Studies on Agronomical Characteristics of Rice Varieties Recommended during 1910-1980 in Korea

수도 품종변천에 따른 유용형질의 특성변이에 관한 연구

Heading behaviour of native japonica (GI) and Japanese varieties (GII) grown during 1910-1920s were thermo-sensitive, home bred varieties during 1930s (GIII) - 1950s (GIV) were photo-sensitive and semi-dwarf indica derived varieties released since 1971 (GV) were controlled by basic vegetative phase. Number of leaves on main culm was increased with varietal improvement and culm length was gradually shortened as variety improved. GV variety had the shortest plant height among the groups. The first internode length was about 30cm in all groups and difference of 2nd-4th internode length was caused shortening the culm length. Panicle length and diameter of panicle neck were shortened and became thinner as variety developed from GI to GIV, however, GV had longer panicle and thick panicle neck, respectively. Number of panicles/hill and straw weight/hill increased and became heavier as variety improve from GI to GIV but GV had moderate number of panicle/hill and relatively light straw weight. Number of spikelet/panicle has been reduced with varietal improvement but GV had the biggest number. Grain yield/hill also increased as variety improved, however, it was decreased as transplanting season postponed and GV had shown the most sensitive difference. Top dry matter weight at heading stage and at 20 days after heading (20 DAH) had no difference among the groups except GI which was the smallest. Average grain weight at 20 DAH was heavier in the order of GI > GII, GV > GIV > GIII. It had a little variation in GI & GII while that of other variety group showed significant decrease as transplanting delayed. Harvest index (HI) of GV was the highest at 54% for the earlier transplanting and GIII had the lowest HI. Difference of HI became conspicuous for the later transplanting, the varieties bred later had the lower HI when transplanting of rice delayed. At the earliest transplanting applied (May 15), the grain yield was higher in the order of GI > GIV > GIII > GII > GI, however, that of Tongil type variety (GV) was the lowest for the latest transplanting (June 29). Interrelationship among the agronomical characteristics and grain yield was discussed.

우리나라 수도 품종의 시대적 변천에 따른 그들 품종의 생육형질 및 수량구성형질들의 변이를 조사비교하여 앞으로 품종육성 및 재배기술 발전에 필요한 기초자료를 얻고자 연대별 주요품종을 5개씩 25개 품종을 공시하여 5대 품종군, 즉 ${circled1}$1907년대의 재래품종들을 GI군, ${circled2}$ 1920년대의 도입품종들을 GII군 ${circled3}$ 1930년대에 육성 보급된 품종들을 GIII군, ${circled4}$ 1950년대에 육성 보급된 품종들을 GIV군, ${circled5}$ 1971년 통일품종 육성이후에 육성된 품종들을 GV군으로 구분하여 이앙시기를 5월 15일, 5월 30일, 6월 14일 및 6월 29일의 4회로 하여 시험조사 하였는데 그 결과는 다음과 같다.