• Research in Plant Disease
• /
• v.18 no.3
• /
• pp.245-249
• /
• 2012

The small brown planthopper (Laodelphax striatellus) is one of the most important rice pests in Republic of Korea because it damages rice plants not only by sap-sucking but also by transmitting Rice stripe virus (RSV). Outbreaks of RSV are closely related to outbreaks of the small brown planthopper (SBPH). Therefore, it is very important to control SBPH for the management of RSV. Mass-migrating SBPH collected by aerial net traps in June 2011 at Taeanup, Geunheungmyon and Gonammyon in Taeangun were examined for virus carrier status and effects of the pesticide, 'Myungtaja', on the control of RSV. Among 1,217 SBPH trapped, about 7.7% were detected as RSV positive and 4.4% were positive for Rice black streak dwarf virus (RBSDV) by RT-PCR. After the mass migration, pesticide 'Myungtaja' was sprayed once or twice on rice fields and compared to untreated fields. The incidence of RSV was not affected by the frequency of spraying 'Myungtaja' but was influenced by the time of pesticide treatment. Myungtaja' treatment within 5-7 days after mass migration resulted in the most efficient RSV control, resulting in RSV incidence decreased by 87.6% compared to the control. Therefore, we conclude that pesticide spraying for RSV control was most effective when it was done within 5-7 days after mass migration.

• Korean journal of applied entomology
• /
• v.26 no.1 s.70
• /
• pp.9-12
• /
• 1987

The control effect of three systemic insecticides on the brown planthopper; carbofuran 3G, disyston 3G, and omethoate 50% EC, which have been used to control of the insect pests on rice crop in its early growing season, were evaluated. Soil incorporation and water broadcasting methods before transplanation were used for carbofuran and disyston, and omethoate was applied as foliar spray 6 days after transplanation. Ten pairs of newly emerged adults were inoculated on June 11, 21, July 2, 11, and 25. The number of the brown planthoppers on the rice plane were examined by means of direct reading. The three insecticides were effective for about ten days regardless of application methods, thereafter, fail to control of the insects except carbofuran. By means of soil incorporation, carbofuran could control the insects effectively for 45 days or longer, and it seemed to be able to control the progeny of the migrated brown planthopper until middle or late June.

• Korean journal of applied entomology
• /
• v.19 no.1 s.42
• /
• pp.45-50
• /
• 1980

The control effects of four systemic insecticides $Disyston^{(R)}$ (disulfoton) 5G, $Temik^{(R)}$ (aldicarb) 15G, $Ortran^{(R)}$ (acephate) 5G and $Curaterr^{(R)}$ (carbofuran) 3G, on small brown planthopper, Laodetphax striatellus (fallen), were studied by applying them in the furrow of spring barley field. Two different application times; April 19 and 25, and three different dosage rates were used. The results are as follows: 1. No significant difference in the mortalities among the developmental stages were observed with the treated barley on April 25, when various life stages had infested on the cutting of the treated barley in the laboratory. The residual periods were 19 days for Disyston and 31 days for Temik. 2. With field experiments, highly effective control effects were obtained with Disyston and Temik. The residual period was longer with the treatment on April 19 than with those on April 25 for Disyston, while they were reverse for Temik. 3. The effective doses were 2kg/10a for Disyston, while the effectiveness lasted more than 40days with dose of 1kg/10a for Temik. 4. From above results, Disyston and Temik could effectively reduce the population of small brown planthopper in the barley field, which is the effective reproductive sources of the population in the rice field.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.56 no.2
• /
• pp.167-176
• /
• 2011

