• Korean journal of applied entomology
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• v.55 no.4
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• pp.389-403
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• 2016

Sugar beet nematode (Heterodera schachtii Schmidt) was first detected in 2011, in Chinese cabbage grown in the highland areas of Korea. Chemical control of the nematode by nematicides is not feasible due to its cyst-forming characteristics; therefore, the cultivation of non-host crops is a preferable alternative to utilize nematode-infected fields. In this study, a total of 276 plant cultivars belonging to 18 different families were screened to evaluate their resistance to the nematode. Based on the number of cysts formed following nematode inoculation, the tested crops were classified into 3 levels: susceptible, moderately susceptible, and resistant/immune. Among the 276 cultivars tested, 106 cultivars were susceptible, 40 cultivars were moderately susceptible, and 130 cultivars were resistant/immune. Among the resistant/immune cultivars, cyst formation was not observed on eggplant, tomato, lettuce, perilla, carrot, celery, watermelon, oriental melon, cucumber, pumpkin, chives, onion, welsh onion, balloon flower roots, deodeok (Codonopsis lanceolata), Jandae (Adenophora triphylla), and bean. Therefore, these plants are regarded as immune to the cyst nematode. However, many crops belonging to Solanaceae, Asteraceae, Chenopodiaceae, and Poaceae families showed moderate susceptibility or immunity, depending on the crop or cultivar. This study provides a basis for alternative crop recommendations for sugar beet nematode cyst-infected farms in Chinese cabbage production areas.

• Journal of Korean Society of Forest Science
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• v.32 no.1
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• pp.16-20
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• 1976

Employing 7-15 resistant and 8-15 susceptible Japanese black pine (Pinus thunbergii Parl.) trees to pine gall midge (Thecodiplosis japonensis Uchida et Inouye) as samples, needle monoterpenes were analysed by GLC in January and June, and observation was made on the oviposition preference. Following results were obtained. 1. In January, the resistant trees showed higher contents of myrcene, limonene, ${\beta}$-phellandrene and terpinolene but lower contents of ${\alpha}$-and ${\beta}$-pinene and camphene compared to the susceptible trees. But in June, ${\alpha}$-pinene, camphene, limonene, ${\beta}$-phellandrene and terpinolene were higher and the content of ${\beta}$-pinene and myrcene were lower in the resistant trees than the susceptible trees. 2. The content of limonene was higher by the 6.8 percent and the content of ${\beta}$-pinene was lower by the 9.2 percent in the resistant trees than in the susceptible trees in June. 3. No preference for oviposition was found between resistant and susceptible trees. But in the resistant trees gall formation rate was quite lower than the susceptible trees. It was considered, therefore, that limonene and ${\beta}$-pinene content in the needle might be used as an indicator of the resistant Japanese black pine to the pine gall midge regardless of season.

• Korean journal of applied entomology
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• v.21 no.3 s.52
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• pp.113-122
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• 1982

Appressorial formation of Pyricularia oryzae on leaves showed no marked difference between highly resistant Tongil and susceptible Norm No. 6. Race N-2 of the blast fungus penetrated directly into motor cells of susceptible cultivar Norm No. 6, later extensively spreading hyphae were developed, while in the cultivar Tongil, after penetration, no further hyphal extension resulted. In discoloration of infected tissues, the highly resistant cultivar Tongil not only discolored rapidly, but also the percentage of discolored cells was higher than the susceptible cultivars, Jinheung and Norm No. 6. The respiratory rate, was generally higher in infected tissue than in healthy tissue. No significant difference in the respiration rate of resistant Suwon No. 180 was not found between the infected and healthy leaf tissue, whereas, in susceptible Jinheung, a marked increase in respiratory rate was caused by blast infection. The respiratory rate increased at the appearance of the first visible symptom in all cultivars resistant or susceptible. Higher peroxidase activity was found in infected tissues as compared with healthy tissue. Peroxidase activity increased in resistant and susceptible reactions. Particularly, in resistant reaction, the increase of the activity was more pronounced. In highly resistant reaction, there was no difference in peroxidase activity between healthy and infected tissues. Ascorbic acid oxidase, hydroquinone oxidase and catechol oxidase had the same trend as the peroxidase. In contrast, activity of catalase rather decreased in leaf tissues infected with compatible races of the fungus.

