‘백옥찰’은 내도복성이며 복합내병충성을 갖춘 중만생종 찰벼 품종을 육성하고자 국립식량원 기능성작물부에서 육성된 새로운 찰벼품종이다. ‘백옥찰’의 출수기는 중부평야지 및영․호남평야지 보통기 보비재배에서 8월 20일로 ‘신선찰벼보다 9일 늦은 중만생종이며, 이모작에서는 ‘남평벼’ 보다 1일 늦고, 만식에서는 ‘남평벼’ 보다 3일 늦은 중만생종이다‘백옥찰’의 줄기 두께는 ‘신선찰벼’와 같이 중간 정도이나 강도는 ‘신선찰벼’보다 강한 편이고 분얼개도는 보통이며, 탈립은 ‘신선찰벼’에 비해 잘 되는 편이다. 주당수수는 ‘신선찰벼보다 3개가 적으나 수당립수는 20여개가 많고 등숙비율은 ‘신선찰벼’에 비해 9% 높으며 현미 천립중 또한 ‘신선찰벼에 비해 무거운 편이다. 도정특성은 ‘신선찰벼’보다 다소 높으며, 특히 백미 완전립율이 ‘신선찰벼’에 비해 월등히 높은 편이다. 현미 장폭비는 1.71로 ‘신선찰벼’에 비해 쌀알이 약간 작은 편이며 단백질 함량 및 알카리 붕괴도 등 이화학적 특성은 ‘신선찰벼’와 같은 편이다. 불시출수가 없었으며, 성숙기의 엽노화가 중간 정도를 보였다. 내냉성 검정 결과 ‘신선찰벼’보다 출수지연은 적었고 및 냉수구 임실율은 약간 높았으며 수발아는 잘 안되는 편이었다. 도복관련형질에 있어서 벼키는 ‘신선찰벼’와 같으나 중심고, 좌절중, 모멘트 및 도복지수 등 도복관련 형질에서는 전반적으로 ‘신선찰벼’보다 큰 편이었고 포장 도복은 없었다. 잎도열병 밭못자리 검정결과 ‘백옥찰’은 전국 평균 도열병 저항성 정도가 ‘신선찰벼’와 비슷한 저항성을 보였으며, 목도열병의 경우 현지 포장검정에서는 발병되지 않았고 내구저항성은 강하였다. 흰잎마름병(K1-3), 줄무늬잎마름병에는 저항성이고 오갈병 및 검은줄오갈병에는 감수성이었다. ‘백옥찰’의 수량성은 중부평야, 호남․ 충남평야 및 영남평야지 보통기 보비재배 6개소에서 쌀 수량은 526 kg/10a으로 대조품종보다 9% 증수된 높은 수량성을 보였다. ‘백옥찰’은 중부 및 영호남내륙평야 1모작지대에 적응성이 높은 중만생종이다.

The use of functional markers, it is expected to make direct identification about genetic diversity at DNA level and overcome the problem of recombination /linkage. These markers can be used to identify interesting alleles in a breeding program and indirectly select for the trait, saving money, time and labor. Bacterial blight of rice caused by Xanthomonas oryzaepv. Oryzae is a destructive disease in rice production worldwide. No bactericide is effective to control the bacterial blight disease yet. Xa3, which is a gene conferring resistance to BB of the rice plant has been previously characterized by map-based cloning. We have cloned and sequenced the Xa3/xa3 gene in Korean cultivar, Hwayoung, Ilmi and Goun with gene specific primers. Our work detected polymorphisms and PCR-based allele specific SNP markers were developed. Susceptible or resistant individuals from an F2 population developed from across between Milyang244 and Ilmi, Korean germplasms and near isogenic lines carrying BB resistance genes were screened with allele specific markers. We found that the genotype completely matched their phenotype to BB using ASP-primers. These markers could be effective to marker-assisted selection for the Xa3 gene in rice breeding programs.

