• The Korean Journal of Pesticide Science
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• v.12 no.4
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• pp.335-341
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• 2008

In this study, hexaconazole 5% SC, an ergosterol biosynthesis inhibitor, was tested on groundnut with its recommended ($500\;mL\;ha^{-1}$) and higher ($2,000\;mL\;ha^{-1}$) concentrations under greenhouse conditions in India. Its influence on biochemical constituents of groundnut plants was assessed apart from its disease management potential against late leaf spot caused by Phaeoisariopsis personata (Berk and Curt). Likewise, leaf samples were collected from hexaconazole 5% SC-sprayed plants at different time intervals. Thereafter, their analyses showed considerable differences in the plant constituents, such as chlorophyll, soluble protein, and total phenol contents and the activity of nitrate reductase enzyme. The induction activity of defense-related enzyme, peroxidase, was also analyzed. However, no difference was observed in the isozymic pattern. Moreover, the ground kernels collected from treated plants also showed no difference in the estimated carbohydrate and other constituents.

• The Korean Journal of Pesticide Science
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• v.5 no.1
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• pp.1-11
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• 2001

Climate in the year of 2000 was characterized as a long severe drought in tile spring, unusually high and low temperature in summer, two times of typoons, and floods by heavy rains in fall. Rice leaf and panicle blast and bacterial grain rot occurred severely comparing with 1999 and Bipolaris leaf spot spread over tile country. Phytophthora blight and anthracnose in red-pepper became epidemic especially in the late season causing severe yield losses. Tomato fusaruim wilt, CGMMV, powdery mildew, and sudden wilt syndrom of cucurbits and strawberry powdery mildew were also severe in 2000. In garlic, sclerotium rot occurred severely mainly due to the frequent rainfalls in planting time and much snowfalls in 1999's winter. Spring potato had severe infection of viruses due to a long spring drought, and fall potato had high incidence of bacterial soft rot and bacterial wilt due to fall floods by heavy rains. In sweet potato fusarium wilt was the most severe as in other year. Disease incidence of apple and pear trees was rotatively mild compared with previous years. In wheat and barley, Gibberella petch rarely occurred because of spring drought.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.4 no.1
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• pp.109-114
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• 1968

In order to investigate the growth pattern of sugar beet in Korea, this experiment was conducted using variety GW 359 at Tae-kwan-ryong, Suwon and Cheju. The results are summarized as follows; 1. At Tae-kwan-ryong, early growth stage was relatively long and during higher growing stage plants showed resistance to leaf spot disease, and vegetative maturing started from about September 15th. Top and root growth showed normal curve but it is considered that the early maturing variety will reduce the early growing period and prolong the vegetative maturing period. 2. At Suwon, the growth of top part was favorable until late of July but hereafter leaf spot disease brought death to the 25-35 leaves of top part and regenerated again in October. Consequently, sugar content of root showed changes from decrease to increase. Root weight increased from July to harvest season continunousely but showed abnormal growing curve. This indicates that Suwon is not proper place for sugar beet cultivation. 3. At Cheju, early growing stage was shorter about 15 days than that of Tae-kwan-ryong. Normal growth and long-maturing days favored the sugar accumulation in roots. But it is necessary to introduce non-bolting variety in autumn-winter season culture. 4. Sugar beet could be cultivated economically at Tae-kwan-ryong with 600-800 meter altitude for summer crop and at Cheju for winter crop, but Suwon is considered to be unfavorable for sugar beet.

• Korean Journal of Organic Agriculture
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• v.23 no.4
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• pp.897-909
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• 2015

This study was conducted to evaluate the effect of weed control on disease incidence, plant growth and fruit quality, and to provide effective method to farmers at the vineyard. At the raincoat greenhouse cultivating 'Campbell Early', several weed controlling methods were compared to the control. Mean temperature of plots between soil covering (C.B., W.F., S.N., P.F. and R.H.) and non soil covering (M.W.2, M.W.3 and U.T.) were similar with $26.2^{\circ}C$ (July) and $25.8^{\circ}C$ (Aug.), but humidity of soil covering was sharply decreased in late-July under 40%. Soil water were all higher in soil covering plots than that of non-soil covering, however, soil temperature was recorded lower in soil covering plots. Disease incidence of Peudocercospora vitis according to soil coverings had effect on black plastic film mulching by decreasing grapevine leaf spot to 85% in July, 69% in August, compared to the control, with showing the smallest lesion incidence in FMB. Among growth characters, internode length and internode width of black plastic film mulching was higher than that of the control. SPAD value of black plastic film mulching was recorded the highest. It was not significant among the treatments, but brix was recorded highly in black plastic film mulching with $14{\sim}15^{\circ}Brix$.

