야생벼는 재배벼의 병해충 저항성과 불량환경 적응성 등을 제고할 수 있는 유용한 유전자원으로 평가되고 있다. 농촌진흥청 국립식량과학원에서 국내육성 자포니카 벼 품종인 ‘화성’과 야생벼 O. minuta (BBCC 게놈; Acc.=101141)간의 종간교잡을 통하여 흰잎마름병과 도열병에 저항성인 ‘수원506호’를 육성하였으며, 본 계통에 대한 야생벼 유래 도열병 저항성 유전자의 유전양상 구명 및 유전자위 표지에 대한 연구결과는 다음과 같다.1.반복친인 ‘화성’에 높은 친화성을 발현하는 6개 도열병 균주 검정에서 ‘수원506호’는 반복친 ‘화성’과 5개 비교품종들과 다른 저항성 반응을 보여 이들과 다른 야생벼 유래 도열병 저항성 유전자를 보유하는 것으로 판단되었다.2.분자마커의 유전자형과 도열병 저항성 간의 연관성평가를 수행한 결과, ‘수원506호’의 도열병 저항성에 관여하는 주동유전자위는 12번염색체 중단의 RM101-S10704-RM1337 좌위에 위치하는 것으로 추정되었다.3.STS 마커 S10704에서 확인된 ‘화성’과 ‘수원506호’의 이질적인 유전자형은 해당부위에 야생벼 O. minuta의 염색체 단편이 이입되었다는 것을 증명하였다.4.이 좌위는 적어도 9개의 도열병 저항성 유전자들이 위치하는 것으로 보고된 바 있는데, 추후 정밀분석을 통해 ‘수원506호’의 도열병 저항성 유전자위와 기 보고된 유전자들과의 관계를 분석할 계획이다.

Usually, columns are the key load bearing elements in concrete frame structures. They are typically weak, not to long distance explosive loadings, but to short distance loadings. In this study, the effect of blast loadings occurring within a short distance was examined analytically. Various aspect ratios of column sections with the same sectional area and reinforcement ratio were considered as variables in order to evaluate damage levels. It was found that ratio of residual strength to nominal axial strength of columns decreased as contact area of column to the blast loading became smaller.

Rice blast disease caused by the fungal pathogen Magnaporthe oryzae is one of the most destructive rice diseases worldwide. Resistance to rice blast pathogen mostly shows a quantitative trait controlled by several genes. A total of 13 major blast resistance (R) genes were reported in a number of Korean rice varieties using molecular markers. The Pi-ta gene, which locates near to the centromere of chromosome 12, was haplotyping using 1790 accessions including cultivated and wild varieties in previous research. However, the genetic variations of other R genes in rice still not clear. Three R genes, Pi9, Pia, and Pib on chromosome 6, 11 and 2 respectively, were resequenced among 84 accessions of rice core set. Different types of halotype among the 84 accessions were detected. Some new SNPs and InDels found in exon part of R genes were expected to result into amino acid changes following analysis of the genetic code variations, and the germplam in this rice core set which are resistance to blast were explored. We are expecting to develop the new functional markers and incorporate of resistance genes into existing rice cultivars and finally these apply outcomes in breeding rice resistance to blast diseases.

‘화원5호’는 ‘일품벼’의 유전적 배경에 ‘모로베레칸’의 도열병 저항성 유전자가 이입된 근동질 계통을 육성하기 위해 ‘일품벼’와 ‘모로베레칸’을 교배하고, 계속적인 여교배와 MAS를 병행 실시하여 육성한 계통이다. ‘화원5호’는 ‘일품벼’의 유전적 배경에 염색체 1번, 4번 및 6번에 ‘모로베레칸’의 염색체단편이 이입된 것으로 나타났으며, 염색체 4번에 위치한 ‘모로베레칸’의 단편이 도열병 저항성을 증진시켰다. ‘화원5호’의 출수기는 보통기 재배에서 8월 19일로 ‘일품벼’와 동일한 중생종 품종이며, 천립중은 23.8 g으로 ‘일품벼’와 유사한 수준이었다. 완전미율은 ‘일품벼’에 비해 약간 낮았고, 아밀로스 함량은 ‘일품벼’보다 높았으나 통계적인 차이는 없었다. ‘화원5호’의 정조수량은 2005년부터 2006년간 실시한 생산력검정 시험에서 평균 6.53 MT/ha로 ‘일품벼’ 대비 102% 수준이었다. 4개 지역에서 2개년간의 밭못자리 검정 및 연계재배법을 이용한 도열병 검정 결과, ‘화원5호’는 ‘일품벼’에 비해 도열병 저항성이 증진된 것으로 나타났다. 생산력검정 시험 결과 조사된 형질 중 도열병저항성을 제외한 기타 형질에서는 ‘일품벼’와 유사한 근동질계통으로, 품종보호 출원 조건에 부합하여 ‘화원5호’로 명명하고 품종보호원을 출원하였다.

