• Korean journal of applied entomology
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• v.35 no.3
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• pp.260-265
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• 1996

A field colony of the two-spotted spider mite, Tetranychus urticae Koch, was selected with tetradifon for 4 mousing whole-plant residual method. This strain showed 371-fold resistance to tetradifon. The log dosehatchability lines of $F_{1}$ eggs(RS cross; Td5female$\times$Smale, and SR cross; Sfemale$\times$Td5male) were closer to the line of the resistant colony than to that of the susceptible. These differences could be due to cytoplasmic inheritance or maternal effect. The estimate of dominance index (D) for the $F_{1}$ eggs of RS cross was 0.998 and that for $F_{1}$ eggs of SR cross was 0.262. This indicates that tetradifon resistance is completely dominant in RS cross and incompletely dominant in SR cross. Td5 strain exhibited high levels of resistance to clofentezine, benzoximate, and chlorfencon, and no cross resistance to fenazaquin, pyridaben, flufenoxuron, tebufenpyrad, and fenothiocarb.

• Korean journal of applied entomology
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• v.43 no.1
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• pp.43-48
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• 2004

Development of 3,700 folds resistance to etoxazole was found in the population of twospotted spider mite, Tetranychus urticae, collected from rose greenhouses in Buyo, Chungnam Provience in August 2000. This population was selected for 3yr with etoxazole to get 5,000,000 folds increase in resistance as compared to susceptible (S) strain. The etoxazole resistance was stablized for 16 months under the condition of no acaricide application. Inheritance and cross resistance in etoxazole to some acaricides of the etoxazole resistance strain (R) were investigated. There were differences of susceptibility in the etoxazole concentration-mortality relationships between $F_1$, $F_2$ progenies obtained from reciprocal cross with the S and R strains (R$_{♂}$${\times}$S$_{♂}$${\times}$R$_{♂}$). Degrees of dominance were 0.98 and 0.98 in $F_1$ and $F_2$ progenies of R$_{♂}$${\times}$S$_{♂}$, and -0.97 and -0.68 in $F_1$ and $F_2$ progenies of S$_{♀}$${\times}$R$_{♂}$ respectively. Inheritance in $F_1$ and $F_2$ progenies of R$_{♀}$${\times}$S$_{♂}$ were complete dominant. However $F_1$ and $F_2$ progenies of S$_{♀}$${\times}$R$_{♂}$ were incomplete recessive. These results suggest that inheritance of etoxazole resistance is controlled by a complete dominance. The R strain exhibited cross resistance to acequinocyl and emamectin benzoates in adult females, and milbemectin, amitraz and pyridaben in eggs. However they showed negatively correlated cross-resistance to bifenazate, a carbazate acaricide. These results may indicate bifenazate could be useful for the control of etoxazole resistant T. urticae population.

• Korean journal of applied entomology
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• v.44 no.2
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• pp.151-156
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• 2005

The development of resistance to bifenazate (resistance ratio of egg=40.3 folds) was found in population of the twospotted spider mite, Tetranychus urticae, collected from rose greenhouses in Chilgok, Gyeongbuk Province in December 2000. This population was selected for 4 years with bifenazate treatment (over 150 times), and showed 248.8 folds increase in resistance as compared to susceptible (S) strain. Inheritance of bifenazate resistant strain (R) and cross resistance of this strain to 9 acaricides were investigated. There were differences of susceptibility in the bifenazate concentration-mortality relationships in F1 progenies obtained from reciprocal cross with the S and R strain $(R{\times}S,\;S{\times}R)$. Degrees of dominance were 0.48 and 0.94 in adult females and eggs of $R{\times}S$ and -0.85 and -0.17 in adult females and eggs of $S{\times}R$, respectively. Inheritance type in the F1 progeny of $R{\times}S$ was incomplete dominant, and F1 progeny of $S{\times}R$ was incomplete recessive. These results suggest that inheritance of bifenazate resistance is controlled by a complete dominance. The R strain exhibited cross resistance to acequinocyl and fenpyroximate in adult females, and amitraz, emamectin benzoate, fenpyroximate, milbemectin, pyridaben and spirodiclofen in eggs. However they showed negatively correlated cross-resistance to emamectin benzoate and milbemectin in adult females, and abamectin in eggs.

