Research Accomplishment Reports 2011

Breeding Sweet Sorghum for Syrup Production

T.W. Pfeiffer
Department of Plant and Soil Sciences

 

Non-Technical Summary

`Food and Wine' magazine included sorghum syrup among four extraordinary mail-order foods which were worth the treasure hunt. Sweet sorghum syrup production is an alternative income source for small farmers. Over 50% of the syrup producers raise five acres or less of sweet sorghum.

Sorghum producers are looking for new varieties which eliminate some of the deficiencies of currently available varieties while maintaining syrup quality. Attributes which could be improved include early maturity, resistance to red stalk rot and maize dwarf mosaic virus, higher sugar concentration in the stalk juice, and standability. Different sweet sorghum genetic types will be crossed to each other, and the progeny of the crosses will be analyzed for a combination of qualities not available in current varieties. Brix, a measure of sugar concentration, will be used to select sweet sorghum genetic types with new levels of sugar concentration. I anticipate identifying sweet sorghum types with higher levels of sugar and releasing a sweet sorghum variety which will reduce production constraints for sorghum syrup producers.

2011 Project Description

The sweet sorghum breeding project continued.

24 F4:6 lines were tested for a third year at Lexington KY. 116 F4:5 lines were grown for the first year at Lexington, KY. Data were collected on heading date, lodging, stem and leaf disease, biomass production, stem juice fraction and juice brix.

Additional sweet x grain sorghum backcrosses and sweet x sweet sorghum crosses were made.

Initiated the conversion of sweet sorghum varieties which are male sterility maintainer lines to male sterile A lines in a short stature which will enable combine harvesting of hybrid sweet sorghum seed.

Continued developing populations using two plant introductions, 152771 and 208190, which had been previously selected from a screen of 100 sweet sorghum introductions based on high brix of stem juice.

Events: Information on the project was presented at the Sweet Sorghum Producers and Processors Association annual meeting in February.

Products: Kentucky Foundation Seed Project continued to supply seed of the F1 hybrid KN Morris to sorghum syrup producers in the United States.

2011 Impact

Screening 12 sweet sorghum varieties for male sterility maintainer/restorer status showed 1/4 possessed the restorer allele while 3/4 were maintainers. M81E and N100 are male sterility maintainer lines.