• Korean journal of applied entomology
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• v.5_6
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• pp.47-54
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• 1968

In order to develop an effective control measure for the rice stripe disease, methods of testing for resistance and selection of resistant varieties among the leading varieties were investigated. For use as a parent in breeding for resistant variety to the disease, total of 410 rice varieties were tested. 1. Disease occurrence was higher at group inoculation than that of individual inoculation in comparing the inoculation methods. 2. In both methods, Lacrose responded susceptible; Zenith and St. No. 1 resistant, and the rest moderate. 3. Suseptible symptom type A was prevalant among the susceptible varieties, while resistant symptom type C was abundant among the resistant varieties, There was no difference between the inoculation methods. 4. 410 rice varieties tested could he divided into 3 groups as susceptible (21 varieties), moderate (377 varieties) and resistant (12 varieties). Resistant varieties wers St. No. 1 and 2, Shin-2, Gulfrose Bonnet, Arkrose, Sun Bonnet, Zenith, Yeechunchilichal, Norm-24, Opaikjoke, Yangchubatchal and Nonglimana-1, Nams-97,-149, -159, -216. -265, Iri-243, -265, Kanchuk -5, -7, -8, -10, -41, -43, -47, -50, Suwon-56, -77, Norin-22, Cod-4. Lacrose and Chukna were susceptible. 5. There was slight differance in the disease occurrence in regard to maturing period. However late varieties seem to be more resistant than early or medium varieties. The medium varieties seem to be susceptible. Most of the introduced varieties from foreign countries and the upland cultivated varieties were resistant. 6 Among the leading varieties, Shin-2 in Kangwon-Do was resistant, Kosi in Choongchung-Do, was susceptible, aad the others were moderate.

• Animal Bioscience
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• v.35 no.7
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• pp.964-974
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• 2022

Objective: The highly pathogenic avian influenza virus (HPAIV) is a threat to the poultry industry and economy and remains a potential source of pandemic infection in humans. Antiviral genes are considered a potential factor for studies on HPAIV resistance. Therefore, in this study, we investigated gene expression related to the mitogen-activated protein kinase (MAPK) signaling pathway by comparing non-infected, HPAI-infected resistant, and susceptible Ri chicken lines. Methods: Resistant (Mx/A; BF2/B21) and susceptible Ri chickens (Mx/G; BF2/B13) were selected by genotyping the Mx and BF2 genes. Then, the tracheal tissues of non-infected and HPAIV H5N1 infected chickens were collected for RNA sequencing. Results: A gene set overlapping test between the analyzed differentially expressed genes (DEGs) and functionally categorized genes was performed, including biological processes of the gene ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) pathways. A total of 1,794 DEGs were observed between control and H5N1-infected resistant Ri chickens, 432 DEGs between control and infected susceptible Ri chickens, and 1,202 DEGs between infected susceptible and infected resistant Ri chickens. The expression levels of MAPK signaling pathway-related genes (including MyD88, NF-κB, AP-1, c-fos, Jun, JunD, MAX, c-Myc), cytokines (IL-1β, IL-6, IL-8), type I interferons (IFN-α, IFN-β), and IFN-stimulated genes (Mx1, CCL19, OASL, and PRK) were higher in H5N1-infected than in non-infected resistant Ri chickens. MyD88, Jun, JunD, MAX, cytokines, chemokines, IFNs, and IFN-stimulated expressed genes were higher in resistant-infected than in susceptible-infected Ri chickens. Conclusion: Resistant Ri chickens showed higher antiviral activity compared to susceptible Ri chickens, and H5N1-infected resistant Ri chickens had immune responses and antiviral activity (cytokines, chemokines, interferons, and IFN-stimulated genes), which may have been induced through the MAPK signaling pathway in response to H5N1 infection.

• Textile Coloration and Finishing
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• v.8 no.5
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• pp.76-83
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• 1996

Fragrant microcapsules were prepared by in situ polymerization using urea-formaldehyde prepolymer. Lemon oil and migrin oil as susceptible materials were used. The diameter and distribution of the microcapsule were controlled by several factors, such as wall material, core material content, emulsion agent and stirring speed, respectively. Susceptible cotton fabrics with fragrant release functionality were successfully produced by using microcapsule containing fragrant materials.

• Korean Journal of Agricultural Science
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• v.15 no.1
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• pp.1-7
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• 1988

Out of 24 isolates of Alternaria collected from pear leaves, only 7 isolates from cv. Nijiseiki leaves were specifically pathogenic to susceptible pear cultivar(Nijiseiki). Other isolates from cv. Chojuro, Oksankichi and Sinko did not show any pathogenicity to pear leaves. Pathogenic isolates of Alternaria kikuchiana produced host-specific toxin (AK-toxin) in liquid culture which caused veinal necrosis only on susceptible pear leaves, while nonpathogenic isolates did not produce this toxin. Varietal susceptibility among pear cultivars to the pathogen was investigated by evaluating HST (AK-toxin) sensitivity of pear leaves, as a substitute for spore inoculation. AK-toxin which the fungus produces was toxic to pear cultivars susceptible to the pathogen such as Isipsegi and Sinsu, but was harmless to resistant pear cultivars such as Chojuro, Oksankichi, Niitaka etc. Changes in disease susceptibility and toxin sensitivity of pear leaves with aging was investigated. Disease susceptibility and toxin sensitivity in cv. Sinsu leaves appeared to vary with leaf aging; the young leaves were visibly susceptible, but older leaves (more than 2 week old leaves) became resistant.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.48 no.6
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• pp.501-505
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• 2003