• Korean journal of applied entomology
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• v.51 no.4
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• pp.357-364
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• 2012

This study was conducted to observe the influence of chemical pesticides and environmentally friendly agricultural materials (EFAMs) used in tomato cultivation on the pathogenicity of the entomopathogenic fungus, Beauveria bassiana. B. bassiana mycelium didn't grow on PDA media containing 13 fungicides including chlorothalonil and colonies were not formed on PDA media containing 12 fungicides. B. bassiana mycelium grew and colonies were formed on all PDA media containing insecticides and EFAMs, but mycelial growth and colony formation on most PDA media were significantly inhibited compared to the control. The insecticidal activity of B. bassiana against Trialeurodes vaporariorum was decreased when fungicides (polyoxin B, mandipropamid) and EFAMs containing sulfur were added, but insecticides (pyridaben, dinotefuran) and EFAMs originated from plant extracts did not have any influence on the insecticidal activity of B. bassiana. The pathogenicity of a mixture of B. bassiana and polyoxin B against T. vaporariorum was lower than that of B. bassiana alone under greenhouse conditions.

• Korean journal of applied entomology
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• v.34 no.1
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• pp.40-45
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• 1995

Eight field-collected populations of the two-spotted spider mites, Tetranychus urticae (Koch) from apple orchards of different geographical areas were tested for resistance to seven acaricides by leaf disk method in comparison with a susceptible strain. Marked regional variations of susceptibility were observed. Only low to moderate resistance to azocyclotin, fenpropathrin, propargite, and abamectin was obtained. However, high resistance to dicofol, fenpyroxymate, and pyridaen by eight field-collected populations was produced. Resistance to dicofol and fenpyroxymate was widespread. All of the strains tested were susceptible to one or more o the acaricides used. These results indicate that careful selection of the chemical used against any population of the two-spotted spider mite might result in satisfactory control.

• Korean Journal of Organic Agriculture
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• v.25 no.1
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• pp.149-159
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• 2017

This study was conducted to develop an organic control method of tobacco whitefly (Bemisia tabaci) by using cooking oil and yolk mixture (COY). Mortality rate against B. tabaci nymph on paprika leaf was 94.5% by COY treatment and it was not significantly different from that by pyridaben treatment. Mortality rate against B. tabaci nymph on tomato leaf was 41.4% by COY treatment and it is lower than that by neem extract. But mortality rates of B. tabaci adult by COY and neem extract were no significant differences. Oviposition of B. tabaci were decrease respectively 75.8% and 52.7% by COY on paprika and tomato leaves. In paprika and tomato greenhouses, damaged by B. tabaci, COY was sprayed twice and resulted in respectively 100% and 38% control values.

• The Korean Journal of Pesticide Science
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• v.17 no.3
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• pp.185-192
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• 2013

This study was performed to evaluate the spray toxicity and leaf residual toxicity of 52 kinds of insecticides registered for strawberry against adult honeybee Apis mellifera. According to the IOBC standard, the acute toxicity by spraying showed below 30% was classified as non-toxic. Among tested insecticides, 32 insecticides (flonicamid, lufenuron, novaluron, three kinds of acetamiprid, thiacloprid, milbemectin, acequinocyl, TBI-1, two kinds of chlorfenapyr, chlorfluazuron, cyenopyrafen, cyfumetofen, etoxazole, fenpyroximate, flubendiamide, flufenoxuron, hexythiazox, metaflumizone, two kinds of methoxyfenozide, DBB-2032, pyridalyl, spiromesifen, tebufenpyrad, teflubenzuron, acetamiprid + methoxyfenozide, acrinathrin + spiromesifen, bifenazate + spiromesifen, cyenopyrafen + flufenoxuron) did not show any toxic effect, it is thought to be safe. And the others (20 insecticides) showed higher toxicity to honeybee. Insecticides which showed acute toxicity higher than 90% was selected and tested the residual toxicity. All insecticides except emamectin benzoate EC, and indoxacarb SC showed 100% mortality at one day after treatment (DAT). However, the toxicities of emamectin benzoate, indoxacarb SC, and abamectin did not show until 3, 7, 14 DAT, respectively. Nine insecticides such as indoxacarb WP, thiamethoxam WG, abamectin + chlorantraniliprole SC, acetamiprid + etofenprox WP, acetamiprid + indoxacarb WP, bifenthrin + clothianidin SC, bifenthrin + imidacloprid WP, bifenazate + pyridaben SC, chlorfenapyr + clothianidin SC showed over 90% residual toxicity until 31 Day. In pouring treatment, thiamethoxam WG showed 76.9% mortality at 28 DAT and 50.0% mortality at 31 DAT. After 35 days, thiamethoxam WG showed no effect to honeybee. Bifenthrin + clothianidin SC and tefluthrin + thiamethoxam GR showed 57.1 and 80.0% mortality at 24 DAT, respectively. In spraying treatment, thiamethoxam WG and bifenthrin+clothianidin SC showed very high residual toxicity with 100% mortality in thirty-five DAT. After spraying treatment with thiamethoxam WG, bifenthrin+clothianidin SC, bifenthrin + imidacloprid WP, thiamethoxam WG showed 100% residual toxicity until 21 DAT and there was no activity after 28 DAT. Bifenthrin+clothianidin SC and bifenthrin+imidacloprid WP showed very high residual toxicity until 49 DAT.

