Rice stripe virus (RSV), the type member of the genus Tenuivirus, causes rice stripe disease and the viral transmission is mediated through the sucking by small brown planthopper, Laodelphax striatellus. Considerations have been mainly focused on the protection of rice from RSV and/or the planthopper, rather than the interaction between RSV and the insect. To clarify the interaction, in this work, mRNA was extracted from RSV-viruliferous planthopper with non-viruliferous control, and expressed sequence tag (EST) databases were generated based on 454 GS-FLX pyrosequencing technology for comparative analysis. RSV-viruliferous planthopper had ca. 2500 isotigs, which included genes on biological process (19%), cellular component (13%), molecular function (22%) and no hits (46%) from gene ontology (GO) analysis; this structure was similar to the control. However, in the viruliferous planthopper, 109 isotigs were up-regulated and 660 isotigs were down-regulated, compared to the non-viruliferous control. These RSV-dependently regulated genes may have important function in the behavior of planthopper or the transmission of RSV.
Spodoptera exigua is a significant polyphagous pest in the greenhouse and open field. Our aim of this study was to evaluate light emitting diodes (LEDs) as the potential attractants against Spodoptera exigua on various wavelengths, light intensity, and light duration. The preference response to S. exigua was investigated by the laboratory and field-scale. The wavelengths of LEDs were composed as follows: blue (470 nm), green (520 nm), yellow (590 nm), red (625 nm) and white (450-620 nm). When the optimal light condition was investigated in the laboratory scale, the all light treatments attracted the highest number of S. exigua at 40 lux intensity and 60 min duration. Based on the wavelengths under optimal light condition, the white LED exhibited the highest attraction rate (91.1%), followed by green (88.9%), blue (81.1%), yellow (63.3%) and red (56.7%), respectively. In comparison with the selected white LED and yellow sticky traps in the field-scale, the white LED (81.3%) was about 16.26 times more attractive than yellow sticky trap (5.0%). These results clearly show that the white LED had the greatest attraction against S. exigua.
The object of this study is to observe the attraction of specific wavelengths against Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae). The attractive effects was examined by the high power light-emitting diodes (HPLEDs) in the dark room at 27±0.5°C and 60±0.5% relative humidity. Evaluated specific wavelengths were blue (470±10 nm), green (520±5 nm), yellow (590±5 nm) and red (625±10 nm) HPLEDs. When a light exposure time was fixed at 60 min and tested with various illuminance intensity at 20, 40, 60, 80, and 100 lux, the attraction rate of the green HPLED at 80 lux was the most effective (94.4%) to B. tabaci, followed by yellow HPLED of 20 lux (78.9%), blue HPLED of 60 lux (71.1%), and red HPLED of 20 lux (60.0%), respectively. According to the change of light exposure time (10, 20, 30, 40, 50, and 60 min), green HPLED showed the potential attractive effects under the 40 min and 50 min. These results suggest that it is possible to develop a green HPLED trap for attracting, monitoring, and lighting system against B. tabaci.
To evaluate potential attractive activity of high power light emitting diodes (HPLEDs) against Plutella xylostella (Lepidoptera: Plutellidae), the specific wavelengths, illuminance intensities (20, 40, 60, 80, 100 lux), and light exposure times were investigated at 5 minute intervals. The evaluated specific wavelengths were blue (450±10 nm), green (520±5 nm), yellow (590±5 nm), red (660±10 nm), and white (450-630 nm). Based on the highest attraction rate, the HPLEDs treated to 60 lux intensity against P. xylostella were significantly more attractive than other illuminance intensities when light exposure time was 10 min. Attraction rate under optimal conditions showed that the green HPLED had the highest attraction rate (98.3%), followed by red HPLED (89.3%), blue HPLED (86.7%), yellow HPLED (76.7%), and white HPLED (70.0%), respectively. These results indicated that phototatic effect of the green HPLED against P. xylostella showed the greatest attraction at 60 lux intensity and 10 min light exposure time. Further research needs to be performed to evaluate the phototatic behavioral responses to single and multiple HPLED sources in the field.
호박과실파리(Bactrocera depressa)는 우리나라, 일본, 대만에 발생하는 해충으로 우리나라의 경우 주로 산간지대(해발 300~399m)에서 피해가 보고되고 있다. 주요 피해로는 교미한 성충 암컷이 박과류의 어린 과육에 산란을 하고 부화한 유충이 박과류의 내부를 가해한다. 아직까지 국·내외 유인물질 및 방제방법에 관한 연구가 이루어지지 않고 있어 피해가 지속적으로 증가하고 있는 실정이다. 본 연구는 2011년 강원도 홍천 단호박(보짱)을 중심으로 호박과실파리의 산란특성 파악과 봉지 씌우기를 이용한 물리적 방제방법을 모색하였다. 무처리구에서 호박과실파리의 피해는 꽃이 진 어린과육에서 평균 2.3개의 산란 흔적이 발견되었고, 과육의 경도가 증가할수록 산란 흔적은 줄어들었다. 4종의 봉지 씌우기를 이용한 물리적 방제에서 황색이중봉지 0%, 백색봉지에서 3%, 피톤치드이중봉지 0%, 무처리 10%의 피해양상을 보였다. 봉지씌우기에 따른 호박과피 색도의 Hue angle값은 피톤치드이중봉지가 239.3°을 보였고 백색봉지가 243.3°를 나타내었다. 당도는 백색봉지가 16.6Brix였고 무처리는 12.3Brix였다. 무게는 황색이중봉지가 365g으로 가장 낮았고 무처리가 400g으로 가장 좋았다.
