The auxins centrophenoxine and 2,4-D differ in their effects on non-directly induced chromosome doubling in anther culture of wheat (T. aestivum L.)

Doubled haploid technologies have become key tools for plant breeding. Using these techniques, the speed and efficiency of plant improvement processes can be significantly enhanced. Anther culture-based technologies have the potential to regenerate large numbers of doubled haploid plants without colchicine treatment. In an attempt to elucidate the influence of phytohormones on non-directly induced chromosome doubling, two synthetic auxins, 2,4-D and centrophenoxine, were tested in a wheat anther culture approach. Whereas the induction of androgenic embryo-like structures (ELSs) was efficient for both auxins, we observed a significantly higher frequency of chromosome doubling when using 2,4-D than when using centrophenoxine. When 2,4-D was added to the induction medium, a positive correlation between the size of ELSs and their ploidy level was detected by flow cytometry. The morphological selection of ELSs, a process that was included in routine operations of the method without significantly extending the input of time and effort, facilitates the production of fertile DH plants with a frequency of 60 %. Our findings may contribute to a more efficient production of doubled haploid wheat plants using a colchicine-free anther culture approach.