distance; Genetic diversity; Genetic similarity co-efficient; SSRs; Sweet sorghum
• ISSN: 1380-3743; 1572-9788
• DOI: 10.1007/s11032-007-9149-z

Sweet sorghum (Sorghum bicolor L.) is a type of cultivated sorghums and has been recognized widely as potential alternative source of bio-fuel because of its high fermentable sugar content in the stalk. A substantial variation of sugar content and related traits is known to exist in US sweet sorghum. The objectives of the study were to assess the genetic diversity and relationship among the US sweet sorghum cultivars and lines using SSR markers and to examine the genetic variability within sweet sorghum accessions for sugar content. Sixty-eight sweet sorghum and four grain sorghum cultivars and lines were genotyped with 41 SSR markers that generated 132 alleles with an average of 3.22 alleles per locus. Polymorphism information content (PIC) value, a measure of gene diversity, was 0.40 with a range of 0.03-0.87. The genetic similarity co-efficient was estimated based on the segregation of the 132 SSR alleles. Clustering analysis based on the genetic similarity (GS) grouped the 72 sorghum accessions into 10 distinct clusters. Grouping based on clustering analysis was in good agreement with available pedigree and genetic background information. The study has revealed the genetic relationship of cultivars with unknown parentage to those with known parentage. A number of diverse pairs of sweet sorghum accessions were identified which were polymorphic at many SSR loci and significantly different for sugar content as well. Information generated from this study can be used to select parents for hybrid development to maximize the sugar content and total biomass, and development of segregating populations to map genes controlling sugar content in sweet sorghum.