The rice weevil, Sitophilus oryzae, is the most serious storage pests worldwide of grocery shops, flour mills, and warehouses. The phototactic response of the rice weevil, S. oryzae, to light emitting diodes (LEDs) at five different wavelengths and various light intensities was tested within an LED-equipped Y-maze chamber, and compared with its response to a luring lamp, which is used in commercial traps. Various wavelengths in this study were UV (365 nm), blue (450 nm), green (520 nm), red (660 nm), and infrared (IR) (730 nm). Based on attraction rate (%), blue (84.3%) was the most attractive to S. oryzae, followed by green (74.3%), red (64.3%), UV (63.3%), and IR (48.7%). Moreover, blue and green wavelengths were 1.5 and 1.3 times more attractive than luring lamp (56.7%), whereas the UV wavelength was slightly less attractive to the weevils than luring lamp. These results suggested that blue and green wavelengths could be more useful than those currently used for monitoring and mass trapping of S. oryzae.
5-Hydroxy-1,4-naphthoquinone and its derivatives were evaluated for insecticidal effect against Sitophilus oryzae and S. zaemais adults. This study was examined using fumigant method. Mortality was determined after 72 h of treatment. 5-Hydroxy-1,4-naphthoquinone showed strong (+++) activity at 5 mg and the 1,4-naphthoquinone showed strong (+++) and moderate (++) activity at 5 mg, against S. oryzae and S. zaemais, respectively. However, 5-hydroxy-2-methyl-1,4-naphthoquinone, 2-methyl-1,4-naphthoquinone, 2-hydroxy-1,4-naphthoquinone, and 2-methoxy-1,4-naphthoquinone had non-activity (-) at 5 mg. Based on the LD50 values, the compound most highly effect to S. oryzae was 1,4-naphthoquinone (0.012 mg/cm2), followed by 5-hydroxy-1,4-naphthoquinone (0.013 mg/cm2). However, against S. zeamais, 5-hydroxy-1,4-naphthoquinone (0.044 mg/cm2) was the most toxic compound, followed by 1,4-naphthoquinone (0.155 mg/cm2). These results suggest that the introduction of various functional group (hydroxy, methyl and methoxy) into the 1,4-naphthoquinone skeleton contributes to insecticidal activity. Accordingly, 5-hydroxy-1,4-naphthoquinone and 1,4-naphthoquinone could be used highly effective rice weevil control agents.
This study was performed to evaluate the contact toxicity and residual toxicity of the 26 commercially registered insecticides against cigarette beetle, Lasioderma serricorne and maize weevil, Sitophilus zeamais adult. Among 26 insecticides, seven insecticides (chlorpyrifos, chlorpyrifos-methyl, fenitrothion, fenthion, phenthoate, cypermethrin, α-cyhalothrin) against L. serricorne adult and five insecticides (chlorpyrifos, chlorpyrifos-methyl, fenitrothion, fenthion, phenthoate) against S. zeamais adult showed perfect mortality. LC50 (ppm) values of those selected insecticides were appeared lowest value on α-cyhalothrin (1.46 ppm) against L. serricorne adult and chlorpyrifos-methyl (0.64 ppm) against S. zeamais adult, respectively. However, chlorpyrifos-methyl still remain high toxicity until 90th days after treatment against both L. serricorne and S. zeamais adults. From above results, it will be useful information to select insecticides effective against L. serricorne and S. zeamais adults.
배 과원 문제해충의 하나인 꼬마배나무이(Cacopsylla pyricola)의 월동성충이 낳은 알의 온도별 부화율 변화를 조사한 결과, 23℃와 18℃에서 각각 9, 11일후 80% 이상부화하였고, 13℃에서는 18일 후에 80% 이상 부화하였다. 나주에 위치한 배시험장 포장에서 일별 부화율을 조사한 결과, 부화율 50%를 초과일은 ’11년 4월 13일이었다. 월동성충 방제적기 모델과 유사하게 2월 1일부터 일일 최고기온 6℃ 이상의 온도를 누적한 결과, 424.3일도였으며, ‘08년과 ’09년에 50% 이상 알 부화일은 각각 4월 11일, 4월 6일인데 같은 방법으로 누적적산온도를 계산한 값은 각각 429.7일도, 417.6일도였다. 한편 ‘11년 부화 비율이 50%와 80%를 초과한 시점에 10종의 친환경 자재를 처리하고 처리 10일후 잎당 발생밀도를 조사한 결과, 고삼(뿌리) 추출물 제품이 각각 0, 0.02마리로 가장 낮은 밀도를 보였다.
