IV.5 Reports from coordinators: Translocations and balanced tertiary trisomics.
R. T. Ramage. Department of Agronomy and Plant Genetics, University of Arizona, Tucson, Arizona 85721, USA.
During 1974, letter designations were assigned to 256 translocations obtained by Gunborg and Arne Hagberg, The Swedish Seed Association, Svalof, Sweden. They are listed in Table 1.
Two multiple translocation stocks were obtained from N. A. Tuleen, Texas A & M University, College Station, Texas, USA. One stock combines the two translocations T3-7c and T3-7d. The translocated chromosomes in the combined stock consist of a centromere segment of one of the chromosomes and end segments of the other chromosome, i.e., 77733303333777 and 33377707777333. The other stock is homozygous for Tl-5v + T2-6Y + T3-7d. In this stock, all of the translocated chromosomes have distinctive morphologies making it very easy to recognize chromosome 4.
A tertiary trisomic with an extra T2-7c chromosome and balanced for the male sterile gene, msg2, has been established and added to the World Collection (Fastnaught and Ramage, BGN 5: 9).
Three balanced tertiary trisomics with extra T27d chromosomes and containing normal chromosomes carrying recessive msg2 and albino seedling alleles very closely linked have been established (Ramage and Jones, BGN 5: 44-45). The three albino seedling alleles have not yet been allele tested. The three lines may comprise, one, two or three different BTT's. As soon as allele tests are completed, all different ones will be added to the World Collection.
Limited amounts of seed of the translocations and balanced tertiary trisomic seed stocks are available upon request.
Table 1. Translocations added to the World Collection in 1974:
T1-2q to T1-4ac (page 78)
T1-5q to T1-7z (page 79)
T1-7aa to T2-7v (page 80)
T2-7w to T3-6v (page 81)
T3-7l to T4-7m (page 82)
T4-7n to T6-7ap (page 83)
