Efficient Production of Spontaneous and Induced Doubled Haploid Triticale Plants Derived from Anther Culture

In a test of the efficiency of various methods of chromosome doubling among several genotypes of hexaploid triticale (x Thticosecale Wittmack), 506 green plants from seven hybrid triticales were obtained from 15104 cultured anthers with the efficiency ranging from 0.4 to 7.2 plants/100 anthers for different genotypes. Flow cytometry of the leaf nuclear DNA content showed that among those 506 green regenerants, 215 (42.5%) were haploid and 291 (57.5%) were diploid, presumably spontaneously doubled haploids. The haploids were treated with a colchicine solution in four different regimes and 128 doubled haploid lines were obtained, for 59.9% efficiency of chromosome doubling. The best doubling rate was observed when plants were treated with colchicine solution on the regeneration medium in the tubes and cooled for 10 days at 8°C in 16/8 h light/dark. Assuming that all regenerated diploid plants were spontaneously doubled haploids, the overall efficiency of doubled haploid production was very high, ranging from 66.7 to 90.7% among the green regenerants from different genotypes.