• Research in Plant Disease
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• v.10 no.4
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• pp.268-271
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• 2004

Occurrence and soil fumigation effect on black root rot of peony was investigated. Peony was severely infected to black root rot caused by Cylindrocarpon destructans in continuous cropping field, but in first cropping field was less infected. To control black root rot, soil improvement, soil fumigation and the root dipping in chemicals were trialed in peony continuous cropping field. Black root rot was not decreased by soil improvement, but incidence of black root rot of peony cultivated in continuous croping field of peony was decreased by soil fumigation with Dazomet GR. and dipping of peony root in chemicals.

• Research in Plant Disease
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• v.15 no.2
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• pp.94-100
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• 2009

These experiments were conducted to improve the effect of seed disinfection on rice seed severely infected Bakanae disease by seed soaking into mixed solution of prochloraz EC and fludioxonil FS. We investigated the effects of various concentrations of two fungicides mixed solution on spore germination and mycelial growth of Fusarium fujikuroi. Mycelial growth was inhibited 100% at $10{\mu}g$/ml of prochloraz and 33.3% at $80{\mu}g$/ml of fludioxonil. Spore germination was inhibited 81.4% at $40{\mu}g$/ml of prochloraz. Interestingly, mixed solution of $5{\mu}g$/ml or $10{\mu}g$/ml of each fungicide inhibitied 100% of mycelial growoth and 99.2% of spore germination, respectively. Severely infected rice seeds soaked into mixed solution composed of $125{\mu}l$/ml of prochloraz and $50{\mu}l$/ml of fludioxonil showed 2.1% of disease symptoms compared to 20.4% of prochloraz $125{\mu}l$/ml, but higher concentrations of prochloraz decreased the seedling stand rate. When the seed soaking time was longer and temperature was higher, control effect on Bakanae disease was improved, but seedling stand was lower about 80% over $35^{\circ}C$.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1999.07a
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• pp.65-70
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• 1999

벼 재배의 생력화를 위하여 현재 국내에는 벼 직파 재배 기술이 확대 보급되고 있다. 기존 벼 직파 재배 기술은 직파유형에 따라 차이가 있지만 발아율 및 입모율, 도복, 잡초방제, 종자손실 및 유동, 포장준비 및 재배관리에 많은 문제점들이 있어 이를 획기적으로 개선할 수 있는 방안이 절실한 실정이다. 벼 펠렛 종자를 이용한 파종은 현행 직파 재배의 여러 문제점들을 해결할 수 있을 뿐만 아니라 입모율 향상, 초기생육촉진 및 초기 병충해 방제, 시비기술의 혁신을 기할 수 있어 안정적 직파 재배 기술을 확립할 수 있을 것으로 보인다. (중략)

• Korean journal of applied entomology
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• v.53 no.4
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• pp.339-346
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• 2014

To control populations of the chestnut weevil, Curculio sikkimensis Heller, the effects of various immersion temperatures and times on the chestnut weevil were tested. The effects of immersion treatments on chestnut fruits were also analyzed. The mortality levels of C. sikkimensis larvae were evaluated at various temperatures ($30^{\circ}C$, $35^{\circ}C$, $40^{\circ}C$, $45^{\circ}C$, and $50^{\circ}C$) and time intervals (1, 2, 3, 5, 7, 10, 15, 22, and 24 h). Changes in the chestnut fruit due to the immersion treatment were measured in terms of color (lightness, redness, and yellowness), physiological effects (germination rate and decay rate), hardness, and change in constituent properties (moisture content, free sugar content, and tannin content). Mortality levels of C. sikkimensis larvae after immersion treatment at $30^{\circ}C$ were over 70% and 100% after 2 h and 7 h, respectively. Color (lightness, redness, and yellowness) of the chestnut fruits was not significantly different at $30^{\circ}C$ and $35^{\circ}C;$ however, the color was affected at temperatures over $40^{\circ}C$. The germination rate of the fruit was not affected by the immersion treatments, but the decay rate at $40^{\circ}C$ increased with an increase in immersion time. The hardness of the fruits decreased with an increase in immersion times and temperatures. These results can be used in the future for developing methods for the control of chestnut weevil populations.

• Korean journal of applied entomology
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• v.62 no.1
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• pp.43-48
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• 2023

The efficacy of spinetoram sprayed from an unmanned helicopter to control two insect vectors of pine wood nematodes, Monochamus alternatus and M. saltuarius was assessed. By using a ULV (Ultra Low Volume) sprayer, the mortality rates of phenthoate, bifenthrin, etofenprox, and diflubenzuron, which are registered for use against coleopteran insects, indoxacarb and spinetoram, which are registered for use against lepidopteran insects, were evaluated for efficacy as aerial spraying agents. The ULV test, using 33- and 55-fold dilutions of phenthoate, bifenthrin, indoxacarb, and spinetoram demonstrated a 100% insect mortality rate upon contact and feeding mortality on the third day after treatment, while etofenprox and diflubenzuron exhibited a slightly lower mortality rate than the remaining compounds. Consequently, spinetoram was selected as a candidate pesticide for aerial spraying and its efficacy to control the insect vectors was assessed. The x 33 dilution of spinetoram resulted in a 98.6-100% control efficacy against two insect vectors. However, risk assessment for bees following aerial spraying will be necessary before applying the pesticide to control insect vectors.

