친환경 딸기 재배 농가에서 칠레이리응애를 이용한 점박이응애 생물적 방제

김도익,김선곤,신길호,서종분,최경주,임경호,김상수 한국유기농업학회 2006 韓國有機農業學會誌 Vol.14 No.3

The potential of the predatory mite Phytoseiulus persimilis (Acarina : Phytoseiidae) to control two spotted spider mite Tetranychus urticae (Acarina : Tetranychidae) was investigated on sustainable strawberry fields in Jeonnam area. The density of T. urticae increased from 4th and 7th weeks after single and two timings release P. persimilis, respectively. On the three timings of release plot, number(density) of T. urticae on a leaf maintained fewer than 10 during the 15 weeks after release. In the 1,000 release of P. persimilis per 100㎡ plot, P. persimilis could not suppress T. urticae. In the 2,000 release plot, P. persimilis could suppress T. urticae with low density which was the similar in the 3,000 release plot. Twospotted spider mite, T. urticae, occurred from late March and increased density in Hampyeong area. In the P. persimilis released field, T. urticae inhibited continuously after release. In Boseong area, density of P. persimilis increased 50 per 10 leaves through increasing of T. urticae. Percent of occurrence of T. urticae showed high 10.5~75.5% in none-release predatory mite but not high in release treatment. T. urticae on sustainable strawberry field could be inhibited by P. persimilis.

Ethyl formate and phosphine fumigations on the two‑spotted spider mite, Tetranychus urticae and their biochemical responses

김경남,이용호,김가영,이병호,양정오,이성은 한국응용생명화학회 2019 Applied Biological Chemistry (Appl Biol Chem) Vol.62 No.5

Two spotted spider mite, Tetranychus urticae, is a polyphagous pest to a variety of plants and they are hard to be controlled due to occurrence of resistance to acaricides. In this study, biochemical evaluation after ethyl formate (EF) and phosphine ( PH3) fumigation towards T. urticae might help officials to control them in quarantine purposes. PH3 fumigation controlled eggs ( LC50; 0.158 mg/L), nymphs ( LC50; 0.030 mg/L), and adults ( LC50; 0.059 mg/L) of T. urticae, and EF effectively affected nymphs ( LC50; 2.826 mg/L) rather than eggs ( LC50; 6.797 mg/L) and adults ( LC50; 5.836 mg/L). In a longer exposure time of 20 h, PH3 fumigation was 94.2-fold more effective tool for control of T. urticae than EF fumigant. EF and PH3 inhibited cytochrome c oxidase (COX) activity differently in both nymphs and adults of T. urticae. It confirmed COX is one of target sites of these fumigants in T. urticae and COX is involved in the respiratory chain as complex IV. Molecular approaches showed that EF fumigation completely down-regulated the expression of cox11 gene at the concentration of LC10 value, while PH3 up-regulated several genes greater than twofold in T. urticae nymphs treated with the concentration of LC50 value. These increased genes by PH3 fumigation are ndufv1, atpB, para, and ace, responsible for the expression of NADH dehydrogenase [ubiquinone] flavoprotein 1, ATP synthase, and acetylcholinesterase in insects, respectively. Lipidomic analyses exhibited a significant difference between two fumigants-exposed groups and the control, especially an ion with 815.46 m/z was analyzed less than twofold in the fumigants-treated group. It was identified as PI(15:1/18:3) and it may be used as a biomarker to EF and PH3 toxicity. These findings may contribute to set an effective control strategy on T. urticae by methyl bromide alternatives such as EF and PH3 because they have shared target sites on the respiratory chain in the pest.

