• The Korean Journal of Pesticide Science
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• v.15 no.2
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• pp.188-193
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• 2011

Resistance monitoring for tolyfluanid was conducted over 2 years from 2005 to 2006 with 218 isolates of Botrytis cinerea obtained from infected plants of ginseng. All isolates of B. cinerea were divided into 3 groups such as highly sensitive (HS) group, sensitive (S) group and less sensitive (LS) group to tolyfluanid. HS group was defined as one showing $EC_{50}$ value less than $2.0\;{\mu}g\;mL^{-1}$. $EC_{50}$ value of S group ranged between $2.0\;{\mu}g\;mL^{-1}$ and $18.0\;{\mu}g\;mL^{-1}$, while that of LS group was more than $18.0\;{\mu}g\;mL^{-1}$ Among B. cinerea isolates tested in this study, 174 isolates were included into S group, while 22 isolates were done into HS group. The other isolates belonged to LS group. Botrytis cinerea isolates showed the high correlation of $EC_{50}$ value of mycelial growth with that of spore germination to tolyfluanid. This results could be used for the determination of fungicide resistance and the establishment of strategy for fungicide resistance management.

• Journal of Mushroom
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• v.2 no.2
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• pp.69-75
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• 2004

This study was carried out to investigate effect of $CaCO_3$ treatment on cultivation of oyster mushroom for suppression of green mold disease and for promotion of mycelial growth to stabilize mushroom production in field and laboratory experiment. Treatment of $CaCO_3$ in PDA media promoted mycelial growth of mushroom and suppressed that of green mold. Addition of $CaCO_3$ in rice straw substrate increased mushroom mycelial growth compared with control. In that case, growth of green mold increased up to treated 0.6% $CaCO_3$ but decreased in treatment beyond 0.8% $CaCO_3$. There were some differences on effect of $CaCO_3$ treatment according to green mold species. Trichoderma longibrachiatum was effected but T. virens was not effected by treated $CaCO_3$. Differences among mushroom strains by treated $CaCO_3$ were not shown. It is confirmed that treatment of $CaCO_3$ can promote mushroom mycelial growth but it's not clear in the field. In the result of field test, treatment of $CaCO_3$ in rice straw substrates tended to increase yield and decrease incidence of disease compared with non-treatment. These results suggest that $CaCO_3$ treatment on cultivation of oyster mushroom can be applied to take preventive steps against of green mold disease.

• Journal of Mushroom
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• v.1 no.1
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• pp.48-53
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• 2003

This study was carried out to investigate effect of adding tobacco waste to promote oyster mushroom, Pleurotus ostreatus, mycelial growth and control of Trichoderma disease. Tobacco waste was treated on the surface of rice straw inoculated with oyster mushroom strains. The mycelial growth treated with 0.1g tobacco waste was somewhat faster than non-treatment. In the case of mixed media with 1.0g tobacco waste, mycelial growth was increased compare to control, but adding 2.0 g tobacco waste decreased the mycelial growth. We also treated the tobacco waste on Trichoderma disease. All of the tobacco waste treatment force down the growth of Trichoderma disease. We treated tobacco waste on the surface of rice straw substrates. ASI 2072 mycelial growth was decreased regardless of amount of tobacco waster and method of treatment. Mycelial growth of ASI 2180 was somewhat decreased with treatment of 0.1g and 0.2g In the case of media mixed, mycelial growth of ASI 2072 was decreased in the overall treatment. Mycelial growth of other strains were decreased as only 2.0g treatment. Field test of mycelial growth was conducted using rice straw and waste cotton with substrates. Rice straw culture with treated 3% tobacco waste and cotton waste culture with treated 6% tobacco waste showed the highest yield. There was no effect to Trichoderma disease.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.1 no.2
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• pp.87-96
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• 1968

As the raw material of fish paste, the experiment on shark meats was conducted from July to December 1967 at the Fisheries Research and Development Agency, Pusan, Korea. The result and the conclusion obtained by the experiment are as follows. 1. Much salt-soluble protein was found in the shark meat comparing with to the other fish. 2. Deodorization of shark meat, using less than $0.05\%$ of acetic acid was most preferable for the elasticity and flexibility of its product. 3. Keeping raw material at low temperature was necessary in maintaining its elasticity. 4. In setting shark fish paste, keeping the raw material at $35-40^{\circ}C$ for 40-70 minutes was the most desirable condition. 5. The best temperature and the duration of heating were 40-60 minutes at $89-90^{\circ}C$, Meanwhile, heating at high temperature was preferable for the storage for a long period, but the elasticity and quality has decreased a little accordingly. 6. For the increase of its palatability, adding $30\%$ of yellow corvenia meat or $20\%$ sea eel meat were more preferable. 7. Pre ervation of the product for 20 days at $20^{\circ}C$ or 50 days at $5^{\circ}C$ was possible by adding $0.2\%$ potassium sorbinate to the product as antiseptic.

