• The Korean Journal of Pesticide Science
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• v.21 no.1
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• pp.26-32
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• 2017

Antimicrobial activity of 6 phosphate compounds as $H_3PO_3$, $H_3PO_4$, $K_3PO_4$, $K_2HPO_4$, $KH_2PO_4$ and $NH_4H_2PO_4$ against Phytophthora capsici JHAW 1-2 and Colletotrichum acutatum JC24 was investigated in this study. Inhibitory effect on zoospore release, zoosporangia germination and zoospore germination was superior than mycelial growth. Among 6 compounds, $H_3PO_3$ and $H_3PO_4$ showed the best antimicrobial activity against P. capsici JHAW 1-2. Diseases controlling activity of the phosphate compounds tested on seedling and fruit of pepper against Phytophthora blight was also better than those against anthracnose. When $H_3PO_3$ was applied to the pepper seedlings at a concentration of $100{\mu}g\;mL^{-1}$, severe phytotoxicity was occurred. However, with applying $10{\mu}g\;mL^{-1}$ of $H_3PO_3$ showed 100% the disease control efficacy. In case of $100{\mu}g\;mL^{-1}$ $H_3PO_4$ application showed excellent antimicrobial activity against P. capsici JHAW 1-2, and 56.7% of the disease control efficacy with no phytotoxicity. To investigate the control efficacy against anthracnose, conidia suspension was inoculated with non-wound and wound inoculation method on pepper fruit. Among 6 compounds, only $100{\mu}g\;mL^{-1}$ of $H_3PO_3$ and $H_3PO_4$ had a activity of more than 70%, but the control activity on other treatments was minimal or unacceptable.

• Korean Journal of Environmental Agriculture
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• v.37 no.1
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• pp.34-40
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• 2018

BACKGROUND: In order to select a fungicide that can effectively control anthracnose disease in Japanese plum fruit, mycelial growth inhibition effect and spore germination inhibition effect of six fungicides were tested in vitro against six isolates of Colletotrichum acutatum and five isolates of C. gloeosporioides that were isolated from diseased Japanese plum fruit. METHODS AND RESULTS: Inhibitory effects of fungicides on mycelial growth were investigated after inoculating each isolate on potato dextrose agar amended with four discriminatory concentrations of each fungicide for 7 days at $25^{\circ}C$. For spore germination inhibitory effect, each isolate of the Colletotrichum spp. was cultured in potato dextrose agar for 7-14 days at $25^{\circ}C$. After adjusting the concentration of spores of each isolate to $1{\times}10^6mL^{-1}$ by diluting with 0.025% PDB, the spore suspension was mixed with each fungicide (1:4, v/v), and $60{\mu}L$ aliquots were dispensed to sterile hole slide glass. Hole slide glasses were placed in a humidified box and incubated for 15 hours at $25^{\circ}C$. Then, spore germination was observed under an optical microscope. At recommended concentration of fungicide prochloraz manganese showed the highest mycelial growth inhibitory effect and dithianon showed the lowest mycelial growth inhibition. The $EC_{50}$ values for the inhibition of spore germination by dithianon and pyraclostrobin were $0.069-0.126{\mu}g/mL$ and $0.37-1.59{\mu}g/mL$, respectively. Although benomyl, prochloraz manganese, azoxystrobin, and tebuconazole did not inhibit the spore germination, they appeared to restrain mycelial growth by abnormal growth of germ tube and mycelium after germination. CONCLUSION: Dithianon seemed to have preventive effect. Prochloraz manganese, azoxystrobin, and tebuconazole were likely to have control effect. Pyraclostrobin is considered to have both preventive and control effect against anthracnose disease of Japanese plum fruit.

• Korean Journal of Medicinal Crop Science
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• v.11 no.1
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• pp.53-61
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• 2003