Control efficiency of the predatory mites, Neoseiulus californicus and Phytoseiulus persimilis, for Tetranychu urticae on a spatially-structured strawberry leaf disc arena

Jeong Joon Ahn,Joon-Ho Lee 한국응용곤충학회 2010 한국응용곤충학회 학술대회논문집 Vol.2010 No.05

Strawberry, Fragaria ananassa Duchesne, is one of the important horticultural crops cultivated in greenhouses. Tetranychus urticae is one of major strawberry pests, and Neoseiulus californicus and Phytoseiulus persimilis have been used as biological control agents for control of T. urticae. The interactions between T. urticae and N. californicus and between T. urticae and P. persimilis were investigated to compare their control efficiency for T. urticae on a spatially-structured strawberry leaf disc area at different temperatures and on different treatments. The experimental arena was an array of leaf discs (3 cm diameter) placed upside down on a water-saturated cotton pad in an aluminum pan (17.4 x 21.5 cm). Twenty leaf discs (4 x 5) were placed adjacent each other for allowing dispersal of T. urticae and its predatory mites. The temperature conditions were 20, 25, and 30°C and there were six different treatments. The overall population densities of T. urticae were influenced by temperature (20, 25, and 30°C) in N. californicus treatment. In the same temperature condition, P.persimilis was more effective than N. californicus to control T. uritcae. Two predator systems were better than one predator systems to suppress the population density of T. urticae at 25°C. Some results of this study could be used to understand the spatial association of T. urticae and its predatory mites in greenhouse crops and fields.

Evaluation of the Effective Inoculation Position for Neoseiulus californicus McGregor (Acari: phytoseiidae) for Control of Tetranychus urticae Koch (Acari: tetranychidae) on Apple Branch

TaeGyun Kim,YongJun Kwon,JeongJoon Ahn,Joon-Ho Lee 한국응용곤충학회 2009 한국응용곤충학회 학술대회논문집 Vol.2009 No.05

The objective of this study was to evaluate the effective inoculation position of Neoseiulus californicus for control of Tetranychus urticae on apple branch. This study was conducted under green house conditions. N. californicus was inoculated at different position (Top, Middle and Bottom) of apple branch with a 20:1 ratio (T. urticae:N. californicus). Overall, N. californicus significantly reduced T. urticae numbers in the treatment branches than in the control branch. At 10th day, the T. urticae population was most significantly reduced in the treatment ‘Top’ in which N. californicus were inoculated on the leaf positioned in the top of a branch than in other treatments. At 20th day, most of T. urticae were exterminated in all treatment branches. The daily movement of N. californicus and T. urticae,and their coexistence on apple branch was monitored. Adult N. californicus disappeared from the branch as soon as T. urticae were exterminated in the treatment branches. The result indicates that N. californicus disperse downwards more than upwards in the tree, and the most effective inoculation position for N. californicus for control of T. urticae is the leaves positioned in the top of a branch.

Application of Natural Enemy and Selective Pesticides for the Control of Two-Spotted Spider Mite on Strawberry

Ahn Ki-Su,Changmann Yoon,Young Ho Kim,Gil-Hah Kim 한국응용곤충학회 2016 한국응용곤충학회 학술대회논문집 Vol.2016 No.04

The two-spotted spider mite Tetranychus urticae is being steadily problematic on strawberry. To effective control of this pest, one combination application using predatory mite Phytoseiulus persimilis plus a pesticide Acequinocyl suggests. Prepared six beds (1.5 × 3 m; 20 strawberry plants) on glass house, 100 T. urticae was inoculated on per 20 plants. Four plots prepared - Acequinocyl treatment, P. persimilis application, Acequinocyl+P. persimilis double application, and the control. The change of T. urticae density was investigated in the seven-day intervals. In an Acequinocyl treated plot, T. urticae density was decreased after Acequinocyl sprayed, but began to increase steadily one month later. In a P. persimilis applied plot, T. urticae density began to decrease at 20 days after P. persimilis inoculation. In an Acequinocyl + P. persimilis double applied plot, T. urticae density was dramatically decreased after application and then no found the T. urticae. To practical use in farmhouse, it will be possible to control by inoculation of P. persimilis only when low density of T. urticae; however, double application with spray pesticide Acequinocyl plus apply the natural enemy P. persimilis will be good when high density of T. urticae.

