Submitted to: American Society of Agronomy
Publication Type: Other
Publication Acceptance Date: 7/20/2002
Publication Date: 10/15/2002
Citation: Santos, A., Jellen, E.N., Livingston, D.P., Murphy, J.P. 2002. A cytological marker for crown freeze resistance in oat.. American Society of Agronomy.
Interpretive Summary: A piece of a chromosome that can be visualized using traditional cytogenetics has been shown to trade places with a portion of another chromosome. In studies involving progeny of a cross between a winter-tender cultivar which does not trade chromosome pieces with a winter hardy cultivar which does exchange pieces, we found that a significant relationship existed between freezing tolerance and the exchange of chromosome pieces. This suggests that traits which govern freezing tolerance are very close to the portion of the chromosome which trades places and it may be possible to select freezing tolerant individuals on the basis of whether it has the switched chromosome pieces. This will save many generations of work and could allow the release of new cultivars in about half the time it takes using conventional breeding.
Technical Abstract: Variation in the presence of an intergenomic translocation segment on hromosomes 7C and 17 of common cultivated oat (Avena sativa L.) and red oat (Avena byzantina K. Koch) has been shown by previous studies. Translocations are known to get fixed in populations when they place genes conferring a collective adaptive advantage into common linkage group. Regions on one or both chromosomes 7C and 17 have been implicated as affecting plant height, maturity, and vernalization. The objective of this study was to determine associations between crown freeze resistance and the presence of the 7C-17 translocation. Ninety-five recombinant inbred lines (RILs) developed by crossing Fulghum (A. byzantina type, no translocation, less winter-hardy) with Wintok (A. sativa type, has translocation, winter-hardy), were used in the study. Crown freeze resistance was scored following the scale 0 - 5, where 0=dead and 5=alive. Linear regression was used to determine linkage. The association was highly significant (P=0.001) with an R[SQUARED] of 23.6%. The results suggest that the 7C-17 translocation can be used a a marker for crown freeze resistance.