Submitted to: HortScience
Publication Type: Abstract Only
Publication Acceptance Date: June 1, 1998
Publication Date: N/A
Technical Abstract: Anther and microspore culture are commonly used to produce doubled-haploid (DH)lines in broccoli. It is well documented that DH regenerants are produced by means of polyploidization during anther culture. However, polyploidization may not occur at all, or it may involve a tripling or quadrupling of the chromosome complement. As a consequence, regenerated populations from anther culture contain diploids, but also haploids, triploids, and tetraploids. Microspore culture represents a simpler and more direct method for producing DHs. Although a similar mix of ploidy types is likely to be observed among regenerants derived from microspore culture, the actual ploidy levels of such regenerants have not been documented for broccoli. Thus, the objectives of this study were to compare ploidy levels of regenerants developed using both anther and microspore culture, and to examine phenotypic variation in ploidy makeup of populations developed from both anther and microspore culture using different F1 hybrids. Broccoli regenerants were derived simultaneously from both culture processes using four F1 hybrids, including Everest, Patriot, Greenbelt and Major. On avaerage, 90% of regenerants from anther and microspore cultures were determined to be diploids or tetraploids. Differences in ploidy makeup of populations were observed among hybrids for both culture techniques. Regardless of the method used, 'Everest' produced a greater percentage of diploids and a lower percentage of tetraploids than 'Patriot' did. Haploids were observed more frequently from microspore culture than from anther culture when 'Everest' and 'Major' served as parents.