초록 ▼

Ⅳ. 연구개발결과
제1세부연구과제에서는 유채 교배친 및 교배조합별 F₁, F₃ 및 F₄ 종자의 100립중을 비교분석해 종간교잡(탐미 x Sarsyun) F₄ 세대에서 지방산 대립종자(100립중 0.7g 이상) 12 계통을 선발하였다. 또한 1협4실 종자 ‘Sarsyun’(꼬투리 굵고, 종자수 평균 35개/협, 노란 종피)의 종자 발달단계별(개화 후 21, 28, 35, 42일) 전사체 분석 및 지방산생합성 유전자를 구명하고자, 발달중인‘Sarsyun

Ⅳ. 연구개발결과
제1세부연구과제에서는 유채 교배친 및 교배조합별 F₁, F₃ 및 F₄ 종자의 100립중을 비교분석해 종간교잡(탐미 x Sarsyun) F₄ 세대에서 지방산 대립종자(100립중 0.7g 이상) 12 계통을 선발하였다. 또한 1협4실 종자 ‘Sarsyun’(꼬투리 굵고, 종자수 평균 35개/협, 노란 종피)의 종자 발달단계별(개화 후 21, 28, 35, 42일) 전사체 분석 및 지방산생합성 유전자를 구명하고자, 발달중인‘Sarsyun’ 종자에 대해 종자 축적 대사물 관련 전사체의 발현패턴 및 발현량 변화를 조사하였다. 총 34,423 contigs에 대해 전사체 발현량 및 발현량 변화를 분석한결과, 지질 대사에 있어서는 oleosin과 지방산 합성 및 신장에 관여하는 대부분의 유전자는 각각 28 또는 35일에서 증가하였고, 종자 발달 후기단계에서도 높은 수준으로 발현되었음을 알 수 있었다.
제2세부연구과제에서는 종간교잡(B. napus, B. juncea, B. campestris, B. rapa, B. carinata,B. oleracea)을 통한 유전자 다양성 유기 및 F₁ 종자 획득하고, SCAR 마커(TCA1와 TTA 5)를 이용해 F₂ 세대에서 내한성 계통선발 및 마커 유전자 전이율을 조사하였다. F₁세대 중 SCAR 마커에 반응을 보인 10조합에 대해 F₂세대에도 동일한 마커를 이용하여 PCR분석한 결과, ‘한라’ × ‘TORI’(VI032711) 78.1%, ‘한라’ × ‘TORI’(VI032712) 43.8%, ‘한라’ בTORI’(VI032739) 34.4% 순서로 SCAR 마커 유전자 전이율이 높게 나타났고, 나머지 계통들은 전이율이 15% 미만으로 나타났다. 종간교잡 후대 계통에 대해서 내한성∙내건성 증진 정도를 구명하고자 최적 저온처리조건(처리온도 및 시간: -6℃에서 3일 처리, -8℃에서 1일 처리)을 탐색하였다. -8℃, 24시간 처리 시 CGMS, 겨울유채, 탐미, 탐라 유채 순으로 내한성이 강하게 나타났으나, 생존율과 전기전도도 측정 결과는 일치하지 않았다. 하지만 –6℃, 3일 저온처리조건은 비교적 내한성이 강한 계통들을 선발 할 수 있었고, 이러한 결과는 월동중 포장에서 내한성 검정시험 결과와 비교적 일치했다. 최종적으로 F₄ 세대(15교배조합)에서 내한성이 비교적 강한 유채 1,665 계통 확인하였다.
제3세부연구과제에서는 유채 화색변이 돌연변이체를 유기하기 위해 ‘탐미유채’ 등 10품종의 종자에 종자를 방사선(γ선, 1,000Gy) 처리한 후, M₃세대까지 세대전개를 실시하여, 각 세대에서 발생한 돌연변이체를 개체별로 자가수분하여 채종한 종자를 계통화하였고 세대를 전개하였다. 화색변이 15계통과 화형변이 5계통을 선발하였다. 또한 근연 종 및 속간 교잡을 통한 화색개량을 위해 종자친으로 영산유채(Brassica napus L.)등 3품종과 화분친으로 양배추(Brassica oleracea L.), 무(Raphanus sativus L.) 및 소래풀(Orychophragmus violaceus (L). O.E. Schuluz)을 이용하여 종속간 교배를 실시하여, 유채(B. napus) 탐미유채’ 와 양배추 (B.oleracea) ‘VI033139'의 종간교배의 F₁잡종 식물체에서 유채의 노란색과 양배추의 흰색의 중간인 미색 꽃 1계통을 선발하였으며, ‘한라유채’ × 소래풀(O. violaceus) ‘violet’의 속간 잡종식물체에서 모본인 유채보다 꽃의 크기가 매우 커진 1계통 선발하였다.