• Applied Biological Chemistry
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• v.44 no.2
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• pp.109-115
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• 2001

The foliar uptake of dimethomoiph induced by several nonionic surfactants was measured in order to study the correlations between the uptake rate of dimethomorph and the fungicidal activity to cucumber downy mildew. Dimethomorph was not absorbed in cucumber leaf in the absence of activator surfactant. And the curative effect of dimethomoiph WP to cucumber downy mildew was very low under the concentration of 250 ${\mu}g/ml$. But dimethomorph uptake was remarkably enhanced by addition of nonionic surfactants, such as polyoxyethylene cetyl ether, polyoxyethylene oleyl ether, and polyoxyethylene stearyl ether. And the curative effect to cucumber downy mildew was enhanced with proportion to uptake rate of dimethomorph. The protective effect to cucumber downy mildew, however, tends to decrease with the increase of foliar uptake of dimethomorph. The uptake rate of dimethomorph to cucumber leaf was proportional to the content of polyoxyethylene cetyl ether in formulation, but was decreased with dilution.

• Korean journal of applied entomology
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• v.51 no.4
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• pp.325-329
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• 2012

In this study, 1, 2 and 4% aqueous extracts of common cocklebur (Xanthium strumarium) fruit were tested against pulse beetle (Callosobruchus chinensis) for development of an environmental friendly control methods of this pest. The common cocklebur fruit extracts showed effects on mortality, repellency, fecundity and adult emergence of C. chinensis and inhibited pulse grains from damage. The 4% extract showed the highest mortality (26%) and repellency rate (53.3%) at 2 day after treatment and 3 hours after treatment, respectively. The studied insects revealed lowest fecundity (113.7 female-1), highest percentage of adult emergence inhibition (37.0%) and lowest percentage (42.3%) of seed damage when they were reared on pulse grains mixed with 4% extract. This finding indicated that common cocklebur fruit extract may be used in the integrated management of pulse beetle for protecting stored grains.

• Korean Journal of Weed Science
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• v.2 no.2
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• pp.146-151
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• 1982

Herbicide mixtures, butachlor + naproanilide, CG113 + naproanilide and benthiocarb + naproanilide were tested in order to control Sagittaria pygmaea Miq., one of the most serious perennial weeds in paddy field of Honam area. 92% of tuber of Sagittaria pygmaea Miq. was distributed within 9cm from the soil surface and number of emerged Sagittaria pygmaea Miq. increased until 40 days after rice transplanting but decreased thereafter. Number and dry weight of survived Sagittaria pygmaea Miq. were much less in butachlor + naproanilide, CG 113 + naproanilide and benthiocarb + naproanilide treatments than perfluidone and it was controlled by up to 95% by mixture treatments. Number of rhizome of Sagittaria pygmaea Miq. was decreased by all herbicide treatments and especially mixture treatment significantly reduced rhizome formation compared to perfluidone and 2.4 -D treatments. CG113 + naproanilide treatment caused phytotoxicity that tip of leaf sticked to leaf sheath curvedly in Indica ${\times}$ Japonica rice, Iri 358, but it was recovered within 10 days after herbicide treatment.

• Journal of Life Science
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• v.14 no.5
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• pp.761-769
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• 2004

This study was investigated the occurrence of sclerotinia rot caused by Sclerotinia sclerotiorum at the major perilla cultivating area, Gangdong-dong, Gangseo-gu, Busan in 1998. The incidence of this disease ranged from 8.1 to 28.3% at Gangdong-dong area during the growing seasons. Symptoms of the disease initially appeared damping-off of infected stems and soft-rot on the leaves of perilla. Under the relatively high humidity, abundant white mycelia of the pathogen formed on the lesion developed into black sclerotia later and the infected leaves were finally fell down. Sixteen isolates, Sl-S16, isolated from diseased lesions showing typical symptoms, and pathogenicity was tested using mycerlial disks. Among them, S2 isolate showing the most strong pathogenicity was selected and identified as Sclerotinia sclerotiorum on the basis of morphological and cultural characteristics. For biological control, an antagonistic bacteria, N4 isolate which effectively inhibited not only mycelial growth of S2 isolate but also suppress sclerotinia rot on the pot assay, was selected and identified as Bacillus megaterium according to Bergey's manual and API system., Wettable powder type, N4 formulation using B. megaterium N4 isolate was developed and estimated its control effect on perilla crops in a plastic house. As a results, N4 formulation which applied before 3 days inoculation of pathogen was effectually controlled Sclerotinia rot as the control value of 98.0%, was more effective than chemical fungicide, benomyl showing the control value of 78.0%. This is the first report of wettable powder formulation as a biocontrol agent using B. megaterium N4 against Sclerotinia rot caused by S. sclerotiorum on perilla.

• Korean Journal of Weed Science
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• v.18 no.2
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• pp.106-115
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• 1998

This study was conducted to investigate the effect of oxadiazon, molinate, thiobencarb before seeding on control of red rice and barnyardgrass in water-seeded rice. High application rate plot among oxadiazon treatment plots could observe phytotoxicity symptoms depending on field conditions, but these injury recovered gradually with time. Molinate and thiobencarb application plots at the concentration of 225~400, 210~420g ai/l0a respectively were not observed phytotoxicity. Control of red rice was different according to kinds of herbicides and application rates. Oxadiazon showed higher control performance at the concentration of more than 60g ai/10a. Control effect of molinate and thiobencarb against red rice was enhanced with the increase of application rate, and both herbicides showed satisfactory effect at more than 300g ai/10a. Control of barnyardgrass showed up to 90~100% in all tested herbicides. There was no significant yield reduction by oxadiazon, molinate, and thiobencarb application before seeding in all tested field. In the pot experiment, crop injury, seedling stand, and early growth were more advantageous at time of drainge after one day after seeding than flooding until rooting.