Effect of cypermethrin on the control of lesser mealworm (Alphitobius diaperinus) and broiler performance

ABSTRACT: This study analysed the effectiveness of using different levels of a product based on 6% cypermethrin and 2% citronella on broiler production and control the lesser mealworm (Alphitobius diaperinus). A total of 648 one-day-old chicks (Cobb®) which were allocated to one of three treatments (no application of the commercial product - control, and two concentrations of the product 2.00 and 3.33g/m2) in eight replicates with 27 birds each. The commercial product, which was based on cypermethrin was applied in the chambers with an atomizer. The lesser mealworm population was sampled weekly (1, 7, 14, 21, 28, 35 and 42 days of the experiment) using traps, at three points (front, middle and back) inside the pen. The performance, carcass and cut yields were evaluated. At 21, 28, 35 and 42 days of the experiment, the number of lesser mealworm adults and larvae was lower in the treatment groups involving 2.00 and 3.33g/m2 of the product than in the control group. On the first and 14th days of the study, the number of lesser mealworms adults was lower in the group treated with 3.33g/m2 of the product compared to the control group, although the results did not differ statistically from those obtained with 2.00g/m2 of the product. In conclusion, the application of the commercial product at both concentrations (2.00 and 3.33g/m2) was effective in combating Alphitobius diaperinus adults and larvae, and the performance was not influenced by treatments.

RESUMO: Este estudo analisou a eficácia do uso de diferentes níveis de um produto à base de cipermetrina a 6% e citronela a 2%, na produção de frangos de corte e no controle do cascudinho (Alphitobius diaperinus). Um total de 648 pintos de um dia de idade (Cobb®) foram distribuídos em três câmaras com os tratamentos (sem aplicação do produto comercial - controle, e duas concentrações do produto comercial - 2,00 e 3,33g/m2) em oito repetições com 27 aves cada. O produto comercial a base de cipermetrina foi aplicado nas câmaras com um atomizador. A população de cascudinho foi amostrada semanalmente (1, 7, 14, 21, 28, 35 e 42 dias do experimento) usando armadilhas, em três pontos (frente, meio e fundo) de cada parcela. Foram avaliados o desempenho, rendimentos de carcaça e cortes. Aos 21, 28, 35 e 42 dias do experimento, o número de adultos e larvas de cascudinho foi menor nos grupos de tratamento envolvendo 2,00 e 3,33g/m2 do produto quando comparado ao grupo controle. No primeiro e no 14º dia do estudo, o número de cascudinhos adultos foi menor no grupo tratado com 3,33g/m2 do produto em comparação ao grupo controle, embora os resultados não tenham diferido estatisticamente daqueles obtidos com 2,00g/m2 do produto. A conversão alimentar de 1 a 21 dias de idade foi significativa, com os melhores resultados para essa variável quando aplicado 3,33g do produto por metro quadrado e no tratamento controle. Em conclusão, a aplicação do produto comercial em ambas as concentrações (2,00 e 3,33g/m2) foi eficaz no combate a adultos e larvas de Alphitobius diaperinus e, não influenciou o desempenho.

Effect of cypermethrin on the control of lesser mealworm (Alphitobius diaperinus) and broiler performance / Efeito da cipermetrina no controle de cascudinho (Alphitobius diaperinus) sobre o desempenho de frangos de corte

This study analysed the effectiveness of using different levels of a product based on 6% cypermethrin and 2% citronella on broiler production and control the lesser mealworm (Alphitobius diaperinus). A total of 648 one-day-old chicks (Cobb®) which were allocated to one of three treatments (no application of the commercial product - control, and two concentrations of the product 2.00 and 3.33g/m2) in eight replicates with 27 birds each. The commercial product, which was based on cypermethrin was applied in the chambers with an atomizer. The lesser mealworm population was sampled weekly (1, 7, 14, 21, 28, 35 and 42 days of the experiment) using traps, at three points (front, middle and back) inside the pen. The performance, carcass and cut yields were evaluated. At 21, 28, 35 and 42 days of the experiment, the number of lesser mealworm adults and larvae was lower in the treatment groups involving 2.00 and 3.33g/m2 of the product than in the control group. On the first and 14th days of the study, the number of lesser mealworms adults was lower in the group treated with 3.33g/m2 of the product compared to the control group, although the results did not differ statistically from those obtained with 2.00g/m2 of the product. In conclusion, the application of the commercial product at both concentrations (2.00 and 3.33g/m2) was effective in combating Alphitobius diaperinus adults and larvae, and the performance was not influenced by treatments.(AU)

