• Current Research on Agriculture and Life Sciences
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• v.23
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• pp.33-41
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• 2005

Above 130 accessions of pepper consisting of 50 introductions from Mexico and Nepal, and resistant and susceptible controls were tested for resistance to bacterial wilt and to Phytophthora root rot at seedling stage by artificial inoculation. Aa the results, KC897, KC939, KC936 were newly found resistant to bacterial wilt in addition to already known resistance sources such as KC126, KC350, KC351, KC353. No new sources of resistance to Phytophthora root rot were found among the introductions from Mexico and Nepal.

• Korean journal of applied entomology
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• v.24 no.4 s.65
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• pp.219-222
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• 1986

The inheritance and allelism tests of the genes resistant to bacterial blight in some rice breeding lines and varieties were studied. Resistance to isolate JB 8206 was found to be controlled by a single dominant gene in the rice varieties such as, Cheongcheongbyo, Yeongpungbyo, Nampungbyo, Samgangbyo, Hangangchalbyo, and Milyang 42. The resistance in varieties like Pungsanbyo and Baegyangbyo, to isolates JB 8206 and KN 8298 appeared to be governed by a single dominant gene. Evidence from the allelism test indicates that Pungsanbyo, Cheongcheongbyo, Milyang 30, and Baegunchalbyo may have the same dominant gene for resistance to isolate JB 8206, and that Suweon 312, Baegyangbyo as well as Baegunchalbyo may have the other same dominant gene.

• Horticultural Science & Technology
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• v.19 no.1
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• pp.7-11
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• 2001

A total of 238 accessions of peppers (Capsicum spp.) were evaluated for resistance to powdery mildew (Leveillula taurica (Lev.) Arn) in 1998-1999. KC604, 605, 606 and 608 of C. baccatum, KC616 of C. chinense, and KC638, 640, 641, 642, 643 and 644 of C. pubescens were highly resistant and remained disease-free. KC47-1 (PI244670), KC319-1, KC545, KC320 showed only mild infection compared with susceptible control group, 'Chungok' and others. Therefore, they were considered moderately resistant. Among them, KC47-1, KC319-1 and KC320 are sources of resistance to gray leaf spot caused by Stemphylium spp. while KC47-1 is also resistant to bacterial leaf spot (Xanthomonas campestris pv. vesicatoria (Doidge) Dye). Therefore, they may be used in breeding for multiple resistance to those diseases.

• Proceedings of the Korean Society of Tobacco Science Conference
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• 2000.05a
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• pp.33-33
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• 2000

• Korean journal of applied entomology
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• v.44 no.2
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• pp.151-156
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• 2005

The development of resistance to bifenazate (resistance ratio of egg=40.3 folds) was found in population of the twospotted spider mite, Tetranychus urticae, collected from rose greenhouses in Chilgok, Gyeongbuk Province in December 2000. This population was selected for 4 years with bifenazate treatment (over 150 times), and showed 248.8 folds increase in resistance as compared to susceptible (S) strain. Inheritance of bifenazate resistant strain (R) and cross resistance of this strain to 9 acaricides were investigated. There were differences of susceptibility in the bifenazate concentration-mortality relationships in F1 progenies obtained from reciprocal cross with the S and R strain $(R{\times}S,\;S{\times}R)$. Degrees of dominance were 0.48 and 0.94 in adult females and eggs of $R{\times}S$ and -0.85 and -0.17 in adult females and eggs of $S{\times}R$, respectively. Inheritance type in the F1 progeny of $R{\times}S$ was incomplete dominant, and F1 progeny of $S{\times}R$ was incomplete recessive. These results suggest that inheritance of bifenazate resistance is controlled by a complete dominance. The R strain exhibited cross resistance to acequinocyl and fenpyroximate in adult females, and amitraz, emamectin benzoate, fenpyroximate, milbemectin, pyridaben and spirodiclofen in eggs. However they showed negatively correlated cross-resistance to emamectin benzoate and milbemectin in adult females, and abamectin in eggs.

• Research in Plant Disease
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• v.18 no.4
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• pp.304-309
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• 2012

Fusarium wilt, caused by three races of Fusarium oxysporum f. sp. lycopersici, is one of the most important disease of tomato (Solanum lycopersicum) worldwide. A total of 1,906 tomato accessions were screened for the resistance to Fusarium wilt using I-3 SNP marker and high resolution melting analysis. Results showed that 97 accessions were homozygous resistant, 8 accessions were heterozygous resistant and 1,801 were homozygous susceptible. Accessions containing resistance were identified in 65 accessions of S. lycopersicum var. lycopersicum, 13 accessions of S. lycopericum var. cerasiform, 8 accessions of S. pimpinellifolium, 3 accessions of S. habrochaites, 3 accessions of S. corneliomulleri, 1 accession of S. galapagense, 3 accessions of S. peruvianum, 1 accession of S. chilense. For accurate evaluation of the Fusarium wilt resistance, however, screening to race 1 and race 2 and bio-assay still remain to be evaluated.