• Korean Journal of Breeding Science
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• v.49 no.3
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• pp.224-229
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• 2017

A new peanut variety 'Daan'(Arachis hypogaea ssp. hypogaea L.) was developed at the Department of Southern Area Crop Science, National Institute of Crop Science (NICS) in Milyang 2014. This was developed from the cross between 'Iksan 31' with Virginia typed short stem and 'Dakwang' with Shinpung-typed larger grain. 'Daan' which is a Shinpung plant type had 13 branches per plant and its length of main stem was 44cm. Each pod has two grains with brown testa and long ellipse-shaped large kernel. Its yield components showed 34 pods per plant, 127 g of 100-seed-weight and 75% of pod shelling ratio in the regional yield trials (RYT). Seed quality showed 47.8% of crude oil and 28.3% of protein content. This variety showed resistant to early leaf spot and had more resistant to late leaf spot, stem rot and lodging, compared to reference variety. In the regional yield trials for 3 years 'Daan' was more productive than reference variety by 16% with 5.00 MT/ha for grain production.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.100.1-100
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• 2003

A dctA gene encoding a protein with identity to a C4-dicarboxylate/H+ was cloned from a beneficial biocontrol bacterium, P. chororaphis O6. Expression of the dctA was induced in minimal medium by several organic acids and was repressed by glucose. Highest expression was observed in early-log cells grown on fumarate and succinate with decline as cells approached late-log phase. The dctA transcript accumulated weakly when cells were grown on malate but strong expression was observed with benzoate. Expression of the dctA transcript was repressed in early-log cells upon addition of glucose to fumarate, but was detected as the cell culture aged. A dctA-deficient mutant of O6, constructed by marker exchange mutagenesis, did not grow on minimal medium containing succinate, benzoate, or fumarate, and growth on malate was delayed. The dctA mutant and wild type grew equally on glucose. The dctA mutant on cucumber roots in sterilized potting soil was colonized at levels comparable to those of the wild type, but induction level of disease resistance by the mutant against target leaf spot disease was decreased. These results may indicate that the dctA is essential for utilization of certain organic acids and its expression is controlled by the availability of sugars. In addition, the dctA is not essenitial for cucumber root colonization, but important for induction of disease resistance.

• Korean Journal of Breeding Science
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• v.41 no.4
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• pp.543-546
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• 2009

Intermediate parent "Wonkyo Ga-Dangwagi 1" (Malus domestica Borkh.) was released from Fruit Research Division, National Institute of Horticultural & Herbal Science, Korea in 2008. It was derived from the cross between "Starkrimson" and columnar type "McIntosh Wijcik" in 1992 after selection tests from 2000 to 2008. Trees are moderately vigorous and have spreading branching habit. It bears abundant flower buds on one-year-old branches and fruits mainly on spurs or short branches. Harvesting time of this variety is late September, 7 days later than that of "Hongro" in Suwon. The fruit is conical to narrow conical in shape and bright red in skin color. Fruit size is small with weight of 200~240g on an average and fruits have $14^{\circ}Bx$ soluble solid and medium acidity. It is moderately susceptible to alternaria leaf spot (Alternaria alternata). "Wonkyo Ga-Dangwagi 1" is a promising apple cultivar and will appeal to young people with good sugar-acid balance.

