Sorghum is an important food crop for millions of people in Africa and Asia. Whole genome re-sequencing of sorghum EMS mutants exhibiting an alkali spreading value (ASV) phenotype revealed candidate SNPs in Sobic.004G163700 and Sobic.010G093400. Comparative genomics identified Sobic.010G093400 as a starch synthase IIa and Sobic.004G163700 as a starch branching enzyme IIb. Segregation analyses showed that mutations in Sobic.010G093400 or Sobic.004G163700 co-segregated with the ASV phenotype. Mutants in SSIIa exhibited no change in amylose content but expressed lower final viscosity and lower starch gelatinization temperature (GT) than starches from non-mutant plants. The sbeIIb mutants exhibited significantly higher amylose levels and starch GT and lower viscosity compared to non-mutant starches and ssIIa mutants. Mutations in SBEIIb had a dosage dependent effect on amylose content. Double mutants of sbeIIb and ssIIa resembled their sbeIIb parent in amylose content, starch thermal properties and viscosity profiles. These variants will provide opportunities to produce sorghum varieties with modified starch end-use qualities important for the beer brewing and baking industries and specialty foods for humans with diabetes.
These data files contain whole-genome resequencing data for sorghum genotypes with unique starch properties.
Cite this work
Researchers should cite this work as follows:
- Griebel, S., Westerman, R. P., Adeyanju, A. O., Addo-Quaye, C., Craig, B. A., Weil, C. F., Cunningham, S. M., Patel, B., Campanella, O. H., Tuinstra, M. R. (2019). Mutations in sorghum SBEIIb and SSIIa affect alkali spreading value, starch composition, thermal properties and flour viscosity. Purdue University Research Repository. doi:10.4231/3GBF-RS75