Production of wheat doubled haploids (Triticum aestivumL.) by wheat × maize crosses using colchicine enriched medium for embryo regeneration

Abstract

The effect of colchicine enriched culture media on embryo regeneration and the production of doubled haploid wheat plants in vitro were examined using two regeneration media enriched with 300 and 900 mg/ colchicine respectively and the results were compared with results from plants treated with colchicine after regeneration. Four German winter wheat varieties were pollinated with a pollen mixture collected from two sweet corn hybrids. The number of pollinated florets, caryopses, haploid embryos and regenerated plantlets were scored. In total 14,000 pollinated wheat florets produced 10,879 caryopses from which 2,704 embryos were excised; 1,288 embryos regenerated to plants and 958 plants survived till maturity. The regeneration of embryos to plants was influenced by the wheat varieties, the colchicine treatment and colchicine concentration. The percentage of doubled haploid plants varied depending on chromosome doubling technique, colchicine concentration and wheat variety. Plants were cultured till ripening and those with seed set were scored as doubled haploid plants. The highest percentage of doubled haploids per 100 cultivated embryos across the four varieties were scored for plants regenerated on colchicine free medium and treated thereafter in vivo with colchicine (30.6 %), followed by plants regenerated on medium enriched with 300 mg/l colchicine (19.9 %) and 900 mg/l colchicine (18.4 %)