Comparison of Single and Combination use of Neoseiulus californicus and Neoseiulus womersleyi for Control of Tetranychus urticae

TaeGyun Kim,Jeongjoon Ahn,YongJun Kwon,Joon-Ho Lee 한국응용곤충학회 2009 한국응용곤충학회 학술대회논문집 Vol.2009 No.05

This study was conducted to compare the effectiveness of single and combination use of N. californicus and N. womersleyi for control of Tetranychus urticae. The experiment was conducted with 5 replications in kidney bean leaf disc (2.5cm diameter) at 25℃, 60-70% RH, a photoperiod of 16:8 (L:D) h. The inoculation ratio was 5:1 for T. urticae:pytoseiidae mite and treatments are: a, N. californicus:T. urticae (4 adult female:20 adult female) b, N. womersleyi:T. urticae (4:20) c, (N. californicus+N. womersleyi):T. urticae ((2+2):20) d, Only T. ulticae (20). T. urticae population became significantly lower in the treatment plots than in the control plot but the higher egg number of T. urticae was observed in the treatment "b" plot than in "a" and "c" plots. In the "c" plot, lower number of N. womersleyi was observed than N. californicus. The result indicates that single use of N. californicus and combination use of N. californicus and N. womersleyi were more effective than single use of N. womersleyi but, there was no significantly difference between single use of N. californicus and combination use of N. californicus and N. womersleyi for control of T. urticae. Also, N. californicus appears to interfere or outcompete N. womersleyi.

Seasonal dynamics of economic injury levels for <i>Tetranychus urticae</i> Koch (Acari, Tetranychidae) on <i>Cucumis sativus</i> L.

Park, Y.-L.,Lee, J.-H. Blackwell Publishing Ltd 2007 Journal of applied entomology Vol.131 No.8

<P>Abstract: </P><P>Economic injury level (EIL) for <I>Tetranychus urticae</I> Koch on glasshouse cucumbers was established in two ways: EILs based on the number of <I>T. urticae</I> introduced to cucumber early in the growing season and EILs based on mite density and feeding durations (i.e. cumulative mite-days) in each of four growing seasons. The relationship between yield loss and <I>T. urticae</I> infestation level varied among four growing seasons. One mite introduced to cucumber early in the growing season could reduce the cucumber yield by 5.03, 3.20, 1.12 and 2.86 g per plant in spring, summer, autumn and winter, respectively. One mite-day (i.e. one mite feeding in a day) reduced cucumber yield by 0.0123, 0.0074, 0.0035 and 0.0073 g per plant in spring, summer, autumn and winter, respectively. When the seasonal dynamics of market values of cucumber was considered, EILs were the lowest in spring and the highest in autumn. When four seasonal data were combined, EILs can be calculated as EIL = <I>C</I>/(0.00276 × <I>K</I>) for the number of <I>T. urticae</I> introduced early in the growing season and EIL = <I>C</I>/(6.8342 × 10<SUP>−6</SUP> × <I>K</I>) for cumulative mite-days, where <I>K</I> is efficacy of control measure and <I>C</I> the management cost. This study demonstrated the seasonal dynamics of EILs for <I>T. urticae</I> on glasshouse cucumbers, suggesting that decision making for <I>T. urticae</I> management on cucumber needs to be seasonally different under the glasshouse condition.</P>

