• Plant Breeding and Biotechnology
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• 제7권3호
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• pp.272-286
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• 2019

Developing elite hybrid rice varieties is one important objective of rice breeding programs. Several genes related to male sterilities, restores, and pollinators have been identified through map-based gene cloning within natural variations of rice. These identified genes are good targets for introducing genetic traits in molecular breeding. This study was conducted to breed elite hybrid lines with major genes related to hybrid traits and disease/insect resistance in 240 genetic resources and F₁ hybrid combinations of rice. Molecular markers were reset for three major hybrid genes (S5, Rf3, Rf4) and thirteen disease/insect resistant genes (rice bacterial blight resistance genes Xa3, Xa4, xa5, Xa7, xa13, Xa21; blast resistance genes Pita, Pib, Pi5, Pii; brown planthopper resistant genes Bph18(t) and tungro virus resistance gene tsv1). Genotypes were then analyzed using molecular marker-assisted selection (MAS). Biological assay was then performed at the Red River Delta region in Vietnam using eleven F₁ hybrid combinations and two control vatieties. Results showed that nine F₁ hybrid combinations were highly resistant to rice bacterial blight and blast. Finally, eight F₁ hybrid rice varieties with resistance to disease/insect were selected from eleven F₁ hybrid combinations. Their characteristics such as agricultural traits and yields were then investigated. These F₁ hybrid rice varieties developed with major genes related to hybrid traits and disease/insect resistant genes could be useful for hybrid breeding programs to achieve high yield with biotic and abiotic resistance.

• 한국작물학회지
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• 제40권5호
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• pp.608-618
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• 1995

본 연구는 잡종강세를 나타내는 두 조합의 벼 일대 잡종 품종, Shanyou 63, Teyou 53과 inbred계인 밀양 23호 등을 공시하여 벼의 잡종강세 발현기작을 규명코자 실시되었으며, 수행 후 얻어낸 결과를 요약하면 다음과 같다. 1. 종자 단백질 분석을 통해, 잡종강세 발현의 유전적인 특성들이 부분적으로 모본으로 부터 유전된다는 사실을 규명하였다. 2. Hybrid계 벼는 inbred계보다 배아의 크기가 크고 $\alpha$-amylase 활성 및 chlorophyll함량이 높게 나타났다. 이러한 특성들은 분얼능력, 특히 수량에 밀접한 영향을 끼치는 하부절간의 분얼수와도 관계가 있었으며, Shanyou 63의 경우 다른 inbred계에 비해 60~70%나 분얼력이 높았다. 3. 인위적으로 GA$_3$ 0.02 ppm을 처리한 후 $\alpha$-amylase활성 측정시, hybrid계에는 영향을 미치지 못하였으나 밀양 23은 무처리보다 높은 활성을 나타내었다. 이와 같은 결과는, hybrid계 벼의 종자내에는 이미 충분한 GA를 함유하고 있으며 이것이 초기활력과 관계있는 것으로 추정된다. 4. Cytochrome c oxidase의 활성은 inbred계 보다 hybrid rice에서 2.7~5.5배나 높게 나타났으며, 따라서 hybrid계 벼의 대사작용이 매우 높았다.

• Journal of Plant Biotechnology
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• 제43권3호
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• pp.317-331
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• 2016

Development of disease resistant plant is one of the important objectives in rice breeding programs because biotic stresses can adversely affect rice growth and yield losses. This study was conducted to identify lines with multiple-resistance genes to biotic stress among 173 hybrid rice breeding lines and germplasms using DNA-based markers. Our results showed that one hybrid rice line [IR98161-2-1-1-k1-3 (IR86409-3-1-1-1-1-1/IRBB66)] possessed 5 bacterial blight resistance genes (Xa4, xa5, Xa7, Xa13 and Xa21) while two hybrid rice lines [IR98161-2-1-1-k1-2 (IR86409-3-1-1-1-1-1/IRBB66) and 7292s (IR75589-31-27-8-33S(S1)/IR102758B)] possessed 3 bacterial blight resistance genes (Xa4, Xa7 and Xa21, and Xa3, Xa4 and xa5). Molecular survey on rice blast disease revealed that most of these lines had two different resistant genes. Only 11 lines possessed Pib, Pi-5, and Pi-ta. In addition, we further surveyed the distribution of insect resistant genes, such as Bph1, Bph18(t), and Wbph. Three hybrid breeding lines [IR98161-2-1-1-k1-3 (IR86409-3-1-1-1-1-1/IRBB66), IR98161-2-1-1-k1-2 (IR86409-3-1-1-1-1-1/IRBB66), and 7292s (IR75589-31-27-8-33S(S1) /IR102758B)] contained all three resistance genes. Finally, we obtained four hybrid rice breeding lines and germplasms [IR98161-2-1-1-k1-2 (IR86409-3-1-1-1-1-1/IRBB66), Damm-Noeub Khmau, 7290s, and 7292s (IR75589-31-27-8-33S(S1)/IR102758B)] possessing six-gene combination. They are expected to provide higher level of multiple resistance to biotic stress. This study is important for genotyping hybrid rice with resistance to diverse diseases and pests. Results obtained in this study suggest that identification of pyramided resistance genes is very important for screening hybrid rice breeding lines and germplasms accurately for disease and pest resistance. We will expand their cultivation safely through bioassays against diseases, pests, and disaster in its main export countries.

