• Journal of Sericultural and Entomological Science
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• v.50 no.2
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• pp.53-62
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• 2012

Silkworm larvae often suffer from viral infections causing heavy losses to the economy of silk industry. Insects exhibit both humoral and cellular immune responses that are effective against various pathohens like bacteria, fungi, protozoa, etc., but no insect immune responses is effective against viral infection. To obtain genes related to insect antiviral immunity from Bombyx mori, the cDNA library was constructed from B. mori nucleopolyhedrovirus (BmNPV)-infected B. mori. From the cDNA library, we selected 411 differentially expressed clones, and the 5' ends of the inserts were sequenced to generate ESTs. In this work, 135 unigenes were generated after the assembly of 411 differentially expressed clones ESTs. Of these 135 unigenes, we selected 109 antiviral response-related candidates except 26 clones that high similarity with genes derived from BmNPV. Among 109 unigenes, a total of 80% had significant matches to genes from other organisms in the database, wheres 20% of the unigenes had not matched in the database. Functional groups of these sequences with matches in database were constructed according to their putative biological function. Three largest categories were control of cellular oraganization (52%), metabolism (20%), and protein fate (10%). The genetic information reported in this study will provide more information about antiviral-related genes in silkworms.

• Korean Journal of Plant Resources
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• v.34 no.4
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• pp.257-262
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• 2021

This study was conducted to investigate the yield loss of soybean by initial density of Heterodera glycines in soil. A soybean cultivar named 'Cheongja5ho' was cultivated as test material in Dangjin city, Chungcheongnam-do, Korea. Each seed was planted with distance of 25 cm in 35 plots by initial density of egg of the cyst nematode on June 21^st, and allowed to harvest on November 12^st in 2019. As a results, the yield of soybean decreased sharply when as the initial density of eggs of cyst nematode increased. The initial density of eggs in soil affected largely on the decreased yields of the soybean by more than 20% in above 2,000 eggs, and 30% in above 6,000 eggs of the cyst. Beyond the 6,000 eggs, the yield loss was more slowly decreased compared with the above cases. Eggs of H. glycines are widely distributed in Korea, resulting in the serious soybean yield loss by H. glycines.

• Journal of Plant Biotechnology
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• v.49 no.1
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• pp.30-38
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• 2022

Solanum brevicaule is one of the tuber-bearing wild Solanum species. Because of its resistance to several important pathogens infecting potatoes during cultivation, it can be used for potato breeding. However, the fact that S. brevicaule used in this study has an EBN value of two causes the sexual reproduction barriers between the species and cultivated potatoes. In this study, specific markers for discriminating S. brevicaule from other Solanum species were developed on the basis of the results of sequence alignments with the whole chloroplast genomes of S. brevicaule and seven other Solanum species. The chloroplast genome of S. brevicaule was completed by next-generation sequencing technology described in other recent studies. The total sequence length of the chloroplast genome of S. brevicaule is 155,531 bp. Its structure and gene composition are similar to those of other Solanum species. Phylogenetic analysis revealed that S. brevicaule was closely grouped with other Solanum species. BLASTN search showed that its genome sequence had 99.99% and 99.89% identity with those of S. spegazzinii (MH021562) and S. kurtzianum (MH021495), respectively. Sequence alignment identified 27 SNPs that were specific to S. brevicaule. Thus, three PCR-based CAPS markers specific to S. brevicaule were developed on the basis of these SNPs. This study will facilitate in further studies on evolutionary and breeding aspects in Solanum species.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.27 no.1
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• pp.78-83
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• 1982

Seedling blight of sesame (Sesamum indicum L.) is one of the most serious diseases in Korea. This study was performed to control seedling blight in the field where sesame has been cultured for 4 years of Industrial Crop Division at the Crop Experiment Station. The pathogenic fungi of seedling blight which is known Fusarium oxysporum f. vasinfectium and Rhizoctonia solani was inoculated to the wheat media and it was spreaded on the experimental field in the concentration of 109 of wheat media mixed with 10g of fine soil. Seed sterilization was the most effective method for seedling blight control for two year experiment. Seed sterilant Benlate-T was highly effective for con trolling seedling blight with infection rate of 4% and yield of 40.7kg per 10a comparing to the control with infection rate of 96% and grain yield of 6.4kg per l0a, the other chemicals, Busan 30, Vitathiram, Captan showed good effect to control seedling blight, but less effect to the Benlate-T. The spraying treatments on leaf surface 25 days after sowing were not effective to seedling blight.

• Korean Journal of Breeding Science
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• v.42 no.3
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• pp.272-275
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• 2010

'Geumyoung' is a new early maturing rice cultivar developed from the cross between Sambaegbyeo and Iksan423/Sangju22 at Sangju Substation, NICS, RDA, Korea in 2009. It needs about 116 days from seedling to harvest in mid-mountainous areas. This cultivar has about 72 cm long culm and 19 cm long panicle, which are similar to Odaebyeo. It has higher panicle number per plant, medium to small grains and sometimes has a few awned spikelets. It shows tolerance to cold and resistance to blast but is susceptible to bacterial blight, virus diseases, and insects and pests. Milled rice of 'Geumyoeng' is translucent with non-glutinous endosperm and medium short grain. It has about 18.0% amylose and 6.6% protein content with good palatability of cooked rice. The milled rice yield of this cultivar was 5.53 MT/ha under standard fertilizer level of ordinary transplanting cultivation. 'Geumyong' would be adaptable for ordinary transplanting cultivation in the northern plains, and northern and southern mid-mountainous areas of South Korea.