Este estudo analisou a eficácia do uso de diferentes níveis de um produto à base de cipermetrina a 6% e citronela a 2%, na produção de frangos de corte e no controle do cascudinho (Alphitobius diaperinus). Um total de 648 pintos de um dia de idade (Cobb®) foram distribuídos em três câmaras com os tratamentos (sem aplicação do produto comercial - controle, e duas concentrações do produto comercial - 2,00 e 3,33g/m2) em oito repetições com 27 aves cada. O produto comercial a base de cipermetrina foi aplicado nas câmaras com um atomizador. A população de cascudinho foi amostrada semanalmente (1, 7, 14, 21, 28, 35 e 42 dias do experimento) usando armadilhas, em três pontos (frente, meio e fundo) de cada parcela. Foram avaliados o desempenho, rendimentos de carcaça e cortes. Aos 21, 28, 35 e 42 dias do experimento, o número de adultos e larvas de cascudinho foi menor nos grupos de tratamento envolvendo 2,00 e 3,33g/m2 do produto quando comparado ao grupo controle. No primeiro e no 14º dia do estudo, o número de cascudinhos adultos foi menor no grupo tratado com 3,33g/m2 do produto em comparação ao grupo controle, embora os resultados não tenham diferido estatisticamente daqueles obtidos com 2,00g/m2 do produto. A conversão alimentar de 1 a 21 dias de idade foi significativa, com os melhores resultados para essa variável quando aplicado 3,33g do produto por metro quadrado e no tratamento controle. Em conclusão, a aplicação do produto comercial em ambas as concentrações (2,00 e 3,33g/m2) foi eficaz no combate a adultos e larvas de Alphitobius diaperinus e, não influenciou o desempenho.(AU)

Effect of cypermethrin on the control of lesser mealworm (Alphitobius diaperinus) and broiler performance / Efeito da cipermetrina no controle de cascudinho (Alphitobius diaperinus) sobre o desempenho de frangos de corte

This study analysed the effectiveness of using different levels of a product based on 6% cypermethrin and 2% citronella on broiler production and control the lesser mealworm (Alphitobius diaperinus). A total of 648 one-day-old chicks (Cobb®) which were allocated to one of three treatments (no application of the commercial product - control, and two concentrations of the product 2.00 and 3.33g/m2) in eight replicates with 27 birds each. The commercial product, which was based on cypermethrin was applied in the chambers with an atomizer. The lesser mealworm population was sampled weekly (1, 7, 14, 21, 28, 35 and 42 days of the experiment) using traps, at three points (front, middle and back) inside the pen. The performance, carcass and cut yields were evaluated. At 21, 28, 35 and 42 days of the experiment, the number of lesser mealworm adults and larvae was lower in the treatment groups involving 2.00 and 3.33g/m2 of the product than in the control group. On the first and 14th days of the study, the number of lesser mealworms adults was lower in the group treated with 3.33g/m2 of the product compared to the control group, although the results did not differ statistically from those obtained with 2.00g/m2 of the product. In conclusion, the application of the commercial product at both concentrations (2.00 and 3.33g/m2) was effective in combating Alphitobius diaperinus adults and larvae, and the performance was not influenced by treatments.(AU)

Este estudo analisou a eficácia do uso de diferentes níveis de um produto à base de cipermetrina a 6% e citronela a 2%, na produção de frangos de corte e no controle do cascudinho (Alphitobius diaperinus). Um total de 648 pintos de um dia de idade (Cobb®) foram distribuídos em três câmaras com os tratamentos (sem aplicação do produto comercial - controle, e duas concentrações do produto comercial - 2,00 e 3,33g/m2) em oito repetições com 27 aves cada. O produto comercial a base de cipermetrina foi aplicado nas câmaras com um atomizador. A população de cascudinho foi amostrada semanalmente (1, 7, 14, 21, 28, 35 e 42 dias do experimento) usando armadilhas, em três pontos (frente, meio e fundo) de cada parcela. Foram avaliados o desempenho, rendimentos de carcaça e cortes. Aos 21, 28, 35 e 42 dias do experimento, o número de adultos e larvas de cascudinho foi menor nos grupos de tratamento envolvendo 2,00 e 3,33g/m2 do produto quando comparado ao grupo controle. No primeiro e no 14º dia do estudo, o número de cascudinhos adultos foi menor no grupo tratado com 3,33g/m2 do produto em comparação ao grupo controle, embora os resultados não tenham diferido estatisticamente daqueles obtidos com 2,00g/m2 do produto. A conversão alimentar de 1 a 21 dias de idade foi significativa, com os melhores resultados para essa variável quando aplicado 3,33g do produto por metro quadrado e no tratamento controle. Em conclusão, a aplicação do produto comercial em ambas as concentrações (2,00 e 3,33g/m2) foi eficaz no combate a adultos e larvas de Alphitobius diaperinus e, não influenciou o desempenho.(AU)

Synergistic potential of dillapiole-rich essential oil with synthetic pyrethroid insecticides against fall armyworm / Potencial sinérgico do óleo essencial rico em dilapiol para inseticidas piretroides sintéticos frente à lagarta-do-cartucho

