• Korean Journal Plant Pathology
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• v.14 no.3
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• pp.217-219
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• 1998

Of over 100 accessions of pepper tested, MC 4 and MC 5, PBC631, PI322727, PI358812, PBC066, Kerting, PI322726, PI369994, PI377688, CMS-B, PI322728, and Jatilaba showed similarly high level of resistance to bacterial wilt (Ralstonia solanacearum).

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.112-112
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• 2017

Rice blast caused by Magnaporthe oryzae is one of the most serious diseases that affect the quantity and quality of rice production. The use of resistant rice varieties would be the most effective way to control the rice blast. However R gene incorporation into the rice variety takes time and pathogen could overcome the R gene effects after for a while. For monitoring the rice blast resistance gene distribution in Korean varieties, the four major blast resistance genes against M. oryzae were screened in a number of Korean rice varieties using molecular markers. Of the 120 rice varieties tested, 40 were found to contain the Pi-5 gene, 25 for the Pi-9 gene, 79 for Pi-b and 40 for the Pi-ta gene. None of these rice varieties includes tested 4 R genes. 3 R genes combination, Pi-5/Pi-9/Pi-b, Pi-5, Pi-9.Pi-ta, or Pi-9/Pi-b/Pi-ta were found in 12 varieties, the rice blast disease severity were showed as resistant in the rice verities containing Pi-9/Pi-b/Pi-ta R genes combination, respectively. Also pathogenic diversity of M. oryzae isolates collected in the rice field from 2004 to 2015 in rice field in Korea were analyzed using rice blast monogenic lines, each harboring a single blast resistance gene. Compatibility of blast isolates against rice blast monogenic lines carrying the resistance genes Pi5, Pi9, Pib, and Piz showed dynamic changes by year. It indicates that pathogen has high evolutionary potential adapted host resistances to increase fitness and would lead to rice blast resistance bred into the cultivar becoming ineffective eventually.

• Current Research on Agriculture and Life Sciences
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• v.9
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• pp.127-133
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• 1991

PI201232, a pepper line resistant to Phytophthora capsici Leonian, was crossed with PI2713222 and P1163192, resistant to Xanthomonas campestTis pv. vesicatoria (Doidge) Dye and inheritance of the resistance to each disease and genetic relationship between the two disease resistances was studied. Non-hypersensitive resistance to race 3 of X. c. pv. vesicatoria of PI271322 was inherited in a quantitative mode. Resitance to P. capsici of PI201232 was inherited in a mode close to two dominant alleles. Hypersensitive resistance to race 1 of X. c. pv. vesicatoria of PI271322 was inherited in a mode of single dominant allele. PI 163192 was consistently resistant to both race 1 and race 3 of X c. pv. vesicatoria and the resistance was inherited in a quantitative mode with high dominance effect. Resistance to X. c. pv. vesicatoria was inherited independently from resistance to P. capsici.

• The Plant Pathology Journal
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• v.16 no.2
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• pp.105-109
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• 2000

The Pi-b is the rice gene conferring race specific resistance to the blast fungus Magnaporthe grisea race having a corresponding avirulence gene, AVR-Pi-b. All resistant cultivars have two copies of the Pi-b gene, but susceptible cultivars have a single copy of the gene. About 1 Kbp insertion sequence was detected in the open reading frame of the Pi-b gene from the susceptible cv. Nipponbare. The nature of insertion sequence was identified as a solo long terminal repeat (LTR) of new rice Tyl-copia-like retrotransposon. LTR was widely distributed in the rice genome. Various types of different patterns of restriction fragment length polymorphism of LTR were detected in indica cultivars, whereas a single type was detected from japonica cultivars. The insertion of LTR sequence in the Pi-b gene in the susceptible cultivar suggested that retrotransposon-mediated insertional mutation might played an important role in the resistance breakdown as well as evolution of resistance genes in rice.

