Stress treatments influence efficiency of microspore embryogenesis and green plant regeneration in hexaploid triticale (× Triticosecale Wittmack L.)

Doubled haploid (DH) production is a key technology in plant breeding and research. One emerging method of choice for DH production is microspore culture, which requires reprogramming of the microspores from their normal gametophytic development to a sporophytic development resulting in embryo formation. This commonly requires the application of stress such as cold, heat, or starvation. Here, we report the effect of different stress treatments on embryo formation and the proportion of green plants in triticale microspore culture. We observed different responses to the applied stress treatments among three studied genotypes. In general, a 3-wk cold stress treatment performed best with regard to the two criteria. For one genotype, the application of a 24- or 48-h heat stress gave similar or slightly better results and consequently may be an alternative for genotypes that are recalcitrant to the cold stress treatment.