• Current Research on Agriculture and Life Sciences
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• v.3
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• pp.129-150
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• 1985

The present investigation was conducted to provide a systematic approach necessary to establish an integrated insect pest management program of barley in Korea. Some ecological surveys on insect pests of barley have been undertaken at the field of Experimental Station, Ky$\check{o}$ngbuk Provincial Office of Rural Development as a fixed point survey area, and at 23 localities for round survey throughout southern and central Korea from 1983 to 1984. Previously known insects injurious to barley in Korea were revised and the population dynamics of 10 dominant harmful species were analyzed according to either 24 localities or 25 cultivars respectively by using several sampling methods of net sweeping, black light traps, yellow water pan traps and visual counting. As the results, a total of 94 species belonging to 77 genera under 32 families are known to be injurious to barley, among them 20 species are newly added here. In the population density level, the dominant species were disclosed as Laodelphax striatellus (43.1 %), Macrosiphum avenae(27.0 %), Rhopalosiphum padi(6.5 %), R. maidis(5.4 %), Psammolettix strialus(2.7 %), Chlorops oryzae(2.2 %), Agromyza albipennis(2.1 %) Phyllotreta nemorum(1.4 %), Chaetoenema cylindrica(1.0 %), Dolycoris baccarum(1.0 %) in order. For the general abundance of major insect pests, it was highest in the cultivar P'aldal whereas lowest in Milyang #22. There were tendencies that Psammotettix striatus, Dolycoris baccarum, Phyllotreta nemorum and Chaetocnema cylindrica represented a maximum increase in the beginning of June, while Chlorops oryzae and Agromyza albipennis showed in the middle of May but aphids were in the end of May. In the dominance of natural enemies, Nabis stenoferus occupied 21.4 % and Propylaea japonica 9.6 %.

• Korean journal of applied entomology
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• v.22 no.4 s.57
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• pp.300-306
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• 1983

Effect on blast lesion development was investigated in rice cultivar Milyang 23 and Jinheung using two races of Pyricularia oryzae compatible or incompatible to each of two rice cultivars. Discase lesions were measured in rice when inoculated with inoculum mixed with compatible and incompatible races, inoculated with a compatible race following with an incompatible race and vice versa. Lesions were smaller when rice was incoulated with an incompatible race and then inoculated with a compatible race than those inoculated in the reverse way both at the inoculated site and at 3cm-upper part from inoculated spot. The results suggested that induced resistance might play a role in suppression of lesion development although such an effect appeared to be influenced by heavy application of nitrogen fertilizer.

• Korean Journal of Food Science and Technology
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• v.14 no.4
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• pp.375-381
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• 1982

The studies are conducted on the changes of soybean lipids in terms of physicochemical characteristics, lipid classess and fatty acid composition during the fermentation process of soybean Koji preparation for daenjang (soybean paste) in a model system using cooked soybean inoculated by Aspergillus oryzae. The total lipids contents were increased during soybean Koji preparation, generally iodine values decreased but acid values increased. Total lipids of soybean Koji consisted of about 90.6% neutral lipids, 7.6% phospholipids and 1.8%, glycolipids indicating that phospholipids contents of soybean Koji was increased when compared to those of cooked soybean. The major components of nonpolar lipids in soybean Koji were free fatty acids(39.6%) and triglycerids(29.2%). Free fatty acids increased as the triglycerides decreased during soybean Koji preparation by the hydrolysis of lipase action. The major components of polar lipids in soybean Koji were phosphatidyl choline and phosphatidyl ethanolamine. Differences were observed in the composition of the polar lipids of cooked soybean and soybean Koji. A little changes also occurred in fatty acid compositions of total lipids, triglycerides and free fatty acids fractions in soybean Koji preparation. Especially a considerable increase of linoleic acid in free fatty acid fraction was observed in soybean Koji.

