Submitted to: Pisum Genetics
Publication Type: Peer reviewed journal
Publication Acceptance Date: 10/24/2005
Publication Date: 12/30/2005
Citation: Coyne, C.J., Grusak, M.A., Razai, L. 2005. Variation for pea seed protein concentration in the usda pisum core collection. Pisum Genetics. 37:7-11. Interpretive Summary: Legumes are the main source of protein for human and animal consumption worldwide. While cereals supply nearly 50% of the protein in the human diet, an unfavorable balance in amino acids (poor in lysine) requires complementary protein sources (12). Legumes are good complements to cereals, as they are rich in lysine, but poor in sulfur containing amino acids (methionine and cysteine) (12). In this study, we characterized the total seed protein concentration of 480 accessions from the USDA Pisum core collection. These accessions may aid in the future discovery of useful alleles for breeding enhanced seed protein levels in this crop, or could prove valuable for mapping novel regulatory genes associated with increased seed protein concentration in pea.
Technical Abstract: Seed protein concentration (N x 5.44) was determined using a Leco nitrogen analyzer for 480 accessions in the USDA Pisum core collection. Protein varied over two-fold in the accessions tested. The seed used in this study was grown under controlled conditions, which should significantly reduce the large effect environment can have on pea seed protein content. Protein concentration varied over 2.5 -fold in the accessions tested with the highest percentage of 30.93% and lowest of 12.38 % in the accessions tested. This range is in agreement with the literature of 34.1% to 14.5% for Pisum sativum seed who used a higher N to protein conversion factor of 6.25 (Savage and Deo, 1989). A comparison of the seed size (100 seed weight in g) and seed protein concentration was conducted, and no correlation was found for the USDA Pisum core (r=0.01). Thus, it appears that seed protein concentration can be enhanced independently of yield and/or seed size in pea. The complete data set and accessions are available through the internet (http://www.ars-grin.gov/npgs/)