Ground granulated blast furnace slag is known to be much less quality variation compared to the fly ash can be substituted. Have high salt damage resistance, and chemical resistance of concrete with ground granulated blast furnace slag substitution. The case of NPP concrete using fly ash in concrete, and is defined as less than 20% fly ash utilization. In this paper, consider a resistance to freezing-thawing of currently used to concrete in NPP structures and substitutes for ground granulated blast furnace slag

본 연구에서는 다양한 RC 슬래브의 접촉 발파 실험을 수행하여 내폭 성능을 평가하였다. RC 슬래브의 내폭 성능 향상을 위해 섬유 보강과 외부 CFRP 시트 보강을 도입하였다. 폭발하중 실험은 2,000×1,000×100mm RC 슬래브를 제작하였고, 일반 콘크리트와 강섬유 보강 콘크리트, 하이브리드 PVA 섬유 보강 시멘트 복합체, 초고성능 콘크리트를 적용하였다. 접촉 발파로 생긴 RC 슬래브의 손상 정도를 크레틀, 스폴과 브리치의 직경과 깊이로 평가하였다. 실험 결과를 LS-DYNA 유한요소해석 프로그램과 Morishita 등의 예측식으로 검증하고 비교분석하였다. 분석 결과, LS-DYNA 프로그램을 이용하여 크레틀, 스폴, 브리치의 직경 및 깊이에 대한 개략적인 예측이 가능하며, 폭발하중 하에서 손상부의 거시적 거동을 모사함으로써 부재의 파괴 이력을 나타낼 수 있었다. 국부 손상에 대한 세가지 예측식이 소개되어 있으나 경험식으로써의 한계가 존재하며, 이에 대한 추가 연구가 필요하다고 판단된다.

During the last decade, considerable progress has been made to understand the molecular mechanisms of M. grisea infection in rice plants and 10 rice blast R genes have been identified and characterized via map-based cloning methods. In case of rice germplasm, the genetic backgrounds of each germplasm accessions are not uniform and the evaluation for pathogenicity is difficult. To solve these problems, we applied the single resistance gene markers to rice germplasm accessions. A molecular survey was conducted to identify the presence of major blast resistance (R) gene in 363 accessions of Korea landrace rice germplasm. The results revealed that the resistance gene Pik-p (100%), Pib (98%), Pi-d(t)2 (98%) and Piz (76%) were widely observed in tested rice germplasm, but Pita-2, Pik and Pi39 gene were identified in less than 10 accessions. Most of landrace contain the four or five different resistant genes, but these results was not consist of field nursery screening. 13 accessions were shown the blast resistance in field nursery screening and Pik-p, Pib, Pi-d(t)2 and Piz genes were observed in these accessions. The evaluation results of blast resistance genes in rice germplasm will help in breeding of multi disease resistant varieties.

The objective of this study was to determine the genetic diversities of major rice blast resistance genes among 84 accessions of aromatic rice germplasm. Eighty four accessions were characterized by a dominant 11 set of PCR-based SNP and CAPS marker, which showed the broad spectrum resistance and closest linkage to seven major rice blast resistance (R) genes, Pia, Pib, Pii, Pi5 (Pi3), Pita (Pita-2), and Pi9 (t). The allele specific PCR markers assay genotype of SCAR and STS markers was applied to estimate the presence or absence of PCR amplicons detected with a pair of PCR markers. One indica accession, Basmati (IT211194), showed the positive amplicons of five major rice blast resistance genes, Pia, Pi5 (Pi3), Pib, Pi-ta (Pi-ta2), and Pik-5 (Pish). Among 48 accessions of the PCR amplicons detected with yca72 marker, only five accessions were identified to Pia gene on chromosome 11. The Pib gene was estimated with the NSb marker and was detected in 65 of 84 accessions. This study showed that nine of 84 accessions contained the Pii gene and owned Pi5 (Pi3) in 42 of 84 accessions by JJ817 and JJ113-T markers, which is coclosest with Pii on chromosome 9. Only six accessions were detected two alleles of the Pita or Pita-2 genes. Three of accessions were identified as the Pi9 (t) gene locus.

