• Korean journal of applied entomology
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• v.53 no.4
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• pp.497-501
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• 2014

The small brown planthopper, Laodelphax striatellus (Fall$\acute{e}$n) (SBPH) is one of the important rice pests in Korea, which transmits rice stripe virus (RSV) to rice. This pest is an indigenous species in Korea and has also known to migrate from China to the western coastal areas of Korea. This study was conducted to investigate the wing morphs of SBPH and its parasitism rate of Haplogonatopus atratus Esaki et Hashimoto in Korea. In 2014, SBPH were collected in April and July from 16 sites throughout South Korea and their wing morphs and parasitism rates were measured under the microscope. Percentage of brachypterous male in July was significantly declined compared to that in April, while that of brachypterous female did not change. A positive relationship was found between latitude and percentage of brachypterous adults in April. Parasitism rate of both nymphs and adults were higher in April than July. In addition, nymphal parasitism rate was generally higher in western coastal areas.

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

• Research in Plant Disease
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• v.24 no.3
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• pp.202-212
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• 2018

Major viruses infecting rice are transmitted by planthoppers such as small brown planthopper (SBPH), brown planthopper (BPH) and white-backed planthopper (WBPH). In this study, we investigated planthoppers captured during 2015 to 2017 by a smart sky net trap (SSNT) system installed in 40 areas in Korea, which is an automatic, rapid and real-time insect surveillance system. The average rates of captured migration plnathoppers was 27.5%, 17.2%, 15.3% and 10.9% in Chungcheongnamdo, Jeollanamdo, Jeollabukdo and Gyeonggido, orderly. The highly migrated month was July for SBPH, July to August for WBPH and August for BPH. To investigate the viruliferous rates of planthoppers of rice during 2015 to 2017, we performed RT-PCR using specific primers for each rice virus. RBSDV was detected from 0.4% in SBPH, while no viruses were detected in BPH and SBPH. Rice planthoppers exist all around in Asia. They can move long distance by wind from southern countries to Korea. Monitoring the migration of rice planthoppers and their viruliferous rates is important to prevent the outbreaks of rice virus diseases.

• Korean journal of applied entomology
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• v.23 no.4 s.61
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• pp.233-236
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• 1984

Studies were conducted to investigate the effect of Carbofuran 3G on the density variation of rice pests and their natural enemies in case the insecticide was treated two times as compared with usual trials in paddy field. Even the two times application of Carbofuran 3G in the nursery boxes of machine transplanting and paddy water trials obtain same results to pests, small brown planthopper (Laodelphax striatllus), green rice leafhopper (Nephotettix cincticeps), brown planthorper (Nilaparvata lugens), white back planthopper (Sogotella furcifera), rice stem bore (Chilo suppressalis), rice stem maggot (Chlorops oryzae), rice thrips (cloethrips oryzae) as compared with usual trials. The density of natural enemies, spiders and egg parasite, Anagrus sp. of planthoppers in the two times application part of Carbofuran 3G increased 2.4 fold as compared with usual trials.

• Korean journal of applied entomology
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• v.33 no.1
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• pp.19-25
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• 1994

Electrophysiological recordings of antennal responses to common plant volatile chemicals in the rice brown planthopper, Niloparuota lugens (Homoptera: Delphasidae}, were examined. Volatile plant chemicals were generally credited with a major role In host plant location for food or egg laying by many insects feeding on plants as adults and/or as larvae. An mitial examination of extracellular responses has been conducted. Acton potentials recorded from the plaque organs were initially positive-going, biphaslc spikes and the background firing rate of the cells recorded ranged from 1 ~22 impulses/sec. A wide range of responses to changes in concentration of the test chemical was observed. The commonest response was a relatively small increase in exitation with increasing concentration beween 1 J.lg and 100).\g on the filter paper in syringe. Adtivity either peaked at 100 $\mug$ and remained virtually saturated at 1000 f19 or tended to decrease at the highest concentration.

• Korean journal of applied entomology
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• v.52 no.4
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• pp.427-430
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• 2013

Recently, climate change scenarios were substituted by the Special Report on Emission Scenarios (SRES) for Representative Concentration Pathway (RCP). Using the RCP scenario, the World Meteorological Organization (WMO) produced new climate change scenarios. Further, the National Institute of Meteorological Research (NIMR) of Korea produced new climate change scenarios for the Korean Peninsula. In this study, emergence time of small brown planthopper (SBPH), Laodelphax striatellus and the number of generations a year were estimated during climatic normal year (1981-2010) with previous studies and they were predicted during 2050s (2045-2054) and 2090s (2085-2094) by means of RCP8.5 climate change scenario. In comparison with $176.0{\pm}0.97$ Julian data in the climatic normal year, the emergence time of overwintering SBPH was predicted to be $13.2{\pm}0.18$ days ($162.8{\pm}0.91$ Julian date) earlier in 2050s and $32.1{\pm}0.61$ days ($143.9{\pm}1.08$ Julian date) earlier in 2090s. The SBPH was expected to produce an additional $2.0{\pm}0.02$ generations in 2050s and $5.2{\pm}0.06$ generations in 2090s.

