A Cytological Marker Associated with Winterhardiness in Oat
- A. G. Santosa,
- D. P. Livingstonb,
- E. N. Jellenc,
- D. R. Wootend and
- J. P. Murphy *d
The intergenomic translocation T7C-17 occurs at different frequencies in fall- versus spring-sown hexaploid oat (Avena sp.) germplasm. The objectives of this experiment were to evaluate crown meristem freeze tolerance and winter field survival among 94 random F4–derived lines from the cross between the cultivars Wintok (T7C-17, winterhardy) and Fulghum (non-T7C-17, less winterhardy) and to examine the association between these winterhardiness traits and T7C-17. Crown meristem freeze tolerance was evaluated in a three-replicate randomized complete block design in controlled environment growth cabinets. Field survival was evaluated in a three replicate randomized complete block design at Laurel Springs, NC during the 1999–2000 season. Greater crown meristem freeze tolerance and greater winter field survival were associated with the presence of T7C-17. Lines heterogeneous for the translocation had similar levels of crown meristem freeze tolerance and field survival as lines homozygous for the translocation. Twenty-two percent of the variation in crown meristem freeze tolerance and 27% of the variation in field survival was accounted for by translocation status. The observed frequencies of translocation homozygotes and heterozygotes did not fit the expected frequencies for single factor segregation in the F4 generation. There were almost threefold as many homozygotes with the translocation as homozygotes without the translocation which indicated preferential selection for T7C-17 during inbreeding. Our results suggested that T7C-17 might be isolating, in terms of recombination, either a dominant allele or a group of loci conditioning winterhardiness in our population.Please view the pdf by using the Full Text (PDF) link under 'View' to the left.
Copyright © 2006. Crop Science Society of America