• Journal of Plant Biotechnology
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• v.36 no.1
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• pp.23-29
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• 2009

We have previously isolated a CCCH type zinc-finger protein gene, OsZF2 (Oryza sativa Zinc Finger 2), from the cold-treated rice cDNA library. To investigate the potential role of OsZF2, transgenic rice lines over-expressing OsZF2 under the control of CaMV 35S promoter have been developed through Agrobacterium-mediated transformation. Elevated level of OsZF2 transcripts was confirmed by RNA gel blot analysis in transgenic rice. Under the 100 mM NaCl condition, the transgenic rice showed significantly enhanced growth rate in terms of shoot length and fresh weight, implicating that OsZF2 is likely to be involved in salt response of rice. In the field condition, however, the transgenic rice showed a dwarf phenotype and flowering time was delayed. Genome expression profiling analysis of transgenic plants using the 20K NSF rice oligonucleotide array revealed many up-regulated genes related to stress responses and signaling pathways such as chaperone protein dnaJ 72, salt stress-induced protein, PR protein, disease resistance proteins RPM1 and Cf2/Cf5 disease resistance protein, carbohydrate/ sugar transporter, OsWAK kinase, brassinosteroid LRR receptor kinase, and jasmonate O-methyltransferase. These data suggest that the CCCH type zinc-finger protein OsZF2 is a upstream transcriptional factor regulating growth and stress responsiveness of rice.

• Research in Plant Disease
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• v.14 no.2
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• pp.95-101
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• 2008

Fungicide resistance of cucumber powdery mildew was screened among the pathogens isolated from diseased plants in main cucumber productuion areas in Gyeonggi Province. Each fungicide from different activity group for the control of powdery mildew were sprayed on cucumber leaves according to application concentration. Each conidia mixed with sterilized water isolated of pathogens were transferred on the cucumber leaf disks treated with each fungicide. At 7 to 9 days after inoculation of pathogen, disease severity was recorded under the microscope. Most of pathogen isolates showed moderate resistance to difenoconazole belonged to DMI group fungicide while some isolates from Osan were resistant even $300{\mu}g/ml$. Isolates from Pyeongtaek, Osan and Yongin area also showed moderate resistance to fenarimol while one isolate showed resistant to fenarimol even $300{\mu}g/ml$. Most of isolates from Pyeongtaek, Osan and Yongin showed highly resistant to azoxystrobin belonged to strobilurin group fungicide. Standard sensitive isolates the minimum inhibition concentration(MIC) value for azoxystrobin showed $200{\mu}g/ml$ while resistance isolates showed above $2000{\mu}g/ml$. Resistant isloates also showed cross resistance among strobilurin group fungicides and low control efficacy in the field test. These results suggest that treatment of strobilurin fungicides should be reduced for the control of powdery mildew.

• Research in Plant Disease
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• v.20 no.2
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• pp.87-94
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• 2014

The fungus Cylindrocarpon destructans is the cause of root rot in many ginseng production areas in Korea. A total of 57 isolates of C. destructans were recovered from diseased roots in a survey of ginseng-growing fields from 2011-2012. Among these isolates, 37% were classified as highly virulent (causing lesions on unwounded mature roots) and 61% were weakly virulent(causing lesions only on previously wounded roots). Radial growth of highly and weakly virulent isolates on potato dextrose agar was highest at $20^{\circ}C$ and there was no growth at $35^{\circ}C$. Mycelial mass production was significantly (P = 0.05) lower at pH 7.0 compared with pH 5.0. To study the effects of pH (5.0 and 7.0) and wounding on disease development, ginseng roots were grown hydroponically in nutrient solution. Lesions were significantly larger (P < 0.01) at pH 5.0 compared with pH 7.0 and wounding enhanced disease by a highly virulent isolate at both pHs. In artificially infested soil, 2-yearold ginseng roots were most susceptible to Cylindrocarpon root rot among all root ages tested (1 to 4 years) when evaluated using a combined scale of disease incidence and severity. Root rot severity was significantly (P<0.05) enhanced by increasing the inoculum density from $3.5{\times}10^2cfu/g$ of soil to $2.0{\times}10^3cfu/g$ of soil.