The growth characteristics and damage of naked barley infected with barley yellow mosaic virus (BaYMV) were investigated between resistant and susceptible varieties in habitual field plot of BaYMV BaYMV of the barley plants with typical disease symptom were identified by enzyme linked immunosorbent assay (ELISA) test. The visual degree (0-9) based on disease symptoms of BaYMV was different as 9 and 1 between susceptible variety Baegdong and resistant variety Naehanssalbori, respectively. Susceptible variety, Baegdong showed significant damage in culm length, number of kernel per spike and tiller per square meter but not in 1,000 kernel weight, so these results caused yield reduction to only 80% comparing to the control. Seed germination did not affected by BaYMV infection both in susceptible and resistant variety. In grain quality test, abortive grain yale and crude protein content were significantly increased compared to the control. The relationships between BaYMV infection and growth characteristics showed the negative correlations in culm length, number of tiller, 1000 kernel weight and yield, but it showed the positive correlation in crude protein contents. These results implied that BaYMV can affect not only barley growth and yield but grain quality.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.4
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• pp.382-390
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• 1999

In order to identify the responses of Korean soybean cultivars to sudden death syndrome (SDS), forty-two Korean cultivars and three check cultivars (Hartwig and PI 520733 are resistant; Hartz 6686 is susceptible) were tested with sorghum seed inoculum infested with Fusarium solani f. sp. glycines isolate 171 in the greenhouse. This isolate has blue pigment cultural shape on potato dextrose agar (PDA) medium. All Korean cultivars inoculated with F. solani isolate 171 showed the typical SDS symptoms and disease severity on soybean leaves in each cultivar varied at 4 weeks after inoculation. Nine cultivars were included in the most SDS susceptible group and six cultivars were included in the most susceptible group based on Duncan＇s multiple range tests (P$\leq$0.05). In results of the LSD analysis for SDS the resistant group, a total of twenty-five Korean cultivars were included in the same SDS resistant group as PI 520733 or Hartwig and fourteen Korean cultivars were included in the same SDS susceptible group as Hartz 6686. In the second experiment, ten Korean cultivars, ten U.S. cultivars, and one introduced line were compared in the same way as the first experiment Disease severity ranking of check cultivars, Hartwig, PI 520733, and Hartz 6686, were the same as in the first experiment. Within Korean cultivars, seven cultivars showed the consistent severity proportions of leaf symptoms. Disease rankings of these cultivars in this experiment were the same as those in the first experiment. Three US cultivars: Hartwig, Hartz 5454, and Forrest, three Korean cultivars： Keunolkong, Myeongjunamulkong, and Jinpumkong 2, and one introduced line, PI 520733, were included in the highest SDS resistant group. Shinphaldalkong 2, Milyang 87, and Samnamkong consistently showed the highest SDS susceptibility in both experiments. Average disease severity in the first and the second experiment were 49.56% and 45.39%, respectively.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.57 no.4
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• pp.365-372
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• 2012

Native of soybean aphid (Aphis glycines Matsumura) is an Asia and aphid is one of the dangerous pests in soybean [Glycine max (L.) Merr.]. High density aphid populations can reduce crop production by causing severe damage. The objective of this study was evaluation of resistance to the soybean aphid in soybean cultivars and germplasms. A total of fifty five soybean cultivars or germplasms, including two susceptible and two resistant check varieties, were infested to evaluate their resistance in the field cage and greenhouse test by aphid colonies which derived from wild collected one soybean aphid biotype in Korea. The average number of reproduced soybean aphid was evaluated with 62.7 aphids in the resistant check variety PI 567598B and also estimated with 1,807 aphids for susceptible check variety Williams 82. In soybean varieties and germplasms, the average reproduced soybean aphid populations ranged from the lowest 497 aphids for Junjeori to the highest 3,862 aphids for Mansu. About seventy six percent of soybean cultivars and germplasms were shown high density soybean aphid populations when compared with another susceptible check variety PI 567543C in the field cage test. From the greenhouse test to evaluate aphid index, 87.3% of soybean cultivars or germplasms presented aphid index with 9.0. No soybean cultivars and germplasms were observed with soybean resistant phenotype when regarded a aphid resistant level as less than 10% aphid reproductions compared with susceptible check Williams 82. Although no Korean soybean cultivars were identified with resistant trait to the soybean aphid, we found one great resistant genetic resource PI 567598B in this study. This result will be helpful to further study for providing useful genetic information for soybean researchers.