• The Korean Journal of Mycology
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• v.6 no.1
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• pp.15-20
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• 1978

The purpose of the present study is to describe growth characteristics of seven species of Alternaria occur on naturally infected seeds, and to set up a guide line for quick identification of the species in connection with routine seed health testing. Host range and economic importance of each species are discussed and described with phototographs. The species studied are Alternaria tenuis, A. brassicicola, A. brassicae, A. raphani, A. dauci Alternaria radicina and A. sesami. Other resembling species are discussed in this paper.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.22 no.1
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• pp.11-15
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• 1977

Natural infection of purple stain seemed to be higher in early maturing lines comparing to late maturing group. It was positively correlated with length of the period from flowering to maturity and significantly associated with weather conditions during the maturing period.

• Korean journal of applied entomology
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• v.44 no.4 s.141
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• pp.299-306
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• 2005

Soybean seed injury was analyzed in the experiments that soybean pods were allowed to be sucked by adults of the bean bug, R. clavatus, and were picked with a specimen pin. While attack by the bean bug at podding stage of soybean caused the increase of empty pods and completely-undeveloped seeds, attack at full seed stage caused the increase of seeds wi distinct injury mark on seed-coat. The ratio of deformed seed was lower than those of injury-marked seed and undeveloped seed when attacked during all stages. In at full bloom stage hardly produced injury-marked seeds and deformed seeds. When the injured seeds were dyed with acid-fuchsine solution, stylet sheaths of R. clavatus formed on seed-coat were observed in 83% of undeveloped seeds formed under attack during podding stage and in 91% of injury-marked seeds formed during full seed stage. In pods injured with a specimen pin at full seed and full maturity stages, no healthy seeds could be obtained from the pods. And the more picked at full seed stage, the more deformed seeds were produced and the higher weight reduction of injury-marked seed occurred. However, pin-injury at full maturity stage didn't give rise to weight reduction of seeds.

• Korean journal of applied entomology
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• v.20 no.3 s.48
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• pp.146-150
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• 1981

Two rice cultivars infected by Gibberella fujikuroi, were tested to investigate the sequential change of disease development in the field conditions. In the preliminary test, the seeds of Nongbaek and an unknown cultivar showed 21 and $31.7\%$ infection by C. fuiikuroi. At the late stage of water nursery bed, some seedlings produced typical elongation symptom of bakanae disease and most of the leaves were dried up within a few days after transplanting. Out of the healthy looking seedlings, some plants also developed bakanae symptoms from middle June being two week after transplanting and the number was increased until middle September.

• Research in Plant Disease
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• v.10 no.1
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• pp.53-57
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• 2004

Cucumber green mottle mosaic virus (CGMMV) was a major pathogen of watermelon and had affected seriously to watermelon production in Korea. Rapid and sensitive detection method of CGMMV associated with bottle gourd (Lagenafia siceraria) seeds was developed by using RT-PCR in this study. A pair of primeri Wmfl and Wmrl, specific for CGMMV was designed from coat protein gene sequences of CGMMV-W and used for amplifying 420 bp product in RT-PCR. To simplify the virus extraction procedure and reduce an inhibitor from the extract for the RT-PCR, some methods using ethanol precipitation, double filtration, polyethylene glycol precipitation and phenol/chloroform/isoamyl alcohol extraction procedure were compared and the phenol/chloroform/isoamyl alcohol extraction procedure was selected by its enhanced sensitivity. This detection method using the selected extraction step and the primers for RT-PCR could reliably detect an infected level of one CGMMV-infested seed in 1,000 seeds. This rapid and sensitive RT-PCR assay provides auseful tool for the specific detection of CGMMV in bottle gourd seed samples containing high levels of back-ground inhibitors.

• Korean Journal of Environment and Ecology
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• v.35 no.6
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• pp.621-631
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• 2021

The purpose of this study is to survey and analyze acorn production and characteristics of the Quercus acuta Thunb. according to the need for information on seed supply and seedling cultivation during the restoration of warm broad-leaved forests. For the survey, a total of 30 seed traps with a surface area of 1 m² were set up, 3 in each of 10 quadrats (8 in Wando, 1 in Haenam, and 1 in Jindo). The acorns that fell in the seed trap at the end of each month were collected from August to December each year between 2013 to 2016. The collected acorns were then classified into sound, damaged, decayed, or empty grade, and the number of acorns produced was calculated. In the case of sound acorns, acorn traits, such as length, diameter and weight of acorns without cupule, were measured. Duncan's multiple tests of acorn production and characteristics were conducted for comparative analysis of the annual average values with the values by year, stand, month, and treatment plot. The annual number of acorn dropped into the seed traps in each quadrat from 2013 to 2016 was 5-350 acorns/3 m² in 2013, 17-551 acorns/3 m² in 2014, 5-454 acorns/3 m² in 2015, and 14-705 acorns/3 m² in 2016. There was a large difference in acorn production between the quadrats, presumably attributed to the difference in the amount of light received due to the density of trees in the square. Annual acorn production per area was 335,000 acorns/ha in 2013, 932,000 acorns/ha in 2014, 556,000 acorns/ha in 2015, and 1,037,000 acorns/ha in 2016. That was a sharp variation of acorn production in the two-year cycle. As the fluctuation in the production of Q. acuta showed simultaneity between stands, it is judged that Quercus acuta Thunb. had a clear cycle of fruitfulness and fruitiness between forest objects. September showed the biggest amount of fallen acorns and largest damage from insect pests, indicating that preventing early fall of acorns could increase the fruiting period and enable mass production of sound acorns. There was no significant difference between annual average acorn length in each region. In the case of the acorn diameter and weight, the average values of acorns from Haenam were significantly higher than those from Wando and Jindo. There was no significant difference in the average annual acorn characteristics by month, and the average annual acorn length, diameter, and weight in November were 19.72mm, 12.23mm, and 1.64g, respectively, the highest between August and November.

