Abstract
This study was conducted to see the feasibility of breeding for sprout soybean cultivar with minimum benny flavor using lipoxygenase-less lines. Lipoxygenase-less cultivar Jinpumkong2 was crossed by lipoxygenase containing Gwangankong, Sebaeknamulkong, and Pureunkong as paternal parent and 24 lipoxygenase-less lines derived from those 3 combinations were selected and those lines were evaluated with their parental cultivars. Germination rate showed no difference between lipoxygenase-less lines and their parental cultivars, however, rates of normal sprout of those and Jinpumkong2 were 63 and $56\%$, and were lower than that of paternal parents. Hypocotyl length of those was same as Jinpumkong2, however, shorter than paternal parents. Texture characteristics including hardness, cutting force and mastication of 96 hour-cultured sprout of lipoxygenase-less lines showed higher value than that of their parental cultivars. Lipoxtgenase isozyme was not detected in the sprout cotyledon of lipoxygenase-less lines, however it was observed in the sprout hypocotyl of all the used genotypes. Though lipoxygenase activity in the seed of lipoxygenase-less lines was lower than that of Jinpumkong2(0.477, ${Delta}A$ 234 nm min-1 mg meal-1),2 lines revealed more than 0.5 value. Lipoxygenase-activity of 2 day-cultured sprout(both cotyledon and hypocotyl) was the highest, decreased in 3 days after culture and re-increased thereafter. Several lipoxygenase-less lines with lower lipoxygenase activity of sprout than Jinpumkong2 were selected and this suggested the possibility of breeding lines for soy-sprout with low benny flavor.
본 연구는 lipoxygenase 결여 품종인 진품콩2호와 lipoxygenase 가 존재하는 광안콩, 소백나물콩, 푸른콩의 교배조합 내의 각 계통의 lipoxygenase 유무를 확인하고 activity 차이를 규명함으로써 lipoxygenase 결여 나물콩 육성의 가능성을 알아보고자 수행되었다. 콩나물 재배일수별 lipoxygenase 여부, 재배일수별 lipoxygenase 활성도 등을 분석한 결과를 요약하면 다음과 같다. 1. 콩나물 발아율은 대비품종과 계통들간의 큰 차이는 없었지만 정상 발아 개체율 에서는 계통이 $63\%$로 낮았으며 $T_{50}$은 1일로 소백나물콩, 푸른콩(0.6일)보다는 느렸으나 진품콩2호, 광안콩보다는 빨랐다. 2. 콩나물 생육은 치상 후 2일부터 콩나물 전체길이, 배축길이, 배축 직경을 조사한 결과 진품콩2호와 푸른콩 교배 조합 계통의 4537계통(콩나물 전체길이 13.9cm, 배축 길이: 7.3cm, 배축 직경: 2.2mm)이 대비품종들보다 높은 신장성을 보였다. 3. 콩나물의 물성은 치상 후 96시간 후에 hardness, cutting force, masticcation을 측정한 결과 lipoxygenase 결여 계통이 대비품종들보다 높게 측정되었다. 4. 콩나물 재배 일수 별 lipoxygenase band는 자엽부에서는 종실과 같이 lipoxygenase band를 확인 할 수 없었으며 배축부에서 모든 계통과 대비품종에서 확인 할 수 있었다. 5. 콩나물 재배 일수별 lipoxygenase 활성도는 2일차에 최고로 높았으며, 3일차에 최저치로 낮아진 후 다시 증가하는 양상을 나타내었다. 6. 각 교배 조합 내에서는 진품콩2호보다 활성도가 낮은 4510, 4522, 4537계통들이 lipoxygenase 결여 콩나물로서의 육종 가능성이 높을 것으로 생각되었다.