• Korean Journal of Breeding Science
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• v.50 no.4
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• pp.504-509
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• 2018

A new black barley variety, "Heuksoojeongchal," was developed as a cross between "Keunalbori 1" and "Masankwamaek/Mortoni" at the National Institute of Crop Science, RDA in 2014. Heuksoojeongchal had a longer culm length (89 cm) and a later average heading date and maturity than Seodunchalbori. It also had a spike length of 5.0 cm, $543spikes/m^2$, and 54 grains/spike. The 1000-grain weight of Heuksoojeongchal (36.0 g) was heavier than that of Seodunchalbori. Heuksoojeongchal showed resistance to barley yellow mosaic virus (BaYMV). The yield potential of Heuksoojeongchal was approximately 7% higher than that of Seodunchalbori upland, but the average yield potential was similar in upland and paddy fields. Among the quality characteristics, the ${\beta}-glucan$ content (6.7%) was higher and the amylose content (5.5%) was lower than those of Seodunchalbori. The whiteness of the black barley was low, and its absorption rate and spreadability were similar to those of Seodunchalbori.

• Journal of Life Science
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• v.27 no.10
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• pp.1111-1120
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• 2017

This study was conducted to select pepper lines that were tolerant to excessive water injury among the pepper germplasm and investigate the genetic characteristics of those lines to contribute to the breeding of pepper cultivars with stable productivity in abnormal weather. Each of the tolerant and susceptible lines went through immersion treatment, and differentially expressed genes between them were analyzed. The tolerant line showed increased expression of the CA02g26670 gene, which is involved in the CONSTANS protein pathway and regulation of flowering by day length, but it exhibited decreased expressions of CA01g21450, CA01g22480, CA01g34470, CA02g00370 and CA02g00380. The susceptible line showed increased gene expressions of CA02g09720, CA02g21290, CA03g16520, CA07g 02110, and CA12g17910, which are involved in the inhibition of proteolytic enzyme activity, DNA binding, inhibition of cell wall-degrading enzyme, and inhibition of nodulin, respectively. Meanwhile the expressions of CA02g02820, CA03g21390, CA06g17700 and CA07g18230 decreased in the susceptible line, in relation to calcium-ion binding, high temperature, synthesis of phosphocholine and cold stress, respectively. The expressions of genes related to apoptosis and peroxidase increased, while that of CA02g16990, which functions as a nucleoside transporter, decreased in both the tolerant and susceptible lines. Based on the different gene expressions between the tolerant and susceptible lines, further studies are needed on breeding abiotic stress-tolerant lines.

• Journal of Korean Society of Forest Science
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• v.94 no.6
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• pp.402-409
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• 2005

This study was undertaken to compare and estimate the severity of pitch canker of individual trees of Pinus rigida and Pinus rigida ${\times}$ P. taeda in two seed orchards in Jeju island, in which the orchards have been damaged by the pitch canker for seven years. Wind-pollinated two-year-old seedlings of P. rigida and P. rigida ${\times}$ P. taeda, in which the seedlings of P. rigida ${\times}$ P. taeda were from seeds of phenotypically selected, uninfected(but untested) trees, were inoculated with the pathogenic fungus, Fusarium circinatum, isolated from P. rigida and P. thunbergii. The virulence of the isolates was also identified. Statistically significant difference was found in 'stem cankers'(SC; ${\chi}^2=7.76$, P=0.05) among 4 plantations of P. rigida ${\times}$ P. taeda of two seed orchards. P. rigida was higher in 'top kill' (TK) and 'branch tip symptoms' (BT) than those of P. rigida ${\times}$ P. taeda. In artificial inoculation tests, mortality of the seedlings from the resistant candidates was 14% higher than that of the seedlings from the susceptible candidates. This result may becaused by unknown pollen trees and/or candidate tree selection based only on phenotype. Two of five fungal isolates, C-6-L(9) and C-6-L(19), showed significantly higher mortality (68% and 60%, respectively) than others, suggesting that these isolates can be used as virulent isolates for a mass artificial inoculation. Resistance candidate seedlings that were selected from this study can be utilized as useful materials for fundamental studies of genetics and biochemistry to breed resistance varieties to pitch canker.

• Journal of The Korean Society of Grassland and Forage Science
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• v.28 no.3
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• pp.221-228
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• 2008

This experiment was carried out to investigate the actual outbreak status of rice black-streaked dwarf virus (RBSDV) disease in forage corn for securing the basic data to control of the disease all over the country from 2006 to 2007. Outbreak of the disease showed a wide difference according to regions and was severe in Icheon, Gochang, Kimje, Youngkwang, Kimchun, Youngju, Cheonan, and Boroung provinces in Korea. Outbreak rate of the disease was effected by planting time of forage corn. Disease rate was lower in corns planted from Apr. 26 to May 15 than in those of planted from April 10 to 25 or after May 31. The corn fields planted from April 26 to May 15 showed lower disease rate than that of planted from April 10 to 25 or after May 31. Also the outbreak rate of the disease was some difference according to corn varieties but was not genuinely resistant varieties to RBSDV. Dry matter yield of forage corn was significantly decreased depending on disease rate, and was highly negative correlation to disease rate. The forage corn infected with RBSDV was lower 3.2%, 3.6% and 12% in IVDMD, TDN, and RFV, and higher 3.7% and 4.5% in NDF and ADF than those of the healthy plant, respectively.

• 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 %.