Bulb-type onion introgressants posessing Allium fistulosum L. genes recovered from interspecific hybrid backcrosses between A-cepa L. and A-fistulosum L.

Allium fistulosum possesses a number of traits which would be desirable in A. cepa. Thus far, no commercial A. cepa cultivars have been released which harbor Allium fistulosum traits. F1BC3 populations were generated for this study by backcrossing A. cepa to A. cepaxA. fistulosum hybrids. The F1BC3 plants were evaluated for plant morphology, floral characters, male-sterile cytoplasm, soluble solids and pungency, and isozymes. Overall growth habit and floral characters of the F1BC3 plants were much like A. cepa. We repor t here the recovery of recombinant, bulbing, and fertile A. cepa-type onion s that exhibit A. fistulosum isozyme alleles and morphological markers. Rec ombination between A. cepa and A. fistulosum genomes was achieved using the introgression strategy of backcrossing A. fistulosum into A. cepa, thereby ameliorating the nuclear cytoplasmic barriers that occurred in previous le ss successful introgression attempts when plants were not in A. cepa cytopl asm. We believe this report to be the first demonstration of onion introgre ssants that are like A. cepa in appearance, are male- and female-fertile, a nd possess A. fistulosum genes.