ARS | Publication request: Genetic diversity assessment of Saccharum species and elite cultivars from China using SSR markers

Submitted to: Guihaia
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: August 30, 2010
Publication Date: September 30, 2010
Citation: Liang, J., Pan, Y.-B., Li, Y.-R., Fang, F.-X., Wu, K.-C., You, J.-H. 2010. Genetic diversity assessment of Saccharum species and elite cultivars from China using SSR markers. Guihaia. 30(5):594-600.

Interpretive Summary: Almost all sugarcane cultivars grown in the world today can be traced back to only a few common ancestral “POJ” (Java) and “CO” (India) series- varieties. Because of limited genetic base, the rate of genetic gains through sugarcane breeding has been slow and sugarcane breeders become more and more interested in studying the extent of genetic diversity of parental resources and tapping into the wild relatives to explore additional good traits. In this study, the genetic diversity among 52 commonly used parental clones of different geographical origins was evaluated using simple sequence repeat (SSR) DNA markers and capillary electrophoresis technique. All together, 327 DNA fingerprints were amplified from 21 pairs of SSR primers, of which 141 DNA fingerprints showed variability among the 52 parental clones. These DNA fingerprints were used for the construction of a fingerprinting database and the assessment of the extent of genetic diversity using DNAMAN software. There were only four distinguishable groups with genetic similarity values from 55 to 87%, indicating a need to explore a wider range of sugarcane germplasm including wild Saccharum species in modern sugarcane breeding to obtain good varieties with resistance/tolerance to biotic and abiotic stresses.

Technical Abstract: Genetic diversity amongst 52 sugarcane clones including Saccharum species and cultivars (used for breeding and commercial production since the beginning of 20th century) has been assessed using 21 Simple Sequence Repeat (SSR) markers and capillary electrophoresis (CE) technique. Use of 21 SSR primers resulted in amplification of 327 distinguishable SSR DNA markers with an average of 15.6 bands per primer. A total of 141 distinctive SSR alleles were scored, which have been used for construction of fingerprinting database and assessment of the genetic diversity using DNAMAN analyzing software and UPGMA algorithm methods. The highest genetic homology was 87%, observed between ROC 16 and TY 1, the lowest genetic homology was 55%. The UPGMA algorithm with SSR markers showed four distinguishable clusters of genetically similar species and varietal clones. The results indicated that using SSR markers in combination with CE is an efficient tool for fingerprinting database construction and assessment of genetic diversity. Occurrence of most cultivated clones in just 4 clusters indicated the exploitation of similar genetic database for the breeding purposes. The breeding programs should be tailored to exploit the wide range of germplasm using Saccharum species to get good varieties especially for disease or insect-pest resistance.