• 월간낙농육우
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• v.26 no.4 s.288
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• pp.100-103
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• 2006

협회사업 소식- 한 · 미 FTA 대응활동, 미국산쇠고기 수입재개 대응활동, 출산환경 분쟁사례 조사 실시, 제2회 회장단회의 개최, 우수축산물브랜드 육우부문 인증사업 추진, 식품안전처 신설 대응활동, 농림부 규제심사위원회 참석, 방역 담당책임자 간담회 참석, 우수농업경영체 추천, 축산현장 애로사항 모니터링 대상농가 추천, 구제역 특별방역대책기간 중 예방수칙 준수철저 요청, 에버케어 · 교보생명 업무협약 체결, 건전경마추진위원회활동/ 도지회 · 낙우회 소식 - 강원도지회 정기총회 개최, 연세우유연합회 총회 개최, 나주시지회 이취임식 및 낙농가족 한마음 축제 개최/ 총무사업부 소식 - 2006년도 봄재배용 목초 및 사료작물 종자 공급, 2006년도 가을재배용 목초 및 사료작물 종자 신청접수중, 조사료 공급, 송아지 지사제 공급

• KOREAN JOURNAL OF CROP SCIENCE
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• v.35 no.1
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• pp.44-52
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• 1990

In order to examine the possibility of seed propagation of jerusalem artichoke (Helianthus tuberosus L.) which has been propagated vegatatively so far, it was investigated the growth characteristics of seedlings and the biomass productivity by seed propagation in jerusalem artichoke. The results indicated that the seedlings from seeds exhibited the physiological dwarfing as a rosette habit. The physiological dwarfing as a rosette habit in jerusalem artichoke seedlings from seeds was a kind of appearance affected by photoperiod. This abnormal habit in seedlings from JA6 seeds during the growing period was persisted in short photoperiod of 10 hrs but was disappeared in long photoperiod of 14 hrs. In the condition of long photoperiod, seedlings from seeds grew normally and the average tuber yields obtained from seed propagation was finally 3.51 ton/10a, which can be the satisfying level to the use of seed propagation despite its complexity such as the needs of specific seedling time because it gives a high biomass productivity. This potential utilization of seed propagation in jerusalem artichoke can be basically applied to the collection or preservation of germ plasm and the improvement of jerusalem artichoke.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 2001.04b
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• pp.90-94
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• 2001

플러그 묘는 1990년대 초반에 도입된 이후로 육묘노력 절감과 균일한 묘의 이용 및 작물생산을 분업화 할 수 장점(Ito, 1992, Jeong, 1998)이 있기 때문에 많은 재배 농가가 이용하고 있다. 그러나 균일하고 건전한 묘를 생산해야 하는 공정육묘장의 측면에서는 개선해야할 문제점도 많다. 대표적인 문제점은 대량 생산을 위해 셀 수가 많은 트레이에 종자를 파종할 경우 시간의 경과에 따라 작물은 도장하게 된다는 점이다. (중략)

• Korean journal of applied entomology
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• v.18 no.3 s.40
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• pp.119-126
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• 1979

From the sample seeds of rice cultivar Palkoeng with the brown spot symptom, Helminthosporium oryzae was detected in $86\~92\%$ of hulls including empty glumes, lemma, palea, and rachilla in five to seven days of incubation. When the seeds were dehulled, the percentage detection decreased to $74\~83\%$ of pericarps. The fungus sporulated on whole surface of the seed and was detected within about ten cell layers deep of endosperm but not detected in embryo. Fusarium moniliforme was found in embryo as well as pericarp and endosperm. The frequency of F. roseum, Trichoconis padwickii, Curvularia spp., Atternaria tenuis, Cladosporium cladosporoides and Phoma sp. was less than three percent of hulls and pericarps. In seven days of incubation, $60\~87\%$ of the germinating seeds showed the symptom of H. oryzae while $13\~40\%$ were apparently healthy. This fungus in hilum of infected rice transmitted through pericarp to plumule shoot and radicle of the germinating seed.