화원4호'는 '일품벼'의 농업적 특성에 모로베레칸의 도열병 저항성 유전자가 이입된 근동질계통을 육성하기 위해 '일품벼'와 모로베레칸을 교배하고, 계속적인 여교배와 MAS를 병행 실시하여 유망한 계통 CR502-3-2 계통을 선발하였다. 생산력검정 시험 결과 조사된 형질 중 도열병저항성을 제외한 기타 형질에서는 '일품벼'와 유사한 근동질계통으로, 품종보 호원 출원 조건에 부합하여 '화원4호'로 명명하고 품종보호원을 출원하였다. 1. 출수기는 보통기재배에서

본 연구는 국내 수집 잡초성벼에 존재하는 잎도열병 저항성 관련 유전자를 탐색하고, 이 저항성유전자와 연관된 분자마커를 탐색하는 것이다. 도열병에 감수성인 자포니카 품종인 낙동벼와 도열병에 강한 잡초성벼인 강화앵미11을 교잡하여 120개 RILs를 육성하여, 도열병 균주반응과 잎도열병 밭못자리검정을 통한 저항성 유전자 탐색에 이용하였다. 1. 총 45개 도열병 균주를 이용하여 양친들을 검정한 결과, 잡초성벼 강화앵미11은 25개 균주에 대하여 저항성 반응

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.

Field resistance is defined as the resistance that allows effective control of a parasite under natural field condition and is durable when exposed to new races of that parasite. To identify the genes for field resistance against rice blast, quantitative trait loci (QTLs) conferring field resistance in japonica rice cultivars were detected and mapped using SSR markers. QTL analysis was carried out in 190 RILs population from the cross between Suweon365 (moderately resistance) and Chucheong (highly susceptible). Fourteen QTLs for nine blast races inoculated were detected on chromosomes 1, 2, 4, 5, 6, 7, 11 and 12. They explained from 6.4 to 39.7% of total phenotypic variation. Eight QTLs for blast nursery screening in 4 regions for three years were detected on chromosomes 1, 2, 4, 5, 11 and 12. The phenotypic variation was explained by each QTL ranged from 5.9 to 38.0%. Three BC2F5 backcrossed progeny lines were developed to transfer the QTLs into the susceptible cultivar Chucheong as a recurrent parent. A NIL4 containing two QTLs Qbl6.2 and Qbl7 for blast races showed the reaction 6 to 7 in blast nursery in 2007 and 2008, respectively. Two lines NIL143 and NIL93 containing Qbl11.2 and Qbl12.1 for QTLs related with field resistance, respectively, were 3 to 4 reactions in blast nursery.

Fifty-two Korean japonica rice cultivars were analyzed for leaf blast resistance and genotyped with 4 STS and 26 SSR markers flanking the specific chromosome sites linked with blast resistance genes. In our analysis of resistance genes in 52 japonica cultivars using STS markers tightly linked to Pib, Pita, Pi5(t) and Pi9(t), the blast nursery reaction of the cultivars possessing the each four major genes were not identical to that of the differential lines. Eight of the 26 SSR markers were associated with resistant phenotypes against the isolates of blast nursery as well as the specific Korean blast isolates, 90-008 (KI-1113), 03-177 (KJ-105). These markers were linked to Pit, Pish, Pib, Pi5(t), Piz, Pia, Pik, Pi18, Pita and Pi25(t) resistance gene loci. Three of the eight SSR markers, MRG5836, RM224 and RM7102 only showed significantly associated with the phenotypes of blast nursery test for two consecutive years. These three SSR markers also could distinguish between resistant and susceptible japonica cultivars. These results demonstrate the usefulness of marker-assisted selection and genotypic monitoring for blast resistance of rice in blast breeding programs.