Abstract ▼

< 제1세부연구과제 : 바이오디젤용 고수율·대립 유채종자 개발 >
Seed size is an important component of yield in rapeseed (Brassica napus L.). In this study seed size (determined by 100-seed weight) in six rapeseed crosses between B. napus(maternal (♀) variety: Tammi, Tamla, Halla, Mokpo CGMS) and B. rapa (paternal (♂) vari

< 제1세부연구과제 : 바이오디젤용 고수율·대립 유채종자 개발 >
Seed size is an important component of yield in rapeseed (Brassica napus L.). In this study seed size (determined by 100-seed weight) in six rapeseed crosses between B. napus(maternal (♀) variety: Tammi, Tamla, Halla, Mokpo CGMS) and B. rapa (paternal (♂) variety: Sarso, Sarson, Sarsyun) were analyzed including parents and F₁ and F₃ generations. Differences in the mean 100-seed weight of F₁ and F₃ generations were detected in six crosses (Mokpo CGMS x Sarso, Mokpo CGMS x Sarson, Tammi x Sarsyun, Tammi x Sarson, Tamla x Sarsyun, Halla x Sarsyun). Mean 100-seed weight was highest in Tammi × Sarsyun cross. Several lines in F₃ generations of three cross combinations (Tammi × Sarsyun, Tamla × Sarsyun, and Halla × Sarsyun) showed about 0.7g of 100-seed weight. Fatty acid compositions in the three cross combinations were further analyzed. The large seed lines were accompanied by a simultaneous increase in erusic acid that derived from paternal parents. Based upon these results, large rapeseed seed lines with low-erusic acid would be selected in subsequent generations.
Tetralocular type of Brassica rapa has a wide silique, containing more seeds than in the bilocular type. We studied the physiological and molecular mechanisms underlying seed development of the tetralocular type by measuring total C, soluble sugars, and lipid content from 14 to 49 days after flowering (DAF) and changes in genome-wide transcript abundance during the seed filling. Hexoses (glucose and fructose) transiently accumulated in young seeds (14–21 DAF) at higher levels than sucrose, while high sucrose level was observed in mature seeds (21–49 DAF). Lipid accumulation in seeds began at approximately 21 DAF, reaching the maximum (45% dry matter) at 42 DAF. Lipid accumulation was likely correlated with gradual decrease in total soluble sugars in silique wall between 14 and 35 DAF. Most genes involved in seed photosynthesis and carbohydrate metabolism were highly expressed at 21 or 28 DAF and were subsequently downregulated. Expression of genes coding for oleosins and fatty acid synthesis and elongation markedly increased at 28 or 35 DAF, respectively, remaining high thereafter. Expression of major storage protein genes increased at 28 DAF and remained high from 35 to 42 DAF. Seed development was highly dependent upon photoassimilates of seeds and silique wall. The hexose-to-sucrose ratio in seed at 14-21 DAF was important for early embryo development. The sucrose-to-hexose ratio in seed at approximately 21 DAF appeared to induce the transition into the seed filling stage. Dynamic changes to transcript abundance of most genes in relation to seed storage products occurred at 28-35 DAF. Tetralocular ovary in B. rapa may be a useful trait for improving the seed yield and yield contributing traits in Brassica species.
< 제2세부연구과제 : 기후변화 대응 환경스트레스 내성 유채품종 개발 >