The objective of this study was to evaluate the synergy and response homogeneity of the Spodoptera frugiperda larvae population to the Piper aduncum essential oil in combination with pyrethroid insecticides (alpha-cypermethrin, beta-cypermethrin, fenpropathrin, and gamma-cyhalothrin) compared to piperonylbutoxide (PBO) as positive control. Synergism (SF) comparisons were obtained using lethal concentration (LC50) and lethal dose (LD50) ratios of insecticides individually and in their respective synergistic combinations with essential oil and PBO. Dose/concentration-mortality slope curves were used to establish relative toxicity increase promoted by synergism. They also determined homogeneity response. Residual contact revealed significant potentiation for commercial insecticides formulated with beta-cypermethrin (SF=9.05-0.5) and fenpropathrin (SF=34.05-49.77) when combined with the P. aduncum essential oil. For topical contact, significant potentiation occurred only for alpha-cypermethrin (SF=7.55-3.68), fenpropathrin (SF=3.37-1.21), and gamma-cyhalothrin (SF=5.79-10.48) insecticides when combined with essential oil. With the exception of fenpropathrin and gamma-cyhalothrin, insecticides synergistic combinations presented homogeneous response by topical as well as residual contact at least with essential oil. The SF significance values of the P. aduncum essential oil combined with alpha-cypermethrin, beta-cypermethrin, fenpropathrin, and gamma-cyhalothrin insecticides indicated potential for this oil to be used as an alternative to PBO.(AU)

O objetivo deste trabalho foi avaliar a sinergia e homogeneidade de resposta de lagartas de Spodoptera frugiperda ao óleo essencial de Piper aduncum, em combinações com inseticidas do grupo dos piretroides: alfa-Cipermetrina, beta-Cipermetrina, Fenpropatrina e gama-Cialotrina, em comparação ao butóxido de piperonila (PBO controle positivo). Por meio da relação das CL50 e DL50 dos inseticidas tomados isoladamente e de suas respectivas combinações sinérgicas com o óleo essencial e o PBO, foram obtidos os fatores de sinergismo (FS) para comparação entre si. O coeficiente angular das curvas de dose/concentração-mortalidade foi utilizado no estabelecimento do aumento de toxicidade relativa, promovida pelos sinérgicos e determinação da homogeneidade de resposta. Por contato residual, evidenciou-se significativa potencialização dos inseticidas comerciais formulados com beta-Cipermetrina (FS=9,05-0,5) e Fenpropatrina (FS=34,05-49,77), quando combinados com o óleo essencial de P. aduncum. Já por contato tópico, ocorreu significativa potencialização somente dos inseticidas alfa-Cipermetrina (FS=7,55-3,68), Fenpropatrina (FS=3,37-1,21) e gama-Cialotrina (FS=5,79-10,48) quando em combinação com o óleo essencial. Com exceção da Fenpropatrina e gama-Cialotrina, as demais combinações sinérgicas apresentaram homogeneidade de resposta tanto por contato tópico como residual, para pelo menos uma combinação sinérgica com o óleo essencial de P. aduncum. A significância dos valores do FS das combinações do óleo essencial de P. aduncum com os inseticidas a base de alfa-Cipermetrina, beta-Cipermetrina, Fenpropatrina e gama-Cialotrina pode indicar que esse óleo essencial é uma alternativa ao PBO.(AU)

Evaluation of the efficacy of cypermethrin and amitraz against Rhipicephalus (Boophilus) microplus, in the State of Pernambuco, Brazil / Avaliação da eficácia de cipermetrina e amitraz contra Rhipicephalus (Boophilus) microplus no estado de Pernambuco, Brasil

The Rhipicephalus (Boophilus ) microplus is an important tick species which affect bovines in tropical areas. Its control is based on the use of chemical acaricides, but the frequent use of these substances has been conducted to the development of tick resistance. The aim of this study was to assess the efficacy of cypermethrin and amitraz against R. (B. ) microplus collected of bovines from different municipalities of the state of Pernambuco. From August 2009 to July 2011, engorged females were collected and subjected to the "Adult Immersion Test" in order to evaluate the efficacy of cypermethrin and amitraz. The results indicate that populations of R. (B. ) microplus from Pernambuco present resistance to acaricides (i.e., cypermethrin and amitraz). In this study, a single population (Brejo da Madre de Deus) was susceptible to cypermethrin, whereas two (Timbaúba and Limoeiro) were susceptible to amitraz. Data herein reported follow a pattern observed in other regions of Brazil and alert to the fact that alternative measures of control should be implemented in this area studied.(AU)

Rhipicephalus (Boophilus ) microplus é uma importante espécie que acomete bovinos em áreas tropicais. O controle desse carrapato se baseia no uso de acaricidas químicos, mas a utilização frequente dessas substâncias tem conduzido ao desenvolvimento de resistência. O objetivo deste estudo foi avaliar a eficácia da cipermetrina e do amitraz contra R. (B. ) microplus coletadas de bovinos de diferentes municípios do estado de Pernambuco. De agosto de 2009 a julho de 2011, as fêmeas ingurgitadas foram coletadas e submetidas ao Adult Immersion Test , a fim de avaliar a eficácia de cipermetrina e amitraz. Os resultados indicam que as populações de R. (B. ) microplus de Pernambuco apresentaram resistência aos acaricidas (cipermetrina e amitraz). Neste estudo, uma única população (Brejo da Madre de Deus) foi suscetível à cipermetrina, enquanto duas (Timbaúba e Limoeiro) foram sensíveis ao amitraz. Os dados aqui relatados seguem um padrão observado em outras regiões do Brasil e alertam para o fato de que as medidas alternativas de controle devem ser implementadas na área estudada.(AU)

