Submitted to: Crop Production and Protection Conference Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: 8/7/2000
Publication Date: N/A
Technical Abstract: Our lab has developed a set of oat-maize addition lines (OMALs) that carry individual maize chromosomes. The process involves crossing hexaploid oats with maize, with partial elimination of maize chromosomes at early embryo stages followed by embryo rescue. Disomic addition lines for maize chromosomes 1, 2, 3, 4, 6, 7, and 9 have been produced through meiotic restitution. A monosomic chromosome 8 addition line transmits its maize chromosome to 8% of its progeny. Maize chromosomes 5 and 10 are present in haploid plants; colchicine treatment is being used to produce disomic lines. OMALs were shown to be an efficient means for mapping sequences to chromosome by mapping umc and csu marker sequences that had previously been mapped by Southern blots. We are in the process of mapping EST sequences from the Zea mays DataBase (www.zmdb.iastate.edu) to chromosome. Of the first 100 sequences mapped, 75 map to a single chromosome, 22 map to 2 chromosomes, and 3 map to more than 2 chromosomes. Once located to chromosome, these sequences may be more precisely mapped using a set of radiation hybrid lines. Radiation hybrid lines are produced by irradiating OMALs. Maize chromosomes are fragmented by radiation treatment, and radiation hybrid lines carrying pieces of the maize chromosome are recovered. Linkage relationships are determined by the probability of any two markers being present together in a particular radiation hybrid line. Our goals for this work include developing high resolution radiation hybrid maps for each maize chromosome, mapping large numbers of sequences, and making available addition line and radiation hybrid DNA sets for use by the maize research community. This material is based upon work supported by the National Science Foundation under Grant No. 9872650.