The green rice leafhopper (GRH), Nephotettix cincticeps Uhler, is one of the most serious insect pests affecting cultivated rice (Oryza sativa L.) in temperate regions of East Asia. To understand the genetic basis of the GRH resistance, a F2 population derived from across between a highly resistant variety,Cheongnam and a susceptible variety, Junambyeo was analyzed by genetic analysis and association mapping. GRH resistance was evaluated using the F2 populations. The results showed that a single dominant gene in Cheongnam. DNA from 22 F2 individuals being either resistant or susceptible were pooled to produce bulk resistant and bulk susceptible DNA samples. Parents and bulks were screened with 192 SSR markers and twolinked SSRmarker, RM6082 and RM20145 were identified.Subsequent mapping in the original mapping population showed that thelocusis flanked by the SSR markers, RM20130 and RM20152 on chromosome 6. To physically map this locus, the-linked markers were landed on the artificial chromosome clones of the reference cv., Nipponbare, released by the International Rice Genome Sequencing Project. The DNA markers found to be closely linked to Grh3 would be useful for marker-assisted selection for the improvement of resistance to GRH in rice.

Rice stripe disease, caused by rice stripe virus (RSV), is one of the major virus diseases in east Asia. The objective of this study was conducted to identify new resistance genetic source to rice stripe virus (RSV) disease. Genetic diversity of 155 rice cultivars was evaluated using 9 co-dominant InDel markers and STS marker ST10. These cultivars were classified into two groups by cluster analysis based on Nei`s genetic distances. The marker showed different band pattern among RSV resistance or susceptible cultivar. In comparison with bioassay for RSV resistance and genotyping using SSR markers showed that Stv-bi and InDel 7 marker observed recombination value within 3.8% and RSV resistance gene was closely related to InDel 7. Also InDel 7 divided as resistance type alleles and susceptible type alleles except for some varieties. Interestingly, 02428, Daw dam, Erguailai, Padi Adongdumarat, PERVOMAJSZKIJ, and Tung Ting Wan Hien 1 showed Japonica type in InDel 7 marker. However, these cultivars revealed resistant to RSV bioassay. These results indicate that those cultivar can be able to get the different gene resistance with Stv-bi gene. Newly identified resistance gene is considered useful for improving RSV resistance in japonica rice. Therefore, we will progress the allelism test and genetic analysis for identification of new gene source.

Amylose content of rice endosperm is one of the determinants of rice eating quality. This study was conducted to elucidate the mode of inheritance of dull gene in Milyang262, tentatively designated as du7(t), and to identify the molecular marker for du7(t) to be employed in marker-assisted breeding and gene pyramiding. Genetic analysis was carried out on F2 population derived from a cross between Junam and Milyang262. The low amylose content of Milyang262 was indicated to be under single recessive control. Allelism tests were as well conducted by crossing Milyang262 with Baegjinju and Baegokchal, which harbor du1 and wx gene, respectively. du7(t) was demonstrated to be inherited independently to du1 and wx. F2 population of Baegokchal/Milyang262 was used for molecular mapping. Linkage analysis was conducted on a population consisted of 120 individuals by several SSR markers. Initial mapping indicated that du7(t) is located on the end of long arm of chromosome 6 between SSR marker RM20590 and RM3509. To fine map the gene, a bigger population and several additional markers were employed. du7(t) was further mapped to a 1.74 Mb region between two SSR markers (RM6926 and RM412). Furthermore, we indentified three SSR markers that co-segregated with du(t) i.e. RM6811, RM3765, and RM176.

2000년대 후반 국내 쌀 소비량의 지속적인 감소와 MMA물량으로 인한 국내 양곡 재고부담이 가중되면서 쌀가공품에대한 관심과 함께 원료곡의 원가절감 대안으로 초다수성 품종이 재조명을 받게 되었다. 따라서 가공용으로 사용되는 원료곡의 가격경쟁력을 높이기 위해서 복합내병성이며 수량성이 높은 ‘한아름2’를 육성 하였다. ‘한아름2’의 출수기는 평야지 보통기 다비재배에서 8월 14일로 중생종이며, 간장은 76㎝로 ‘다산벼’보다 약간 크고 수당립수는 ‘다산벼’보다 약간적은 편이나 등숙률이 85.7%로 높고 현미천립중은 23.0g으로 비슷하다. ‘한아름2’의 불시출수와 수발아 및 포장도복은없었으며, 내냉성은 약한 편이다. 잎도열병, 목도열병, 줄무늬잎마름병, 오갈병 및 흰잎마름병(K1, K2, K3, K3a)에 강하고,검은줄오갈병에는 중정도의 저항성을 보였고 벼멸구에는 감수성이다. 쌀알은 맑고 심백이 약간 있으며 단백질함량은 8.2%로 ‘다산벼’보다 높았으나 아밀로스함량은 17.5%로 ‘다산벼’보다 낮았다. ‘한아름2’의 쌀수량성은 2008년부터 2010년까지 3년간 실시한 지역적응시험 결과 보통기 다비재배(6개소)에서 7.58MT/ha로 ‘다산벼’대비 13% 증수되었다. ‘한아름2’는 중부 및 영호남 평야지가 적응지역이다.