• Molecules and Cells
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• v.42 no.9
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• pp.637-645
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• 2019

Effector-triggered immunity (ETI) is an effective layer of plant defense initiated upon recognition of avirulence (Avr) effectors from pathogens by cognate plant disease resistance (R) proteins. In rice, a large number of R genes have been characterized from various cultivars and have greatly contributed to breeding programs to improve resistance against the rice blast pathogen Magnaporthe oryzae. The extreme diversity of R gene repertoires is thought to be a result of co-evolutionary history between rice and its pathogens including M. oryzae. Here we show that Pii is an allele of Pi5 by DNA sequence characterization and complementation analysis. Pii-1 and Pii-2 cDNAs were cloned by reverse transcription polymerase chain reaction from the Pii-carrying cultivar Fujisaka5. The complementation test in susceptible rice cultivar Dongjin demonstrated that the rice blast resistance mediated by Pii, similar to Pi5, requires the presence of two nucleotide-binding leucine-rich repeat genes, Pii-1 and Pii-2. Consistent with our hypothesis that Pi5 and Pii are functionally indistinguishable, the replacement of Pii-1 by Pi5-1 and Pii-2 by Pi5-2, respectively, does not change the level of disease resistance to M. oryzae carrying AVR-Pii. Surprisingly, Exo70F3, required for Pii-mediated resistance, is dispensable for Pi5-mediated resistance. Based on our results, despite similarities observed between Pi5 and Pii, we hypothesize that Pi5 and Pii pairs require partially distinct mechanisms to function.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.56 no.4
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• pp.329-341
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• 2011

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.

• Journal of Information Technology Applications and Management
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• v.14 no.4
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• pp.199-219
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• 2007

This research analyze the impact factors that affect the PI resistance of securities brokerage salespersons during Process Innovation in securities companies focusing on the broker's individual personality. After reviewing some related literatures, a survey was conducted at a domestic securities company with the derived factors from a focus group of securities salesmen with over 10 year work experience. The results show that broker's individual propensity to innovation, individual customer relationship and individual flexibility are closely related to the PI resistance. By controlling such factors for salespersons, securities companies can boost the ability to meet and control the changing situation and management innovation.

• Current Research on Agriculture and Life Sciences
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• v.20
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• pp.83-90
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• 2002

Resistance to Phytophthora Capsici and horticultural characteristics of selections from the resistance sources such as PI123469, PI201234, PI201232, AC2258 (=Line 29), CM334, KC268, KC358, KC820, KC821, KC822, KC823 (Line 29), KC462, KC463, KC464 were evaluated and recorded in the process of seed increase. Selections of PI123469, PI201234, PI201232, AC2258, KC823 (Line 29 = AC2258) of them showed the highest level of resistance. A considerable difference in the level of resistance was observed between lines selected from the same sources. The variation between selections derived from the same source was thought to be attributable to natural cross-pollination that may have occurred during the seed increase. Therefore, securing self-pollinated seed by wrapping the flower buds before anthesis would be necessary to obtain genetically pore resistant lines. The next alternative would be to increase the seed in small net houses for single line or field cage.

• Current Research on Agriculture and Life Sciences
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• v.4
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• pp.7-11
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• 1986

Nine Korean local cultivars and 34 PI lines of pepper were tested for resistance to anthracnose (Colletotrichum dematium). Red ripe fruits were harvested, punctured and inoculated by spraying and dropping a conidial suspension of Colletotrichum dematium. Resistance was evaluated by measuring the diameter of ripe rot lesions developed on and around the puncture. The results obtained are as follows : 1. PI 201232, PI 224451, PI 257044, PI 257119, PI 257099, PI 224433, PI 244668, PI 257102, PI 173877, Namji, Cheongryong, and Seodong were the least diseased and considered to be resistant. 2. PI 241670, PI 244670, and PI 224423 were the most diseased and considered to be susceptible. 3. Others were in between the two extremes and considered to be intermediate.

• Korean Journal of Breeding Science
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• v.40 no.3
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• pp.215-222
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• 2008

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.