• Mycobiology
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• v.31 no.2
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• pp.113-118
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• 2003

Solanaceous crops grown in greenhouses and fields in Korea were surveyed from 1994 to 2000. Sclerotinia rot most severely occurred up to 60% in potato. Incidence of the disease was as high as 20% at its maximum in tomato and 5% in eggplant, but as low as less than 1% in red pepper. Symptoms of Sclerotinia rot commonly developed on stems of the solanaceous crops but rarely on fruits of eggplant and tomato. A total of 169 isolates of Sclerotinia species was obtained from the diseased solanaceous crops. Out of the isolates, 165 isolates were identified as S. sclerotiorum, and the others as S. minor based on their morphological and cultural characteristics. S. sclerotiorum was isolated from all the solanaceous crops, while S. minor was only isolated from tomato. Eight isolates of S. sclerotiorum and two isolates of S. minor were tested for their pathogenicity to the solanaceous crops by artificial inoculation. All the isolates of the two Sclerotinia spp. induced rot symptoms on stems of the solanaceous crops tested, which were similar to those observed in the fields. The pathogenicity tests revealed that there was no significant difference in the susceptibility of the solanaceous crops to the isolates of S. sclerotiorum. However, in case of S. minor, the potato cultivar Sumi was relatively less susceptible to the pathogen.

• The Korean Journal of Pesticide Science
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• v.18 no.4
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• pp.364-375
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• 2014

This study was carried out to investigate the pesticide efficacy and crop safety among different leafy vegetables applied with foliar spraying under greenhouse and to check extrapolating from some trial data to other minor crops. Leafy vegetables used in this study were: lettuce (Lactuca sativar), leaf broccoli (Brassica oleracea.), chicory (Cichorium intybus.), chinese cabbage (Brassica campestris subsp. napus var. pekinensis), radish (Raphanus sativus), rape (Brassica napus), crown daisy (Chrysanthemum coronarium), edible burdock (Arctium lappa), endive (Cichorium endivia) and mustard greens (Brassica jumcea). Based on the result of control efficacy, all crops were classified into the groups. The results showed the probabilities of extrapolating the control value data of minor crop within the same group. It would be possible to use the pesticides which are already been registered for similar crops to those crops have no registered pesticides.

• The Korean Journal of Pesticide Science
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• v.13 no.1
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• pp.28-38
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• 2009

An extrapolation of residue data of seven commonly used pesticides namely bifenthrin, chlorothalonil, cypermethrin, diazinon, fenvalerate, phenthoate and procymidone on a total of 22 minor crops has been carried out in an experimental field trial. The pesticides were applied to 11 leafy-, 5 root- and 6 stem-crops grown in the experimental green-house and the crops and plants were randomly collected at 1, 3, 5, 7 days after application. The average recoveries of applied pesticides were ranged from 72.0 to 117.0% in leafy crops, from 81.3 to 105.0% in stem crops and from 70.1 to 108.1% in the root-crops. Limits of detection (LODs) were 0.005-0.1 mg/kg in the leafy crops and 0.001-0.005 mg/kg in both the stem & root crops. Based on the results of residual dissipation pattern and their morphology, all crops were classified into high and low residual groups. The results showed that it might be possible to extrapolate residual data of stem-crops to root-crops within the same group. Crops that have currently no registered pesticide for use, would be possible to use the pesticides which are already been registered for the similar crops.

• The Plant Pathology Journal
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• v.19 no.1
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• pp.69-74
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• 2003

Cruciferous crops grown in greenhouses and fields in Korea were surveyed from 1995 to 2000. Sclerotinia rot most severely occurred up to 30％ in cabbage. Incidence of the disease was as high as 20% at its maximum in Chinese cabbage and rape and 10％ in radish, but as low as less than 1 or 2％ in broccoli and kale. Symptoms of Sclerotinia rot commonly developed on loaves and stems of the crucifers, but rarely on rachises of broccoli. A total of 112 isolates of sclerotinia species was obtained from the diseased crucifers. Out of the isolates, 103 isolates were identified as S. sclerotiorum, and the rest as 5. minor based on their morphological and cultural characteristics. S. sclerotiorum was isolated from all the crucifers, while S. minor was isolated from Chinese cabbage, broccoli, and kale. Six isolates of S. sclerotiorum and three isolates of S. minor were tested for their pathogenicity to the crucifers by artificial inoculation. All the isolates of the two Sclerotinia spp. induced rot symptoms on the plants of the crucifers tested, which were similar to those observed in the fields. The pathogenicity tests revealed that there was no significant difference in the susceptibility of the crucifers to the isolates of S. sclerotiorum. However, in case of S. minor, radish was relatively less susceptible to the pathogen.

• Korean Journal of Weed Science
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• v.30 no.3
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• pp.243-251
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• 2010

The study was conducted to evaluate the weed suppressing effects of two winter cover crops, Chinese milk vetch (CMV) and rye, in minor cereal fields in 2009. The suppressing activities of cover crops were due to the allelopathy of cover crops during weed emerging periods and competitive activity during vegetative growth of weeds. Weed suppression by cover crops were changed from 26.5 g $m^{-2}$, 0.1 g $m^{-2}$ and 0.2 g $m^{-2}$ in control, rye field and CMV field, respectively, on June 22 to 428.6 g $m^{-2}$, 1 g $m^{-2}$ and 403.9 g $m^{-2}$ in control, rye field and CMV field, respectively, on July 22. The weed dry weights were further changed to 656.3 g $m^{-2}$, 607.8 g $m^{-2}$ and 511.8 g $m^{-2}$ in control, rye field and CMV field, respectively, on August 22. The suppressing effect of cover crops also observed in minor cereals. Plant height and dry weight of sorghum was reduced to 68.7% and 33.6% of handweeding, respectively, on August 5. The reduction was recovered to 82.7% and 55.6% of control, respectively, on August 26. In addition, heading date of minor cereals was delayed by 7 days with rye.

