양질대두 품종 육성을 위한 고함황 단백질 및 lipoxygenase 저활성도 품종의 탐색과 그의 유전 및 선발효과 2. Lipoxygenase 저활성도 품종의 탐색과 그 유전 및 선발효과 연구

Studies on Search for Varieties of Higher Sulfur Containing Protein with Lower Lipoxygenase Activity and Their Inheritance and Selection Efficiency for Breeding of Good Quality Soybean Cultivar 2. Variation of Lipoxygenase Activity and its Inheritance with Selection Efficiency

콩의 lipoxygenase 활성이 낮은 품종의 육성을 위한 유전육종학적 기초연구의 일환으로 서울대학교 농학과에서 유지해오고 있는 품종 및 계통과 국내 수집계통 등 507점을 공시재료로 하여 lipoxygenase 활성의 변이, 그리고 잡종초기세대를 통한 lipoxygenase 활성의 유전 및 선발효과를 조사한 결과는 다음과 같다. 공시품종 및 계통들의 lipoxygenase 활성은 50~670 unit (unit : $\Delta$0.001/min /mg, 234nm) 의 범위(507품종 및 계통)였으며 평균 350unit로 나타났다. 수집지역과 종실색 구분에 의한 각 그룹별 lipoxygenase 활성의 평균간 차이가 없었으며 성열이 이른 계통의 집단이 lipoxygenase 활성평균이 낮았다. Lipoxygenase 활성은 양적인 유전현상을 나타냈으며 활성을 높게하는 유전자의 상가적 효과가 우성효과보다 큰 것으로 나타났고 활성을 높게하는 유전자와 낮게하는 유전자의 분포비율은 비슷한 것으로 추정되었다. 추정된 협의의 유전력과 광의의 유전력은 0.78($H_n$), 0.86($H_b$)이었고, 선발효율은 고, 저 양 방향으로의 조기세대 선발에 의해 원집단에 비해 높은 방향의 선발에서 29.7~44.7%증가하였고 낮은 방향의 선발에서 21.8~27.3% 저하되었으며 모든 경우에 유의하게 선발효과가 있었다.

Lipoxygenase activity of soybean seeds of approximately 507 genotypes as well as its inheritance and selection efficiency in early breeding generation was measured in the Department of Agronomy, Seoul National University to facilitate breeding for low lipoxygenase activity of soybean. Average seed lipoxygenase activity of 507 cultivars and strains was 350 unit (unit: $\Delta$0.01 /min. /mg at 234nm) and ranged from 50 to 670 unit. There was no difference in mean lipoxygenase activity according to apparent seed characters such as seed coat and embryo color. But early mature soybean genotypes had fairly low lipoxygenase activity. Lipoxygenase activity was inherited quantitatively, in which additive effect was greater than dominant one and proportion of gene with positive effects was similar to that with negative ones. Estimated narrow- and broad-sense heritabilities were 0.78 and 0.86 for lipoxygenase activity, respectively. Heritability measured from selection in early breeding lines for high or low lipoxygenase activity was 64~76% or 54~62%, respectively. And selection for high lipoxygenase activity increased by 29.7~44.7%, whereas that for low ones decreased by 21.8~27.3%, respectively, when compared to random population. Clear effect in selecting of lipoxygenase activity was present in early generation.