• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.114.2-115
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• 2003

Rice stripe virus causes severe damage to rice in Korea, Japan and China. RSV is a type member of the tenuivirus group and transmitted by the small brown planthopper, Laodeiphax striatellus, in a persistant manner. Until now, occurrence of RSV is limited in of southern part of Korea. But recently occurrence of RSV is increasing and spreading in central part of Korea including Chungcheong and Kyonggi province. So we analyzed recent occurrence trend of RSV which is increased and cloned and sequenced coat protein gene for isolating of RSV strain. Infected rice of each species(Ilpumbyeo, Sindongjinbyeo, Keumobyeo-2, Dongjinbyeo, Jongnambyeo, Samcheonbyeo, etc.)is collected, we extracted total RNA from infected leaves and detected RSV viral RNA by reverse transcription(RT)-PCR using specific primer of coat protein gene. The result of RT-PCR, we observed specific band. We already cloned cDNA from the band, is analyzing sequence variety and homology of each species.

• Research in Plant Disease
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• v.14 no.3
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• pp.210-213
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• 2008

The occurrence of Rice stripe virus (RSV) has been confirmed in some parts of South Korea. In the current year, this was observed to be limited in the double cropping zones of the southern region. Earlier, RSV occurred largely in the west coast regions of the country, particularly in Gangwha, Gyeonggi-do in 2001; and Buan, Jeollabuk-do and Seocheon, Chungcheongnam-do in 2007. This study was carried out to determine the nationwide extent of RSV occurrence by investigating RSV infestations in different latitudes and altitudes. Result revealed a recent reported occurrence of RSV in the southern region (Milyang, latitude $35^{\circ}$), a reported occurrence in the northern region (Cheolwon, latitude $38^{\circ}$) in 2005, and in the middle northern region of the east coast (Goseon, latitude $38^{\circ}$) as newly confirmed from this investigation. Results also confirmed the occurrence of RSV in a wide range of altitude from the plains (Milyang, 17 m altitude) to the alpine regions (Jinbu, 576 m) including the middle mountains (Sangju, altitude 285 m). The RSV occurrence in Jinbu in the alpine region and at Goseong and most of the northern end regions were confirmed only this year. The results of the present study confirmed that RSV is a fast-spreading disease in rice plant cultivation regions of the entire country.

• Research in Plant Disease
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• v.10 no.1
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• pp.30-33
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• 2004

Until now, occurrence of rice stripe virus (RSV) is limitted in southern part of Korea. However, recently the occurrence of RSV is increased and spreaded in central part of Korea including Chungcheong and Kyonggi province. It is very difficult to distinguish RSV symptoms on virus symptom physiological damage of rice. We detected RSV viral RNA from infected rice and its insect vector Laodelphax striatellus using specific primer of RSV-polymerase and coat protein gene with reverse transcription (RT)-PCR. The result of RT-PCR, we observed specific band including RSV-polymerase (1,,023 bp) and CP (969 bp) in both host of rice and insect vector.

• Research in Plant Disease
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• v.18 no.4
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• pp.402-405
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• 2012

We surveyed the occurrence of Rice stripe virus (RSV) disease in 672 fields from 29 rice representative area in July 2012 as nationwide survey for RSV occurrence since 2008. We confirmed occurrence of virus disease in 18 areas, in west coast region including Secheon, Taean, Buwan and Cheorwon. RSV incidence rates of plant in Sacheon and Buan were less than 0.01% and 0.15%, respectively, showing similar rate with the nationwide survey carried out in 2008, whereas incidence rate of field declined from 19.9% in 2008 to 4.9% in 2012. Earlier, RSV occurred largely across the southern region of Korea. In 2001, RSV disease was found in Gangwha and Gyeonggi-do, the northern region of Korea. In 2007, RSV appeared in west coast; Buan in Jeollabuk-do and Seocheon in Choongnam-do. After migration of the vector, small brown plant hopper, from China in 2009, RSV is becoming a pandemic.