• Korean Journal of Weed Science
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• v.10 no.2
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• pp.153-158
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• 1990

• Mycobiology
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• v.30 no.1
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• pp.41-46
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• 2002

Composite vegetable crops grown in greenhouses and open fields in Korea were surveyed from 1995 to 1999. Occurrence of Sclerotinia rot was observed in 123 of 277 lettuce fields, in 11 of 18 head lettuce fields, in 12 of 14 endive fields, and in 4 of 38 garland chrysanthemum fields surveyed during the growing seasons. The disease most severely occurred up to 80% on lettuce. Incidence of the disease was as high as 20% at its maximum on endive and garland chrysanthemum but relatively low on head lettuce. Symptoms of the disease developed on leaves of all the composites, crowns of lettuce and head lettuce, and stems of garland chrysanthemum. Out of 240 isolates of Sclerotinia species obtained from the diseased composites, 169 isolates were identified as Sclerotinia sclerotiorum, and the others as S. minor based on their morphological and cultural characteristics. S. sclerotiorum was isolated from all the composites, and S. minor only from lettuce and endive. Eight isolates of S. sclerotiorum and four isolates of S. minor were tested for their pathogenicity to the composites by artificial inoculation. All the isolates of the two Sclerotinia spp. induced rot symptoms on the plants of the composites by artificial inoculation, which were similar to those observed in the fields. The pathogenicity tests revealed that there is no significant difference in virulence of the isolates to the composites and in susceptibility of the composites to the isolates.

• Korean Journal of Environmental Agriculture
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• v.41 no.1
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• pp.55-64
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• 2022

BACKGROUND: This study was conducted to evaluate the residual characteristics and safety assessment of αcypermethrin and deltamethrin in minor crops, chives and spring onion cultivated in greenhouse. METHODS AND RESULTS: The insecticides α-cypermethrin 2% EC and deltamethrin 1% EC used in the experiment were diluted 1,000 times and then sprayed on chives and spring onion twice with 1-week intervals at 0, 7, 14, and 21 days before harvest. The residual insecticides were extracted from the minor crops using QuEchERS method and analyzed by GC-MS/MS. The average initial residues of α-cypermethrin and deltamethrin in chives after 21 days decreased from 2.74 to 0.82 mg/kg and 1.12 to 0.16 mg/kg, respectively. Similarly, in spring onion the residues after the same periods decreased from 0.26 to <0.01 mg/kg for α-cypermethrin and from 0.07 to <0.01 mg/kg for deltamethrin. CONCLUSION(S): The PHIs (pre-harvest intervals) for α-cypermethrin and deltamethrin in chives are recommended as 14 days before harvest with twice applications of the pesticides, whereas for α-cypermethrin in spring onion PHI of 7 days before harvest is recommended with 3 times of applications and PHI of 21 days for deltamethrin. The theoretical maximum daily intakes of cypermethrin and deltamethrin were 68.8% and 64.2%, respectively, indicating that residues of both compounds did not pose considerable health risks to consumers.

• Weed & Turfgrass Science
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• v.7 no.1
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• pp.72-75
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• 2018

Balloon flower (Platycodon grandiflorum) is one of minor crops in Korea. Only four ACCase inhibiting herbicides are registered for P. grandiflorum and the farmers usually use general but unregistered herbicides which can cause critical phytotoxicity. So, this study was conducted to investigate effects of alachlor and pendimethalin on germination and early growth of P. grandiflorum. To evaluate the effect of alachlor and pendimethalin, two herbicides were treated to the seeds in petri-dish and soil. In the petri-dish, alachlor completely inhibited the germination as well as pendimethalin inhibited the germination slightly but not significantly. In case of soil application, alachlor inhibited germination and plant height of P. grandiflorum significantly as well as pendimethalin inhibited plant height and root length significantly. We showed the possibility of phytotoxicity of alachlor and pendimethalin to P. grandiflorum and strongly suggest that two herbicides should not be used to the cultivation of P. grandiflorum. Unregistered herbicides should not be used for weed management and additional researches for screening of safe herbicide to minor crops should be conducted as soon as possible.

• Asian Journal of Business Environment
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• v.14 no.3
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• pp.37-50
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• 2024

The agricultural policy of Kim Jong-un's regime inherits the economic reform policy of the Kim Jong-Il period, which expands the autonomy of production and allows the market to dispose of products. The formation of markets represents an important factor in the business environment, as it indicates the establishment of fundamental conditions for management. However, major crops are still mainly managed by the state, and the government implements agricultural policies, such as emphasizing "Juche Farming." This study analyzed the impact of transition economic policies during the Kim Jong-un period on agricultural production using variability. Production variabilities increased for minor grain crops compared to previous years, but those of major grain (rice and maize) and horticultural crops did not change significantly. Even the production quantity of horticultural crops decreased, which is different from previous predicts that the expansion of the North Korean market would increase the consumption power of North Koreans and promote horticultural crop production. This study underscores the imperative for North Korea to develop policies aimed at stabilizing crop yields in the face of production variability. It proposes the establishment of an agricultural early warning system as a feasible solution to enhance agricultural infrastructure and promote inter-Korean cooperation.