• The Korean Journal of Pesticide Science
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• v.11 no.2
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• pp.125-130
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• 2007

The development of resistance to acequinocyl was found in the population of the twospotted spider mite, Tetranychus urticae, collected from rose greenhouses in Gimhae, Gyeongnam province in January 2001. This pest is reared on 5 years treated with acequinocyl (over 200 times), and increased 87.8 folds in resistance as compared to susceptible strain (S). Inheritance of acequinocyl resistant strain (R) and cross resistance of this strain to 8 acaricides against T. urticae adults and eggs was investigated. There were differences of susceptibility in the acequinocyl concentration-mortality relationships in $F_1$ progenies obtained from reciprocal cross with the S and R strain ($S(female){\times}R(male)$, $R(female){\times}S(male)$). Degrees of dominance were -0.75, -0.57 in $F_1$ progenies of adult and egg of $S(female){\times}R(male)$. Inheritance in $F_1$ progenies of $S(female){\times}R(male)$ was incomplete recessive. Degree of dominance were 0.81, 0.45 in $F_1$ progenies of adult and egg of $R(female){\times}S(male)$, respectively. These results suggest that inheritance of acequinocyl resistance is controlled by a complete dominance. The R strain exhibited cross resistance of 1.1 and 0.9 fold to amitraz, bifenazate, and negatively correlated cross resistance of 0.08 fold to emamectin benzoate in adult females. The R strain showed cross resistance of 37.7, 14.0, and 26.2 fold to amitraz, milbemectin and spriodiclofen in eggs, respectively. Particularly it showed high levels of cross-resistance to pyridaben with 6538.3 fold. These chemicals showed negatively correlated cross-resistance exhibited 0.4, 0.3, and 0.2 fold to ahamectin, bifenazate, and emamectin benzoate in eggs.

• Korean journal of applied entomology
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• v.36 no.1
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• pp.111-117
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• 1997

Occurrence status of Tetranychus viennensis Zacher was investigated in Kyonghuk province. Its ecological studies were carried out and chemical control efficacy against females and eggs was examined. And the results ohtained are as follows. T. viennensis occurred from mid April through mid November with the peak time in June on cherry tree. Population level of T. viennensis was varied from 0 to 160 individuals per 100 peach leaves in different peach orchards, and its occurrence rate was 35% out of 20 ochards. However no T. viennensis was observed from 25 apple orchards in 5 districts of Kyongbuk province. Overwintering stage of T. viennensis females appeared in mid October, and most of them moved into under the rough hark in early November. The overwintered adult females moved out from the rough bark to leaves in early April. Mortality during overwintering was about 55%. Under four constant temperatures of 16, 19, 22, 25$^{\circ}$C. egg periods were 14. 3, 9.2, 6.8, and 4.0 days ; larva -nymph periods were 20.2, 13.9, 8.7, and 6.6 days. Female longevity was 67. 7, 60.7, 46.4, and 34.0 days : mean tota: fecundities per female were 21.2, 44.3, 54.4, and 64.7 eggs. Some acaricides, azocyclotin, pyridaben, propargite, tehufenpyrad and fenpyroximate were highly effective against females, while hexythiazox and clofentezine showed very low control effect from 3.6 to 14.4%. Whereas, all of 7 acaricides tested highly effective against the eggs.