Consumer demand for Triticale cultivars as a winter forage crop in Korea has been increasing because of its ability for high and stable yield. However, more than 10 years are required to develop new varieties with conventional breeding programs. A speed breeding system using long-day photoperiodic treatment has recently been suggested and applied in wheat and barley, but not in the triticale breeding program in Korea. To evaluate the availability of the established speed breeding system for triticale breeding programs in Korea, we used nine domestic triticale cultivars to investigate their growth characteristics under a 22 h photoperiod. The average days to heading (DTH) of the nine cultivars was 38 days, and Gwangyoung and Minpung showed the most delayed DTH at 42 days. Therefore, all nine triticale cultivars were able to shorten the growth duration under the tested photoperiod condition. One productive tiller and more than 10 seeds were obtained from each cultivar. The germination percentage was over 82% when the spikes were harvested 20 days after heading, dried, and chilled for a week to break dormancy. These results suggest that in Korea, the rapid generation advancement system with simple long-day photoperiodic treatment can be applied to triticale breeding programs to reduce the breeding time.

A speed-breeding system using photoperiod characteristics has recently been developed to reduce the entire growth period in wheat. In this study, the entire growth period of four Korean varieties was examined to investigate whether this speed-breeding system would be beneficial for our wheat breeding program. When four varieties were cultivated under a 22-hour light/2-hour dark cycle in a glasshouse, the number of days to heading of Jokyoung and Baekkang was 44 and 43, respectively, and the number for Keumgang and Joongmo2008 was more than 75. Around twelve seeds per plant were obtained from Jokyoung and Baekkang, and the seeds of these varieties completely germinated when harvested at 20 days after heading. These results suggest that this speed-breeding system can be a reliable method of reducing the growth period in Korean wheat breeding.