• Horticultural Science & Technology
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• v.19 no.4
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• pp.591-595
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• 2001

This study was conducted to find out the proper chemicals and doses for controlling the bulb disease of Lilium Oriental hybrids 'Capablanca' and 'Marco Polo' cultivars during storage, and to ascertain any disadvantage of the treatment on shoot growth and flower development. Bulbs of 'Casablanca' and 'Marco Polo' cultivars were dipped in some fungicide solutions, including azoxystrobin, benomyl+thiram, and prochloraz, and culture broth of antagonistic bacteria for one hour. The rot was apparently inhibited by azoxystrobin and prochloraz solution dippings and it was not by benomyl+thiram in bulbs produced domestically. To improve physiological integrity, calcium chloride was treated. However, this treatment had no positive effects on bulb rot of lily. When bulbs were dipped in one-fifth of diluted broth. But the bulb rot was inhibited effectively as compared with untreated during storage. Benomyl+thiram and that with calcium inhibited the sprouting in 'Casablanca' and 'Marco Polo' cultivars during cultivation. Calcium and benomyl+thiram treatments decreased growth of leaf and flower but with no statistically significant difference. Other fungicidal materials treated to bulbs showed no effect on vegetative growth and flower quality.

• Journal of the Korean Chemical Society
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• v.55 no.3
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• pp.436-443
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• 2011

The solid complexes of La(III), Ce(III), Pr(III), Nd(III), Sm(III) and Gd(III) with 4-hydroxy-3-(1-{2-(2,4-dihydroxy-benzylidene)-amino phenylimino}-ethyl)-6-methyl-pyran-2-one ($H_2$L) derived from o-phenylenediamine, 3-acetyl-6-methyl-(2H)pyran,2,4(3H)-dione (dehydroacetic acid or DHA) and 2, 4-dihydroxy benzaldehyde have been synthesized and characterized by elemental analysis, conductometry, magnetic susceptibility, UV-visible, FT-IR, $^1H$-NMR, X-ray diffraction, thermal analysis study, and screened for antimicrobial activity. The FT-IR spectral data suggest that the ligand behaves as a dibasic tetradentate ligand with ONNO donor atoms sequence towards central metal ion. From the microanalytical data, the stoichiometry of the complexes has been found to be 1:1 (metal: ligand). The physico-chemical data suggests distorted octahedral geometry for La(III), Ce(III), Pr(III), Nd(III), Sm(III) and Gd(III) complexes. The X-ray diffraction data suggests monoclinic crystal system for La(III) and Ce(III) and orthorombic crystal system for Pr(III) and Nd(III) complexes. Thermal behavior (TG/DTA) of the complexes was studied and kinetic parameters were determined by Horowitz-Metzger and Coats-Redfern methods. The ligand and its metal complexes were screened for antibacterial activity against Staphylococcus aureus, Escherichia coli, Bacillus Sp. and fungicidal activity against Aspergillus Niger, Trichoderma and Fusarium oxysporum.

• Journal of the Korean Chemical Society
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• v.53 no.4
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• pp.407-414
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• 2009

The solid complexes of Cu(II), Ni(II), Co(II), Mn(II) and Fe(III) with 4-hydroxy-3-(1-{2-(2-hydroxybenzylidene)- amino phenylimino}-ethyl)-6-methy-pyran-2-one (H2L) derived from o-phenylenediamine, 3-acetyl- 6-methyl-(2H) pyran, 2,4 (3H)-dione (dehydroacetic acid or DHA) and salicylic aldehyde have been synthesized and characterized by elemental analysis, conductometry, magnetic susceptibility, UV-visible, IR, $^1H$-NMR spectra, X-ray diffraction, thermal analysis, and screened for antimicrobial activity. The IR spectral data suggest that the ligand behaves as a dibasic tetradentate ligand with ONNO donor atoms sequence towards central metal ion. From the microanalytical data, the stoichiometry of the complexes has been found to be 1:1 (metal: ligand). The physico-chemical data suggests square planar geometry for Cu(II) and Ni(II) complexes and octahedral geometry for Co(II), Mn(II) and Fe(III) complexes. The x-ray differaction data suggests orthorhombic crystal system for Cu(II) complex, monoclinic crystal system for Ni(II), Co(II) and Fe(III) and tetragonal crystal system for Mn(II) complex. Thermal behaviour (TG/DTA) of the complexes was studied and kinetic parameters were determined by Coats-Redfern method. The ligand and their metal complexes were screened for antibacterial activity against Staphylococcus aureus and Escherichia coli and fungicidal activity against Aspergillus Niger and Trichoderma.

