Using Marker Assisted Selection to Identify Top Performing Soybean Recomninant Inbred Lines.

A total of 939 recombinant inbred lines (RIL) of Essex x Williams 82 were screened using >50,000 SNPs and 17,232 polymorphic SNPs were identified. To conduct phenotypic evaluation, genotypes were grown in Knoxville, TN during Year 1 and protein content was detected using near infrared (NIR) spectroscopy. ANOVA identified significant differences among RIL for protein content (p = 0.05). Protein QTL were detected from the Year 1 data using R/qtl, (Broman, 2009). In 2013, a subset of 302 Group V RIL were grown in three location across the state of TN in a randomized block design (RBD). Protein and oil content were determined using near infrared NIR spectroscopy. In Year 1, four QTL associated with protein content were identified. A QTL located on Gm 13 (183 cM), explained 4.1% of protein variation, additive effects of three additional QTL explained a total of 7.2% of the variation for seed protein. In year 2 the QTL located on Gm 13 (205 cM), explained 5.8% of the variation of additional QTL accounted for 7.7% of protein variation. A total of 4 QTL were identified in Year 2, however one QTL on Gm 9 was not present in Year 1 and a QTL on Gm 14 was absent in the second year. Some QTL were unstable across environments. Our next goal will be to demonstrate the usefulness of protein QTL for marker assisted selection to improve soybean protein content.