Evaluation of the efficacy of cypermethrin and amitraz against Rhipicephalus (Boophilus) microplus, in the State of Pernambuco, Brazil / Avaliação da eficácia de cipermetrina e amitraz contra Rhipicephalus (Boophilus) microplus no estado de Pernambuco, Brasil

The Rhipicephalus (Boophilus) microplus is an important tick species which affect bovines in tropical areas. Its control is based on the use of chemical acaricides, but the frequent use of these substances has been conducted to the development of tick resistance. The aim of this study was to assess the efficacy of cypermethrin and amitraz against R. (B.) microplus collected of bovines from different municipalities of the state of Pernambuco. From August 2009 to July 2011, engorged females were collected and subjected to the Adult Immersion Test in order to evaluate the efficacy of cypermethrin and amitraz. The results indicate that populations of R. (B.) microplus from Pernambuco present resistance to acaricides (i.e., cypermethrin and amitraz). In this study, a single population (Brejo da Madre de Deus) was susceptible to cypermethrin, whereas two (Timbaúba and Limoeiro) were susceptible to amitraz. Data herein reported follow a pattern observed in other regions of Brazil and alert to the fact that alternative measures of control should be implemented in this area studied.

Rhipicephalus (Boophilus) microplus é uma importante espécie que acomete bovinos em áreas tropicais. O controle desse carrapato se baseia no uso de acaricidas químicos, mas a utilização frequente dessas substâncias tem conduzido ao desenvolvimento de resistência. O objetivo deste estudo foi avaliar a eficácia da cipermetrina e do amitraz contra R. (B.) microplus coletadas de bovinos de diferentes municípios do estado de Pernambuco. De agosto de 2009 a julho de 2011, as fêmeas ingurgitadas foram coletadas e submetidas ao Adult Immersion Test, a fim de avaliar a eficácia de cipermetrina e amitraz. Os resultados indicam que as populações de R. (B.) microplus de Pernambuco apresentaram resistência aos acaricidas (cipermetrina e amitraz). Neste estudo, uma única população (Brejo da Madre de Deus) foi suscetível à cipermetrina, enquanto duas (Timbaúba e Limoeiro) foram sensíveis ao amitraz. Os dados aqui relatados seguem um padrão observado em outras regiões do Brasil e alertam para o fato de que as medidas alternativas de controle devem ser implementadas na área estudada.

Evaluation of the efficacy of cypermethrin and amitraz against Rhipicephalus (Boophilus) microplus, in the State of Pernambuco, Brazil

ABSTRACT: The Rhipicephalus (Boophilus )microplus is an important tick species which affect bovines in tropical areas. Its control is based on the use of chemical acaricides, but the frequent use of these substances has been conducted to the development of tick resistance. The aim of this study was to assess the efficacy of cypermethrin and amitraz against R. (B. )microplus collected of bovines from different municipalities of the state of Pernambuco. From August 2009 to July 2011, engorged females were collected and subjected to the "Adult Immersion Test" in order to evaluate the efficacy of cypermethrin and amitraz. The results indicate that populations of R. (B. )microplus from Pernambuco present resistance to acaricides (i.e., cypermethrin and amitraz). In this study, a single population (Brejo da Madre de Deus) was susceptible to cypermethrin, whereas two (Timbaúba and Limoeiro) were susceptible to amitraz. Data herein reported follow a pattern observed in other regions of Brazil and alert to the fact that alternative measures of control should be implemented in this area studied.

RESUMO: Rhipicephalus (Boophilus )microplus é uma importante espécie que acomete bovinos em áreas tropicais. O controle desse carrapato se baseia no uso de acaricidas químicos, mas a utilização frequente dessas substâncias tem conduzido ao desenvolvimento de resistência. O objetivo deste estudo foi avaliar a eficácia da cipermetrina e do amitraz contra R. (B. )microplus coletadas de bovinos de diferentes municípios do estado de Pernambuco. De agosto de 2009 a julho de 2011, as fêmeas ingurgitadas foram coletadas e submetidas ao Adult Immersion Test , a fim de avaliar a eficácia de cipermetrina e amitraz. Os resultados indicam que as populações de R. (B. )microplus de Pernambuco apresentaram resistência aos acaricidas (cipermetrina e amitraz). Neste estudo, uma única população (Brejo da Madre de Deus) foi suscetível à cipermetrina, enquanto duas (Timbaúba e Limoeiro) foram sensíveis ao amitraz. Os dados aqui relatados seguem um padrão observado em outras regiões do Brasil e alertam para o fato de que as medidas alternativas de controle devem ser implementadas na área estudada.

