• KOREAN JOURNAL OF CROP SCIENCE
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• v.31 no.2
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• pp.156-161
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• 1986

Silage productivity and resistance to rice black streaked dwarf virus (RSDV) of six Korean-improved and six US introduced corn genotypes were tested in the southern part of Korea. There was a negative correlation between culm length retarded by RBSDV and coefficients of variance of culm length. Frequency distribution of culm length could be classified as three genotypic groups according to the type of distribution and percentage of RBSDV diseased plants. There were negative correlations between percent RBSDV diseased plants at harvest and culm length, percent ear bearing plants, silage yield, or ear yield, but percent RBSDV diseased plants did not related to the ear/silage ratio and stover yield. Silage yield of Pioneer XCF38 was highest, but that of Suweon 89 and NC 6131 was lowest. However, there was not signi-ficant difference in silage yield among the remaining genotypes. Pioneer XCF38, Suweon 89, and Jinjuok were quite resistant to RBSDV, but Suweon 19, Kwangok, Hoengseongok, Jecheonok, and Pioneer 3424 were susceptible and NC 6131 was most susceptible to RBSDV. Although Jinjuok and Suweon 89 were resistant to RBSDV, silage yield was not high because of early senescence of leaves after silkillg.

• Proceedings of the Korean Society of Grassland Science Conference
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• 1999.06a
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• pp.78-79
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• 1999

미국으로부터 도입된 18종의 옥수수 품종과 국내품종 1종을 가지고 1997년에 경기 수원, 경북 경산 및 충남 천안에서 사일리지 생산성 비교 시험을 수행하였고, 특히 흑조위축병(RBSDV) 이병률이 옥수수의 가소화 영양소 총량(TDN)에 어느 정도 영향을 미치는가를 알아보기 위하여 일련의 조사를 수행하였다.(중략)

• Korean journal of applied entomology
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• v.16 no.2 s.31
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• pp.121-125
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• 1977

This is the first report on. rice black-streaked dwarf virus in Korea. The occurrence of this virus in Korea was confirmed by symptoms On rice Plants, Vector transmission and microscopic Observation in 1975. The smaller brown planthopper, Laodelphax striatellus FALLEN, transmits this virus which is spherical with a diameter of about 60 nm. Higher infection was observed in earlier transplanted rice with higher levels of fertilizer than in normal and standard cultivation fields.

• Journal of The Korean Society of Grassland and Forage Science
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• v.10 no.1
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• pp.42-47
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• 1990

Silage productivity of 7 corn and 3 sorghum hybrids was determined at two planting dates differing in rice black-streaked dwarf virus (RBSDV) infection rates in the southern part of Korea where RBSDV is prevalent. 1. Percent stand was similar between two planting dates, but that of corn hybrids (85.0-99.5 %) was higher compared with sorghum (59.8-82.3 %). Culm length of corn hybrids at April 23 planting was longer compared with May 20 planting, but that of sorghum hybrids was similar between two planting dates. 2. RBSDV infection rate of corn hybrids at April 23 planting was lower compared with May 20 planting, but sorghum was not infected at both planting dates. Among corn hybrids Suweon 19 was most severely infected, but Suweon 99 was least infected at both planting dates. 3. Percent ear bearing plants and earltotal dry matter (TDM) ratio of corn hybrids at April 23 planting was higher than those of May 20 planting. Among the corn hygrids percent ear beraring plants, ear/TDM ratio of Suweon 19 was lowest at both planting dates due to severe RBSDV infection. Ear/TDM ratio of sorghum hybrids was below 17.8 % due to sterility and partially bud damages. 4. Silage yield at April 23 planting was higher than that at May 20 planting and sorghum hybrids outyielded corn hybrids. Silage yield of Suweon 19 and Jinjuok was lowest due to severe RBSDV infection. 5. Crude protein was similar regardless planting dates, species, and varieties except the lowest P 931. Ether extract at April 23 planting was lower then that at May 20 and corn was lower compared with sorghum hybrids. Crude fiber and nitrogen free extracts(NFE) was similar between planting dates. Crude fiber of corn was lower, but NEF was higher compared with sorghum, but similar among hybrids in a species. 6. In vitro dry matter digestibility (IVDMD) at May 20 planting was higher than that of April 23 planting and corn was higher than sorghum hybrids. Digestible dry matter (DDM) of both corn and sorghum at April 23 planting was higher than that of May 20 planting. At April 23 planting DDM of all corn and sorghum hybrids was similar, but DDM of Suweon 19 and Jinjuok was lower than other corn and sorghum hybrids.

• 월간낙농육우
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• s.54
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• pp.27-32
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• 1986

• The Bimonthly Magazine for Agrochemicals and Plant Protection
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• v.6 no.5
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• pp.9-17
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• 1985

• The Bimonthly Magazine for Agrochemicals and Plant Protection
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• v.1 no.2
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• pp.48-52
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• 1980

• The Bimonthly Magazine for Agrochemicals and Plant Protection
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• v.3 no.7
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• pp.57-67
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• 1982

• KOREAN JOURNAL OF CROP SCIENCE
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• v.33 no.1
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• pp.74-80
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• 1988

Seasonal population changes in Laodelphax striatellus Fallen (small brown planthopper), percentage of rice black-streaked dwarf virus (RBSDV) viruliferous L. striatellus, and RBSDV infection of 11 corn hybrids were observed at various locations and years. The population size of L. striatellus was relatively small in the middle parts of Korea, but it was much greater in the southern areas. The population size of the first generation of adult L. striatellus emerged from late April to early May was similar or smaller compared with that of the second generation emerged in middle June in the middle parts of Korea. However, in the southern areas the population size of second generation was much greater than the first generation. The percentage of RBSDV viruliferous L. striatellus differed depending on the years, locations, and testing methods. The percentage of viruliferous vector was highest in southern plain areas and it tended to decrease with distance from the areas. The percentage of viruliferous vectors tested by enzyme-linked immunosorbent assay was higher than that tested by rice seedling test. The RBSDV infection rate of corn hybrids was highest at Daegu and ranged from 9 to 39% probably due to both a higher L. striatellus population and a higher percentage of viruliferous vectors. However, it was significantly lower in other areas and ranged from 0 to 13%.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.33 no.3
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• pp.229-235
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• 1988

Several agronomic characters, feed value, and mineral uptake of two corn hybrids infected by different degrees of rice black-streaked dwarf virus (RBSDV) were studied at the south-eastern part of RBSDV prevalent areas in Korea. Although both hybrids were infected with RBSDV by 100%. culm length of Suweon 19 was more severely reduced than that of Jinjuok and there were positive correlations between culm length and top dry weight of individual plants. The reduced culm length was largely due to the shortened length of upper five internodes in both hybrids and also due to the reduced number of internodes in Jinjuok. As culm length reduced, percent ear-bearing plants, average ear weight, and number of kernels per ear reduced significantly in both hybrids. The kernel weight of Suweon 19 decreased with reduced culm length, but that of Jinjuok was similar among the different culm lengths. However, as culm length decreased, crude protein and fiber in whole plants and N, P, K, Mg in culm ＋ leaf sheath increased, but nitrogen free extract in whole plant decreased. And crude fat in whole plant and N, P, K, Mg concentrations in leaf blades and ear were similar among the culm lengths.