• 생명과학회지
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• 제7권4호
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• pp.347-354
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• 1997

Some attempts were made to investigate the gentic characteristics of the brown planthopper(BPH), Nilaparvata lugens Sta${\aa}$l, biotypes. In terms of egg and nymphal periods, egg hatcgability, emergence ratio, and population change of BPH and plant damage of rice cultivars by the infestation of BPH biotypes and their hybrid progenies in field conditions. The egg and nymphal periods of the three of BPH biotypes and their hybrid progenies on Dongjinbyeo with no resistance gene were shorter than on rice cultivars with resistance gene. But the periods of biotype-2(♀) X 2(♂) (E) on Samgangbyeo with Bph-1 gene and biotype-3(♀) X 3(♂)(I) on Mirying 63 with bph-2 gene were as short as on Dongjinbyeo. The egg hatchability and emergence ratio of the three Bph biotypes and their hybrid progenies on Dongjinbyeo were higher than on the other rice cultivars, and those of E on Samgangbyeo and I on Miryang 63 were as high as on Dongjinbyeo. In rice paddy field, biotype-1(♀) X 1(♂)(A)$\sim$I infested on Dongjinbyeo, E onSamgangbyeo, and I on Miryang 63 were increased their population densities remarkably in next generation. Dongjinbyeo infested by A$\sim$I, and Myryang 63 infested by I were hopperburned at 60 days after infestation and had a damage rating of 0.9. But Samgangbyeo infested by E was no hopperburn(damage rating: 7.3) though it showed high BPH population at 60 days after infestation.

• The Plant Pathology Journal
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• 제35권3호
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• pp.280-286
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• 2019

In this study, PVF11 was selected among 20 candidate pathogenesis-related genes in Burkholderia glumae based on its effect on virulence to rice. PVF11 was found to interact with several plant defense-related WRKY proteins as evidenced through yeast-two hybrid analysis (Y2H). Moreover, PVF11 showed interactions with abiotic and biotic stress response-related rice proteins, as shown by genome-wide Y2H screening employing PVF11 and a cDNA library from B. glumae-infected rice. To confirm the effect of PVF11 on B. glumae virulence, in planta assays were conducted at different stages of rice growth. As a result, a PVF11-defective mutant showed reduced virulence in rice seedlings and stems but not in rice panicles, indicating that PVF11 involvement in B. glumae virulence in rice is stage-dependent.

• 한국작물학회지
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• 제44권4호
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• pp.391-395
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• 1999

Barnyardgrass had relatively higher growth vigor at the earlier growth stage than inbred rice did, showing the 2 fold higher $\alpha$-amylase activity during the periods of germination and large leaf area Expansion with high net photosynthetic rate at the earlier autotrophic stage, but it performed weak growth at the late growth stage. However, the hlybrid rice Shanyou 63 had significantly higher $\alpha$-amylase activity and net photosynthetic rate than that of barnyardgrass, exhibiting heterosis for two physiologica1 traits during the germination (6~12 days) and autotrophic phase, respectively. Accordingly, hybrid rice, Shanyou 63, exhibited heterotic effect at the early growing stage when were presented with barnyardgrass. Shanyou 63 exhibited stronger tillering ability, faster leaf area expansion and higher net photosynthetic rate than those of barnyardgrass.