Brown planthopper (BPH) is a serious insect pest of rice crop throughout rice growing countries, and yield loss due to its infection can be up to 60%. This study aimed to evaluate efficiency of molecular markers for screening BPH resistance accessions among 86 aromatic rice germplasm Eighty-six accessions of aromatic rice germplasm included two accessions of Tongil type (bred in Korea), 28 accessions of japonica type and 56 accessions of indica type. We applied eight STS markers (pBPH9, pBPH19, pBPH20, pBPH21, AJ09-b, RG457L, RG457B, and 7312.T4A) which were linked to four of BPH resistance genes, Bph1, Bph13(t), Bph10, and Bph18(t) respectively. One japonica type accession, 415XIr352, and six indica type accessions possessed one or four positive bands when tested with four STS markers linked to Bph1 gene. One indica type aromatic rice, Basmati9-93, showed the target bands linked to the Bph10 gene. The other accessions did not show same fragments as the respective resistant lines. Bph13(t) is the most widely introduced resistance gene and only one accession showed positive bands implying that this accession might harbor Bph10 and Bph18(t) genes. Three aromatic accessions, Domsiah, Khao Dawk Mali 105 and 415XIr352 showed gene pyramiding of Bph1 and Bph13(t). Two indica aromatic rice, Ds 20 and Basmati 9-93, possessed at least two BPH resistance genes, Bph1, Bph18(t) and Bph13(t), Bph18(t), respectively. These results indicates that aromatic rice germplasm have narrow diversities of BPR resistance genes.

• The Korean Journal of Pesticide Science
• /
• v.15 no.4
• /
• pp.490-494
• /
• 2011

Rice stripe virus (RSV) has been the main viral disease of rice plant in western coastal region of Korea since 2000. The control of the vector insect, small brown planthopper (Laodelphax striatellus), is the most effective management method of the persistently-transmitted viral disease. Thus, ecological study between RSV and the vector insect was needed and investigated in order to make effective control plan, especially about study on the feeding and transmission of the virus by the vector insect. Each larval stage of vector insect differed in vector competence; larvae over 4th stage were shown as higher transmission after feeding on RSV-infected rice plant. These 4th and 5th larvae had higher transmission rates, 69.2% and 67.9% respectively, than 44.8% of the adult stage. The vector competence, however, was changed according to temperature; the highest transmission rate was 93.3% on $30^{\circ}C$ in comparison to 70.6% on $25^{\circ}C$ and 43.8% on $20^{\circ}C$.

• Korean journal of applied entomology
• /
• v.31 no.4
• /
• pp.543-550
• /
• 1992

Residual and biological effects of buprofezin(25% WP) on the larvae of the brown planthopper(BPH), Ni/aparvata /ugens SUlI, were studied by pot experiments. Residual lethal effects on the 2nd instar larvae lasted significantly long, and were higher with application rates. The rate of 17.50 g a.i./10a showed ca. 90% mortality even on 35 days after treatment (OAT). $RLT_{90}$ and $RLT_{50}$(residual lethal time that can show 90% and 50% mortality, respectively) with rates of 5.78-11.50 g a.i./lOa were 9.0-13.5, and 16.8-22.8 days, respectively. It was estimated that 13.00 and 4.44 g a.i./lOa were the rates of buprofezin which could show mortalities of 2nd instar BPH larvae above 95% and 50% until 15 OAT, respectively. The residual lethal effect of 7.00 g a.i./10a on the 1st instar BPH larvae was 100 % even on 17 OAT. $RLT_{50}$ was 32.5 days which was 15 days longer than $RLT_{50}$ for the 2nd instar larvae. Buprofezin with 7.0 g a.i./lOa showed 100% and 70% mortality for 1st-4th and 5th instar BPH larvae, respectively. Longevity of a female BPH which emerged from the 5th instar larvae treated by buprofezin was greatly reduced, and its fecundity was nearly zero.

• Journal of Life Science
• /
• v.22 no.12
• /
• pp.1614-1620
• /
• 2012

Transgenic rice plants with increased resistance to rice brown planthopper (Nilaparvata lugens St${\aa}$l) were generated by particle bombardment-mediated transformation of plants with a gene encoding snowdrop lectin (Galanthus nivalis agglutinin; GNA) under control of the rice Rubisco small subunit (rbcS) promoter.. A large number of transgenic rice plants containing the GNA gene were generated. The integration, expression, and inheritance of this gene in the $R_1$ and $R_2$ generations were demonstrated by Southern and western blot analyses. The plants contained one to five copies of the transgene. The GNA protein comprised approximately 0.01-2.0% of total soluble protein in the $R_1$ and $R_2$ transgenic plants. Insect bioassays and feeding studies showed that the GNA protein expressed in the $R_2$ transgenic rice plants reduced the survival of brown planthoppers. The introduction of GNA into rice plants therefore can help to control insect pests.