Evaluation of the efficacy of cypermethrin and amitraz against Rhipicephalus (Boophilus) microplus, in the State of Pernambuco, Brazil / Avaliação da eficácia de cipermetrina e amitraz contra Rhipicephalus (Boophilus) microplus no estado de Pernambuco, Brasil

The Rhipicephalus (Boophilus) microplus is an important tick species which affect bovines in tropical areas. Its control is based on the use of chemical acaricides, but the frequent use of these substances has been conducted to the development of tick resistance. The aim of this study was to assess the efficacy of cypermethrin and amitraz against R. (B.) microplus collected of bovines from different municipalities of the state of Pernambuco. From August 2009 to July 2011, engorged females were collected and subjected to the Adult Immersion Test in order to evaluate the efficacy of cypermethrin and amitraz. The results indicate that populations of R. (B.) microplus from Pernambuco present resistance to acaricides (i.e., cypermethrin and amitraz). In this study, a single population (Brejo da Madre de Deus) was susceptible to cypermethrin, whereas two (Timbaúba and Limoeiro) were susceptible to amitraz. Data herein reported follow a pattern observed in other regions of Brazil and alert to the fact that alternative measures of control should be implemented in this area studied.(AU)

Rhipicephalus (Boophilus) microplus é uma importante espécie que acomete bovinos em áreas tropicais. O controle desse carrapato se baseia no uso de acaricidas químicos, mas a utilização frequente dessas substâncias tem conduzido ao desenvolvimento de resistência. O objetivo deste estudo foi avaliar a eficácia da cipermetrina e do amitraz contra R. (B.) microplus coletadas de bovinos de diferentes municípios do estado de Pernambuco. De agosto de 2009 a julho de 2011, as fêmeas ingurgitadas foram coletadas e submetidas ao Adult Immersion Test, a fim de avaliar a eficácia de cipermetrina e amitraz. Os resultados indicam que as populações de R. (B.) microplus de Pernambuco apresentaram resistência aos acaricidas (cipermetrina e amitraz). Neste estudo, uma única população (Brejo da Madre de Deus) foi suscetível à cipermetrina, enquanto duas (Timbaúba e Limoeiro) foram sensíveis ao amitraz. Os dados aqui relatados seguem um padrão observado em outras regiões do Brasil e alertam para o fato de que as medidas alternativas de controle devem ser implementadas na área estudada.(AU)

Biodegradation of cypermethrin by immobilized cells of Micrococcus sp. strain CPN 1

Pyrethroid pesticide cypermethrin is a environmental pollutant because of its widespread use, toxicity and persistence. Biodegradation of such chemicals by microorganisms may provide an cost-effective method for their detoxification. We have investigated the degradation of cypermethrin by immobilized cells of Micrococcus sp. strain CPN 1 in various matrices such as, polyurethane foam (PUF), polyacrylamide, sodium alginate and agar. The optimum temperature and pH for the degradation of cypermethrin by immobilized cells of Micrococcus sp. were found to be 30 °C and 7.0, respectively. The rate of degradation of 10 and 20 mM of cypermethrin by freely suspended cells were compared with that of immobilized cells in batches and semi-continuous with shaken cultures. PUF-immobilized cells showed higher degradation of cypermethrin (10 mM and 20 mM) than freely suspended cells and cells immobilized in other matrices. The PUF-immobilized cells of Micrococcus sp. strain CPN 1 were retain their degradation capacity. Thus, they can be reused for more than 32 cycles, without losing their degradation capacity. Hence, the PUF-immobilized cells of Micrococcus sp. could potentially be used in the bioremediation of cypermethrin contaminated water..(AU)

Evaluation of the efficacy of cypermethrin and amitraz against Rhipicephalus (Boophilus) microplus, in the State of Pernambuco, Brazil

ABSTRACT: The Rhipicephalus (Boophilus )microplus is an important tick species which affect bovines in tropical areas. Its control is based on the use of chemical acaricides, but the frequent use of these substances has been conducted to the development of tick resistance. The aim of this study was to assess the efficacy of cypermethrin and amitraz against R. (B. )microplus collected of bovines from different municipalities of the state of Pernambuco. From August 2009 to July 2011, engorged females were collected and subjected to the "Adult Immersion Test" in order to evaluate the efficacy of cypermethrin and amitraz. The results indicate that populations of R. (B. )microplus from Pernambuco present resistance to acaricides (i.e., cypermethrin and amitraz). In this study, a single population (Brejo da Madre de Deus) was susceptible to cypermethrin, whereas two (Timbaúba and Limoeiro) were susceptible to amitraz. Data herein reported follow a pattern observed in other regions of Brazil and alert to the fact that alternative measures of control should be implemented in this area studied.

