Submitted to: Maize Genetics Conference Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 3/15/2001
Publication Date: 3/15/2001
Citation: WEBER, D., SCHNEERMAN, M., BREWBAKER, J., MING, R., MCMULLEN, M.D., BOWEN, B., BEAVIS, B., SCHUNK, C., CORGLIANO, D., WHITEHURST, B. USE OF RECOMBINANT INBREDS TO IDENTIFY QTL CONTROLLING GENETIC RECOMBINATION IN MAIZE. MAIZE GENETICS CONFERENCE. 2001. ABSTRACT. P. 114. Interpretive Summary:
Technical Abstract: Previously (Weber et al. 1999, 41st Maize Conference Proceedings, p24), we compared recombination frequencies in 11 pairs of parents of recombinant inbred lines (RIs) that had been or were being mapped using molecular markers. Each parent was crossed with inbred testers that possessed linked morphological markers on chromosome 5 (a2 bt1 pr1), 7 (o2 v5 gl1) or 9 (yg2 2sh1 wx1). The F1s were reciprocally testcrossed, and the testcross ears were classified to determine recombination frequencies associated with these lines. We found that the parents of one set of RIs (Hi31 and Ki14) from Brewbaker's laboratory displayed the greatest recombinational differences. RIs from these parents were generated by Brewbaker's group and were mapped at 127 RFLP loci by Ming and McMullen. The RIs from these parents that had already been mapped using molecular markers were provided by Brewbaker's laboratory. Each of the RIs was crossed to the extent possible with the inbred testers for chromosomes 5, 7, and 9. The F1s wer testcrossed, and the progeny produced are being classified. This report describes the analysis of the a2-bt and bt-pr regions on chromosome 5. Using Qgene and 91 RIs from these parents, we identified a QTL that impacts recombination in the a2-bt interval on chromosome 5 that is near the a2-bt1 interval. This QTL could be a gene(s) that impacts recombination in this region or the recombinational difference could be due to structural heterozygosity in this region in the Hi31 and Ki14 parents. We also analyzed recombination in the bt1-pr1 region in 47 RIs from these parents and did not detect any QTLs that affect recombination. Fewer RIs could be analyzed for this interval because the Ki14 parent was pr/pr and only about half of the RIs contained the dominant allele of this locus.