• Horticultural Science & Technology
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• v.34 no.5
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• pp.779-789
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• 2016

A total of 33 accessions of pepper (Capsicum spp.), including previously reported and newly discovered sources of resistance to bacterial spot caused by Xanthomonas euvesicatoria, were evaluated for their resistance to bacterial spot. The selected accessions were then grown and their horticultural characteristics were recorded. In a test for hypersensitive resistance (HR) to four races (P1, P3, P7, P8) of the pathogen found in Korea, KC00939 and Chilbok No.2, which carry the Bs2 gene, exhibited a hypersensitive response to all four races, as expected. Chilbok No.3, which carries the Bs3 gene, showed a hypersensitive reaction to race 1 and 7, as expected. KC00939 exhibited a high ASTA color value and tolerance to multiple infections from a viral complex of Cucumber mosaic virus (CMV) and Broad bean wilt virus (BBWV). Thus, this accession represents a promising genetic resource for breeding cultivars with multiple disease resistance and strong red coloration. KC01327, KC01617, KC01015, KC01760, KC01779, KC01137, KC01328, KC01006, KC00127, KC01704, and KC00995 did not exhibit hypersensitivity but showed a high level of general resistance when evaluated by spray inoculation. KC01617, KC01760, KC01779, KC01137, KC01704, and KC01777 are newly identified sources of resistance to bacterial spot. The previously and newly identified sources of resistance to bacterial spot evaluated in this study, including information about their resistance to CMV and BBWV complex in the field, the contents of pungent and sweet taste components, and the color values of dry fruits, will be useful for breeding pepper cultivars with resistance to bacterial spot.

• Journal of Plant Biotechnology
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• v.49 no.3
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• pp.240-249
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• 2022

Measuring chlorophyll fluorescence (CF) is a useful tool for assessing a plant's ability to tolerate abiotic stresses such as drought, waterlogging and high temperature. Korean ginseng is highly sensitive to water stress in paddy fields. To evaluate the possibility of non-destructively diagnosing waterlogging stress using chlorophyll fluorescence (CF) imaging techniques, we screened 57 ginseng accessions for waterlogging tolerance. To evaluate waterlogging tolerance among the 2-year-old Korean ginseng accessions, we treated ginseng plants with water stress for 25 days. The physiological disorder rate was characterized through visual assessment (an assigned score of 0-5). The physiological disorder rates of Geumjin, Geumsun and GS00-58 were lower than that of other accessions. In contrast, lines GS97-62, GS97-69 and GS98-1-5 were deemed susceptible. Root traits, chlorophyll content and the reduction rates decreased in most ginseng accessions. Further, these metrics were significantly lower in susceptible genotypes compared to resistant ones. All CF parameters showed a positive or negative response to waterlogging stress, and this response continuously increased over the treatment time among the genotypes. The CF parameter Fv/Fm was used to screen the 57 accessions, and the results showed clear differences in Fv/Fm between the susceptible and resistant genotypes. Susceptible genotypes had an especially low Fv/Fm value of less than 0.8, reflecting damage to the reaction center of photosystem II. It is concluded that Fv/Fm can be used as a CF parameter index for screening waterlogging stress tolerance in ginseng genotypes.

• 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.

• Horticultural Science & Technology
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• v.30 no.2
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• pp.185-191
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• 2012

For initiation of resistance breeding program of the red pepper, 21 PR ($Phytophthora$ resistance) cultivars, 36 cultivars collected from USA and 'Supermanitta' which is a susceptible cultivar against phytophthora blight were assayed against phytophthora blight, powdery mildew, and anthracnose. For seedling assay of phytophthora blight, three different mating type strains of $Phytophthora$ $capsici$ were used (A1, A2, Sterile). The result showed that most of the pepper of PR cultivars were resistance or moderately resistance at each mating type. 'Yeokganghongjanggun' was resistant to all three $P.$ $capsici$ strains and 'PR-Datta' and 'PR-Manitta' were resistant or moderately resistant at each type. In case of the collected cultivars, 'NuMex J.E.Parker', 'Omni Color', and 'SCM334' were resistant to all the three types and some cultivars including 'Sweet Banana' and 'Tabasco' were moderately resistant to each type fungi. 'Orange Habanero' and 'Black Cuban' were resistant to powdery mildew and 'Supermanitta' and 'PR Keumdong' were moderately resistant, while 'Santa Fe Grande', 'NuMex Pinata' and 'Puya' were very susceptible. In the case of anthracnose, 'Aji Limon' and 'Capsicum baccatum var. pendulum 3-4' were resistant and 'Pobalno', 'Omni Color', 'Negro', 'Mesilla', 'Mulato', 'Bhut Jolokia', 'Big Dipper', 'Black Cuban', 'NuMex Pinata', and 'NuMex Big Jim' were moderately resistant. The most PR cultivars except 'Taesan' were susceptible or very susceptible. These resistant individuals identified through this experiment can be used as sources of resistance to pepper pathogens in the future breeding programs.