‘동보’는 국립식량과학원 영덕출장소에서 1996년 하계에 밥맛이 뛰어나면서 재배 안정성이 높은 벼 품종을 육성할 목적으로 내풍성이면서 각종 병해에 강한 영덕19호를 모본으로밥맛이 우수한 ‘고시히카리’를 부본으로 인공교배를 실시하고, 1996/1997 동계에 24개체의 F1 식물체를 양성하여 YR18320의 교배번호를 부여하였다. 1997년 하계포장에 F2 집단 전개 후 선발하여 1998년 하계에 F3세대 51계통을 육성하고, 이후 F4～F8세대를 계통육종법으로 전개하여 내도복성이면서 풍해에 강하고 병해에 안정적인 저항성을 나타내는 계통을 선발하여 2006년 생산력검정예비시험, 2007년 생산력검정본시험을 실시한 후 완전미율이 높고 식미가 우수하면서재배 안정성이 높은 YR18320-21-1-1-2-2-2을 선발하여 ‘영덕49호’로 명명하였다. 2008년부터 2010년까지 3년간 지역적응시험을 실시한 결과 중생종이면서 쌀 품위가 좋고 밥맛이 양호하며 내풍성과 내병성에 양호한 것으로 평가되어2010년 12월 농작물 직무육성 신품종 선정위원회에서 국가품종목록으로 등재 할 것을 결정하고 ‘동보’로 명명하여 적응지역인 동남부해안지, 중부평야 및 남부중산간지에 보급하게되었다. ‘동보’의 출수기는 보통기 재배에서 평균 8월 13일로‘화성벼’보다 1일 늦은 중생종 품종이다. 직립 초형이고 탈립은 잘되지 않고 이삭추출은 양호 하고 까락이 거의 없다. 수당립수는 ‘화성벼’보다 약간 많은 편이고 현미천립중은 23.6g으로 ‘화성벼’보다 더 무겁다. 도정특성과 완전미률은 ‘화성벼’보다 약간 좋은 편이고 외관특성이 맑고 투명하며 밥맛은‘화성벼’보다 우수하다. 불시출수는 안되는 편이나 수발아는‘화성벼’보다 더 잘되고, 위조현상에 강하고 성숙기 엽노화가느린 편이며 내냉성은 ‘화성벼’와 같은 수준이다. 잎도열병밭못자리 검정 결과 중도저항성을 보였고 줄무늬잎마름병과흰잎마름병(K1, K2, K3)에는 강하나 오갈병 및 검은줄오갈병에 약하고 벼멸구 등 충해에는 감수성이다. ‘동보’의 수량성은 ’08～’10년 3개년간 실시한 지역적응시험 보통기 보비재배 4개소에서 5.71 MT/ha로 ‘화성벼’ 대비 3% 증수되었으며, 이모작재배에서는 4.79 MT/ha ‘남평벼’ 대비 4% 감수되었고, 만식재배에서는 4.75 MT/ha로 ‘남평벼’와 같았다. ‘동보’의 적응지역은 동해안냉조풍지, 중부평야지 및 남부중산간지이다.

