초록 ▼

○ 연구결과
①갓의 세포질 웅성불임성은 배무채에서 가임개체가 많이 출현하여 이용할 수 없었으며 배추의 세포질응성불임성을 배무체에 현재 도입중임. ② 배추와 무의 복합내병성 계통을 이용한 신배무채 육성은 계통번호의 착오로 중도에 소실되였으며, ③고기능성 야생배추(좀배추)와 갯무간의 배무채는 기존 배무채와의 잡종획득과 그 잡종의 소포자 돌연변이유도 성공하여 기존 배무채와 형태가 전혀 다른, 그리고 유전적으로 안정된 신 계통이 현재 재검정중임. ④기존 배무채의 소포자 돌연변이유도로 유전적 안정성을 갖는 신 계통이 육성되어 세계 최초

○ 연구결과
①갓의 세포질 웅성불임성은 배무채에서 가임개체가 많이 출현하여 이용할 수 없었으며 배추의 세포질응성불임성을 배무체에 현재 도입중임. ② 배추와 무의 복합내병성 계통을 이용한 신배무채 육성은 계통번호의 착오로 중도에 소실되였으며, ③고기능성 야생배추(좀배추)와 갯무간의 배무채는 기존 배무채와의 잡종획득과 그 잡종의 소포자 돌연변이유도 성공하여 기존 배무채와 형태가 전혀 다른, 그리고 유전적으로 안정된 신 계통이 현재 재검정중임. ④기존 배무채의 소포자 돌연변이유도로 유전적 안정성을 갖는 신 계통이 육성되어 세계 최초로 "신종합성의 길을 열었다". ⑤맛좋고 고기능성의 신종식물 배무채 비비1호가 육성되어 현재 농가에 보급중이며, ⑥배무채의 소포자 배양기술이 확립되고, ⑦항암과 항균작용이 탁월한 썰포라펜이 배무채에 다량으로 함유되어 있음이 확인됨.

Abstract ▼

An inbred named Baemoochae had been reported to be bred as a new vegetable crop in xBrassicoraphanus, an inter-generic hybrid between heading Chinese cabbage, Brassica rapa ssp. pekinensis and big-rooted radish, Raphanus sativus. However it still required some improvement of the seed bearing ability