Cirsium japonicum var. ussuriense were extracted with methanol and then fractionated with nhexane, EtOAc and BuOH to get active fractions. And their antioxidant and antimicrobial activities in each fraction were determined. Ethyl acetate and butanol fraction of Cirsium japonicum var. ussuriense showed strong antioxidant activities, but hexane fraction did not show any activities. But in the antimicrobial test, Ethyl acetate fraction showed strong antimicrobial activities except to Aspergillus awamori, Asperigillus niger. Especially, Ethyl acetate fraction showed the strongest activities against Bacillus subtilis. And aqueous fraction showed the strongest activities against Cladosporium herbarum, Hypocrea nigricans. This study was performed to determine the antimutagenic and cytotoxic effect of Cirsium japonicum var. ussuriense methanol extract on Salmonella typhimurium TA98, TA100 and cancer cell lines using Ames test and cytotoxicity assay, respectively. Cancer cell lines include human lung carcinoma(A549), human breast adenocarcinoma(MCF-7) and human hepatocellular carcinoma (Hep3B). Futher fractionations with hexane, ethyl acetate, butanol and water from methanol extract of Cirsium japonicum var. ussuriense were performed to obtain effective fraction, methanol extract showed 60.14% inhibition effect on the mutagenesis induced by MNNG against TA100, while 77% and 72.5% inhibition was observed on the mutagenesis induced by 4NQO against TA98 and TA100, respectively. and methanol extract showed 82.25% and 73.7% inhibitory effect on the mutagenesis induced by Trp-P-1 against TA98 and TA100, respectively. methanol extract showed the strongest effect against A549, MCF-7 and Hep3B at the same concentration compared to those of other fration.

• Journal of Korean Society of Forest Science
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• v.64 no.1
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• pp.33-41
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• 1984

This study was conducted to examine the physiology of pine mushroom mycelia cultured with various media for artificial culture of pine mushroom. The results obtained were as follows: 1) Among the various media, the medium composed of honey, boiled pine mushroom and soil extract fluid, fibrous root extract fluid, dry yeast, $KH_2PO_4$ inositol, folic acid, and biotin was the best for the growth of pine mushroom mycelium. 2) The optimum temperature for germinating pine mushroom spore and for culturing pine mushroom mycelium, was $24^{\circ}C$ and the optimum pH was 4.5. 3) There was no significant difference in growth between the mycelium separated from the tissue of pine mushroom sporophore and that separated from the spore. 4) No noticeable effect was found on the growth if such salts as $ZnSO_4$, $MnSO_4$, $MgSO_4$, $CaCl_2$ and ferric citrate were added to the Hamada's medium. 5) The addition of fibrous root extract promoted the growth of pine mushroom mycelium. 6) As a carbon source of artificial media, honey was more effective than glucose. 7) The culture infiltration of Mortierlla growing often in Fairy Ring was good for the growth of mycelium compared with the control. 8) The addition of fibrous root extract, inositol, biotin, and folic acid to artificial culture media was greatly effective in growth. When the temperature was lowered $19^{\circ}C$ after mycelium has appeared, the formation of primordium was observed.

• Journal of fish pathology
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• v.2 no.2
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• pp.53-70
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• 1989

An ovarian parasite, Marteilioides chungmuensis of the Pacific oyster, Crassostrea gigas has been observed on several occasions in the Pacific sector of production of this oyster species(Matsuzato et al., 1977 ; Chun, 1979). This study was carried out on the specimens collected at Hwado, Och'$\check{o}$n, and Sinchang respectively located the southern, western, and eastern coasts of Korean Peninsula from 1986 through 1988 to investigate M. chungmuensis to the Pacific oyster. Uitrastructural studies were also carried out on infected oysters, to allow detailed examination of the structure and consepuently the systematic position of this parasite. Infection rates of M. chungmuensis at Hwado and Och'$\check{o}$n oyster farms were 5.3% and 4.2% each in 1986, 6.7% and 2.8% each in 1987, but they were not found at Sinchang oyster habitat. M,. chungmuensis-infected oysters were found from June to November at Hwado and from June to October at Och'$\check{o}$n. Twenty five of three hundred oysters transplanted from Sinchang to Hwado were found infected with M. chungmuensis. Some abnormal eggs infected with M. chungmuensis are liberated through the gill together with normal mature eggs on the spawning and the rest remain necrotized after spawning season. The earliest known stages consist of a stem cell or primary cell, including a secondary cell in which ovoid haplosporosomes are found. During sporulation, 2 or 3 secondary are produced by exogenous budding from the first secondary cell and, each secondary cell evolves into a sporont upon the tertiary cell differentiation (enodogenous budding) ; then, haplosporosomes are formed in the young sporont. Internal cleavages involve the differentiation of one tricellular spore per sporont. The outermost spore cell contains membrane-bounded osmiophilic bodies : the middle and the inner, most spore cells contain high density cytoplasmic ribosomes. The mechanism of spore formation from the stem cell of M. chungmuensis is the simplest of the class Paramyxea known up to now.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.31 no.2
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• pp.129-142
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• 1986

