Source: UNIVERSITY OF KENTUCKY submitted to
BREEDING SWEET SORGHUM FOR SYRUP PRODUCTION
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
TERMINATED
Funding Source
Reporting Frequency
Annual
Accession No.
0217108
Grant No.
(N/A)
Project No.
KY006065
Proposal No.
(N/A)
Multistate No.
(N/A)
Program Code
(N/A)
Project Start Date
Jan 1, 2008
Project End Date
Dec 31, 2012
Grant Year
(N/A)
Project Director
Pfeiffer, T. W.
Recipient Organization
UNIVERSITY OF KENTUCKY
500 S LIMESTONE 109 KINKEAD HALL
LEXINGTON,KY 40526-0001
Performing Department
PLANT & SOIL SCIENCES
Non Technical Summary
`Food and Wine' magazine included sorghum syrup among four extraordinary mail-order foods which was 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.
Animal Health Component
(N/A)
Research Effort Categories
Basic
30%
Applied
(N/A)
Developmental
70%
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
2022030108070%
2122030108030%
Goals / Objectives
OBJECTIVES: The long term objective is to improve sweet sorghum varieties for increased production and profitability. The five year objectives are to: 1) investigate sugar concentrations in plant introduction materials, and 2) select for early maturity and disease resistances in segregating populations. EXPECTED OUTPUTS: 1) Identify a sweet sorghum plant introduction with allele(s) for sugar concentration different than the alleles present in current sweet sorghum varieties. 2) Release a sweet sorghum variety for sorghum syrup producers which is earlier maturing than Dale but with disease and high stalk brix.
Project Methods
Objective 1) The seven plant introductions (out of 102 tested) with Brix greater than a current variety of similar maturity will be planted in multiple KY locations. Brix will be measured on juice pressed from stems of 12 plants per plot. Any entry with Brix equal to or greater than the maturity check variety will be crossed to other sweet sorghum varieties. Progeny generations will be analyzed on F2 single plants and F2:3 families to determine if transgressive segregates for Brix are obtained. Objective 2) Early x late maturity sweet sorghum populations will be created each year. In the F2 generation the 10% earliest heading plants will be selected The early heading individual plant selections will be screened as F2:3 families for red stalk rot resistance and as F3:4 families for MDMV resistance. Juice production and Brix will be measured on those early maturing lines which are selected as disease resistant. First year juice measurements will be made at Lexington. Second year juice measurements on the top 10% of lines selected from year 1 will be tested at two KY locations. Outputs will be evaluated by the increase in sugar concentration available in new germplasm. Value to syrup producers will be evaluated by seed sales of a new variety.

Progress 01/01/08 to 12/31/12

Outputs
OUTPUTS: Outputs: Kentucky Foundation Seed Project continued to supply seed of the F1 hybrid KN Morris to sorghum syrup producers in the United States. The project proposes releasing two pure line sweet sorghum varieties in 2013, lines KY08-0238 and KY08-1810-2 - variety names still to be determined. Dissemination: Information on the project was presented at the Mountain Field Day in September at the Robinson Center for Appalachian Resource Sustainability. PARTICIPANTS: Nothing significant to report during this reporting period. TARGET AUDIENCES: The primary target audience is members of the National Sweet Sorghum Producers and Processors Association and the Kentucky Sweet Sorghum Producers and Producers Association. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
Nine F4:8 lines were tested for a fourth year at Lexington and Quicksand KY. 21 F4:6 lines were grown for the second year at Lexington, KY. Data were collected on heading date, lodging, stem and leaf disease, biomass production, stem juice fraction and juice brix. Approximately 1000 F2:3 families were grown for evaluation and selection. Additional sweet x grain sorghum backcrosses and sweet x sweet sorghum crosses were made. The conversion of sweet sorghum varieties which are male sterility maintainer lines to male sterile A lines in a short stature continued; this will eventually enable combine harvesting of hybrid sweet sorghum seed. The development continued of 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. Change in knowledge: Nitrate accumulates in sorghum stems during drought conditions. The nitrate present in the sorghum syrup is higher than in the sorghum juice; with the nitrate being concentrated proportional to the water lost during syrup production.

Publications

  • No publications reported this period


Progress 01/01/11 to 12/31/11

Outputs
OUTPUTS: 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. PARTICIPANTS: Nothing significant to report during this reporting period. TARGET AUDIENCES: The primary target audience is members of the National Sweet Sorghum Producers and Processors Association. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
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.

