Since the first development of the high-yield variety ‘Tongil’ that led to the self-sufficiency of rice production in Korea, plant architecture has improved steadily to increase yield components. The purpose of this study was to analyze the chronicle shift of agronomic traits of high-yield rice, to provide future breeding goals. The culm length increased sharply from 65 cm in the 1970s to 80 cm in the 1990s, and then decreased slightly to 77 cm in the 2010s. The panicle length increased continuously from 22.8 cm in the 1990s, to 24.3 cm in the 2010s. The average number of seeds per panicle increased from 118 in the 1970s, to 142 in the 1990s, and decreased continuously to 119 in the 2010s. The ripening ratio increased from 75% in the 1970s to 83% in the 1980s, and decreased to 77% in the 1990s and after that, held steady at 85%. Thousand-grain weight was lowest in the 1980s at 20.9 g and sharply increased to 25.8 g in the 1990s, and decreased continuously to 23.3 g in the 2010s. The production of high-yield varieties increased significantly from the 1970s from 510 kg/10a to 769 kg/10a in the 2010s.

This study compared and analyzed the consumption and amount of red pepper used in Baechu Kimchi (cabbage Kimchi) especially the amounts used in Kimchi recipes with respect to the passage of time from the 1930s to the 2010s. In this analysis, 78 recipes for cabbage Kimchi were taken from books, daily newspapers and magazines from 1930 to 2014 and collected for comparison. The result of the study showed that the consumption and inclusion of dried red pepper powder in cabbage Kimchi increased. The average consumption of red pepper in the 1930s was 5.75 g, and the number went up to 8.83 g in the 1940s, to 13.8 g in the 1950s, and to 20.25 g in the 1960s. The amount dramatically increased from 1970 to 1980 (53.37 g) and kept rising until 2010 (71.26 g). The average consumption of red pepper in cabbage Kimchi in the 2010s is about 12 times that of the 1930s.