• The Korean Journal of Mycology
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• v.18 no.2
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• pp.89-96
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• 1990

This study was conducted to find out the effects of Thiabendazole on controlling green mold causing serious damage to oyster mushroom, Pleurotus spp. during the cultivation. In vitro, the strains of oyster mushroom such as ASI 2018, 2072 and 2016 were inhibited by 500 ppm of the fungicide, but the strain of ASI 2001 and ASI 2070 was inhibited by 100 and 500 ppm on oatmeal agar, respectively. The mycelial growth of the oyster mushroom started to be inhibition by soak treatment at a 0.2g/1000 ml aqueous solution of the fungicide. When the oyster mushroom and green mold inoculated both or separately on the substrates of soak treatment, the green mold did not grow at all, but the oyster mushroom grown well. The maximum control effect of the green mold showed when $2g/m^2\;and\;5g/m^2$ of the fungicide was sprayed on the surface of substrates before pasteurization. The highest yield of the sporophores of oyster mushroom was obtained from $5g/m^2$ treatment.

• Korean journal of applied entomology
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• v.50 no.1
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• pp.79-82
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• 2011

Biological control of Aphis gossypii by natural enemies was carried out in watermelon from April to June. Aphidius colemani was released 3 times at rate of $2/m^2$ to control A. gossypii(April 24, May 8, and May 22 in 2007). In A. colemani-released plots, A. gossypii showed low population density of < 0.6 per leaf with the highest parasitism of 57.2%, and 2.0~10.6% in the percentage of leaves with aphids. In control, the population of A. gossypii kept on increasing from early May and reached 653.2/leaf on may 29.

• Korean Journal of Soil Science and Fertilizer
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• v.30 no.4
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• pp.341-344
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• 1997

To check the possibility to use the pharmaceutical by product of ginkgo leaf for the improvement soil fertility, a pot experiment was conducted with paddy rice. There were three treatment; NPK alone, NPK+7000kg(air dry)/ha of ginkgo leaf waste and NPK+700 kg of water-washed ginkgo leaf waste (air dry)/ha. The result indicated that the application of ginkgo leaf waste severely retarded the growth of rice. Water washing did reduce the severity of retardation, but the water washed ginkgo leaf waste also retarded the growth of rice significantly. The result of this study suggested that ginkgo leaf waste may contain some growth inhibiting substance.

• Applied Biological Chemistry
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• v.33 no.1
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• pp.68-72
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• 1990

Little is known about the regulation of IAA level in plants under low temperature. On exposing 6-day-old etiolated pea(Pisum sativum L. var. Sparkle) seedlings grown at $25^{\circ}$ to $5^{\circ}$ for 3 days, free IAA level decreased from 17.6 to 4.9 ng/g fresh weight(that is, from 68 to 10 pmol/shoot) and total IAA level from 113.2 to 60.8 ng/g FW. The level of free tryptophan, precusor of IAA, also decreased from 583 to 414 nmol/g FW and that of free phenylalanine and tyrosine, products of shikimic acid pathway along with tryptophan, decreased from 3,168 to 2,327 nmol/g FW. Thus low temperature was found to down-regulate the level of endogenous IAA, in part, by reducing tryptophan biosynthesis in etiolated pea shoots.

• The Korean Journal of Mycology
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• v.20 no.3
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• pp.259-268
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• 1992

Fifty-three actinomycetes antagonistic to Phytophthora capsici and Magnaporthe grisea were isolated from rhizosphere soils in six pepper-growing areas and ashore soils. Thirty-two antagonistic actinomycetes, showing inhibition zone larger than 5 mm, were classified into 20 groups according to their colony morphology and color. The antagonistic activity against P. capsici greatly varied, which showed inhibition zone sizes in the ranges from 5.7 to 17.5 mm on V-8 juice agar and from 2.5 to 17 mm on tryptic soy agar. The antagonistic activity of some actinomycetes tested was remarkably different between the two test media. The antagonists showed a relatively broad antifungal spectrum, but their antibacterial activity was negligible, except for Pseudomonas solanacearum. Butanol extracts of culture filtrates from antagonistic actinomycetes inhibited mycelial growth of P. capsici and M. grisea, thereby confirming strongly antibiotic production in culture. Culture filtrates of some antagonistic actinomycetes completely inhibited Phytophthora blight in pepper plants.