• Korean Journal of Microbiology
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• v.49 no.1
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• pp.17-23
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• 2013

Candida biofilms are organized microbial communities growing on the surfaces of host tissues or indwelling medical devices, and the biofilms show enhanced resistance against the conventional antifungal agents. The roots of Coptidis chinensis have been widely used for medicinal purposes in East Asia. The present study was aimed to assess the effect of C. chinensis aqueous extract upon preformed biofilms of 10 clinical Candida albicans isolates and the antifungal activities which contribute to inhibit the C. albicans biofilm formation. Its effect on preformed biofilms was judged using XTT [2,3-Bis-(2-Methoxy-4-Nitro-5-Sulfophenyl)-2H-Tetrazolium-5-Carboxanilide)] reduction assay, and metabolic activity of all tested strains was reduced significantly ($57.3{\pm}14.7%$) at $98{\mu}g/ml$ of the C. chinensis extract. The extract damaged the cell membrane of C. albicans which was analyzed by fluorescein diacetate and propidium iodide staining. The anticandidal activity was fungicidal, and the extract obstructed the adhesion of C. albicans biofilms to polystyrene surfaces, arrested C. albicans cells at $G_o/G_1$ as well, and reduced the growth of biofilms or budding yeasts finally. The data suggest that C. chinensis has multiple antifungal effects on target fungi resulting in preventing the formation of biofilms. Therefore, C. chinensis holds great promise for exploring antifungal agents from natural products in treating and eliminating biofilm-associated Candida infection.

• Applied Biological Chemistry
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• v.44 no.3
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• pp.191-196
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• 2001

${\alpha},{\beta}$-Unsaturated carboxanilides 5 with trifluromethylated dihydro-1,4-oxathiins were synthesized for the development of new agrochemical fungicide. Chlorination of trifluoromethylated ${\beta}-keto$ ester 6 followed by the reaction with 1,2-mercaptoethanol gave intermediate 1,4-oxathiane 11. Without purification of 11, substitution of hydroxy group by chlorine, followed by dehydrochlorination of 10 in the presence of triethylamine afforded trifluoromethylated dihydro-1,4-oxathiin ethyl ester 9. Acylation of the hydroxy group of the carboxylic acid 12 followed by treatment of various amines gave the corresponding trifluoromethylated dihydro-1,4-oxathiin carboxamides 5. Antifungal screening (in vivo) of the synthesized compounds against typical plant diseases, which include rice blast, rice sheath blight, cucumber gray mold, tomato late blight, wheat leaf rust, and barley powdery mildew, was carried out. Where meta position of the phenyl group was substituted with isopropoxy or isopropyl group, excellent antifungal activities against rice sheath blight and wheat leaf rust were detected.

• The Korean Journal of Pesticide Science
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• v.4 no.1
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• pp.32-37
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• 2000

A series of transition metal complexes of 3,6-bis(6'-methyl-2'-pyridyl)pyridazine ($L^{1}$) and 3,6-bis(2'-pyridyl)pyridazine ($L^{2}$) as artificial nuclease, $1{\sim}8$ were synthesized. After determining of X-ray crystal structure, hydrolysis rate constants of phosphates, as DNA model compound and biological activities were confirmed. $L^{2}$-Zn(II) complex, 8 was shown the best hydrolysis rate constant. The $L^{2}$-Ni(II) complex, 5 and $L^{2}$-Co(II) complex, 6 showed the highest herbicidal activity against SCP (Scriptus Juncoids) with excellent tolerance to rice, ORY (Oryzae sativa L.). And the $L^{1}$-Co(II) complex, 2, $L^{1}$-Zn(II) complex, 4 and ligand ($L^{1}$ amp; $L^{2}$) displayed above 90% fungicidal activity against MAG (Magnaporthe grisea).

• Applied Biological Chemistry
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• v.36 no.4
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• pp.265-270
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• 1993

In order to retain the freshness of fruits and vegetables and to reduce the rate of disease damage, grafruit seed extract (GPSE), natural microorganism control agent, was applied during the preservation process of fresh fruits and vegetables. GFSE showed an effective inhibitory action against plant putrefactive bacteria and fungi which were involved in the decay of fruits and vegetables. Minimal inhibitory concentrations for GFSE against the microbes were in the range of 50 to 2,000 ppm. Direct observation of microbial cells and spores using electron microscopy showed their function was destroyed by the treatment of the dilute solutions of GFSE. Fresh Welsh onions, onions and red peppers treated with GFSE and stored in polyethylene film (0.1 mm) retained better quality in color and texture than the non-treated control. GFSE was efficient in controlling the germination of potatoes. It was observed that GFSE would reduce disease damages and have bactericidal and fungicidal properties during the storage of such fruits and vegetables as zucchinis, cucumbers, tomatoes and mandarin oranges.

