Flower bud differentiation by temperature and photoperiod was investigated in early-, medium-, and late-maturing cultivars of radish (Raphanus sativus L.). Flower bud differentiation was induced by only day-length extension treatment (18 hr light/day) in early - and medium-maturing cultivars. Therefore, the early- and medium-maturing cultivars of radish were advanced the time of the flowering by the 2 weeks low temperature duration with day-length extension (18 hr light/day). The vegetative growth of early- and medium-maturing cultivar was the best by only day-length extension (18 hr light/day). However, late-maturing cultivar was needed for the flower bud differentiation and optimal vegetative growth not only long-day but also low temperature during 4~6 weeks at least. Our results suggest the optimal condition for flower bud differentiation in the each early-, medium-, and late-maturing cultivars of radish, which will be useful to develop breeding materials of radish.

A rice variety ‘Dabo‘ is a japonica rice (Oryza sativa L.) with good eating quality, lodging tolerance, and resistance to rice stripe virus (RSV) and blight bacterial disease(BB). It is developed by the rice breeding team of Yeongdeog Substation, National Institute Crop Science, RDA in 2012. This variety derived from a cross between ‘Yeongdeog31’ with good plant type and ‘Milyang165’ with good eating quality conducted in 2001/2002 winter season. A promising line, YR23160-31-2-1-5-B-3, selected by pedigree breeding method was designated as the name of ‘Yeongdeog53’ in 2009. After the local adaptability test was carried out at seven locations from 2010 to 2012, ‘Yeongdeog53’ was released as the name of ‘Dabo’ in 2012. ‘Dabo’ is short culm length as 69 cm and medium-growth duration. This variety is resistant to races, K1, K2, and K3 of bacterial blight and stripe virus and moderately resistant to leaf blast disease. ‘Dabo’ has translucent and clear milled rice kernel without white core and belly rice, and good eating quality as a result of panel test. The yield potential of ‘Dabo’ in milled rice is about 5.90 MT/ha at ordinary fertilizer level of local adaptability test. This cultivar would be adaptable to south plain, east-south costal area, and south mid-mountainous area.

A rice variety ‘Daebo’ is a japonica rice (Oryza sativa L.) with good eating quality, lodging tolerance, and resistance to rice stripe virus (RSV) and blight bacterial disease (BB). It is developed by the rice breeding team of Yeongdeog Substation, National Institute Crop Science, RDA in 2011. This variety derived from a cross between ‘YR21247-68-1’ with good plant type and ‘Yeongdeog35’ with good eating quality conducted in 2002 summer season. A promising line, YR23940-B-17-1-2, selected by bulk and pedigree breeding method was designated as the name of ‘Yeongdeog51’ in 2008. After the local adaptability test was carried out at seven locations from 2009 to 2011, ‘Yeongdeog51’ was released as the name of ‘Daebo’ in 2011. ‘Daebo’ is short culm length as 63 cm and medium-growth duration. This variety is resistant to races, K₁, K₂, and K₃ of bacterial blight and stripe virus and moderately resistant to leaf blast disease resistance. ‘Daebo’ has translucent and clear milled rice kernel without white core and belly rice, and good eating quality as a result of panel test. The yield potential of ‘Daebo’ in milled rice is about 5.93 MT/ha at ordinary fertilizer level of local adaptability test. This cultivar would be adaptable to middle plain, south plain, mid-west costal area, and south mid-mountainous area.