• 한국유기농업학회지
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• 제19권spc호
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• pp.144-147
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• 2011

The main nutritional problem of sorghum${\times}$sudangrass hybrid (Sorghum bicolor${\times}$Sorghum sudanese) silage is low quality and palatability. This experiment was conducted to evaluate whether organic com grain and crushed rice addition of sorghum${\times}$sudangrass hybrid silage increases forage quality of the silage. The sorghum${\times}$sudangrass hybrid silages with added com grain and crushed rice were similar to conventional com silage in moisture content. However organic sorghum${\times}$sudangrass hybrid silage had low pH values. Silage added with gain and byproduct had higher crude ash, acid detergent fiber (ADF) and neutral detergent fiber (NDF) contents than control com silages, while its non-fiber carbohydrate (NFC) and total digestible nutrients (TDN) showed the opposite results. Lactic acid, butyric acid and lactic percentage of total organic acid (L/T) of sorghum${\times}$sudangrass hybrid silages were higher than those of com silage, but acetic acid was higher than control. In vitro dry matter digestibility (IVDMD) of com silage was higher than other sorghum silages. Feed intake of sorghum${\times}$sudangrass hybrid silage added with crushed rice was highest among silages. Therefore, these data indicate that crushed rice and com grain added sorghum${\times}$sudangrass hybrid silage could be recommended as the most effective treatment for increasing silage quality and palatability.

• KSBB Journal
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• 제6권2호
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• pp.123-128
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• 1991

The production of bassinosteroid-like substances of two hybrid types of Korean rice, Jangseongbyeo, Taebackbyeo were investigated. The shoots at the maximum tillering stage were extracted and purified by solvent fractionation, silica gel adsorption chromatography Sephadex LH-20 chromatography, charcoal adsorption chromatography, Bondesil chromatography and HPLC of reverse phase, successively. Biological activities of each purification step were monitored by the rice lamina inclination test. Higher activities against the rice lamina inclination test in the each purification step showed that the shoots of two cultivars biosynthesize brassinosteroids. Two cultivars also showed a similar distribution of biological activities of endogenous brassinosteroids detected by HPLC.

• 한국식물학회:학술대회논문집
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• 한국식물학회 1999년도 제13회 식물생명공학심포지움 New Approaches to Understand Gene Function in Plants and Application to Plant Biotechnology
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• pp.21-35
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• 1999

We have previously isolated OsMADS4 gene that is a member of the class B MADS box genes from rice. In this study, another member of the class B MADS box genes was isolated from rice flower by the yeast two-hybrid screening method using OsMADS4 as bait. RNA blot analyses revealed that the clone, OsMADS16, was expressed in the second and third whorls, whereas the OsMADS4 transcripts were present in the second, third, and fourth whorls. These expression patterns of the OsMADS16 and OsMADS4 genes are very similar with those of AP3 and PI, the class B genes of Arabidopsis, respectively. In the yeast two-hybrid system, OsMADS4 interacted only with OsMADS16 among several rice MADS genes investigated, suggesting that OsMADS4 and OsMADS16 function as a heterodimer in specifying sepal and petal identities. We have also isolated OsMADS6 gene using OsMADS1 as a probe. Both are members of the AGL2 MADS family. Various MADS genes that encode for protein-protein interaction partners of the OsMADS6 protein were isolated by the yeast two-hybrid screening method. A majority of these genes belong to the AGL2 family. Sequence Homology, expression pattern, and ectopic expression phenotypes indicated that one of the interaction partners, OsMADS14, appears to be homologous to API, the class A MADS gene of Arabidopsis.

• 한국자원식물학회지
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• 제19권5호
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• pp.612-616
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• 2006

최근 GMO 작물의 재배, 생산이 날로 늘어나며 GMO 작물이 환경에 미칠 수 있는 많은 가능성들이 대두되고 있다. 특히 GMO 작물과 야생종과의 자연교잡에 의한 유전자 전이로, 잡초화의 문제점이 제기되며 생태계의 변화 및 파괴의 위험성이 우려되고 있다. 본 실험에서는 GM벼와 야생 및 근연종 사이의 교잡가능성 및 유전자 전이율을 조사하기 위한 유전자 이동의 분석 체계를 확립하고자 하였다. 벼의 개화시기에 GM벼와 야생 및 근연종 간의 인공교배 후 수확한 교잡 추정 종자를 발아시켜서 제초제를 처리하여 교잡종자를 선별하였다. 또한 GM 벼 및 야생 근연종벼들 간의 RAPD PCR 분석을 통해 선별한 marker를 사용하여 낙동 교잡벼와 샤레 교잡벼가 GM 벼와 교배된 식물체임을 확인하였다. PCR 분석을 수행한 결과 GM벼에서 도입된 trehalose-6-phosphate phosphatase (TPP) 유전자와 선별marker로 사용된 bar유전자가 GM벼 뿐만 아니라 샤레 교잡벼에도 존재하였으며, 결과적으로 GM벼의 bar 및 tpp 유전자가 잡초성벼인 샤레 교잡벼에 전이되었음을 검증할 수 있었다.