RESUMO: Rhipicephalus (Boophilus )microplus é uma importante espécie que acomete bovinos em áreas tropicais. O controle desse carrapato se baseia no uso de acaricidas químicos, mas a utilização frequente dessas substâncias tem conduzido ao desenvolvimento de resistência. O objetivo deste estudo foi avaliar a eficácia da cipermetrina e do amitraz contra R. (B. )microplus coletadas de bovinos de diferentes municípios do estado de Pernambuco. De agosto de 2009 a julho de 2011, as fêmeas ingurgitadas foram coletadas e submetidas ao Adult Immersion Test , a fim de avaliar a eficácia de cipermetrina e amitraz. Os resultados indicam que as populações de R. (B. )microplus de Pernambuco apresentaram resistência aos acaricidas (cipermetrina e amitraz). Neste estudo, uma única população (Brejo da Madre de Deus) foi suscetível à cipermetrina, enquanto duas (Timbaúba e Limoeiro) foram sensíveis ao amitraz. Os dados aqui relatados seguem um padrão observado em outras regiões do Brasil e alertam para o fato de que as medidas alternativas de controle devem ser implementadas na área estudada.

NANOTECNOLOGIA APLICADA À ELABORAÇÃO DE CARRAPATICIDAS SINTÉTICOS ASSOCIADOS A COMPOSTOS VEGETAIS PARA O CONTROLE DE Rhipicephalus (Boophilus) microplus

Rhipicephalus microplus causa quedas na produção e consequentes prejuízos econômicos à pecuária. A resistência aos acaricidas e o risco da presença de resíduos nos alimentos de origem animal têm impulsionado a busca por novas alternativas de controle. Vários compostos vegetais possuem potencial acaricida/repelente, porém, possuem limitações em sua aplicação. Nanocarreadores podem proteger esses compostos, aumentar sua solubilidade aquosa e biodisponibilidade, além de reduzir possíveis efeitos tóxicos. Dessa forma, o objetivo desse estudo foi desenvolver formulações carrapaticidas a partir de Nanopartículas Lipídicas Sólidas (NLS), Carreadores Lipídicos Nanoestruturados (CLN) e Nanopartículas de Zeína (NZ), associados à cipermetrina, clorpirifós e um composto vegetal (citral, mentol ou limoneno), caracterizar esses sistemas nanocarreadores e verificar sua atuação contra larvas e fêmeas ingurgitadas de R. microplus. Nove formulações foram desenvolvidas e caracterizadas por Dynamic Light Scattering (DLS) e Nanoparticle Tracking Analysis (NTA). As formulações 1 (NLS+cip+clo+citral), 2 (NLS+cip+clo+mentol), 3 (NLS+cip+clo+limoneno), 4 (CLN+cip+clo+citral), 5 (CLN+cip+clo+mentol) e 6 (CLN+cip+clo+limoneno) obtiveram médias de diâmetro de 286 a 304 nm; polidispersão de 0,16 a 0,18; potencial zeta de -15,8 a -20 mV, concentração de 3,37 ± 0,24 x 1013 a 5,44 ± 0,18 x 1013 partículas/mL; e Eficiência de Encapsulação (EE) > 98,01% para todos os princípios ativos, enquanto, para os mesmos parâmetros, as formulações de zeína NZ-1 (NZ+cip+clo+citral), NZ-2 (NZ+cip+clo+mentol) e NZ-3 (NZ+cip+clo+limoneno) obtiveram, respectivamente, valores médios de: 282,18 a 290,64 nm; 0,24 a 0,25; -3,35 a -6,10 mV; e concentração de 2,73 ± 2,67 x 1013 a 3,20 ± 3,03 x 1013 partículas/mL e EE > 96%. Todas as formulações foram avaliadas quanto ao seu potencial acaricida e comparadas com controles positivo (Colosso®) e negativos (água destilada; e nanopartículas sem princípio ativo). Na avaliação das formulações de nanocarreadores lipídicos, pelo Teste de Pacote de Larvas (TPL), os controles negativos não ocasionaram mortalidade das larvas, enquanto o controle positivo, avaliado na concentração de 0,512 mg.mL-1, causou 100% de mortalidade. As formulações de NLS 1, 2, 3 e de CLN 4, 5 e 6 foram avaliadas de 0,004 a 0,466 mg.mL-1. Na concentração de 0,007 mg.mL-1 atingiram 90,4, 75,9, 93,8, 100, 95,1, 72,7 % de mortalidade. Com excessão da 4, para a qual não foi possível determinar concentrações letais (CL), as formulações 1, 2, 3, 5 e 6 resultaram em CL50 e CL90 de: 0,0033 e 0,0072; 0,0054 e 0,0092; 0,0040 e 0,0081; 0,0023 e 0,0054; 0,0055 e 0,0094 mg.mL-1, respectivamente. Em relação às nanoformulações de zeína avaliadas pelo TPL, os controles negativos também não ocasionaram mortalidade das larvas, entretanto, o controle positivo (avaliado de 0,004 a 0,512 mg.mL-1), resultou em mortalidade de larvas > 71,9% na concentração de 0,064 mg.mL-1, enquanto as formulações de zeína (avaliadas de 0,004 a 0,466 mg.mL-1) ocasionaram mortalidade > 80 % na concentração de 0,029 mg.mL-1. Essas formulações NZ-1 (NZ+cip+clo+citral), NZ-2 (NZ+cip+clo+mentol) e NZ-3 (NZ+cip+clo+limoneno) ainda resultaram em altas taxas de mortalidade de larvas em menores concentrações, com CL50 e CL90 de: 0,0136 e 0,0352; 0,0115 e 0,0386; 0,0117 e 0,0301 mg.mL-1, respectivamente, e 0,0319 e 0,1028 mg.mL-1,vi respectivamente, para o controle positivo). As formulações de zeína foram também avaliadas pelo Teste de Imersão de Adultos (TIA) e as formulações NZ-1, NZ-2 e NZ-3 obtiveram, respectivamente: 50,2, 40,5 e 60,1% de eficácia sobre fêmeas ingurgitadas na concentração de 0,466 mg.mL-1, enquanto o controle positivo resultou em 39,4% de eficácia a 0,512 mg.mL-1. As formulações de zeína ainda apresentaram uma alta atividade residual, embora menor do que a do controle positivo. Esse estudo demonstrou que foi possível encapsular os princípios ativos priorizados e caracterizar os sistemas carreadores. Todas as nanoformulações foram capazes de proteger os princípios ativos contra a degradação em solução, o que é uma característica de estabilidade visada para produtos carrapaticidas comerciais. Dessa forma, nanoformulações podem ser uma alternativa para o desenvolvimento de novos biocarrapaticidas com menor quantidade de princípios ativos, visando-se promover um controle parasitário mais seguro, com menor risco de presença de resíduos nos alimentos de origem animal e no ambiente.

