• The Korean Journal of Mycology
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• v.26 no.3 s.86
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• pp.365-372
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• 1998

In this study, we evaluated the genetic relationships of fourty seven Pestalotiopsis theae isolates collected from diseased sweet persimon in various places in southern part of Korea using RAPD (Randomly Amplified Polymorphic DNAs) method. As a result of the amplification, eight primers showed total of 86 bands ranging from 0.3 Kb to 3.2 Kb. Among those 86 bands, 84 polymorphic bands were used for bionominal matrix code (0, 1), and UPGMA dendrogram analysis. Similarities among the compared isolates ranged from below 60% to more than 95%. Most of the compared isolates showed $50{\sim}80%$ similarities. The number of isolate pairs which showed more than 80% similarity were 248. The number of isolate pairs which showed $50{\sim}80%$ similarity were 789, and the number of isolate pairs which showed below 50% similarity were 21. Isolate SP-21 (No.9) showed below 50% similarity with all the isolates compared. At 50% similarity level, all the isolates compared, except isolate SP-21 (No.9), were included in one big group. At 65% similarity level, all the isolates compared, except isolate SP-21 (No.9), were divided into three different groups. At 75% similarity level, all the isolates compared, except isolates SP-47 (No. 23) and SP-21 (No.9), were divided into six different groups.

• The Korean Journal of Pesticide Science
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• v.5 no.4
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• pp.50-56
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• 2001

In vitro experiments, several fungicides including prochloraz, tebuconazole, fluazinam, fludioxonil, and iminoctadine-triacetate showed more than 85% inhibition of mycelial growth of Pestalotiopsis theae (SP-3). Dichlofluanid and chlorothalonil inhibited mycelial growth at the rate of 10 and 33%, however benomyl did not inhibit mycelial growth of the fungus. Minimum inhibitory concentration(MICs) of iminictadine-triacetate on the mycelial growth of SP-3 isolate was $10{\mu}g/m{\ell}$, but that of P. theae $\underline{MAFF}$ 752002 and P. longiseta $\underline{MAFF}$ 752001 was $1{\mu}g/m{\ell}$. MIC of benomyl, chlorothalonil, dichlorofluanid was $1,000{\mu}g/m{\ell}$, and that of fludioxonil, fluazinam, tebuconazole was $10{\mu}g/m{\ell}$. Conidial germination was inhibited more than 80% in tile medium which contained $1{\mu}g/m{\ell}$ of prochloraz, tebuconazole, fluazinam, fludioxonil, and minoctadine-triacetate. Control values of benomyl, chlorothalonil and dichlofluanid were 40, 60 and 30%, respectively. The controlling effect of iminoctadine-triacetate ($10{\mu}g/m{\ell}$) aganist P. theae (SP-3) in leaf disc test was more than 93%, but benomyl and dichlofluanid could not control leaf blight disease caused by P. theae (SP-3). Tebuconazole, fluazinam, fludioxonil, and iminoctadine-triacetate showed more than 94% of protective and curative effect of leaf blight of sweet persimmon, while, benomyl and dichlofluanid did not show any control effect of the disease.

• Korean Journal Plant Pathology
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• v.14 no.2
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• pp.120-124
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• 1998

The conidial germination of Pestaotiopsis theae was occurred in cells attched with pedicels, the inferior cell of conidium. The cells were swollen like a ball, and then germinated in 4 hours under favorable conditions. Generally, it was considered that fifty percent of whole conidia was germinated in the range 6~12 hours. The optimum temperature and pH for conidial germination of P. theae (SP-3) causing leaf blight on sweet persimmon was $25^{\circ}C$ and pH 5, respectively. Conidial germination rate was higher than 90% at 100% relative humidity, but never germinated at a relative humidity lower than 88.5%. Conidial germination was highest at the concentration of 1~4$\times$104 conidia/ml. In case of cultural media, the conidial germination was higher than 90% on PDA, PSA, OME and Leonian agar. There was no relationship between light and conidial germination. It was concluded that the key environmental factors affecting conidial germination of the fungus (SP-3) were temperature and moisture.

• Korean Journal Plant Pathology
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• v.13 no.4
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• pp.232-238
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• 1997

Culture conditions affecting mycelial growth and sporulation of P. theae, SP2, SP3 and P. longiseta which causing leaf blight on oriental persimmon leaf blight have been investigated. The optimum temperature for the mycelial growth and sporulation on potato dextrose agar was $25{\sim}30^{\circ}C$ in all the fungi, but was inhibited and finally arrested at 10 and $30^{\circ}C$. The optimum pH for mycelial growth and sporulation were ranged at pH 4.5~5.0 and 5.0~6.0 in all the fungi. Lenonian agar, potato sucrose agar and oatmeal medium were good culture media for the mycelial growth and sporulation of all the fungi. The effective sources of nitrogen and carbon for the mycelial growth were tryptone, glycine, starch, dextrose, galactose and lactose. Glutamic acid, peptone and tryptone were good nitrogen sources for sporulation of the fungi. Sucrose, starch and galactose were also good carbon sources for sporulation. Generally, vitamins had no effect on mycelial growth and sporulation. The pH of the potato dextrose broth inoculated with SP2, SP3 and P. theae and P. longiseta was changed from 7.0 to 4.5~4.7 and 5.0~5.4 after incubating for 10 days, respectively. But, the initial pH of the medium adjusted to 5.0 was lowered to 4.5~4.7 after incubating for 10 days.

• Journal of the Korean Wood Science and Technology
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• v.47 no.4
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• pp.459-471
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• 2019

Several species of Aquilaria and Gyrinops are native to Indonesia and well known as agarwood-producing trees with a high economic value. Their bioactive compounds have a wide spectrum of uses, such as in medicine and cosmetics. These genera have undergone extensive search for novel bioactive compounds. The purpose of this study was to isolate, identify, and characterize the endophytic fungi community associated with Aquilaria malaccensis, A. microcarpa, Gyrinops versteegii, and A. crassna trees and investigate their bioactive properties as antioxidant agents and antagonists. A total of 50 fungi were successfully isolated from different tissues of the four species of agarwood-producing trees. Two isolates exhibited strong antioxidant activity, namely, Apodus oryzae (R2MC3A, $IC_{50}$ 60.92 mg/mL) and Diaporthe sp. (P1DS1[C], $IC_{50}$ 76.65 mg/mL). Two isolates, Pestalotiopsis theae (P3BS3[B]) and Curvularia sp. (P2CD3A), showed >75% antifungal activity against pathogenic Fusarium solani. The results revealed that endophytic fungi associated with the studied agarwood-producing trees had potential antioxidant and antifungal activities for further applications in biotechnology.