Bifenthrin과 Cyhexatin 저항성계통 점박이응애 (Tetranychus urticae)에 대한 살비제 혼합의 연합독작용

김상수,김도익,이승찬 한국곤충학회 1993 Entomological Research Vol.23 No.1

These studies were conducted to investigate the joint toxic action of mixtures of serveral acaricides including bifenthrin, cyhexatin, dicofol and ethion to the bifenthrin-and the cyhexatin resistant strain of Tetranychus urticae. The toxicity of acaricidal mixtures was greatly varied with the kind of acaricide combinations and their mixture ratios. With the bifenthrin resistant strain, the combinations of bifenthrin with each of the tested acaricides were synergized at the given mixture ratios. The higher synergistic action in the each combination was observed at 6 : 4 ratio with ethion, 8 : 2 ratio with dicofol, and cyhexatin. With the cyhexatin resistant strain, the maximum synergistic action was observed at 2 : 8 ratio of cyhexatin and dicofol. However, there were no synergistic actions in all cyhexatin mixtures with ethion and bifenthrin. Bifenthrin과 cyhexatin 도태저항성계통 점박이응애(Tetranychus urticae)에 대한 bifenthrin, cyhexatin, dicofol과 ethion을 상호혼합하여 연합독작용을 시험한 결과, 살비제 혼합에 의한 협력작용은 약제의 조합 또는 그들의 혼합비율에 따라 큰 차이를 보였다. Bifenthrin 도태저항성계통에 대해 bifenthrin과 조합한 공시약제는 모두 협력작용을 나타내어, ethion과의 조합에서는 6 : 4, dicofol, cyhexatin과의 조합에서는 8 : 2의 혼합비에서 최대의 협려효과를 보였다. Cyhexatin 도태저항성계통에 대해서는 cyhexatin과 dicofol을 조합하였을 때 2 : 8의 혼합비에서 최대의 협력효과를 나타내었고, cyhexatin과 ethion 또는 bifenthrin의 조합에서는 협력작용이 나타나지 않았다.

Transgenic Arabidopsis thaliana expressing hairpin RNA of coatomer subunit alpha gene is lethal to Tetranychus urticae

Vimal Kumar Dubey,Ung Gyu Lee,Si Hyeock Lee 한국응용곤충학회 2016 한국응용곤충학회 학술대회논문집 Vol.2016 No.10

Recently, RNA interference (RNAi) technology has been emerged as a potent tool for pest control strategy. Based on the previous studies on RNAi via leaf disc-mediated systemic delivery of dsRNA and in planta expression of hairpin RNA by agroinfiltration, the coatomer subunit alpha (COPA) gene has been found to be a crucial target for RNAi against Tetranychus urticae. In current study, transgenic plants of Arabidopsis thaliana expressing COPA hairpin RNA were generated by the floral dip method. Putative transgenic plants were screened by PCR and positive transformants were subjected to bioassay using age-synchronized and host-adapted T. urticae. T. urticae feeding on plants expressing dsRNA/siRNA showed more than 80% mortality as compared to the mites feeding on control plants at 6 days post-infestation. Our data shows that in planta expression of hairpin gene such as COPA may serve as an effective way for the control of this important pest in ornamental and economically important plants.

Agroinfiltration-based expression of hairpin RNA in soybean plants for RNA interference against <i>Tetranychus urticae</i>

Dubey, Vimal Kumar,Lee, Ung Gyu,Kwon, Deok Ho,Lee, Si Hyeock Elsevier 2017 Pesticide biochemistry and physiology Vol.142 No.-

<P>The coatomer subunit alpha (COPA) and aquaporin 9 (AQ9) genes from the two-spotted spider mite, Tetranychus urticae, were previously determined to exhibit RNA interference (RNAi)-based lethality when their double stranded RNAs were systemically delivered via multi-unit chambers (Kwon et al., 2016 [8]). In current study, the hairpin RNAs of the COPA and AQ9 were transiently expressed in soybean plants by agroinfiltration. When T. urticae was fed with the soybean plants agroinfiltrated with the COPA and AQ9 hairpin RNA cassettes, the cumulative mortality increased significantly at 6 days post-infestation. Quantitative PCR analysis revealed that the transcript level of both COPA and AQ9 was significantly reduced in T. urticae after 2 days post-infestation, thereby confirming that the significant increases in mortality resulted from the knockdown of COPA and AQ9 transcripts. Our findings demonstrate the utility of COPA and AQ9 as potential genes for plant host-mediated RNAi control of T. urticae. In addition, we proved the usefulness of agroinfiltration as a rapid validation tool for confirming the RNAi-based lethality of target genes against arthropod pests before producing transgenic plants as agroinfiltration requires less time and skill to validate transgene function. Furthermore, these findings prove the concept that hairpin RNA expressed in plant hosts can also induce RNAi and eventually kill T. urticae, a sap-sucking pest. (C) 2017 Elsevier Inc. All rights reserved.</P>