• Journal of The Korean Society of Grassland and Forage Science
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• v.19 no.3
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• pp.281-290
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• 1999

The bacterial isopentenyl transferase (ipt) gene involved in cytokinin biosynthesis was fused with 35S promoter of cauliflower mosaic virus (CaMV) and introduced into tobacco plants (Nicotiana tabacum L. cv. Samsun) via Agrobacterium-mediated transformation. As expected, ipt gene was constitutively expressed in all tissues of transgenic plants. Several primary transgenic plants were obtained that expressed different level of transcripts for ipt gene. Three of transgenic plants with different expression level of ipt gene were selected and selfed to obtain homozygous line for further analysis. A number of interesting phenotypic changes such as viviparous leaves, delayed senescence, larger axillary shoots, an abundance of tiny shoots at the apex and a release of lateral buds, were observed in transgenic plants. Chlorophyll content was 1.5- t.o 4-fold higher in transgenic plants as compared with non-transformed plants. These results indicate that the cytokinin synthesized in transgenic plants could improve forage crop yield by delay of leaf senescence and increase of leaf number.

• Korean journal of applied entomology
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• v.13 no.1 s.18
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• pp.25-31
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• 1974

This survey was aimed to accumulate basic data of aphid population at the Horticultural Experiment Station at Suweon. The yellow pan traps were setted at five locations (Fig.1.), and ran from May 1 to October 31. 1970. About one hundred and twenty species of aphids were trapped, including 24 species of plant vims vectors. Of these, dominant species were as follows: (Asterisk shows virus vector) Aphid species No. of catches * Aphis spiraecola PATCH 2,635, * Aphis craccivora KOCH 2,377, * Myzus persicae SULXER 2,111, Capitophorus hippophaes javanicus H.R. LAMBERS 2,051, Anoecia fulviabdominalis SASAKI 1,480, * Aphis gossypii GLOVER 867, * Macrosiphum avenae FABRICIUS 859, Cervaphis quercus TAKAHASHI 692, * Lipaphis erysimi KALTENBACH 645, Pleotrichophorus chrysanthemi THEOBALD 489, The above 10 species consisted $76.5\%$ of total catches and the 24 vector species consisted $55.5\%$. The curve of the seasonal occurrence of flying aphids at Horticultural Experiment Station shows bimodal, typical for the temperate region. The total number of trapped aphids at the Station from May to September, 1970, were less than that of average yearly catches at the College of Agriculture from 1967 to 1970. Thi, low numbers at Horticultural Experiment Station may attribute to the frequent spraying of insecticides from Spring to Summer on growing crops there. But the aphids population increase suddenly in the middle of October. This might be resulted from cease of insecticide applications and migration of aphids from summer host to winter host plants.

• Journal of the Korean Association of Geographic Information Studies
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• v.18 no.3
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• pp.89-101
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• 2015

Outbreaks of highly pathogenic avian influenza(HPAI) subtype H5N8 have occurred in Korea, January 2014 and it continued more than a year until 2015. And more than 5 million heads of poultry hads been damaged in 196 farms until May 2014. So, we studied the spatial, temporal and spatio-temporal patterns of the HPAI epidemics for understanding the propagation and diffusion characteristics of the 2014 HPAI. The results are expressed using GIS. Throughout the study period three epidemic waves occurred over the time. And outbreaks made three clusters in space. First spatial cluster is adjacent areas of province of Chungcheongbuk-do, Chungcheongnam-do and Gyeonggi -do. Second is Jeonlabuk-do Gomso Bay area. And the last is Naju and Yeongam in Jeollanam-do. Also, most of spatio-temporal clusters were formed in spatially high clustered areas. Especially, in Gomso Bay area space density and spatio-temporal density were concurrent. It means that the effective prevention activity for HPAI was carried out. But there are some exceptional areas such as Chungcheongbuk-do, Chungcheongnam-do, Gyeonggi-do adjacent area. In these areas the outbreak density was high in space but the spatio-temporal cluster was not formed. It means that the HPAI virus was continuing inflow over a long period.