Rhipicephalus microplus causes declines in cattle production and consequent damage to livestock. The resistance of ticks and the risk of the presence of residues in food of animal origin have driven the search for new control alternatives. Several plant compounds have an acaricidal/repellent potential, however, they have limitations in their application. Nanocarriers can protect these compounds, increase their aqueous solubility and bioavailability, and reduce possible toxic effects. Thus, the objective of this study was to develop acaricide formulations from Solid Lipid Nanoparticles (NLS), Nanostructured Lipid Carriers (CLN) and Zein Nanoparticles (NZ), associated with cypermethrin (cip), chlorpyrifos (clo) and a plant compound (citral, menthol or limonene), characterize these nanocarrier systems and verify their performance against larvae and engorged females of R. microplus. Nine formulations were developed and characterized by Dynamic Light Scattering (DLS) and Nanoparticle Tracking Analysis (NTA). The formulations 1 (NLS+cip+clo+citral), 2 (NLS+cip+clo+menthol), 3 (NLS+cip+clo+limonene), 4 (CLN+cip+clo+citral), 5 (CLN+cip+clo+menthol) and 6 (CLN+cip+clo+limonene) obtained mean diameters from 286 to 304 nm; polydispersion from 0.16 to 0.18; zeta potential from -15.8 to -20 mV, concentration from 3.37 ± 0.24 x 1013 to 5.44 ± 0.18 x 1013 particles/mL; and Encapsulation Efficiency (EE) > 98.01% for all active ingredients, while, for the same parameters, zein formulations NZ-1 (NZ+cip+clo+citral), NZ-2 (NZ+cip+clo+menthol) and NZ-3 (NZ+cip+clo+limonene) obtained, respectively, mean values of: 282.18 to 290.64 nm; 0.24 to 0.25; -3.35 to -6.10 mV; concentration of 2.73 ± 2.67 x 1013 to 3.20 ± 3.03 x 1013 particles/mL and EE> 96%. All formulations were evaluated for their acaricidal potential and compared with positive (Colosso®) and negative (distilled water; and nanoparticles without active ingredient) controls. In the evaluation of lipid nanocarrier formulations, by the Larval Pack Test (TPL), the negative controls did not cause mortality of the larvae, while the positive control, evaluated at the concentration of 0.512 mg.mL-1, caused 100% mortality. The formulations of NLS 1, 2, 3 and CLN 4, 5 and 6 were evaluated from 0.004 to 0.466 mg.mL-1. At the concentration of 0.007 mg.mL-1 they reached 90.4, 75.9, 93.8, 100, 95.1, 72.7% of mortality. With the exception of 4, for which it was not possible to determine lethal concentrations (CL), formulations 1, 2, 3, 5 and 6 resulted in CL50 and CL90 of: 0.0033 and 0.0072; 0.0054 and 0.0092; 0.0040 and 0.0081; 0.0023 and 0.0054; 0.0055 and 0.0094 mg.mL-1, respectively. Regarding the zein nanoformulations evaluated by the TPL, the negative controls also did not cause mortality of the larvae, however, the positive control (evaluated from 0.004 to 0.512 mg.mL-1), resulted in larval mortality > 71.9% in the concentration 0.064 mg.mL-1, while zein formulations (evaluated from 0.004 to 0.466 mg.mL-1) caused mortality> 80% in the concentration of 0.029 mg.mL-1. These formulations NZ-1 (NZ + cip + clo + citral), NZ-2 (NZ + cip + clo + menthol) and NZ-3 (NZ + cip + clo + limonene) still resulted in high larval mortality rates in lower concentrations, with LC50 and LC90 of: 0.0136 and 0.0352; 0.0115 and 0.0386; 0.0117 and 0.0301 mg.mL-1, respectively, and 0.0319 and 0.1028 mg.mL-1, respectively, for the positive control). The zein formulations were also evaluated by the Adult Immersionviii Test (TIA) and the formulations NZ-1, NZ-2 and NZ-3 obtained, respectively: 50.2, 40.5 and 60.1% efficacy on engorged females at a concentration of 0.466 mg.mL-1, while the positive control resulted in 39.4% efficacy at 0.512 mg. mL-1. The zein formulations still showed a high residual activity, although less than that of the positive control. This study demonstrated that it was possible to encapsulate the prioritized active ingredients and characterize the carrier systems. All nanoformulations were able to protect the active ingredients against degradation in solution, which is a characteristic of stability aimed at commercial tick products. Thus, nanoformulations can be an alternative for the development of new biocarpathicides with less active ingredients, aiming to promote safer parasitic control, with less risk of the presence of residues in food of animal origin and in the environment.

