Biotech Updates

How to Boost Recovery of Fertile Doubled-Haploid Onions

June 22, 2007

Three strategies were described by Cornell University researchers to help maximize the recovery of fertile doubled-haploid (DH) onions and meet the needs of breeding programs for a large number of plants.

The strategies include 1) the use of whole basal explants from haploid plants treated with the anti-mitotic agents amiprofos methyl (APM) or oryzalin, (2) spontaneous and induced chromosome doubling in somatic regenerants from cultured flower buds, and (3) ploidy reduction through a second cycle of gynogenesis. Gynogenesis is development in which the embryo contains only maternal chromosomes.

Onion breeders may benefit from these strategies by being able to recover diploid plants and minimizing losses of gynogenic plants due to ploidy-related complications. The researchers further recommend the application of 100 to 150 mM APM to whole basal explants is an excellent initial step toward recovery of DH materials.

The paper published in Plant Science can be accessed by subscribers at http://dx.doi.org/10.1016/j.plantsci.2007.03.010.