Publications

  • No publications reported this period


Progress 01/01/10 to 12/31/10

Outputs
OUTPUTS: The sweet sorghum breeding project continued. 21 F4:6 lines were tested for a second year at Lexington and Quicksand, KY. Data were collected on heading date, lodging, stem and leaf disease, biomass production, stem juice fraction and juice brix. 116 F4:5 lines were grown for the first year at Lexington, KY. 14 F2 populations were grown at Lexington and individual plants were selected based on early heading date, no lodging, and biomass production as measured by plant height. 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, were compared in hybrid combinations with variety Dale. The primary trait of interest was juice brix. Additional sweet x grain sorghum backcrosses and sweet x sweet sorghum F1 crosses were made. Information on the project was presented at the Sweet Sorghum Producers and Processors Association annual meeting in February and at the Robinson Center for Appalachian Resource Sustainability field day in October. Kentucky Foundation Seed Project continued to supply seed of the F1 sterile hybrid KN Morris to sorghum syrup producers in the United States. PARTICIPANTS: The PI Dr. Todd Pfeiffer conducts the sweet sorghum breeding program. He actively participated in the project through experiment design, hybridization and selction. Dr. Morris Bitzer who cooperated on this project passed away in 2010; his knowledge of sweet sorghum production will be missed. TARGET AUDIENCES: The primary target audience is members of the National Sweet Sorghum Producers and Processors Association. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
Sorghum plant introductions 152771 and 208190 did not produce higher stem juice brix when in hybrid combination with sweet sorghum variety Dale. The higher juice brix identified in those plant introductions was not conditioned by dominant alleles that would have produced higher brix in the F1 hybrid. KN Morris continued to be adopted by sweet sorghum producers. For the second consecutive year the sorghum syrup which won the syrup quality contest at the National Sweet Sorghum Producers and Processors Association meeting was produced from KN Morris.

Publications

  • T.W. Pfeiffer, M.J. Bitzer, J.J. Toy, and J.F. Pedersen. 2010. Heterosis in Sweet Sorghum and Selection of a New Sweet Sorghum Hybrid for Use in Syrup Production in Appalachia. Crop Science 50:1788-1794.


Progress 01/01/09 to 12/31/09

Outputs
OUTPUTS: Although heterosis is well established in grain and forage sorghum [Sorghum bicolor (L.) Moench], reports of heterosis in sweet sorghum are limited to results from grain sorghum x sweet sorghum hybrids. Recent development of cytoplasmic male sterile sweet sorghum lines allows creation of sweet sorghum hybrids for research and commercial applications. Such male sterility may also affect the allocation of photosynthate to different plant parts creating the potential increase of sugar content in sweet sorghum stems by eliminating seed as a carbohydrate sink. For this application, A3 cytoplasmic male sterility has strong potential for eliminating seed set. We compared the performance of A3 cytoplasmic male sterile lines and A3 cytoplasmic male sterile hybrids to fertile B3 counterparts and to each other. A3 cytoplasmic male sterile Dale, Wray, and Sugar Drip, and N100 were crossed in all combinations to their male fertile counterparts to generate hybrids, resulting in 20 genotypes including the male fertile lines. The 20 genotypes were grown in a randomized complete block in two years at Lexington, Kentucky. 144 F4 derived lines were tested in two replications at Lexington. Lines were selected with a heading date earlier than (Simon + 7 days), a Brix > 16, lodging score < 2, and weight > Simon. 800 F4 lines from 400 F3 families were evaluated for low incidence of leaf disease, early heading, and low lodging. PARTICIPANTS: Nothing significant to report during this reporting period. TARGET AUDIENCES: Nothing significant to report during this reporting period. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
Male sterile hybrids and lines had higher brix than male fertile lines. Hybrids produced greater stalk yield due to taller plants with greater stem diameter. Juice fraction and juice composition remained relatively unchanged. Only six hybrids showed positive heterosis for brix. The greater juice yield and higher sugar content of selected hybrids such as A3 N100 x Dale could produce more total syrup or ethanol than current pureline sweet sorghum varieties. Plot weights ranged from 10.2 kg to 25.2 Kg. Brix ranged from 10 to 22. 21 early lines were advanced for further testing. 144 F4 plants were selected for testing in 2010.

Publications

  • No publications reported this period