• Korean Journal of Environmental Agriculture
• /
• v.16 no.4
• /
• pp.347-355
• /
• 1997

For the selection of plants contained pesticidal active conpounds, 31 families 59 species of native plants were collected and biological activites of their crude extracts against brown planthopper (Nilaparvata lugens), Xanthomonas oryzae pv. oryzae and allelopathy were examined. Among the screened plants, the crude extracts from the leaves of Ricinus communis and Sophora angustifolia showed 100% and 82% of mortality on brown planthopper at the concentration of 1% (w/v) respectively. Mixed crude extracts of Sophora angustifolia root and Melia azedarach seed exhibited 128${\sim}$155% of synergistic effects on the mortality of brown planthopper. In case of fungicidal activity, the crude extracts from the leaves of 8 plants including Chrysanthemum indicum were inhibitory of the growth of Xanthomonas oryzae pv. oryzae at 1%(w/v) soluction. Seed germination of radish (Raphanus sativas) and barnyardgrass (Echinochloa crus-galli) was inhibited by 0.5%(w/v) leaf extracts of Pinus densiflora and Quercus acutissima. MeOH extracts of Pinus denislora leaves gave 100% inhibition in seed germintion of radish at 2%(w/v) soluction and showed a complete inhibition in seedling growth of barnyardgrass as well as radish at 5% solution.

• Korean Journal of Breeding Science
• /
• v.43 no.1
• /
• pp.56-61
• /
• 2011

Brown planthopper(BPH) is one of the most destructive insect pests of rice. The use of genetically resistant cultivars has proven to be a more economical, efficient and environment friendly means to combat this pest. This study was carried out to investigate the relationship between BPH resistant gene, Bph18 and yield components of rice using DH(doubled haploid) lines derived from 'Saenuri'/SR30071-3-7-23-6-1-1-1. SR30071-3-7-23-6-1-1-1 line has Bph18 gene derived from wild species, Oryza australiensis. BPH resistant gene, Bph18 shortened heading days, enlarged culm length and panicle length and reduced ratio of ripened grains of rice. The results indicate that backcrossing breeding is necessary to develop elite cultivars carrying Bph18 gene.

• Journal of Life Science
• /
• v.29 no.2
• /
• pp.202-208
• /
• 2019

Brown planthopper (BPH), Nilaparvata lugens Stål (Hemiptera: Delphacidae), is one of the most important migratory pests damaging rice in Korea. It invades annually from tropical and subtropical areas via continental air streams. It is necessary to determine the resistance levels of rice varieties in order to control efficiency. The honeydew excretion, development, and reproduction of the migratory BPH were studied by region in a laboratory at $25{\pm}2^{\circ}C$ and $65{\pm}5%\;RH$ and a 16L: 8D photoperiodism conducted on three BPH resistant genes: Bph1, Bph2, and Bph18. The information obtained was reported using the jackknife method, and we created life table statistics accordingly. The feeding amount of Bph1 resistant gene was lower than that of resistant genes. The developmental periods of immature stages ranged from $13.7{\pm}0.10d$ on Bph2 (Namhae, 2015) to $18.5{\pm}1.06d$ on Bph2 (Sacheon, 2016). Reproductive period and female longevity were longest on the non-resistant genes, Bph2 and Bph18 (except 1980s), and the highest fecundity of N. lugens was observed on the two BPH resistant genes. Highest net reproductive rates ($R_0$) were calculated on Bph2 by region. Intrinsic rates of population increase ($r_m$) showed a difference in resistant genes by region. These population parameters showed that migratory regions and biological characteristics of N. lugens vary annually.