• Korean journal of applied entomology
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• v.20 no.3 s.48
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• pp.135-145
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• 1981

Vegetables including Chinese cabbage and radish have been grown in alpine areas such as Muju, Namweon, Jinan and Jangsu during the shortage period of vegetables. The incidence of various diseases, environmental factors such as temperatures and rainfalls, and aphid populations as virus vector were observed at 10-day intervals from July to September in those areas. Disease incidence showed no significant difference among locations. Major diseases in Chin ese cabbage were bacterial soft rot, white spot, downy mildew, mosaic virus, Alternaria leaf spot and Fusarium seedling blight. Major diseases in radish were virus, white rust, black rot, root rot, leaf spot and Fusarium seedling blight. Disease incidence reached peak on Aug. 20 with $27\%$ infection in radish and with $20\%$ infection in Chinese cabbage during the growing season, and declined thereafter. Percentage of infection in each growth stage showed $25\%$ at root thickening stage and $26\%$ at the harvest time in radish; and the head formation stage, $24\%$ at the harvest time. The data indicate that disease incidence in radish increased rapidly at late growing stage and progressively increased in Chinese cabbage Seedling blight caused by Fusarium sp. and root rot caused by Aphanomyces sp. were also observed in those areas. Cool and wet weather appeared to be favorable for disease incidences during the rainy period of growing season although average temperature was about $25^{\circ}C$. Populations of aphids were lower in the alpine vegetable growing area than that of flat areas. Aphids as virus vectors from total aphids collected were $73.5\%$ or 289 virus vectors /993 total aphids in Namweon and $18.1\%$ or 31 virus vectors/171 total aphids in Muju. The most prerevalent species of aphids was Myzus persicae Sulz.

• Research in Plant Disease
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• v.10 no.3
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• pp.159-166
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• 2004

This study were carried out to identify pathogens and determine the seasonal occurrence and chemical control of safflower (Carthamus tinctorius) diseases from 2000 to 2002 in Gyengbuk province, Korea. Major diseases of safflower were, anthracnose caused by Colletotricum acutatum in open field, and gray mold by Botrytis cinerea in rain sheltered plastic house. Other diseases occurred were powdery mildew caused by Sphaerotheca fuliginea, collar rot by Sclerotium rolfsii, leaf spot by Alternaria carthami and A. alternata, rust by Puccinia carthami, root-rot and stem-rot by Phytophthora cactorum, root-rot and wilt by Fusarium oxysporum and damping-off by Pythium ultimum. Seasonal occurrence of anthracnose on safflower has begun from late April, and increased until harvesting, especially rapid increased after rainfall during stem elongation season that is from May to June. In open fields, maximum incidence of anthracnose was 67 ％ in late July. But in rain-sheltered plastic house, it was very low, about 5％ in July. Gray mold caused by Botrytis cinerea was most important disease in rain-sheltered plastic house cultivation. Maximum incidence of gray mold on floral head was 27.4％, whereas other diseases occurred below 1 ％. In the test of the chemical control of the safflower anthracnose, metiram WP, carbendazim$.$kasugamycin WP and iminoctadintris$.$thiram WP were the highest controlling chemicals. In chemical control of gray mold, iminoctadintris$.$thiram WP, fluazinam WP and iprodion WP showed highest controlling effects.

• Research in Plant Disease
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• v.24 no.2
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• pp.123-131
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• 2018

Kiwifruit has been cultivated in southern coastal regions of Korea since late 1970s. New cultivars have been successively released in recent years. In this study, we investigated major disease and pest incidences in new kiwifruit cultivars 'Goldone', 'Redvita' and 'Garmrok' at open field in Sacheon for 3 years and rain-proof field in Jeju for 2 years. For the bacterial canker, the 3 new cultivars showed more disease occurrence in Sacheon but rare in Jeju. For leaf spot disease, compared to disease incidence of 20% on 'Hayward' in Sacheon, cv. 'Garmrok' had high incidence about 60% but cv. 'Goldone' and cv. 'Redvita' had low incidence less than 20%. However, in Jeju, diseases incidences of all the new cultivars were lesser than 20%. In the case of Hemiptera, many Halyomorpha halys and Nezara antennata appeared in Sacheon but in Jeju Plautia stali was dominated. Isolated bacterial canker pathogen was identified as Pseudomonas syringae pv. actinidiae biovar 3. Leaf spots pathogens were Phomopsis sp., Phoma sp., Fusarium tricinctum and Alternaria alternata. This study shows the disease information on new kiwifruit cultivars and the adequate disease managements will be required.