Rapeseed (Brassica napus) is a representative oil seed crop. It is on the second position in the edible oil sources behind to soybean and has brought much attention these days as an alternative biofuel source to replace fossil fuels. In recent, the unpredictable and rapid climatic change by global warming require more stable and sustainable production of rapeseed. In order to expand the cultivation area of rapeseed, development of rapeseed cultivate varieties with cold, drought, water logging and salt stresses tolerance is urgent. Among them, resistance to low temperature is most important factor during the winter season that affects plant growth, overwintering rates and seed yield of rapeseed. Thus, this research project was carried out to establish the critical low temperature treatment conditions and select low temperature resistant cultivars (or lines) using molecular markers for efficient breeding for the stable cultivation of rapeseed in the southern and central region of South Korea. To develope new rapeseed cultivars that are tolerant to coldness, we isolated a genomic DNA in F1 seedling derived from the crosses of various Brassica sup-cultivars (or cultivars) and the amplification with two sequence characterized amplified region (SCAR) marker primers(TCA1와 TTA 5) were tested. A detection of these specific fragments showed in F1-47, F1-49, F1-51, F1-53, F1-56, F1-57, F1-58, F1-59, F1-61,F1-62 cross seedlings. Also, the result of PCR reaction with same marker primers in the 10 F2 generation of them represent high transposition rates in the order as follows;‘Hanla’בTORI(VI032711)’78.1%, ‘Hanla’בTORI(VI03271 2)’ 43.8%, ‘Hanla’בTORI (VI032739)’34.4%, others (<15%). Finally, we tested cold tolerance trait for F4 hybrid generation. As a result, the phenotype of cold tolerance was observed in F4-17-3, F4-17-3, F4-17-3,F4-17-3, F4-17-3, F4-17-3, F4-58-5, F4-58-8, F4-58-16, F4-58-18, which are confirmed in the field test during winter season.
< 제3세부연구과제 : 경관용 유채 화색개량 연구 >
The cultivation area of Brassica napus has been increased in Korea for the large landscape complex. However, as the color of Brassica napus is very simple, diversification of color of Brassica napus is necessary to improve landscape effect. The seeds of ten rapeseed varieties were irradiated with 1,000 Gy of gamma rays and then cultured to M3 generation. 56 mutant lines were selected by estimating phynotype, ie dwarf(short stem), shape and color of flower. To make various colors of Brassica napus, interspecific and intergeneric cross was performed. As a result, while legume was formed through pollination, there were many siliques without seeds due to the failure of fertilization. In 10 days of cross, the embryo in the silique was degenerated and lost. As for the number of seed per silique was, Brassica napus × Brassica oleracea was 0.12, Brassica napus × Raphanus sativus was 0.40 and Brassica napus × Orychophragmus violaceus was 0.12. As for botanic characteristics of F₁ crossbreed hybrid, the style of leaf and color of flower were similar to those of Brassica napus and most had fertility. The interspecific cross of Brassica napus × Brassica oleracea generated ivory color of flower which is the medium color of parents, and intergeneric cross of Brassica napus × Orychophragmus violaceus created entities with larger flowers which seems to enhance landscape effect. As for backcrossing efficiency, the number of seed per legume of Brassica napus × Brassica oleracea was 0.61, Brassica napus × Raphanus sativus was 0.68 and Brassica napus × Orychophragmus violaceus was 0.48. The cross efficiency of Brassica napus and Raphanus sativus was the highest, and it had higher efficiency than F1 cross efficiency. 2 line of Interspecific and intergeneric hybrids were selected by size and color of flower. If backcrossing is performed continually, Brassica napus with other colors than yellow could be created that may enhance landscape effect.