Fifty-five local collections of buck wheat, Fagopyrum esculentum, were investigated their ratios of long-styled (LS) and short-styled (SS) flowers, fertility, meiosis of megaspore and microspore mother cell, female and male gametogenesis, and egg apparatus in accordance with the sowing seasons (spring, summer), altitudes (20m, 50-100m, 300m), and parent style types (L, S). Also they were embryologically investigated the fertility, fertilizing phenomenon and proembryogenesis by the legitimate and illegitimate pollination. There were no differences in the ratios of long-styled and short-5tyled flowers along with altitudes, but more irregularness was observed in plain area than that in the mountaineous or coastal area. LS versus SS ratios by sowing seasons were significantly separated into 1 : 1 in the summer sowing (P 0.1), but they were irregularly separated in the spring sowing. The segregating ratios by parent style types showed more number of short-styled flower in the spring sowing, and were statistically seperated into 1 : 1 in the summer sowing (P 0.25), regardless to parent style types. In the artificial legitimate union, the seed setting rates of the summer sowing (59-61%) were much higher than those of the spring sowing (about 30%), but in the artificial illegitimate union the seed setting rates were only fructified about 0.8-1.8% in the spring sowing. The seed setting rates in accordance with flowering stages were larger in turn early, middle, late, in the summer sowing. The grain number and grain weight per plant of short-styled flower were more than those of long-styled one regardless to style types. The 1,000 grain weight of long-styled flower was heavier than that of short-styled one in large grain, but it was lighter than that of short-styled flower in small or medium grain. The percentage of normal female and male gametogenesis in the summer sowing were higher than those in the spring sowing. The ovule was atropous and two polar nuclei were a synkarion before flowering. The pollens germinated at 30 minuts after pollination and the pollen tube grew continually and penetrated into micropyle at 1.5-2 hours and the two male nuclei fertilized with egg nucleus at 3 -5 hours after pollination. Flertilizing times in summer were shorter than in autumn. The fertilized egg was divided in a small apical cell toward the interior of the embryo sac and a large basal cell toward the micropyle cell at 15-24 hours after pollination, and division times in summer were shorter than in autumn. The proembryo began the embryogenesis at 7-8 days and formed itself into the perfect embryo at 15 days after pollination.

• The Korean Journal of Pesticide Science
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• v.5 no.2
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• pp.37-44
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• 2001

The biological effects of the iminoctadine tris (albesilate) and kresoxim-methyl for the protection of citrus postharvest diseases caused by penicillium spp. were assayed. In vitro tests, $EC_{50}$ values of iminoctadine tris(albesilate) were $0.01{\sim}0.02\;and\;0.01{\mu}g$ a.i./mL against mycelial growth of P. italicum and P. digitatum, respectively, but iminoctadine tris(albesilate) at $0.64{\mu}g$ a.i. /mL inhibited a little mycelial growth of unknown Penicillium sp. which produced another symptom different to blue and green mold caused by P. italicum and P. digitatum, respectively. And against germination and growth of germ tube of P. italicum and P. digitatum, $EC_{50}$ value of iminoctadine tris(albesilate) was $0.0013{\sim}0.0025{\mu}g$ a.i./mL. But spore germination of unknown Penicillium spp. was not nearly inhibited at $0.2{\mu}g$ a.i./mL. $EC_{50}$ values of kresoxim-methyl were $0.08{\sim}0.16$, 0.04 and $0.16{\mu}g$ a.i./mL against mycelial growth of P. italicum, P. digitatum and unknown Penicillium sp., respectively, and $0.04{\sim}0.08{\mu}g$ a.i./mL and $0.01{\sim}0.02{\mu}g$ a.i./mL against germination and growth of germ tube of P. italicum and unknown Penicillium sp., and P. digitatum, respectively. Iminoctadine tris(albesilate) and kresoxim-methyl were markedly effective to control the postharvest disease by 7 days spray prior to harvest. When the fruits were sprayed with iminoctadine-tris(albesilate) ($200{\mu}g$ a.i./mL) and kresoxim-methyl ($155{\mu}g$ a.i./mL) 7 days prior to harvest and subsequently stored for 90 days, the percentage of diseased fruit by Penicillium spp. was $3.6{\pm}1.8%$ in treatment of kresoxim-methyl and $5.9{\pm}1.8%$ in iminoctadine-tris(albesilate), respectively. On the other hand, tile percentage of diseased fruit was relatively high, $20.3{\pm}10.0%\;and\;19.5{\pm}9.6%$ in thiophanate-methyl ($700{\mu}g$ a.i./mL) and non-treatment, respectively. Maximum residue amount (ppm) among fruits (flesh and peel) assayed 0, 30, 60 and 90 days after storage was 0.45 and 0.10 ppm in treatment of kresoxim-methyl and iminoctadine, respectively.