• Korean journal of applied entomology
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• v.5_6
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• pp.47-54
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• 1968

In order to develop an effective control measure for the rice stripe disease, methods of testing for resistance and selection of resistant varieties among the leading varieties were investigated. For use as a parent in breeding for resistant variety to the disease, total of 410 rice varieties were tested. 1. Disease occurrence was higher at group inoculation than that of individual inoculation in comparing the inoculation methods. 2. In both methods, Lacrose responded susceptible; Zenith and St. No. 1 resistant, and the rest moderate. 3. Suseptible symptom type A was prevalant among the susceptible varieties, while resistant symptom type C was abundant among the resistant varieties, There was no difference between the inoculation methods. 4. 410 rice varieties tested could he divided into 3 groups as susceptible (21 varieties), moderate (377 varieties) and resistant (12 varieties). Resistant varieties wers St. No. 1 and 2, Shin-2, Gulfrose Bonnet, Arkrose, Sun Bonnet, Zenith, Yeechunchilichal, Norm-24, Opaikjoke, Yangchubatchal and Nonglimana-1, Nams-97,-149, -159, -216. -265, Iri-243, -265, Kanchuk -5, -7, -8, -10, -41, -43, -47, -50, Suwon-56, -77, Norin-22, Cod-4. Lacrose and Chukna were susceptible. 5. There was slight differance in the disease occurrence in regard to maturing period. However late varieties seem to be more resistant than early or medium varieties. The medium varieties seem to be susceptible. Most of the introduced varieties from foreign countries and the upland cultivated varieties were resistant. 6 Among the leading varieties, Shin-2 in Kangwon-Do was resistant, Kosi in Choongchung-Do, was susceptible, aad the others were moderate.

• Horticultural Science & Technology
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• v.34 no.3
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• pp.355-362
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• 2016

This study was carried out to investigate the effects of rain-shelter types on growth, and fruit quality of red pepper (Capsicum annuum, 'Kemmaru') cultured in paddy. Applied rain-shelter types were outfield (control), simple rain-shelter plastic house with 2 rows (2R), simple rain-shelter plastic house with 4 rows (4R), and perfect plastic house (House). The plant height was the highest in Houses treatment. There was no difference in leaf length and width among the rain-shelter treatments. The fresh and dry weight of red pepper was high in order of House > 4R > 2R > Control. The ASTA value is irregular tendency among the treatments. Hunter's color value 'a' and 'b' was not different from among the treatments. Phytophthora blight, powdery mildew, bacterial spot were not occurred in all of treatments, and Anthracnose was only occurred in control. Mite, Microcephalothrips abdominalis, and Bemisia tabaci were not occurred in all of treatments, and aphid, Helicoverpa assulta, and virus were occurred all of treatments as same degree. Our results will provide rain-shelter cultivation of red pepper can be increase dry yield and decrease disease and insects.

• Korean Journal of Breeding Science
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• v.40 no.3
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• pp.295-298
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• 2008

"Dongjin2" is a new japonica rice cultivar developed from the cross between Milyang165 with short culm and lodging resistance and $F_1$ plant of Iksan438, HR14018-B-1-1 and Iksan435 with high palatability at Honam Agricultural Research Institute (HARI), NICS, RDA in 2005. This cultivar has short grain shape and about 143 days growth duration from direct seeding to harvesting under Korean climate condition. The milled kernels of "Dongjin2" is translucent with non-glutinous endosperm. It has about 19.3% of amylose content and better palatability of cooked rice compared with "Nampyeongbyeo". This cultivar shows high resistance reaction to the bacterial blight pathogene race from $K_1$ to $K_3$, blast and stripe virus but susceptible to insect pests. "Dongjin2" yields about 5.71 and 5.74 MT/ha under the wet direct seeding and the transplanting at standard fertilizer level. "Dongjin2" would be adaptable for the southern plain area of Korea.

• Korean Journal of Breeding Science
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• v.43 no.6
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• pp.538-542
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• 2011

A new malting barley variety, 'Baegho', was developed from a cross between Azuma Golden and Nishinochikara in 1998. An elite line, YMB2139-2B-1-10-2, was selected in 2005 and designated as Milyang137. It showed good agronomic performance in the regional adaptation yield trials (RYT) from 2006 to 2008 and was released with the name of 'Baegho' having high yielding and BaYMV and powdery mildew resistance. The average heading and maturing dates of 'Baegho' were April 21 and May 28, which were 3 and 2 day later than those of Hopum, check variety, at the RYT, respectively. 'Baegho' has shoter culm length (78 cm), more spikes ($1,062per\;m^2$) and heavier 1,000 grain weight (40.7 g) than those of Hopum, respectively. 'Baegho' is resistant to domestic BaYMV strains I, III and IV and powdery mildew at Iksan. In growth habit, 'Baegho' is close to type (IV) that is distinguished from other Korean malting barley cultivars, which could tolerant to premature heading damage that is major concern for the practice of the malting barley cropping. The yield potential of 'Baegho' in the RYT was about 5.57 MT/ha, which is about 13% higher than those of Hopum. This variety has good malting quality in grain and malting analysis showed better 1,000 grain weight, husk rate, diastatic power than those of Hopum. 'Baegho' applied for protection of new varieties of plant in 2009.