‘영호진미’는 쌀의 외관과 밥맛이 양호한 고품질 벼를 육성하고자 ‘03/'04 동계에 밥맛이 우수한 양질미 히또메보레와단간이면서 내병성이 양호한 주남벼를 부본으로 인공교배하여 육성하였다. 그후에는 조기에 고정된 계통을 얻고자 약배양을 실시하였으며, YR24733Acp10 계통을 선발하여 밀양228호의 계통명을 부여하였다. 07~’09년 3개년간 지역적응시험결과 우수성이 인정되어 농작물 직무육성 신품종 선정위원회에서 국가목록 등재 품종으로 선정되었다. ‘영호진미’는 영남평야 1모작지에 적응성이 높은 중만생 고품질 벼 품종이다.‘영호진미’의 출수기는 남부평야지와 남부 및 서남부해안지보통기재배에서 8월 21일로 ‘남평벼’보다 5일 늦은 중만생종품종이다. 간장과 수당립수는 ‘남평벼’보다 적은 편이고 현미천립중은 ‘남평벼’보다 약간 무거운 편이다. 도정특성은 ‘남평벼’와 비슷한 편이고 단백질함량은 ‘남평벼’보다 낮고 밥맛은 양호한 편이다. 불시출수는 없으며, 수발아는 ‘남평벼’와비슷하였으며, 내냉성은 중정도이고 냉수구 출수지연일수가긴 편이다. 잎도열병 밭못자리 검정 결과 약한 반응을 보였고,흰잎마름병에는 레이스 K1, K2, K3에는 저항성이지만 K3a에는 이병성이다. 줄무늬잎마름병에는 저항성이지만 오갈병과검은줄오갈병에는 약하고 벼멸구 등 해충에도 약하다. ‘영호진미’는 영호남 평야지 1모작 적응 품종으로, 수량성은 2007년부터 2009년까지 3년간 실시한 지역적응시험 결과 남부 및남서 해안지와 호남평야지, 영남평야지의 보통기 보비재배 10개소에서 5.44 MT/ha로 ‘남평벼’보다 3% 감수되었다.

국내 주요 해충인 끝동매미충에 대한 저항성 품종‘청남’은 ‘기누히까리’와 ‘밀양189호’를 각각 모본과 부본으로 인공교배 한 후 약배양으로 육성하였으며, 주요 연구결과는 아래와 같다. 출수기는 평야지 보통기 재배에서 8월 11일로 중생종이며 수당립수는 ‘남평벼’보다 적은 편이고 현미천립중은 무거운 편이다. 불시출수는 발생하지 않았으며, 수발아는 ‘남평벼’보다 약간 높은 편이고, 포장도복은 없었으며, 내냉성은 ‘남평벼’와 비슷하다. 잎도열병 밭못자리 검정 중 정도 저항성을 보였으며, 줄무늬잎마름병과 흰잎마름병(K1, K2, K3)에는 강하며, 바이러스병을 매개하는 끝동매미충에 저항성으로 오갈병에 포장저항성을 나타낸다. 검은줄오갈병에 약하고 벼멸구 등 충해에는 감수성이다. ‘청남’의 끝동매미충 유전분석을 수행한 결과 1개의 단순우성유전자에 의해 지배됨을 확인하였다. ‘청남’의 쌀은 맑고 투명하며 완전미율이 높았으며, 밥맛은 양호한 편이다. ‘청남’의 수량성은 2007년부터 2009년까지 3년간 실시한 지역적응시험 보통기 보비재배 11개소에서 5.43 MT/ha, 이모작재배에서는 5.00 MT/ha, 만식재배에서는 5.18 MT/ha이었다.

고령화 사회로 접어들면서 만성 신부전증 환자는 증가되고 있으며, 저단백질 식품에 대한 수요도 증가되고 있다. 중국173/주남벼 재조합 집단을 이용하여 저Glutelin 고품질 벼 품종개발의 육종효율 증진을 위해 DNA마커의 이용성을 검토하였으며, 밥맛향상을 위해 미질관련 형질들과 상관분석을 수행하였다. 중국173호/주남벼 재조합 집단에서 SDS PAGE결과 얻어진 저Glutelin 표현형과 functional DNA marker의 유전자형이 일치하여 DNA marker를 이용한 선발이 가능함을 확인하였다. 밥맛향상을 위해 미질관련 형질들과 상관분석을 수행한 결과, 윤기값과 Amylose 함량은 유의한 부의 상관을 나타내었으며, 단백질 함량은 윤기값에 많은 영향을 미치지 않았다. 반면, 단백질 조성에 따른 저Glutelin 계통군과 정상계통군의 비교에서 저Glutelin 계통군은 정상군에 비해 유의하게 윤기값이 낮았으며, 저Glutelin-저Amylose 계통군과 정상계통군은 대등한 윤기값을 유지하였다. 따라서 고품질 저Glutelin 품종개발을 위해 저Amylose 유전자의 활용이 바람직한 것으로 판단되었다. 이들 분석결과와 주요 농업적 특성을 고려하여 저Glutelin-저Amylose인 유망계통 밀양262호를 육성하였으며, 금후 고품질 저Glutelin 품종개발에 활용될 것으로 기대된다.