• Korean journal of applied entomology
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• v.4
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• pp.11-18
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• 1965

In order to investigate the fungicidal activities against various plant pathogenes, diminishing effect of plant transpiration, phytotoxicities, vapor effect and the rate of reduction by ultraviolet rays of phenylmercuric 8-oxyquinolinate(P.M.Q), this experiments were undertaken under various laboratory conditions. 1. Inhibitory activity on the spore germination of this chemical was shown less effective than that of P.M.A..(Table 2, Table 3, Table 4, Table 5 and Table 6) Also, P.M.Q. was resulted a somewhat higher inhibitory activity on the hyphae growth than P.M.A. (Table 7). 2. In the diminishing effect of plant transpiration, 8-hydroxyquinoline sulfate(oxine sulfate) was more strong inhibitory at first than P.M.Q., while, at last, P.M.Q. was more strong inhibitory in comparison with oxine sulfate(Table 8, Fig. 1 and Table 9). 3. P.M.Q. was shown less injury on the germination of rice plant seeds and the emergence of their roots than P.M. A.(Table 10). Injuries was not observed on the rice seedlings and soy-bean seedlings sprayed with 40 ppm of this chemical. 4. P.M.A. had more inhibitory effects on the mycelial growth of phytopathogenes than P.M.Q. on the vapor effect (Table 11, Fig. 2). 5. Biological activity and chemical decomposition rate of P.M.A. were greatly reduced by exposure of this compound to ultraviolet rays. But, P.M.Q. was only slightly affected by similar treatment(Table 12, Fig. 3, Table 13 and Fig. 4). From the above results, this chemical will be a promising fungicide adding fungitoxicities against various phytopatho genes, diminishing effect of plant transpiration and physico-stability.

• Journal of Mushroom
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• v.3 no.3
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• pp.95-99
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• 2005

Carbon dioxide($CO_2$) promotes development of primordia and depress differentiation of sporophore and gill containing basidia, have an effect on quality. This experiments were conducted to elucidate optimal level of $CO_2$ for king oyster mushroom(Pleurotus eryngii). King oyster mushroom was cultivated under 1,600, 2,400, and 3,200ppm $CO_2$. Harvest ratio in normal plot were 98.6, 99.3, and 93.8% at 1,600, 2,400, 3,200ppm, respectively, so 2,400ppm is optimal. The yield per bottle was 102.5g at 2,400ppm, better than 99.7g at 1,600ppm, The $CO_2$ concentration of 2,400ppm was also the best condition for quality, 6.1 at 2,400ppm was 115% of 1,600ppm's. In thinning treatment plot, quality at 2,400ppm was 9.5 better than 1,600ppm whose quality was 9.4. The yields per bottle were 90.7, 98.2, 77.3g at 1,600, 2,400, 3,200ppm respectively. These results show that 2,400ppm was optimal $CO_2$ concentration for quantity of King Oyster mushroom as well as quality.

• Research in Plant Disease
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• v.26 no.1
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• pp.8-18
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• 2020

Red pepper, one of the major economic crops in Korea, is being affected by anthracnose disease caused by Colletotrichum acutatum. To control this disease, an antagonistic bacterial strain, Bacillus subtilis YGB36 identified by 16S rDNA sequencing, physiological and biochemical analyses is used as a biological control agent. In vitro screening revealed that the strain YGB36 possess strong antifungal activity against the pathogen Cylindrocarpon destructans. The strain exhibited cellulase, protease, amylase, siderophore production and phosphate solubility. In vitro conidial germination of C. acutatum was most drastically inhibited by YGB36 cell suspensions (10⁶ cfu/ml) or culture filtrate. Development of anthracnose symptoms was reduced on detached immature green pepper fruits by treatment with cell suspensions, and its control value was recorded as 65.7%. The YGB36 bacterial suspension treatment enhanced the germination rate of red pepper seeds and promoted root development and growth under greenhouse conditions. The in vitro screening of fungicide and insecticide sensitivity test against YGB36 revealed that the bacterial growth was not affected by any of the insecticides, and 11 fungicides out of 21 used. Collectively, our results clearly suggest that the strain YGB36 is considered as one of the potential biocontrol agents against anthracnose disease in red pepper.