Registration of Four Pairs of Soybean Near‐Isogenic Lines, BARC‐14 to BARC‐17, Nodulated vs. Nonnodulated

Four pairs of soybean [Glycine max(L.) Merr.] near-isogenic lines, BARC-14 to BARC-17, nodulated vs. nonnodulated (Reg. no. GP263 to GP-270, PI 602447 to PI 602454). were developed by the USDA-ARS at Beltsville, MD, and released in 1996. The pairs of near-isogenic lines were derived from 1986 crosses between 'Clark' rj, (1) and the recurrent parent high-protein lines D76-8070 (2) and CX797-21 (3) and the determinate cultivars 'Essex' (4) and 'Ripley' (5), which are BARC-14 to BARC-17, nodulated vs. nonnodulated, respectively. These isogenic pairs should be useful for determining absorbed vs. fixed N content of the plant and for basic research in N, protein, and amino acid metabolism in soybean. The four pairs of isolines were developed by maintaining heterozygosity at the /?/', locus (6) while inbreeding occurred at all other loci. The F, plants from the recurrent parents x Clark rj\ were backcrossed three times to the recurrent parents and sufficient BC3F, seed was created to ensure the retention of the r/\ gene in the BC3F2. In 1990, BCjF, seed were advanced and seed from the single plants were planted in BC3F2 progeny rows the following year. Single, nodulated plants from rows segregating for nodulation, phenotypically similar to the recurrent parents, were selected and planted in individual plant rows in 1992. Two subsequent cycles consisted of selfing and selecting single, nodulated plants from segregating rows that were phenotypically similar to the recurrent parent. Selected plants were planted in individual plant rows in the following years. In 1994, individual nodulating and