• Research in Plant Disease
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• v.16 no.2
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• pp.109-114
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• 2010

The occurrence factors of Rice stripe virus (RSV) in Chungcheongbukdo were analyzed by investigating the viruliferous insect rate (VIR) of overwintered small brown plant hopper (SBPH), the population density of SBPH, the infection rate of natural host plants, and the occurrence rate of RSV on rice paddy fields at the 3 areas of Cheongwon, Jincheon, and Boeun in 2008 and 2009. The average VIR of overwintered SBPH was 0.0% in 2008 and 1.1% in 2009. From SBPH collected on early June in 2009, VIR was higher as 1.4% at Jincheon and 4.2% at Boeun than those of overwintered SBPH, and this higher VIR might relate stronlgy with the adult population of SBPH immigrated from China. The populations of SBPH at Cheongwon, Jincheon and Boeun in 2008 were 3.8, 7.5 and 20.8 Head/$m^2$, respectively. However, those of Cheongwon and Jincheon increased up to about two folds as 8.4 and 13.1 in 2009. No RSV was detected on the natural host plants including barley. The factors involved in RSV occurrence were affected negatively by the low VIR of overwintered SBPH, the low population of overwintered SBPH, the low infection rate of RSV on the natural host plants, and the clean cultivation environment in Chungcheongbukdo.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.140.2-141
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• 2003

Among over-wintering small brown planthoppers, population of the rice stripe virus (RSV)-viruliferous insects was surveyed throughout the country in late April of 2003 by using DAS-ELISA. Averaged population of the RSV-viruliferous insects in this year was 2.1％, which was lower than that of last year of 3.7％. However, the insect population in Seoul, Incheon and Kyeonggi areas were relatively high showing 6.7％, 6.2％ and 2.6％, respectively. Based on the survey results, it was expected that overall occurrence of RSV on rice could be decreased in this year, except certain areas. Ovarial transmission rate of RSV by the insects on diseased rice samples collected from 10 areas ranged from 22.2％ to 77.8％. Among 35 graminous weed species collected from rice fields in Ganghwa and Kimpo in 2002 and 2003, common reed and formosens were found to be infected by RSV. The result indicates that those weeds are potential alternative natural hosts of the RSV Further studies on ecological and pathological impacts of the alternative natural host of RSV are being processed.

• Research in Plant Disease
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• v.14 no.1
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• pp.1-9
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• 2008

The severe damage induced by the important viruses of Rice stripe virus (RSV), Cucumber green mottle mosaic virus (CGMMV), Melon necrotic spot virus (MNSV), Tomato spotted wilt virus (TSWV) and Tomato bushy stunt virus (TBSV) was described on major crops in Korea. In 2007, the plot incidence rate of RSV was 100% on the precocious rice cultivars at the Western coastal provinces of Gyeonggido, Chungcheongnamdo, Jellabugdo and Jellanamdo, and Jejudo. RSV occurred in 2,441 ha with incidence rate of 70% over at 5 areas of Seocheon, Seosan, Boryung, Hongsung and Buyou in Chungcheongnamdo. At 4 areas of Buan, Gimje, Gunsan and Gochang in Jellabukdo, RSV occurred in 2.016 ha. CGMMV occurred on watermelon in 4.6 ha at Cheongyang area, and its outbreak was also 890 ha on oriental melon for 120 farmers with the incidence area of 23% against total cultivation areas of Seongju. MNSV was recorded firstly on watermelon in 2006 at Andong and it spread to 3 areas of Hapcheon, Gochang and Yanggu. TSWV occurred firstly at Danggin in Chungcheongnamdo in 2005. TSWV in 2006 spread to 6 areas; Taian, Hongsung and Seosan in Chungcheongnando, Namwon in Jellabukdo, and Sunchon and Kwangju in Jellanamdo. In 2007, TSWV covered 17 areas of western and southern parts; the 5 area including Taian in Chungcheongnamdo, Kwangju in Jellanamdo, Bucheon in Gyunggido, and so forth. TBSV was described firstly on table tomato at Sacheon in Kyungsangnamdo in 2004. TBSV occurred on cherry tomato at Chungju in 2006 and on table tomato at Busan area.

