As the market demand on functionality rice has been increasing, embryo rice in which embryo residue remains even after milling has come to comsumers’ attention because rice embryo contains several functionality components. Consequently, development of rice varieties for higher rate of embryo adhesion to grains after milling has become one of the breeding objectives for quality improvement. In this study, we observed embryo dent of 49 commercial varieties and analyzed the relationship between embryo dent and grain size and shape. Embryo dent of rice grains varied 0.27 (Keunnun)~0.59 (Daerip 1) mm. Varieties Jinbu, Jinbo, Heugseol, Obong, Unkwang, and Cheongnam showed relatively deeper embryo dent, suggesting that they will be applicable in breeding for embryo rice. Embryo dent was correlated positively with grain width (r=0.53**) and grain size(r=0.34*), and negatively with grain width/length ratio (r= -0.38**). Strategies for breeding embryo rice were discussed in relation to embryo dent, grain size and shape.

• Yunjoo Lee(Department of Plant Science, Plant Genomics and Breeding Institute, and Research Institute of Agriculture and Life Sciences, Seoul National University)
• Gileung Lee(Department of Plant Science, Plant Genomics and Breeding Institute, and Research Institute of Agriculture and Life Sciences, Seoul National University)
• Rihua Piao(Department of Plant Science, Plant Genomics and Breeding Institute, and Research Institute of Agriculture and Life Sciences, Seoul National University)
• Sunmi Jang(Department of Plant Science, Plant Genomics and Breeding Institute, and Research Institute of Agriculture and Life Sciences, Seoul National University)
• Hee-Jong Koh(Department of Plant Science, Plant Genomics and Breeding Institute, and Research Institute of Agriculture and Life Sciences, Seoul National University) Corresponding Author