Rice is a staple food for more than 50% of the world's population. Embryo comprises only 2 to 3% of the weight distribution of the entire pericarp but has higher concentration of vitamins, proteins, and essential fatty acids than the other parts of grains. Moreover, α-tocoperol, γ-oryzanol, phytic acid and γ-aminobutric acid that have nutraceutical value are abundant. Increasing the volume of embryo assures the fortification of nutritional value of rice grain. We developed new black waxy giant embryo rice, Milyang 263 by crossing Josaengheugchal, a black waxy rice variety, and get, a giant embryo mutant generated by tissue culture. The nutrient contents and physical properties of Milyang 263 were compared with several giant embryo mutants and normal embryo rice varieties. Changes in the nutrient properties after germination were also observed. Results indicated that this new black waxy giant embryo rice, Milyang 263, offers a promising source for improving nutritional quality of rice especially anthocyanin, essential minerals, and GABA.

‘만미벼’는 작물과학원 영남농업연구소(현 국립식량과학원 기능성작물부)에서 2002년도에 육성한 중만생 저아밀로스 반찹쌀 품종으로 주요특성과 수량성을 요약하면 다음과 같다. 1. 출수기는 남부평야지의 보통기재배에서 8월 16일로 ‘동진벼’ 보다 2일 빠른 중만생종이다. 2. 수당립수는 ‘동진벼’ 보다 18개 많으나, 현미천립중은 19.9 g으로 ‘동진벼’ 보다 가벼운 편이며 등숙비율이 약간 떨어진다. 3. 위조현상에 강하고 성숙기 엽노화가 느린 편이며 내

Experiments were conducted to investigated the change of primary dormancy and viability of Chinese milk vetch(CMV) seed buried in soil both as seed and pod with seeds under CMV-rice cropping system during the period of 2007～2009. The freshly harvested CMV seed alone and pods with seeds were buried in rice field at 0, 5 and 10cm depths and determined change of seed dormancy and viability at one to three month intervals for 10 months. The CMV seed had high dormancy of 95%, showing only 4～5% germination at the beginning in June but the seed dormancy was gradually broken at rice harvest time in autumn, showing 25 to 35% for seed and 55 to 61% for pod with seeds. The viability loss was faster in the seed than in the pod with seeds regardless of depths of placement in the soil base on decayed seeds. Also the seed placed on the soil surface lost viability faster than the 5～10 burial depths. However, appreciable number of CMV seeds still remained at even 4 months after burial in soil. These results indicate that seed dormancy was enable CMV plant to regenerate naturally from the remained soil seed bank at rice harvest time in autumn.

Field experiments were conducted to investigate persistence of Chinese milk vetch(CMV) seed under naturally reseeded CMV-rice cropping systems during the period of 2007～2009. Persistence of the CMV seeds were evaluated in the naturally reseeded CMV-rice field on different tillage methods and soil depths based on the seed number recovered and the seed longevity in soil. Field observation in the naturally reseeded CMV rice field showed that as many as 917～2,185 CMV seeds m-2 were found from 0～15cm soil depth in the rotary tillage and 250～10,105 CMV seeds in minimum tillage rice cultivation in autumn. The recovered seed germinated 25～33%, 23～43% but still had high percentage of hard seed having 64～72% and 51～77%. Field experiment showed that the CMV seedling still emerged even after 2 years of continuous destructive killing of emerged CMV plant by rotary tillage in naturally reseeded CMV-rice field, indicating that CMV seeds persistent at least two years in rice field.