• 보존과학연구
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• s.22
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• pp.5-25
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• 2001

The germicidal and insecticidal properties of volatile components extracted from star anise(Illicium verum Hooker filius) and clove (Eugenia caryophyllata THUNBERG)were evaluated against five microorganisms and three insects for the purpose of developing biocidal active substances from medicinal plants. The volatile components of star anise and clove showed strong antimicrobial effect against Aspergillus niger, Penicillium funiculosum, Mucor hiemalis, Trichoderma viride, and Aureobasidium pullulans. The extracts of each medicine also showed insecticidal effects against Sitophilusoryzae L., Lyctus linearis GOZE, and Reticulitermes spertus kyushuensis Morimoto. Fumigant toxicities to adult insects were determined. In the case of fumiganttoxicity, the extract of star anise showed 100% mortality against R. spertus, S.oryzae, and L. linearis at rates of $2.5\mu\ell$, $50\mu\ell$, $250\mu\ell$/filter paper, respectively but showed no killing effects by clove. The volatile components of star anise and clove were investigated by means of GC/MS. The main constitute, anethole among 20components from star anise and eugenol among 9 components from clove were identified. The mixture of star anise and clove as the volume ratio of 2 : 1 showed higher properties for antimicrobial and insecticidal effect than each volatile component. A. niger was inhibited by the mixture(125ml/$m^3$) for up to 10 days of exposure. Also, from the result of observing state change of organic materials by volatile extracts of star anise and clove, volatile extracts effects have no effect on natural organic materials of organic cultural properties and can be used as biological control agent. As research contents as above, the insecticidal and germicidal agents from star anise and clove and the mixture of them were more efficient and high level to prevent biological damage for conservation of organic cultural properties. So they may be used in new development of biologicalinsecticidal and germicidal agents for conservation of cultural properties.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.105.3-106
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• 2003

Bacillus subtilis strain BAC02-4 was tested for its ability induced systemic resistance(ISR) in rice against Magnaporthe grisea We extend these studies to investigate the biological induction of systemic resistance in rice following treatment with the inducer isolate BAC02-4 and naturally infested with Pyricularia oryzae. We also determine levels of ISR activity during the period between disease development and the onset of systemic resistance. Comparition of lesion number according to applied concentration of BAC02-4 to 'Nagdongbyeo' when naturally infested with the conidia of P. grisea. Results from the blast nusery trial using the 'Nagdongbyeo' showed very low rice blast severity with the inducer concentration of 10$\^$8/ cfu level. Considering the low level of treatment and untreated control were observed to have developed typical susceptible lesion type. Highest protection against the rice blast pathogen when applied three times with 5 days interval as root drench at 5 to 6 leaf stage before pathogen challenge. But higher dose of bacterial inducer produced a little stunted plants with less number lesions and delayed disease development. Diseased leaf area of treated with suspension of the isolate which gave about 80％ of control efficacy at 20 days later comparable to that in noninfested, inducer-free soil.

• Mycobiology
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• v.48 no.3
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• pp.169-183
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• 2020

Nigrospora is a monophyletic genus belonging to Apiosporaceae. Species in this genus are phytopathogenic, endophytic, and saprobic on different hosts. In this study, leaf specimens with disease symptoms were collected from host plants from the Shandong Peninsula, China. The fungal taxa associated with these leaf spots were studied using morphology and phylogeny based on ITS, TEF1, and TUB2 gene regions. In this article, we report on the genus Nigrospora with N. gorlenkoana, N. oryzae, N. osmanthi, N. rubi, and N. sphaerica identified with 13 novel host associations including crops with economic importance such as bamboo and Chinese rose.

• Korean Journal of Soil Science and Fertilizer
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• v.12 no.3
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• pp.133-139
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• 1979

In order to evaluate the effect of developed Nk compound fertilizers, 17-0-17 granular and powder, and 17-0-14 granules in comparison with single fertilizers, urea and potassium on rice (Oryzae sativa) ; cultivar, Milyang 23, (Orizae Sativa), a field experiment was carried out. Results obtained are as follows : 1. The top dressing of NK compound fertilizers tended to produce higher paddy yield than that of single fertilizers; urea and patasstum muriate. 2. The absorption of potassium and nitrogen by rice plant from the plot of NK granular compound fertilizer, 17-0-17, was greater than from the plots the absorption of those elements received other types of ferilizers and application method The absorded K/Ca+Mg ratio in milli equivalent basis in plant was also appeared to be in same order as the absorption of nitrogen and potassium. 3. From the results of present study it seemed necessary to evaluate the NK compound fertilizer for the top dressing at effective tillering stage of rice as well.

