Progress 04/01/05 to 03/31/08
Outputs
Progress Report Objectives (from AD-416) Develop soybean varieties with higher protein and lower phytic acid concentrations, and agronomic performance similar to cultivar Boggs, Haskell, Benning, and Cook. Approach (from AD-416) Map the location of genes associated with protein concentration and phytic acid content. Apply DNA marker selection methods to introgress a major gene fro increased protein concentration (+4.5% protein) that is not associated with a reduction in seed yield into maturity group VI, VII, VIII soybean varieties with resistance to cyst nematode and southern root-knot nematode. Significant Activities that Support Special Target Populations This project is related to Objective 2 of this in-house project: To characterize the biological mechanisms that control phytic acid concentration in soybean seed, and determine the impact of genetically lowering phytic acid on seed and seedling vigor, soy protein functionality and soybean meal digestibility. Marker-assisted selection was used to transfer a gene at a major protein quantitative gene trait locus (QTL) on Lg-I from the high protein South Korean variety Danbaekkong to three elite Roundup Ready (RR) varieties Benning RR, Haskell RR, and Prichard RR. When tested across six field environments the gene increased protein from 38.7% to 42.7% in Benning RR, from 39.1% to 42.0% in Haskell RR, and 40.3% to 44.8% in Prichard RR. The high-protein Benning RR lines yielded 6% less than the normal-protein Benning RR lines. The seed yield of the normal- and high-protein Prichard RR and Haskell RR did not differ. It was determined that three backcrosses to Prichard RR, Benning RR, and Haskell RR eliminated the low seed germination and vigor associated with the low phytate trait in CX1834-1-2. The low-phytate and normal- phytate near-isolines of Haskell RR and Benning RR were equal in seed yield. An initial amino acid QTL mapping was conducted in a population of 150 recombinant inbred lines from the cross of Benning x Danbaekkong and 10 QTL on 10 different linkage groups were identified to be associated with lysine, sulfur-containing amino acids (methionine + cysteine, and threonine (the amino acids were measures as a percent of total protein). Five of these amino acid QTL were associated with a total protein QTL (Lg- I, Lg-E, LG- C2, Lg- K, and Lg-B2). The largest protein QTL on Lg-I (explaining 43% of the variation in total protein content) was also associated with the sulfur-containing amino acids and threonine. The protein QTL on Lg-E and Lg-C2 each explained 6% of the variation. The QTL on Lg-E was associated with the sulfur-containing amino acids and with threonine, while the QTL on Lg-C2 was associated with lysine and threonine. The protein QTL on Lg-K and Lg-B2 each explained 4% of the variation. Both of these QTL were associated with sulfur-containing amino acids and with lysine, and threonine. However, for five of the 10 amino acid QTL, the amino acid QTL was not associated with a total protein QTL. For the sulfur-containing amino acids, there were QTL on Lg- G and Lg-C1 which each explained 5% of the variation. Three other QTL were associated with lysine content and were located on Lg-G, Lg-B1, and Lg-D1a. These QTL explained between 6% and 7% of the variation in lysine content. These five QTL are important because they indicate that we can increase amino acid content as a percentage of total protein in this population without increasing total protein (increased protein quality without having to decrease protein content). The Authorized Departmental Officer's Designated Representative monitored activities of project through frequent phone calls and emails, two formal meetings, site visits, and through quarterly reports.
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Progress 10/01/06 to 09/30/07
Outputs
Progress Report Objectives (from AD-416) Develop soybean varieties with higher protein and lower phytic acid concentrations, and agronomic performance similar to cultivar Boggs, Haskell, Benning, and Cook. Approach (from AD-416) Map the location of genes associated with protein concentration and phytic acid content. Apply DNA marker selection methods to introgress a major gene fro increased protein concentration (+4.5% protein) that is not associated with a reduction in seed yield into maturity group VI, VII, VIII soybean varieties with resistance to cyst nematode and southern root-knot nematode. Significant Activities that Support Special Target Populations This report serves to document research conducted under a specific cooperative agreement between ARS and the Agricultural Research Station, University of Georgia. Additional details of research can be found in the report for the parent project 6645-21000-026-00D, Physiological/biochemical mechanisms associated with genetic alteration of soybean quality and productivity. The SSR marker map of Benning x Danbaekkong and the amino acid data of 150 lines of this population was used to identify and map QTL conditioning differences in total sulfur- containing amino acids as a percent of crude protein. The analysis revealed three QTL on separate linkage groups. The QTL were located near Satt083 on LG-B2, Satt376 on LG-C2, and Satt496 on LG-I. The QTL on LG- I is in the same region as the major protein QTL in this population and the allele for incresase sulfur-containing amino acids as a percent of crude protein was inherited from Danbaekkong. For the QTL on LG-B2 and LG-C2 the allele for higher sulfur-containing amino acids was inherited from Benning. Field tests of low-phytate near-isolines of Benning RR and Haskell RR showed no significant differences between either Haskell RR or Benning RR versus their low phyate isoline in seed yield or days to maturity. The low phyate Benning RR isoline averaged 4 inches taller in plant height, similar lodging score, and 51 mg per seed greater seed weight than Benning RR, while the low phyate Haskell RR line was similar in height, more lodging susceptible (score of 3.3 vs. 2.4; where 1 = all plants upright and 5 = all plants prostrate), and averaged 22 mg per seed greater seed weight. Improved meal quality provided by these soybeans will increase the competitiveness of U.S. soybean producers in the global market and provide a better protein meal for domestic users. The ADODR monitored activities through quarterly progress reports, 1 meeting with researchers, emails and phone calls.
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Progress 10/01/05 to 09/30/06
Outputs
Progress Report 4d Progress report. This report serves to document research conducted under a specific cooperative agreement between ARS and the Agricultural Research Station, University of Georgia. Additional details of research can be found in the report for the parent project 6645-21000-025-00D, Fundamental mechanisms for genetic alteration of soybean quality and productivity. Data for yield, maturity, and seed protein and oil content of lines which carried either the high-protein gene on chromosome I or the normal gene carried by most soybean varieties were collected in field experiments. In a comparison, the Prichard-RR BC3 lines with either the high protein gene or the normal gene had similar yields, despite having a significantly different protein contents. In contrast, the mean yields for the Benning and Haskell backcrosses with the high protein gene were significantly lower than the yields from lines carrying the normal gene. This high protein gene has the
potential to increase protein without depressing yield in some soybean varieties. Improved meal quality provided by these soybeans will increase the competitiveness of U.S. soybean producers in the global market and provide a better protein meal for domestic users.
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Progress 10/01/04 to 09/30/05
Outputs
4d Progress report. This report serves to document research conducted under a specific cooperative agreement between ARS and the University of Georgia. Additional details of research can be found in the report for the parent project 6645-21000-025-00D, Fundamental mechanisms for genetic alteration of soybean quality and productivity. This project was initiated on April 1, 2005. It is too early to report any significant progress at this time.
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