Rice blast resistance is considered one of the most important traits in rice breeding and the disease, caused by Magnaporthe grisea Barr, has brought significant crop losses annually. Moreover, breakdown of resistance normally occurs in two to five years after cultivar release, thus a more durable resistance is needed for better control of this disease. We developed a new variety, Keumo3, which showed strong resistance to leaf blast. It was tested in 2003 to 2007 at fourteen blast nursery sites covering entire rice-growing regions of South Korea. It showed resistance reactions in 12 regions and moderate in 2 regions without showing susceptible reactions. Durability test by sequential planting method indicated that this variety had better resistance. Results showed that Keumo3 was incompatible against 19 blast isolates with the exception of KI101 by artificial inoculation. To understand the genetic control of blast resistance in rice cultivar Keumo3 and facilitate its utilization, recombinant inbred lines (RIL) consisting of 290 F5 lines derived from Akidagomachi/Keumo3 were analyzed and genotyped with Pizt InDel marker zt56591. The recombination value between the marker allele of zt56591 and bioassay data of blast nursery test was 1.1%. These results indicated that MAS can be applied in selecting breeding populations for blast resistance using zt56591 as DNA marker.

Brown planthopper (BPH) is a major insect pest of tropical indica and temperate japonica rice in Asia and Africa. A major BPH resistance gene, Bph18 derived from IR65482-7-216-1-2 has been fine mapped on chromosome 12 and confers strong resistance to the Korean biotype of BPH. The Bph18 gene is tightly linked to the STS marker, 7312.T4A and is non-allelic to previously reported resistance genes present on chromosome 12. The Bph18 gene has been transferred into two elite japonica cultivars (Jinbubyeo and Junambyeo) background through marker-assisted backcross breeding (MAB) strategy. Foreground selection using STS markrs linked to the Bph18 gene in advanced backcross progenies confirmed homozygous marker alleles associated with BPH resistance. Background selection of the breeding lines with 260 simple repeat (SSR) markers revealed rapid conversion toward recurrent parent genotypes with less donor chromosomal segments (5.3-16.7%). Major agronomic traits of the progenies were analyzed and some breeding lines have agronomic traits comparable to the recurrent parent. One breeding line (S.523) with multiple-resistance to BPH and major diseases, desirable agronomic traits and grain quality has been recommended for regional testing in Korea. MAB is the suitable strategy to incorporate new genes into susceptible japonica to develop elite breeding lines.

Many important traits have been tagged allowing plant breeders to apply marker assisted selection (MAS) in rice. PCR itself is simple to set up, and requires little hands-on time. However, a crucial limiting step of MAS programs is the reliable and efficient extraction of DNA which can be performed on thousands of individuals. In this study, We describe a modification of the DNA extraction method, in which cetyltrimethylammonium bromide (CTAB) is used to extract DNA from leaf tissues for suitable MAS in rice. We followed the standard 2% CTAB extraction method in all the procedure. In addition we used the 1.2 ml 8-strip tube instead of 1.5 ml E-tubes to fit the 8-multichannel pipette and employ the 96 well plate to use the swing bucket centrifuge. Our modified CTAB DNA extraction method offers several advantages with respect to traditional and simple methods. 1) adult leaf samples collected in paddy field are applicable. 2) 96 leaf samples can be homogenized only one-time by using tungsten carbonate bead and 96well block. 3) semiautomatic loading method using 8-multichannel pipette from DNA extraction to electrophoresis of PCR products. 4) our system can extract about 400 leaf samples per day by only one technicion. Therefore, this method could be useful for marker assisted breeding in rice.

In rice, tillering is an important trait determining yield. To study tillering at the agricultural and molecular aspects, we have examined a spontaneous rice mutant that showed reduction in the number of culms. The mutant was derived from a F6 line of the cross of Junambyeo*4 / IR72. It could produce, on average, 4 tillers per hill in the paddy field while wild-type plants usually have 15. Except the reduced culm numbers, they also show pale green phenotypes. The phenotypes of this mutant were co-segregated as the monogenic Mendelian ratio (χ2 = 0.002, p = 0.969). In order to locate a gene responsible for the rcn phenotype, the mutant with the japonica genetic background was crossed with Milyang21 of the indica background. Bulked segregant analysis was used for rapid determination of chromosomal location. Three SSR markers (RM551, RM8213, and RM16467) on chromosome 4 were genetically associated with the mutant phenotype. Each of the 217 F2 plants was genotyped with simple sequence length polymorphisms. The data showed that RM16572 on chromosome 4 was the closest marker that showed perfect co-segregation among the F2 population. We suggest the new rcn gene studied here name as rcn10t because there was no report which exhibit a rcn phenotype with a pleiotropic effect of pale green (chlorophyll deficiency), and mapped at same position on chromosome 4.