• Korean journal of applied entomology
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• v.39 no.2
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• pp.73-82
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• 2000

Two Psyllidae species of Cacopsylla pyricola (Foerster) and C. pyrisuga (Foerster)damaging pear trees have been reported in Korea. However, their ecological characteristics and damagepatterns have not been evaluated yet. To establish basic control measures of C. pyricola, field phenology,overwintering ecology, seasonal fluctuation and temperature-dependent development of C. pyricola wereexamined. C. pyricola overwintered under the bark scale of pear trees as winter form adults and theymoved to fruiting twigs from mid-February. Honeydew produced by C. pyricola nymphs and adults asthey feed caused serious black sooty mold on leaves and fruits. The seasonal occurrence of C. pyricolawas different every year. In 1993, characterized by cold temperature and heavy precipitation, C. pyricolapopulation was maintained highly during growing season. However, the population was decreased rapidlyfrom early July in 1994, year of hot and dry weather condition. In 1995, year of average temperature, thedensity of C. pyricola population was decreased during hot months of July and August, and rebuilt up inSeptember and October. The development periods of C. pyricola eggs were 13.33 days at 15"C, 9.32 daysat 20$^{\circ}$C, 7.82 days at 25"C, 6.60 days at 30$^{\circ}$C, and 7.75 days at 35$^{\circ}$C. The development periods ofnymphs were 33.75 days at 15OC, 23.77 days at 20$^{\circ}$C, 15.21 days at 25"C, and 17.40 days at 30$^{\circ}$C. Theirdevelopment periods and mortalities were increased in higher temperatures. The parameters of nonlineardevelopment model, Weibull and linear development models of Cacopsylla pyricola were estimated.models of Cacopsylla pyricola were estimated.

• Korean journal of applied entomology
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• v.14 no.2 s.23
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• pp.59-63
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• 1975

A total of 40 virus infected tobacco plants (Nicotiana tabaccum L.) with various symptom types Were collected from Bucheon and Jeonju area by its symptoms were investigated on the incidence of tobacco mosaic virus (TMV), cucumber mosaic virus (CMV), alfalfa mosaic virus (AMV), potato virus X (PVX) and potato virus Y (PVY) by serological methods. van Slogteren's microprecipitin test was applied for the testing of PVX and PVY from infected plants and Ouchterlony agar double diffusion test was used for CMV, TMV and AMV. Results obtained are as follows: 1. TMV, CMV, AMV, PVX and PVY wcre found to occur on the tobacco plants growing in Korea. 2. The prevalence of each of these viruses among the 40 tobacco plants investigated was in the order of AMV: $(67.5\%)>CMV:(60.0\%)>TMY:(47.5\%)>PVY:(17.5\%)>PVX: (10.0\%).$ 3. In Burley variety, the percentage of infection by TMV was $15\%$, whereas it was as high as $80\%$ in Hicks variety. 4. Among the 40 tobacco plants investigated, $37.5\%$ showed infection with one kind of virus whereas the remaining $62.5\%$, revealed mixed infection with more than two different viruses.

• Research in Plant Disease
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• v.8 no.4
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• pp.239-244
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• 2002

Among 34 isolates of Colletotrichum spp., 20 from red pepper and 14 from apple, only one isolate 2001-45 was identified as the isolate resistant to sterol biosynthesis inhibiting fungicides. EC$_{50}$ values of the isolate 2001-45 were 153.5, 42.7, 34.0, and 17.1 $\mu\textrm{g}$/ml for myclobutanil, tebuconazole, hexaconazole and nuarimol, respectively, The resistance factor of the isolate 2001-45 against the other isolate 2001-44 to 4 above fungicides was ranged from 17 to 57. However, EC$_{50}$ value of the 2001-45 for prochloraz was 0.07 $\mu\textrm{g}$/ml, which was lower than those of the 2001-44 and the isolate JC24. For the fitness test of the 2001-45, mycelial growth, sporulation on PDA and pathogenicity on fruits were investigated. No difference in mycelial growth was found between 2001-45 and 2001-44, but great difference in sporulation. No symptom was developed by 2001-45 even by wound inoculation of pepper fruit. Therefore, this study indicated that the isolate 2001-45 was inferior to the other isolates in the fitness, although the isolate 2001-45 was highly resistant to sterol biosynthesis inhibiting fungicides.