• Research in Plant Disease
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• v.17 no.3
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• pp.351-357
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• 2011

Occurrence of Rice stripe virus (RSV) was investigated in Jeonnam province from 2008 to 2011. Incidence of RSV was surveyed in paddy fields during growth stage. In western and southern coast parts of 5 districts, Jindo, Wando, Shinan, Haenam and Muan, rice was severely damaged by RSV from 2008 to 2009. But, RSV didn't almost occur in 2010. Viruliferous ratio (VIR) of RSV from overwintered small brown plant hopper (SBPH, Laodelphax striatellus) showed 4.7%, 11.3%, 8.7%, and 2.8% from 2008 to 2011. It was highly recorded in Jindo, Wando, and Shinan of southwestern area. SBPH was collected by sucking machine at 1 $m^2$ with 3 replications per paddy field in March. The density of SBPH was high on March, but low on April in non-cultivated barley field from winter to spring. Farmer's plowing this season assumed to be a cause of SBPH density decrease. The number of SBPH was 7.7, 5.4, and 4.0 per $m^2$ during three years, respectively.

• Korean Journal Plant Pathology
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• v.1 no.2
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• pp.109-114
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• 1985

The experiments were conducted to clarify the influence of transplanting date on the occurrence of rice virus in field condition of 1984. The rate of RBSDV (rice black-slreaked dwarf virus) viruliferous vector, smaller brown planthopper (Laodelphax striatellus Fallen), was shown to be $13.6\%$ at the 2nd adult and that of rice stripe virus (RSV) viruliferous was $6.7\%$ at the 2nd adult. The vector in the field was begun to come from May 29, the maximum densities were 19.6 insects per hill on June 13 in cultivar Chucheongbyeo, 19.3 in Nagdongbyeo, 7.4 in Cheongcheongbyeo and 4.9 in Samgangoyes. The number of vectors per hill was inclined to increase by early transplanting. Although the infection of rice virus in nursery bed was not recognized until May 30 transplanting, the nursery infection could be seen from June 10 transplanting. The highest rate of nursery infection with RSV was $4.1\%$ at June 10 transplanting plot, and that of RBSDV was $14.2\%$at June 20 trans planting plot. The infection of rice virus in paddy field was the highest at May 20 transplanting plot, the lowest at July 10 plot. The earlier transplanting, the more severe occurrence of rice viruses. Occurrence of infected plants with RBSDV was shown to increase more rapidly at May 20 and May 30 planting plot than May 10 plots. However, the occurrence of infected plant with RSV was more rapid at May 10 transplanting plot than May 20 and 30.

• Clinical and Experimental Pediatrics
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• v.52 no.3
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• pp.269-276
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• 2009

Viruses are the most common cause of lower respiratory tract infections (LRTIs) in infants and young children and are a major public health problem in this age group. Viruses were identified in 54.9-70.4% of hospitalized infants and children with LRTIs in Korea. The viral pathogens identified included respiratory syncytial virus (RSV) A and RSV B, influenza (Inf) A, Inf B, parainfluenza (PIV)1, PIV2, human bocavirus (hBoV), human rhinovirus (hRV), adenovirus (ADV), human metapneumovirus (hMPV), human coronavirus (hCoV)-OC 43, hCoV-229E, hCoV-NL63, hCoV-HKU1, and human enterovirus (hEV). Coinfections with ${\geq}$2 viruses were observed in 11.5-22.8% of children. The occurrence of LRTIs was the highest in the first year of life. The specific viruses are frequently associated with specific clinical syndromes of LRTIs. LRTIs caused by RSV were predominant among younger infants. hRV accounted for a larger proportion of LRTIs in young infants than ADV and hBoV. hMPV was frequently detected in children >24 months old. The number of hMPV infections peaked between February and May, whereas hRV was detected throughout the year. Thus far, hCoV is a less common respiratory pathogen in cases of ALRI and URI in Korean children.