오이 봄재배시기인 2월부터 6월까지 발생하는 주요해충에 대하여 천적을 이용한 생물학적 방제효과를 검토하기 위해 본 연구를 수행하였다.
본 연구의 수행을 위하여 해충발생량 조사는 충청남도 공주시와 천안시의 오이재배단지에서 수행하였으며 생물학적 방제효과를 검토하기 위하여는 충남농업기술원 내의 무가온 하우스에서 수행하였다. 천적보호식물 및 유인식물을 투입하고 병해충에 기계적 및 화학적 방어기작 유도를 위한 액상규산 2,000배를 15일 간격으로 관주하면서 천적을 투입한 시험구와 천적만을 방사한 시험구에서 천적에 의한 해충방제효과를 비교하였다.
봄오이 재배기간에 발생하는 주요해충은 목화진딧물, 담배가루이, 총채벌레, 굴파리 였으며, 목화바둑명나방은 7월 이후 발생하는 양상을 보였고, 싸리수염진딧물, 긴털가루응애, 차먼지응애는 일부지역에서 피해를 주었다. 천적유인식물에서 조사한 천적의 발생양상을 관찰한 결과, 기장태두리진딧물과 보리두갈래진딧물이 혼서하는 보리에서 콜레마니진디벌, 진딧물 기생성 좀벌류, 미끌애꽃노린재, 굴파리좀벌, 잎굴파리고치벌의 쉽게 관찰되었으며 자운영과 별꽃에서도 천적들이 관찰되었다. 액상규산의 처리가 해충의 발생에 미치는 영향평가를 위하여 목화진딧물, 총채벌레, 담배가루이의 밀도를 조사한 결과 모든 해충에 대하여 액상규산이 처리된 곳 보다 처리되지 않은 곳에서 유의성 있게 더 많이 유인되었다. 천적보호 및 유인식물(BIPP, Benificial Insect Protective Plant), 천적(NE, Natural Enemy), 액상 규산(Si, Silicate)을 동시 활용한 해충방제효과를 조사한 결과 목화진딧물의 경우 엽당 1마리 이하의 밀도를 유지하였고, 총채벌레의 경우 꽃당 1마리 이하의 밀도를 유지할 수 있었으며, 담배가루이의 경우 신초당 성충 1마리, 굴파리의 경우 주당 20개 굴수 이하로 유지 할 수 있었다. 천적만을 활용한 2010년의 경우는 이보다 높은 밀도를 유지하였다.
Although baculoviruses have a long history of safe use as specific, environmentally benign insect control agents, their use has been limited by several factors, especially their slow speed of action. In this study, we intended to improve the insecticidal activities of Autographa californica nucleopolyhedrovirus (AcMNPV) by expressing Kunitz-type toxin isolated from venoms of Bombus ignitus or Araneus ventricosus. For this, recombinant AcMNPVs, AcBi-KTT, AcAv-Tox1 and AcAv-Tox2 expressing Bi-KTT, Av-Tox1 and Av-Tox2, respectively, under the control of p10 gene promoter were constructed. While polyhedra produced by these recombinant viruses were identical to those of the wild-type AcMNPV in shape, their sizes were relatively smaller than those of the AcMNPV. Among recombinant viruses, AcBi-KTT and AcAv-Tox2 showed significant reduction in median lethal time (LT50) against Spodoptera exigua larvae. Especiaaly, these two viruses showed about 6.2~10-folds higher polyhedra production rate compared to that of the AcMNPV. These results suggested that Kunitz-type toxins from insect venom could be successfully applied to improve insecticidal activity of baculoviruses.
학교숲운동을 비롯하여 녹색학교(녹색성장시범 ․ 연구학교), 학교공원화 사업, 담장 허물기 사업 등 다양한 단체, 기관, 지자체에서 학교숲을 조성하는 사업이 진행되어 전국적으로 약 3,000개 이상의 학교에서 학교숲을 조성하였다. 본 연구는 전국 6개 시·도에 소재하는 111개 학교숲에 식재되어 있는 수종 및 발생 해충을 조사하고, 지역별 수종의 특성 및 발생 해충에 대한 관리방안을 제시하고자 수행되었다. 조사결과, 전국 6개 시·도의 111개의 학교숲에 가장 많이 식재된 수종은 철쭉류, 단풍나무류, 느티나무, 소나무, 은행나무, 향나무, 회양목, 주목, 목련, 벚나무 순이었으며, 지역적으로 수종 간 차이가 다소 나타났다. 학교숲에 가장 많이 발생하는 해충은 응애류, 진달래방패벌레, 깍지벌레류, 진딧물류, 미국흰불나방, 회양목명나방의 순이었다. 학교숲은 학생과 교직원이 이용하고 교육에 활용되는 장소이므로 최소한의 화학적 방제에 의한 관리와 교육의 측면에서 생물학적 방제에 의한 관리가 필요한 곳으로 판단되기에 주요 관리대상 수목의 종류와 해충의 종류를 선발하였으며 해충 연간 관리력에 따른 관리방안을 제안하고자 하였다.