Most soybean cultivars have ovate leaflets, although a few cultivars have narrow or lanceolate leaflets. Narrow leaflet cultivars tend to have more seeds produced per pod than ovate leaflet cultivars, suggesting that the narrow leaflet trait is tightly linked to or cosegregating with the trait controlling number of seeds produced per pod (nspp). The objective of this study was to construct a high resolution map of a chromosomal region controlling narrow leaflet trait and nspp in soybean. A BC3F2 population from a cross between 'Sowonkong' and 'V94-5152' was used. Sowonkong have narrow leaflet and 4-seeded pod and V94-5152 have ovate leaflet and do not have 4-seeded pod. The plants of F2 populations showed a segregation ratio of 3:1 of ovate leaflet to narrow leaflet and then leaflet genotypes were obtained from F2:3 population of each F2 individual. The narrow leaflet-containing plants showed Sowonkong-like pod trait and the ovate leaflet-containing plants V94-5152-like pod trait. The results suggested that, in our mapping population, a single gene controls inheritance of the narrow leaflet character and the narrow leaflet trait is tightly linked to or co-segregating with the trait controlling nspp. Subsequently, we mapped the narrow leaflet locus near Sat_105, Satt270 and SM315 on soybean linkage group I that corresponds with the previously known ln locus. Work is ongoing to construct a fine molecular genetic linkage map on this MLG I region and to find a linkage relationship between ln and nspp. Our results should facilitate further elucidation for the relationship between ln/nspp and yield.

콩의 입중에 따른 이상초형(ideal type)의 개발을 위해 광합성호율이 높은 안전 다수성 콩 품종육성의 엽형 모델을 찾고자 엽형 및 입중에 따른 잎기능에 관련된 몇 가지 주요특성 및 CO2 이용효율과의 관계를 조사했는데, 그 결과를 요약하면 다음과 같다. 1. 대두 단엽의 CO2 동화량은 소립품종에서 장엽형 잎을 가진 품종이 19.66 umolm2s1로서 환엽형 잎을 가진 품종(18.29 umolm2s1)보다 높은 경향이었으며, 대립품종에서는 환엽형 잎을 가진 품종이 19.17 umolm2s1로서 장엽형품종(17.45 umolm2s1)보다 높았다. 2. 기공전도도가 0.12-0.13범위에서는 주로 대립, 장엽형 품종이 분포하고 있었으며 CO2 동화량은 17-18 umolm2s1정도로 낮았고, 0.14-0.15범위에서는 소립, 장엽형 품종들이 분포하였는데 CO2 동화량은 19-20 umolm2s1로서 높았다. 3. CO2 동화량에 영향을 미치는 전자생성량은 대립, 환엽형 잎을 가진 품종들이 0.82-0.83으로 가장 적었으나 CO2 동화량은 18-20 umolm2s1로서 높았다. 4. 주당 CO2 흡수량은 나물콩에서는 장엽형 품종이 68.5ppm으로 환엽형(46.5 ppm)보다 크게 높았으며 장류콩에서는 환엽형이 70.1 ppm으로서 장엽형(63.1 ppm) 보다 약간 높았다.