Genetic improvement for yield in soybean [Glycine max (L.) Merrill] has beenaccomplished by breeding within a narrow elite gene pool. Plant introductions (Pis) may be useful for obtaining additional increases in yield if unique and desirable alleles at quantitative trait loci (QTL) can be identified. The objectives of the study were to identify QTL for yield in elite and PI germplasm and to determine if the Pis possessed favorable alleles for yield.Allele frequencies were measured with simple sequence repeat (SSR) markers in three populations that differed in their percentage of PI parentage. AP10 had 40 PI parents, API 2 had 40 PI and 40 elite parents, and API 4 had 40 elite parents. Four cycles of recurrent selection for yield had been conducted in the three populations. Nei's genetic distance indicated that AP10, AP12, and AP14 remained distinct through cycle 4 (C4), but that the genetic diversity narrowed within each population. Less gametic phase disequilibrium (GPD) was observed in the parents used to form the cycle 0 (CO) populations than in C4 of AP12 and AP14. Allele frequencies of the highest-yielding C4 lines in the three populations were compared with the parents used to form the populations of the initial cycles. Allele flow was simulated to account for genetic drift. Ninety-two SSRs were associated with 56 yield QTL. Nine of the QTL had been identified in previous research. Thirty-three favorable marker alleles were unique to the PI parents. The restriction of alleles from the 40 CO parents to the 20 cycle 1 (CI) parents of AP10 was reflected in the number of alleles that had frequency changes and could explain the reduced genetic variance for yield in the C4 of AP10. Genetic asymmetry may account for the different genetic gain for yield that had been observed between AP10 and AP14.

Quantitative trait loci have been identified through associations with changes in molecular marker allele Genetic improvement for yield in soybean [Glycine max (L.) frequency in recurrent selection populations. Stuber et Merr.] has been accomplished by breeding within a narrow elite gene al. (1980) found that allele frequency changes at eight pool. Plant introductions (PIs) may be useful for obtaining additional isozyme loci in maize (Zea mays L.) agreed with yield increases in yield if unique and desirable alleles at quantitative trait loci (QTL) can be identified. The objectives of the study were to

Here, we report the genome sequence of Magnetospirillum magnetotacticum strain MS-1, which consists of of 36 contigs and 4,136 protein-coding genes.