• Korean Journal of Breeding Science
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• v.50 no.4
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• pp.485-489
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• 2018

A mungbean cultivar "Munpyeong" (Vigna radiata (L.) Wilczek) was derived as a cross between "Keumseong" and "IT163157" at the Jeollanamdo Agricultural Research and Extension Services (JARES) in 2013. "Munpyeong" has an erect growth habit, heart leaflet, green hypocotyls, black and straight pods when matured, and a dull green seed surface. The stem length of "Munpyeong" was 60 cm, which was 6 cm shorter than that of the control cultivar "Owool." The pod number per plant was 25, which was 3 more than that of the control cultivar. The 1000 seed weight of "Munpyeong" was 45 g, which was 4 g lighter than that of the control cultivar "Owool." Its field resistance to mungbean mottle virus, cercospora leaf spot, and powdery mildew are similar to the control cultivar, whereas its field resistance to lodging was slightly stronger. The hard seed rate of "Munpyeong" was 3.2%, which was similar to that of the control cultivar. The sprout yield ratio was 7.54 times, which was 9% more than that of the control cultivar. The average yield of "Munpyeong" was 1.93 ton/㏊, which was 21% more than that of the control cultivar "Owool" (Cultivar registration number: 5878).

• Plant Breeding and Biotechnology
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• v.6 no.4
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• pp.404-412
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• 2018

The influenza neuraminidase (NA, E.C. 3.2.1.18), an antiviral, has been the target of high pharmaceutical companies due to its essential role in viral replication cycle. Perilla frutescens (P. frutescens) is used in traditional Chinese medicine for various diseases, such as cold due to wind-cold, headache and cough. In this context, four major polyphenolic compounds including rosmarinic acid-3-O-glucoside (1), rosmarinic acid (2), luteolin (3), and apigenin (4) isolated from P. frutescens were evaluated for their inhibitory effect on recombinant virus H1N1 neuraminidase (rvH1N1 NA). Among the test compounds, rosmarinic acid and luteolin inhibited the rvH1N1 NA with an $IC_{50}$ of 46.7 and $8.4{\mu}M$, respectively. The inhibition kinetics analyzed by the Dixon plots indicated that rosmarinic acid and luteolin were noncompetitive inhibitors and that the inhibition constant, $K_I$, was established as 43.9 and $14.3{\mu}M$, respectively. In addition, 578 genetically diverse accessions and 39 cultivars of P. frutescens were analyzed using HPLC to characterize the diversity of polyphenolic composition and concentration. The individual and total compositions exhibited significant difference (P < 0.05), especially rosmarinic acid which was detected as the predominant metabolite in all accessions (58.8%) and cultivars (62.8%). Yeupsil and Sangback cultivars exhibited the highest rosmarinic acid ($3,393.5{\mu}g/g$) and luteolin ($383.3{\mu}g/g$) content respectively. YCPL177-2 with the high concentration ($889.8{\mu}g/g$) of luteolin may be used as a genetic resource for breeding elite cultivars.

• Korean Journal of Breeding Science
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• v.50 no.4
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• pp.522-528
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• 2018

Saemimyeon, a Tongil type, medium-late maturing rice variety, is especially used for preparing rice noodles. Its high amylose content was developed to fit market demands and to be affordable for rice processing industries. One of the high yielding lines, Milyang181 (Hanareum), was used in the final three-way cross of $IR50^*2$/YR18241-B-B-115-1-1 for yield improvement and cultivation stabilization, including disease resistance. YR24235-10-1-3, a high yielding and compact plant type, was selected and named Milyang278 after yield test at NICS (RDA, Miryang) in 2010. It was subjected to regional yield test at six sites in the middle and southern plain areas of South Korea. Saemimyeon heading occurs on August 12 and is a mid-late maturing cultivar, with resistance to leaf blast, rice stripe virus, and bacterial blight (K1-K3a), but it is susceptible to major diseases and insect pest infestation. Saemimyeon showed a high amylose content of 26.7%, with a relatively low KOH digestion value of 3.5, which are key factors in rice noodles and pasta processing. In the local adaptability tests, the yield of Saemimyeon was 7.08 MT/ha-an increase of approximately 106% compared to that of Dasan. Thus, Saemimyeon is suitable for cultivation in the southern and middle plain areas of South Korea.