An inbred named Baemoochae had been reported to be bred as a new vegetable crop in xBrassicoraphanus, an inter-generic hybrid between heading Chinese cabbage, Brassica rapa ssp. pekinensis and big-rooted radish, Raphanus sativus. However it still required some improvement of the seed bearing ability and the uniformity which mean genetic stabilization as a plant, even though no problem was noticed in practical use. A cytoplasmic male sterile system and the diversification of the germplasm were also necessary for the F1 hybrid breeding to protect the variety right. This project composed of development of a cytoplasmic male sterility system, genetical stabilization of progenies and diversification of accessions with the mutation breeding, creation of new xBrassicoraphanus lines with hybridization between different materials in B. rapa and R. sativus, and the technical improvement of microspore culture for induced mutation.
To introduce the cytoplasmic male sterility to Baemoochae, a line, BB#6 were crossed to a CMS line of Brassica juncea which was known as Ogura CMS. More than 10 F₁ hybrid plants showed complete male sterility. However, about 15% of the plants in the first backcross generation(BC₁F₁) presented pollen and around 80% of the plants in the BC₂F₁ produced pollen. It was doubted If the fertility was induced by the restore gene of Ogura CMS originated from radish. However it was validated that it was not the Ogura system in a test with orf-138 gene which is responsible for it and its restore gene was not in Baemoochae in a test with molecular marker for it. Some semi male sterile plants which produce few pollen were observed at the BC₁F₁ and it was maintained with self pollination. When male sterile plants were crossed with semi sterile pollen, more than 70% of the progeny plants were male sterile and the others were semi sterile. This male sterile and semi sterile population(MSS line) multiplied with the semi male sterile line was used as female parent for F₁ seed production with Chinese cabbage as the male parent, since Baemoochae is highly fertile in this combination. The MSS line was multiplied with the semi-sterile line successfully and F₁ hybrid seeds between this MSS line and Chinese cabbage were produced effectively in the small size net houses with the honey bee pollinator and the F₁ hybrid was very uniform in the field test. However, unexpectedly seed yield of the F₁ hybrid was very low in a large scale open field and the uniformity of the F₁ hybrid was not good. The low seed yield was probably resulted from the malformed female sterile plants which were neglected in the small size population but about 26% in the field. The low uniformity was caused by the different pollen amount(content) of each semi male sterile plant in the MSS population. In the result, the CMS of B. juncea could not be used for xBrassicoraphanus and the reason what is the cause of the unstable male sterility is not yet clear. Now another Ogura CMS of B. rapa is employed to be introduced to Baemoochae.
Several dozens of the plants originated from microspore culture with/without the treatment of the mutagen, n-nitroso n-methyl urethane were acclimatized and self pollinated with the ordinary practice to the pollen production plants. Not many plants produced pollen and seeds obtained from them were also not many in the Mi1 generation regardless the mutagen treatment. One to 3 plants of the progeny lines were self pollinated again in the next generation(Mi2) to increase seeds for the field test. Remarkably, more than 6 seeds per pollinated flower were harvested from the best flower stalk of four lines out of 11 which were originated from the NMU treatment. It was quite distinguished ability compared to 3 seeds in the maximum pod in the wild line. This ability and the uniformity were tested on the open field with multiplied seeds at Mi2 generation. Every ovules of 9-11 in the pod were matured to the seed in the 4 mutant lines and only 1-3 seeds were progressed to the seed and the others were aborted during the maturing in the wild lines. The Amplified Fragment Length Polymorphism(AFLP) profile exhibited the same polymorphism rate as an F1 cultivar and a doubled haploid line in Chinese cabbage used for the standard. A mutant line was registered as BB#1 for variety protection and applied patent for domestic and Japan, China, EU, and USA. It is now released to farmers as a new vegetable crop. These genetic stabilization using induced mutation of inter-generic allopolyploid is probably the first achievement in the world and removed the barrier to prohibit synthesise the new species by the wide hybridization.
Some hybrids between different B. rapa and R. sativus accessions, which were resistant to multi-diseases, contented high disulfide chemicals or no hair on the leaf, were developed with the immatured ovule culture technique reported previously to diversify Baemoochae lines. Not many hybrids were established in every combinations and no self seeds were generally obtained from them, although they produced much pollen. Inevitably some plants were crossed with above mentioned mutant lines to keep their genetical properties. The hybrids were still very low in seed yield. Therefore they were donated to the induced mutation using the microspore culture as same as the earlier method. One of 37 plants derived from the induced mutation showed very high seed bearing ability in self pollination and in crosses with various Baemoochae lines. The progeny lines selfed or crossed were very uniform in morphology and very unique in appearance in the field test, even though their growing were not enough to observe every character because of the irregularly heavy rain fall during growing season this year, 2010.
Their genetic stability of the seed production and morphological characters is now confirming again. If it is proved, it would be a broadcasting announcement that the induced mutation using microspore culture is a new technique for genetic stabilization of the allopolyploids in Brassicaceae.
It has been reported previously that the Baemoochae plant produces a few embryo in the microspore culture. However the embryo yield was so low as less than 8 per Petri-dish and so fluctuated culture to culture that induced mutation using microspore culture couldn't be applied. The line code BB#12 which is stabilized genetically by the induced mutation was selected as the high embryo yield accession from the genotypic specificity trial. Its embryo yield was 18 in the mean and 56 in the maximum per Petri-dish. Single and co-treatment of gum arabic with Larcoll was effective in embryo development. A medium named B5M2-II which was modified the B5 medium by reducing nitrogen content and increasing calcium and potassium was devised for enhancing the number of normal plants which could be transplanted directly to the acclimation bed from the transplanted embryos. This result implies that induced mutation using microspore culture could be applied effectively in xBrassicaoraphanus.