Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 12/9/2013
Publication Date: 6/10/2014
Citation: Knoll, J.E., Anderson, W.F. 2014. Development of hybrid sweet sorghum for the Southeast USA. Sweet Sorghum Ethanol Association annual meeting, Jan. 24, 2014, Orlando, FL. http://www.sseassociation.org/Presentations/SlideShow.aspx?presentationID=1091&page=1.
Interpretive Summary: not required
Technical Abstract: Sweet sorghum (Sorghum bicolor) has potential as a multi-purpose biofuel crop in the Southeast USA. The sugars from the juice can be easily fermented into ethanol or used to produce other chemicals, while the bagasse could be burned in boilers for energy or used for cellulosic ethanol. The grain and leaf portions could be utilized as livestock feed. The crop is more tolerant of heat and drought than corn (Zea mays), and requires less N fertilizer. Despite its advantages, most current cultivars are pure lines that produce little seed on very tall plants, which is a major limitation to development of a sweet sorghum-based biofuel industry. There is a need to develop hybrid seed production on short-statured seed parents. Hybrids should also be more productive than pure lines. We are evaluating the potential of hybrid sweet sorghum in the USDA-ARS breeding program at Tifton, GA. Using some of the currently available germplasm, a Design II mating design was constructed using three male-sterile (A-line) seed parents and 19 pollen parents to generate 57 hybrids. In 2012 all the hybrids, male parents, and the male-fertile (B-line) versions of the females were planted in a randomized complete block design with two replications. Each plot consisted of two rows. One row was used for sampling, while the other was harvested for total biomass at the end of the test. Over the course of the growing season, juice BRIX was sampled at regular intervals to monitor sugar production. At harvest, a sample of three stalks was taken from each plot, and these were separated into leaves, stalk, and panicle. The juice was extracted from the stalks with a roller mill and was quantified. Other traits measured included plant height, lodging score, and days to 50% anthesis. Hybrids tended to flower earlier than their male parent, but generally had similar height and plot biomass as the male parent. Female parent N109A appears to show good general combining ability for lodging resistance. A subset of these hybrids were tested in 2013 under three planting dates to assess the effects of environment on hybrid performance.