• The Korean Journal of Pesticide Science
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• v.5 no.2
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• pp.62-66
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• 2001

The thirteen commercial insecticides to Lycoriella mali were investigated on their insecticidal activities and mycelial growth of two Letinula edodes strains. For the adults, insecticides showing over 95% insecticidal activity were chlorpyrifos-methyl, fenthion, fenitrothion, benfuracarb, furathiocarb and deltamethrin. For tile larvae, diflubenzuron and cyromazine showed over 90% insecticidal activity. Fenthion, benfuracarb, furathiocarb, deltamethrin, diflubenzuron and cyromazine did not affect the mycelial growth of L. edodes strain, in Imhyup 1 variety. And deltamethrin, diflubenzuron and cyromazine did not affect that in Sanlim-5. Insecticides showing over 80% residual effect for 14 days were benfuracarb to the adults and diflubenzuron and cyromazine to the larvae. Control effect of furathiocarb, fenthion, benfuracarb, deltamethrin, diflubenzuron and cyromazine against larvae of Lycoriella mali showed 90% ten days after application under sawdust cultivation. Among them, benfuracarb, fenthion and furathiocarb revealed excellent control effect against adults. These results indicate that benfuracarb, fenthion, and furathiocarb can be used for the control of Lycoriella mali in the field. However, further studies are needed on the effect of insecticides treatment oil fruit-body yield and chemical residue in the mushroom tissues.

• Journal of Sericultural and Entomological Science
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• v.34 no.2
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• pp.1-5
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• 1992

Crude fermentation broths of two bacterial isolates, S-11 and S-25, from about 200 soil samples, showed inhibitory activities against the crude chitinase prepared from alimentary canals of the silkworm, Bombyx mori, as well as against reagent chitinase from Streptomyces griseus, in vitro. The chitinase inhibitors also exhibited insecticidal activities by preventing larval-pupal ecdysis when these broths were injected into the silkworm larvae during spinning.

• Korean journal of applied entomology
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• v.43 no.4 s.137
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• pp.317-322
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• 2004

Insecticidal activity, systemic and residual effects, and effects on enzyme activities (esterase, acetylcholinesterase, glutathione S-transferase) of indoxcarb were evaluated against Plutella xylostella. The insecticide was very effective against larvae of P. xylostella. Also, indoxacarb showed only residual effect to P. xylostella when applied to vegetable leaves. It inhibited acetylcholinesterase activity, but didn't do esterase and glutathione S-transferase activities.

• Korean journal of applied entomology
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• v.52 no.1
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• pp.69-69
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• 2013

• Korean Journal of Plant Tissue Culture
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• v.25 no.2
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• pp.95-98
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• 1998

Hypocotyl explants of flowering cabbage were cocultured with Agrobacterium tumefaciens LBA4404;;pGA875 harboring proteinase inhibitor II(PI-II) cDNA and then regenerated into plants. Sucessful transcripts of PI-II gene were detected by RNA dot blot analysis. Bioassay was conducted on transgenic flowering cabbage. It was confirmed that insecticidal activities of transformants were much higer than that of control plants. In progeny test of hansformants, 27.4% of T$_1$ seeds was resistant on MS medium containing 20 mg/L kanamycin.

• The Korean Journal of Mycology
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• v.46 no.4
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• pp.479-490
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• 2018

Red pepper is seriously damaged by thrips (Thrips palmi) and anthracnose caused by Colletotrichum acutatum throughout its development. Because of biotic constraints, producers often depend on chemicals that are expensive and have adverse effects on the environment, operator, and beneficial insects. In addition, resistance is developed because of the repeated use of chemicals. In recent decades, the use of microorganisms in crop protection has become a credible alternative because it is eco-friendly. In this study, we aimed to select isolates with insecticidal and fungicidal activities against the pathogens that cause anthracnose and thrips. We treated T. palmi adults and juveniles with 13 strains of entomopathogenic fungi (isolated from the soil by using the insect-bait method), and 6 strains showed excellent insecticidal activity (70-100%) 5 days after the treatment. The selected isolates were cultured with C. acutatum to screen for the strain with excellent anti-fungal activities, among which an isolate FT333 showed more than 95% control efficacy against C. acutatum in vitro. The isolate was identified as Isaria javanica through its morphological characteristics and phylogenetic analysis of the ITS and ${\beta}-tubulin$ nucleotide sequences. The Isaria javanica FT333 isolate could be used effectively for dual bio-control of thrips and anthracnose during red pepper cultivation.