• Korean journal of applied entomology
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• v.15 no.4 s.29
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• pp.179-184
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• 1976

Laboratory experiments were conducted to clarity the early-spline host·selectivity by the small brown planthopper(SBPH), Laodelphax striatellus Fallen, and green rice Leafhopper(GLH), Nephotettix cincticeps Uhle., on the bailey (the variety Suweon #18) and water foxtail (Alopeculus aequadis Sosbol). The host selectivity was evaluated on the bases of feeding and ovipositional perferences of the insects on the plants and their biological effects on the plants. The nymphs of SBPH much more preferred barley for feeding than water forxtail, while the nymphs of GLH relatively prefered water foxtail. There was no significant difference in ovipositional preference by SBPH among the test plants, and ovipositional preference by GLH Ivas significantly lower on barley and water foxtail than on rice. Nymphal growth an4 adult emergence of SBPH were significantly faster and higher on barley than on water foxtail. No adult emergence of GLH was observed on barley, and adult emergence was still quite lower even on water foxtail. The adult of SBPH fed on barley showed longer longevity aad higher fecundity than that of SBPH from water foxtail and rice. The adult GLH fed ell water foxtail shorted relatively shorter longevity and to)ver fecundity than that of GLH on rice. In conculsion, barley seems to be more adequate for spring host of SBPH than water foxtail, but barley may not be quite adequate for spring host of GLH. At presont moment, GLH seems rather to primarily select the water foxtail than barley as a spring host, even if the water foxtail is not so adequate for development of GLH.

• Research in Plant Disease
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• v.19 no.2
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• pp.84-89
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• 2013

The incidence factors of Rice stripe virus (RSV) were analyzed by studying the population density and the viruliferous insect rate (VIR) of small brown planthopper (SBPH), the incidence of stripe disease, alternate host, and susceptible cultivar in Chungnam Province. The population of overwintering SBPH had been decreasing, but the VIR of overwintering SBPH had not been differing for three years, 2008 to 2010. No RSV was detected in the natural host plants, such as short awn, annual bluegrass, and barley. In 2009, relatively large population of SBPH with the VIR of 5.4% migrated from China. However, there was no evidence relating of migration large amount of SBPH from China in 2008 and 2010. Also the infection rate of RSV in rice was less than 1% in these periods. The cultivation area of the susceptible varieties had steadily decreased from 41% to 19% from 2007 to 2009. Therefore, the reduction factors of rice stripe disease in Chungnam Province with higher influx of inoculum could be with an appropriate forecasting and chemical control, cultivation of resistant varieties, changes in the cropping system, and the low winter-spring temperature.

• Korean journal of applied entomology
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• v.54 no.4
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• pp.419-423
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• 2015

Small brown planthopper (SBPH), Laodelphax striatellus, gives a lot of damage to the rice by insect vector of rice stripe virus (RSV). This study compared the RSV acquisition and infection rates according to wing form, sex, and life stage of SBPH. The RSV acquisition rate in macropterous and brachypterous was 60.7% and 63.1%, respectively. The RSV acquisition rate by sex was 61.9% in female and 52.2% in male. However, there was no difference in significance. The RSV acquisition rate of nymphs and adults was 51.2% and 58.7%, respectively. The RSV infection rate by wing form was 53.3.% in macropterous and 48.2% in brachypterous. According to life stage, nymphs was 38.2% and adults was 42.6%. There was no difference in significance. On the other hand, female and male of RSV infection rate was 50.5% and 22.3%, respectively. There was a significant difference. Additionally, developmental periods of SBPH by RSV infection, the longest when inoculated with RSV-infected SBPH in healthy rice, while the shortest when inoculated healthy SBPH in healthy rice.

• Korean journal of applied entomology
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• v.16 no.4 s.33
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• pp.217-220
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• 1977

During 1976 the effects of carbofuran placement in the root zone of the rice plants, the varieties Palkweng and Yushin, were evaluated for control of common rice pests in the paddy field at the Honam Crops Experiment Station. The methods of insecticide placement included the use of capsule formulation and liquid injection by the root-zone liquid insecticide injector designed at the International Rice Research Institute. The single ro~t-zone application of carbofuran at 2 days after transplanting was compared with two and fcur broadcast applications of carbofuran and diazinon. Capsules were the most. effective in controlling the striped rice borer (Chilo suppressalis), small brown plant-hopper (Laodelphax striatellus), green rice leafhopper (Nephotettix cincticeps) and stripe virus disease which is transmitted by the small brown planthopper. However, one injector application of carbofuran was equal or better the broadcast applications. Their control effectiveness were more significant on Palkweng susceptible to common rice pests than on Yushin resistant to the stripe virus disease.