Author
Farnham, Mark |
Submitted to: HortScience
Publication Type: Abstract Only Publication Acceptance Date: 5/22/2008 Publication Date: 7/15/2008 Citation: Farnham, M.W. 2008. Glossy and Nonglossy Near-Isogenic Lines of Broccoli Derived from Dihaploids. HortScience. 43:1219. Interpretive Summary: Not required. Technical Abstract: The broccoli breeding and genetics project at the U.S. Vegetable Laboratory (USVL) has developed a large number of dihaploid lines of broccoli using anther or microspore culture. Typically, the lines that result from the culture processes are highly uniform and can be presumed to be highly homozygous, as is expected with dihaploids. However, occasional dihaploid lines exhibit variants that usually do not become evident until the R1 generation (i.e., first generation from seed). The most common variant observed is a plant with glossy leaf type. By selecting and selfing glossy leaf variants and nonglossy (wild type) plants from the same line, it has been possible to develop paired lines that appear nearly identical except for the glossy leaf trait. DNA marker analysis has verified that the paired lines can be considered near-isogenic lines for the glossy leaf trait. In all cases observed to date, the glossy leaf trait appears to be controlled by a recessive gene although tests have not been conducted to determine if the glossy variants occur due to allelic changes at the same locus or different loci. Two pairs of near isogenic lines for glossy leaves are being increased for release by ARS. One pair of lines is derived from a dihaploid regenerated from an anther culture of the commercial hybrid ‘Marathon’ and these lines are designated USVL050 and USVL051. The other pair is derived from a dihaploid regenerated from an anther culture of a USVL F1 and they are designated USVL115 and USVL116. These two pairs of broccoli lines that are near-isogenic for leaf glossiness should prove useful tools for studying the effects of this leaf characteristic on insect behavior or predation as well as other things that might be impacted by this character associated with leaf waxiness. |