• The Korean Journal of Pesticide Science
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• v.12 no.1
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• pp.88-96
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• 2008

To obtain protoplasts of Colletotrichum acutatum JC24, conidia were inoculated onto cellophane membrane placed on PDA and incubated at $25^{\circ}C$ for 20 hrs under the dark condition. Cellophane membranes, where mycelia were incubated, were soaked into 2% lysing enzyme solution prepared with 0.02 M phosphate buffer (pH 7.0) including 1.2 M sorbitiol. After treatment in 2% enzyme solution for 2 - 3 hrs, it could be possible to harvest $2-3\;{\times}\;10^6$ protoplasts/mL. The effect of several fungicides on reversion ratio was determined by using the protoplasts obtained from C. acutatum JC24. Any protoplasts could not be reversed to mycelia on reversion PDA amended with $10\;{\mu}\;g\;mL^{-1}$ of propineb. With tebuconazole, inhibition ratio of protoplast reversion was 100 and 0.9% at 0.5 and $0.1\;{\mu}\;g\;mL^{-1}$, respectively, while inhibitory effect on mycelial growth was 85.1 and 75.7%. The inhibitory tendency of carbendazim on protoplast reversion was as same as mycelial growth. In the case of strobilurins, trifloxystrobin and kresoxim-methyl, they only could inhibit protoplast reversion of C. acutatum JC24, when salicylhydroxamic acid (SHAM) was amended into reversion PDA with strobilurins.

• The Plant Pathology Journal
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• v.36 no.4
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• pp.335-345
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• 2020

Tomato grey mould has been one of the destructive fungal diseases during tomato production. Ten mM of menadione sodium bisulfite (MSB) was applied to tomato plants for eco-friendly control of the grey mould. MSB-reduced tomato grey mould in the 3rd true leaves was prolonged at least 7 days prior to the fungal inoculation of two inoculum densities (2 × 10⁴ and 2 × 10⁵ conidia/ml) of Botrytis cinerea. Protection efficacy was significantly higher in the leaves inoculated with the lower disease pressure of conidial suspension compared to the higher one. MSB-pretreatment was not effective to arrest oxalic acid-triggered necrosis on tomato leaves. Plant cell death and hydrogen peroxide accumulation were restricted in necrotic lesions of the B. cinereainoculated leaves by the MSB-pretreatment. Decreased conidia number and germ-tube elongation of B. cinerea were found at 10 h, and mycelial growth was also impeded at 24 h on the MSB-pretreated leaves. MSB-mediated disease suppressions were found in cotyledons and different positions (1st to 5th) of true leaves inoculated with the lower conidial suspension, but only 1st to 3rd true leaves showed decreases in lesion sizes by the higher inoculum density. Increasing MSB-pretreatment times more efficiently decreased the lesion size by the higher disease pressure. MSB led to inducible expressions of defence-related genes SlPR1a, SlPR1b, SlPIN2, SlACO1, SlChi3, and SlChi9 in tomato leaves prior to B. cinerea infection. These results suggest that MSB pretreatment can be a promising alternative to chemical fungicides for environment-friendly management of tomato grey mould.

• Research in Plant Disease
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• v.24 no.1
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• pp.33-40
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• 2018

This study was conducted to evaluate the antifungal activity of 19 agro-materials that have been registered for organic cultivation in Korea, after inoculation of pear leaves with Venturia nashicola and Gymnosporangium asiaticum. In V. nashicola, most of the nine agro- materials containing sulfur and copper completely inhibited spore germination, and some of the spores that germinated did not form appressoria. However, in only lime sulfur, Neobordeaux (cupric sulfate), and Wheengaris (sulfur)showed antifungal activity against G. asiaticum. Among the agro-materials containing plant extracts, Wheengarujaba (wood vinegar+spirits+rhubarb) inhibited conidial germination in V. nashicola and G. asiaticum by 100% and 71.6%, respectively. Among the agro-materials containing antifungal microorganisms, Cheongotan (Streptomyces griseus) reduced spore germination rate of V. nashicola to 88.8%; moreover, formation of appressoria or intracellular accumulation was not observed. Application of Topsid (Paenibacillus polymyxa) reduced spore germination rates in V. nashicola and G. asiaticum to 71.0% and 90.6%, respectively, and the formation of appressoria was not observed. Studying the antifungal activity of agro-materials because of cumulative applications under the field conditions is necessary, owing to their contact fungicidal effect and the induced-resistance by microbial metabolites and natural compounds.