Submitted to: Soybean Research World Conference Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: November 22, 2003
Publication Date: February 29, 2004
Citation: Nelson, R.L., Guzman, P.S., Neece, D.J. 2004 QTL associated with seed protein concentration from three sources high protein. [abstract]. Abstracts of contributed papers and posters. VII World Soybean Research Conference. Foz do Iguassu, PR, Brazil. P. 56. Technical Abstract: Protein accounts for approximately 40% of the dry matter and nearly three-fourths of the value of the soybean seed. Protein concentration in most commercial soybean cultivars has not increased over the past 60 years of soybean breeding in the U.S. primarily because of the negative relationship between protein concentration and seed yield. Identifying specific loci that influence protein concentration will be important in understanding the genetic relationship between protein concentration and seed yield. Determining the genetic variation among sources of high protein may be critical for efficiently increasing the level of protein concentration. The objectives of our research were to identify QTL associated with seed protein concentration and determine if these loci were different among three sources of high protein: HHP, L69-183, and PI 82278. HHP is a high protein experimental line with an unknown G. soja accession as the source of high protein. The high protein parent of L69-183 was Sioux introduced from Hokkaido, Japan, in 1929. PI 82278 was introduced from Korea in 1929. Each source of high protein was crossed to the cultivar Williams and high protein F4 lines were selected. These lines were crossed to Williams 82, a backcrossed derived line from Williams with the Rps1k allele for Phytophthora rot resistance, and high protein F5 lines were selected. These selected lines were backcrossed to Williams 82 and individual F2 plants were harvested to create 120 random BC2F3 lines from each donor parent. The random lines plus the parents were grown in 2 replications at 3 locations for 2 years. The protein concentrations of the donor parents of the final backcrosses were 474, 496, and 503 mg g-1 dry matter for the Sioux, G. soja, and PI 82278 sources, respectively. The protein concentration of Williams 82 was 437 mg g-1 dry matter. The range in protein concentration in the three populations of experimental lines varied from 51 to 69 mg g-1 dry matter. Approximately 100 SSR loci were polymorphic between the donor and recurrent parents. Each line will be genotyped using the polymorphic SSR markers. Markers linked to loci affecting protein concentration will be identified.