• Journal of Bio-Environment Control
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• v.12 no.2
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• pp.101-105
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• 2003

This experiment was conducted to find out the effect of day length on the production of high quality plug seedlings in onion (Allium cepa L.). Two cultivars, ‘Changnyongdaego’ and‘Wolryun’, were grown to seedlings in 200-cell plug trays under 11.5, 12.5, 13.5 hours and natural day length. These seedlings were transplanted to the pot (16 cm In diameter) and grown under 16 hours day length. Number of leaves and neck diameter showed better growth in the longer than shorter day length treatments, but plant height old sheath length were retarded in the longer day length treatments. Growth such as no. of leaves, neck diameter, plant height and sheath length increased with the passage of day, but plant height and neck diameter decreased by treatment over 20 days with 13.5 hours day length. Bulbing and bulb size of onion after transplanting were enhanced in the seedlings cultured under longer day lengths. From the above results, treatment of long day length during seedling culture in plug tray can control the overgrowth and produce high quality plug seedlings.

• Research in Plant Disease
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• v.13 no.3
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• pp.197-203
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• 2007

An isolate of Ampelomyces quisqualis 94013(AQ94013) was selected as an effective parasite for biological control of cucumber powdery mildew. In the greenhouse, occurrence of cucumber powdery mildew was significantly suppressed for nine days by pre-treatment with $5.0{\times}10^6/ml$ and $5.0{\times}10^7/ml$ of conidial suspension of AQ94013. The disease was effectively controlled within three to seven days by post-treatment with the $5.0{\times}10^6/ml-conidial$ suspension of AQ94013. When AQ94013 was treated at concentration of $5{\times}10^6/ml$ three times at seven-day interval in the vinylhouse, the control effect was higher than that treated twice at ten-day interval and that treated with fenarimol twice. As the results, Ampelomyces quisqualis 94013 could be a prospective biofungicide for biological control of powdery mildew of cucumber.

• Research in Plant Disease
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• v.20 no.2
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• pp.101-106
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• 2014

Citrus canker caused by Xanthomonas citri subsp. citri (Xcc) is one of the most important diseases on citrus. Although Satsuma mandarin cultivating mostly in Korea is moderately resistance to canker, occurrence of the disease were more frequently reported since last decade. Like other diseases in citrus, citrus canker was mainly protected by chemical fungicide in the field. Due to the side effect of the chemicals, alternative method of disease control is recently required. In this study four rhizobacterial strains TRH423-3, MRL408-3, THJ609-3 and TRH415-2 are selected by testing its antifungal activity against Xcc. Pre-inoculation with the selected rhizobacterial strains caused disease suppression on the citrus leaves after inoculation with the citrus canker pathogen. Similarly, in the field test symptoms of citrus canker were less developed in the citrus trees applied several times with the selected rhizobacterial strains compared with those of untreated trees. Therefore, it is suggested that the selected rhizobacterial strains may be valuable as an alternative method in the environment-friendly citrus farm.

• Journal of Mushroom
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• v.15 no.3
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• pp.124-128
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• 2017

The fruiting bodies of Sanghwang mushrooms, Phellinus linteus HN1009K (PLH) and Phellinus linteus (Korea Sanghwang, PLK), and Phellinus baumii (Jangsu Sangwhang, PB), were extracted with 70% methanol. The methanolic extracts of different concentrations ($5-200{\mu}g/ml$) showed inhibitory effects of 20-95% on plated aggregation induced by collagen (2.5 ug/ml), ADP (10 uM), and thrombin (0.1 U/ml). The PLH, PLK, and PB extracts (200 ug/ml) reduced ATP release from ADP-activated platelets by 50-60%. These results suggest that the methanolic extracts from Sanghwang mushrooms inhibit platelet aggregation.

• Applied Biological Chemistry
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• v.16 no.2
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• pp.94-98
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• 1973

1. Tomato variety used was Bogsu No. 2 and it was grown in field. Experiments were conducted in 1971 and 1972 to examine the changes of $CO_2$ product on in each growth-period and the contents of acid, sugar and vitamine C during storage. 2. By controlled atmospheric pressure the effects of respirationreduction in tomato fruits were the most effective at 660 Torr. part. 3. $CO_2$ production of tomato fruits harvested at each growth-period was differently changed at each growth-period and $CO_2$ production in tomato fruit at the same maturity from the plant showed Sigmoid type. 4. $CO_2$ production of tomato fruits harvested at the same ripeness score was in influenced by controlled atmospheric pressure during growth period and $CO_2$ production was reduced at SAP part compared with NAP part during the full growth-period. 5. The change of weight in tomato fruits was decreased in NAP part than in SAP part during storage and contents of acid, sugar, and vitamine C showed the same tendency.