• Korean journal of applied entomology
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• v.30 no.2
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• pp.130-130
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• 1991

현미를 사료로하여 네가지 정온도조정에서(25, 28, 34, 36$^{circ}C$ $pm$0.5$^{\circ}C$, RH 70%)에서 거짓쌀도둑(Tribilium castaneum Herbst)의 각 충태별 평균발육기간($\pm$SE)을 산출하였으며, 이를 기초로하여 발육임계온도를 추정하였다. 난의 평균발육기간은 각 온도에서 7.6$\pm$0.25, 4.8$\pm$0.10, 3.0$\pm$0.03, 2.5$\pm$0.09일, 유충에서 각각 53.3$\pm$1.49, 33.4$\pm$0.57, 30.6$\pm$0.70, 31.0$\pm$1.18일, 용에서 각각 12.1$\pm$0.17, 7.8$\pm$0.09, 5.0$\pm$0.07일로 산출되었으며, 난에서 성충우화시기까지의 전발육기간은 각각72.3$\pm$1.67, 46.0$\pm$0.05, 39.4$\pm$0.64, 38.7$\pm$1.15일로 산출되었다. 난과 용의 발육기간은 밀과 옥수수같은 다른 식이조건에서와 유사하였으나, 섭식을 하는 유충기의 발육은 밀보다 현미에서 상대적으로 지체되는 현상을 보였다. 한편 현미를 섭취했을 경우, 밀을 섭취했을 때 보다 발육중 치사율이 높아 밀에 비해 현미가 저급의 식물임을 보여주었다. 거짓쌀도둑 난, 유충 용 및 전발육기간의 저온발육임게온도는 각 충태 공히 20.0$^{\circ}C$로 산출되었으며, 유충과 전발육기간의 고온발육임계온도는 각각 40.2$^{\circ}C$와 41.9$^{\circ}C$로 추정되었다. 영기수는 온도에 상관없이 최빈치 7회를 나타냈지만, 온도의 상승에 따라 7회 이상 탈피하는 비율이 높아지는 경향을 보였다. 성비는 온도와 무관한 것으로 나타났다.

• Korean Journal Plant Pathology
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• v.3 no.2
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• pp.131-136
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• 1987

Rates of lesion development over time and disease gradients over distance for blast disease on the two rice varieties, Brazos and M-20 1 were significantly affected by two different cultural conditions, upland and flooded conditions. Flooding rice field plots lowered the rates of lesion increase and flattened the disease gradients for both varieties. Despite absence of statistically significant differences in the rate of lesion increase between four sampled distances from infection focus, rate of lesion development tended to be slightly greater as distance from the infection focus increases. Rate of lesion increase was greater with more susceptible variety M-201 than with Brazos. Disease gradient was steeper for M-201 than for Brazos. As blast disease progressed, disease gradients became flattened regardless of variety due to the infections originated from secondary foci. Between two empirical disease gradient models examined, Kiyosawa & Shiyomi model was fitted better over Gregory model. Rates of blast isopath movement under upland conditions were calculated as approximately 0.2m/day and 0.4 m/day for Brazos and M-201, respectively. The results in this study suggest that differences in varietal resistance to blast could be detected by measuring disease gradient as efficiently as by measuring infection rate.

• Journal of Microbiology and Biotechnology
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• v.9 no.5
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• pp.624-630
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• 1999

In order to investigate the position of various fatty acids attached to glycerol and the specificity of Lipolase-100T, hydrolysis of fish oil was carried out with Lipolase-100T derived from Aspergillus oryzae. The amounts of free fatty acids produced from triglyceride, 1,2(2,3)-diglyceride, 1,3-diglyceride, and 2-monoglyceride and conversion rates of 1,2(2,3)-diglyceride to 1,3-diglyceride and 2-monoglyceride to 1(3)-monoglyceride were also calculated. The ratio of 1,2-diglyceride content to 1,3-diglyceride was higher than 70 in the early period of hydrolysis. The fatty acid content of the glyceride mixture after 72 h of hydrolysis was compared with that of fish oil, and it was found that polyunsaturated fatty acids such as C16:4, C20:4 n-3, C20:5 n-3, C21:5 n-3, C22:5 n-3 and C22:6 n-3 were located in the 2-position of glycerol. Material balance of each component in the hydrolysis system was written to obtain a set of simultaneous linear equations. The theoretical quantity of free fatty acids produced from triglyceride, 1,2-diglyceride, 1,3-diglyceride, and monoglyceride, respectively, were calculated by solving the linear equation system. The conversion rate of 1,2(2,3)-diglyceride to 1,3-diglyceride and that of 2-monoglyceride to 1(3)-monoglyceride were also obtained. The results showed that the migration rate of 1,2(2,3)-diglyceride to 1,3-diglyceride was higher than the hydrolysis rate of 1,2(2,3)-diglyceride to 2-monoglyceride and the conversion rate of 2-monoglyceride to 1(3)-monoglyceride was extremely low.