Location: Soybean and Nitrogen Fixation Research
2012 Annual Report
For Objective 2: We have developed a breeding line, G03-3666, with 32 g/kg of cysteine + methionine. Year 1: We will select lines with G03-3666 alleles at the four sulfur-containing amino acids QTLs. In addition we have crossed G00-3213 with the BC5 line Haskell containing the Lg-I high protein allele from Danbaekkong and the Lg-N and Lg-L low phyate alleles from CX1834-1-2. We will pyramid the high protein allele from Danbaekkong, the low phytate QTL alleles from CX1834-1-2, and the high sulfur-containing alleles from G03-3666 into G00-3213. This will be achieved by the development of two parallel backcross populations, one backcross population to incorporate the Lg-I high protein allele from Danbaekkong and Lg-N and Lg-L low phytate alleles from CX1834-1-2 into G00-3213 and the other backcross population to incorporate the elevated sulfur-containing amino acid alleles from G03-3666 at the Lg-C2, Lg-O, and Lg-L QTLs into G00-3213. We will make the 1st and 2nd backcrosses. Year 2: Make the 3rd and 4th backcrosses. Year 3: Make the 5th backcrosses. Once the backcross 5 has been achieved for these two populations, we will cross the two backcross 5 populations to pyramid high protein, low phytate, and elevated sulfur-containing amino acids into the conventional G00-3213.
Data were analyzed from the Athens and Plains locations for the backcross-derived lines of Benning RR with the high protein and low phytate quantitative trait loci (QTL). The data were then combined across locations and analyzed. Two of the backcross 5 Benning RR lines containing the Lg-I high protein QTL (3.2 g/kg higher in protein than Benning RR) and the Lg-N and Lg-L QTL for low phyate (35% of the phytate as Benning RR) averaged 36.0 and 3.67 bu/a in yield compared to an average of 38.0 bu/a for Benning-RR. The yields were low in both the Athens and Plains locations due to the extreme heat during the summer of 2011. Also, crosses combining high sulfur amino acid QTL Lg-B2, Lg-C2, and Lg-G I –were made and F1 seed was planted in the 2012 winter greenhouse.