• The Korean Journal of Pesticide Science
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• v.3 no.3
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• pp.60-67
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• 1999

Insecticidal activities of imidacloprid to sucking type insect pests, brown planthopper (BPH, Nilaparvata lugens) and peen peach aphid (GPA Myzus persicae), to chewing type insect pests, tobacco cut worm (TCW; Spodoptera litura) and beet armyworm (BAW, Spodoptera exigua) and to spiders, Pirata subpiraticus, Pachygnata clercki and Ummeliata insecticeps, as natural enemies were investigated by several bioassay methods. $LD_{50}$ of the chemical by topical treatment to BPH was 0.015 ${\mu}g/g$(48 hrs), while $LC_{50}s$ by leaf dipping and root zone treatment were 18.1 and 21.5 ppm, respectively. There was no difference in insecticidal activities between leaf dipping and root zone treatment. Imidacloprid also showed ovicidal effect of root zone treatment and its $LC_{50}$ was 6.8ppm $LD_{50}$ (48 hrs after treatment) of imidacloprid to GPA was $0.4{\mu}g/g$ in case of topical application and $LC_{50}s$ by leaf dipping and root zone treatment were 1.9 ppm and 13.7 ppm respectively. Leaf dipping was more effective than root zone treatment in GPA At topical application $LD_{50}$ (48 hrs after treatment) of imidacloprid to chewing type insect pests, TCW and BAW, were greater than 1,492 and $312{\mu}g/g$ and $LC_{50}s$ by leaf dipping method were 4,803 and Heater than 5,000ppm respectively. This means that imidacloprid has much less effect on chewing type insect pests, TCW and BAW. $LD_{50}$(48 hrs after treatment) of imidacloprid to wandering spiders, Pirata subpiraticus, Pachygnata clercki at topical application were greater dan $2941{\mu}g/g$ and greater than $2,976{\mu}g/g$ respectively and that to webbing spider, Ummeliata insecticeps, was 357 ${\mu}g/g$. Imidacloprid showed very low toxicity to the spiders and its selective toxicity ratios between spiders and BPH were greater than 19,600, greater than 19,800 and 23,800, respectively.

• Korean Journal of Weed Science
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• v.32 no.2
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• pp.98-106
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• 2012

This research has been carried out to find out the highest effect on insecticidal, fungicidal and herbicidal activities in leaves, stem and tuber extracts of yacon (Smallanthus sonchifolius) and extraction methods such as water, boiling water and methanol. Characteristics of potential herbicidal components among extraction methods were investigated by solvent fractions such as hexane, chloroform, ethyl acetate, butanol, and water. Generally, methanol extract was the best on inhibition of germination rate, plant height, and root length in cucumber and barley. On the other hand, the inhibition effect on growth in cucumber and barley was the best in tuber among plant parts of yacon. Inhibition of germination rate, plant height, and root length in cucumber and barley in solvent fractions was the best in water fraction, but there were no differences in other fractions. Digitaria sanguinalis L. and Solanum nigrum L. by 5 and 10% extractions of yacon tuber were controlled by more than 70~80% and 95~100%, respectively. However, there was no inhibition effect on foliar treatment in cucumber and barley as affected by 5 and 10% extractions of yacon tuber. Mortality of green peach aphid (Myzus persicae Sulzer) was 50% at 3 days after treatment of 5% extracts of yacon leaves. Mortality of brown plant hopper (Nilaparvata lugens Stal) was only 24% in 5% extracts of stems and leaves with midrib, but was 57% in 5% extracts of leaves without midrib. There was no fungicidal effect on anthracnose (Colletotrichum truncatum), wilt disease (Fusarium oxysporum), verticillium wilt (Verticillium dahliae), bacterial blight (Xanthomonus oryzae) in 5% extracts of yacon leaves.

• Journal of Microbiology and Biotechnology
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• v.18 no.3
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• pp.397-403
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• 2008

Nikkomycins are a group of peptidyl nucleoside antibiotics with potent fungicidal, insecticidal, and acaricidal activities. sanN was cloned from the partial genomic library of Streptomyces ansochromogenes 7100. Gene disruption and complementation analysis demonstrated that sanN is essential for nikkomycin biosynthesis in S. ansochromogenes. Primer extension assay indicated that sanN is transcribed from two promoters (sanN-P1 and sanN-P2), and sanN-P2 plays a more important role in nikkomycin biosynthesis. Purified recombinant SanN acts as a dehydrogenase to convert benzoate-CoA to benzaldehyde in a random-order mechanism in vitro, with respective $K_{cat}/K_m$$ values of $3.8mM^{-1}s^{-1}\;and\;12.0mM^{-1}s^{-1}$ toward benzoate-CoA and NADH, suggesting that SanN catalyzes the formation of picolinaldehyde during biosynthesis of nikkomycin X and Z components in the wild-type stain. These data would facilitate us to understand the biosynthetic pathway of nikkomycins and to consider the combinatorial synthesis of novel antibiotic derivatives.

• Biomolecules & Therapeutics
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• v.15 no.3
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• pp.199-204
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• 2007

Carbamates have excellent insecticidal activities against a broad spectrum of insects. They possess knocking-down, fast-killing, and systemic effects, however, they are toxic to mammals. In this study, we have carried out in vitro genetic toxicity test of methylcarbamate and microarray analysis of differentially expressed genes in response to methylcarbamate. Methylcarbamate did not show mutations in base substitution strain TA1535 both with and without exogenous metabolic activation. Methylcarbamate did not show mutations in frame shift TA98 both with and without exogenous metabolic activation. Methylcarbamate showed DNA damage based on single cell gel/comet assay in L5178Y cells both with and without exogenous metabolic activation. Methylcarbamate did not increase micronuclei in CHO cells both with and without exogenous metabolic activation. Microarray analysis of gene expression profiles in L5178Y cells in response to methylcarbamate selected differentially expressed 132 genes that could be candidate biomarkers of genetic toxic action of methylcarbamate.