Avaliação in vitro de carrapaticidas no controle de Rhipicephalus (Boophilus) microplus (Canestrini, 1887), no norte do estado do Rio de Janeiro, Brazil / In vitro analyses of acaricides in control of Rhipicephalus (Boophilus) microplus (Canestrini, 1887), in the northern region of Rio de Janeiro State, Brazil

Background: Rhipicephalus (Boophilus) microplus (Canestrini, 1887) traditionally known as cattle tick, is the species that most affects cattle productivity levels in Brazil. The parasite causes annual losses up to US$ 2 billion. Despite several researches carried out all over the globe, it still presents great challenge, especially due to evidence of resistance to chemical products used in plague control. The goal of this project was to verify in vitro efficiency of pesticides in controlling R. (B.) microplus, at Campos dos Goytacazes municipality, Rio de Janeiro, Brazil, in 2007. Materials, Methods & Results: The in vitro test used was the one recommended by FAO's (Food and Agriculture Organization) World Acaricides Resistance Reference Center (WARRC). Engorged females were manually collected off the ground from stalls and separated in two treatments, amitraz 12.5% (commercial dilution 1:500 = 2 mL/1000 mL) and cypermethrin 15% (commercial dilution 1:1000 = 1 mL/1000 mL), each one with six groups of ten parasites. A different solution - 1:10, 1:100, 1:1000, 1:100000 and 1:1000000 - for both acaricides tested was used on each group, and for control was used potable water. The test was started from the highest dilution. Each dilution was repeated three times simultaneously. Recommended dilutions in the research were in the protocol. Each group of engorged females was weighted in analytical precision scale with equivalence in measurement of weights and, further, transferred to a Becker, containing 50 mL of the solution to be tested, previously prepared. The Becker was kept in constant agitation for five min. Afterwards, the engorged females were put upon towel paper (15 cm²) in order to remove excess of the product, being then transferred to Petri plates (100 mm x 20 mm height), identified and taken to a BOD incubator at 28°C (± 1) and 80% humidity. After oviposition, the number of eggs laid by each group were weighted and inserted in previously adapted plastic syringes, identified and taken again to the same incubator. We conducted the reading of the eggs hatching percentage after 30 days, with a stereoscopic microscope, using as reference the hatching observed in the control group that was kept on a different incubator. The reproduction efficiency (RE) was calculated using the equation; RE = eggs' weight/female's weight x % hatching x 20.000. The control percentage was calculated following the equation, considering the arithmetic mean of three repetitions: % control = RE (non-treated) - RE (treated)/RE non-treated x 100. We obtained as results after a 30 days analysis, a mean percentage of total efficiency of 96.60% for amitraz 12.5% and of 98.00% for cypermethrin 15% in the control of eggs hatching. Discussion: The amitraz 12.5% and the cypermethrin 15% presented excellent results in controlling wild strains of R. (B.) microplus that attacks cattle at Campos dos Goytacazes municipality, Rio de Janeiro, agreeing with FAO's WARRC and the Ministério da Agricultura, Pecuária e Abastecimento (MAPA), which established a legally accepted efficacy for acaricides being equal or superior to 80.00% and 95.00%, respectively, over tick strains. Hence the importance of this pioneer project in the region and its contribution to the subject extension.

In vitro analyses of acaricides in control of Rhipicephalus (Boophilus) microplus (Canestrini, 1887), in the northern region of Rio de Janeiro State, Brazil / Avaliação in vitro de carrapaticidas no controle de Rhipicephalus (Boophilus) microplus (Canestrini, 1887), no norte do estado do Rio de Janeiro, Brazil

Background: Rhipicephalus (Boophilus) microplus (Canestrini, 1887) traditionally known as cattle tick, is the species that most affects cattle productivity levels in Brazil. The parasite causes annual losses up to US$ 2 billion. Despite several researches carried out all over the globe, it still presents great challenge, especially due to evidence of resistance to chemical products used in plague control. The goal of this project was to verify in vitro efficiency of pesticides in controlling R. (B.) microplus, at Campos dos Goytacazes municipality, Rio de Janeiro, Brazil, in 2007.Materials, Methods & Results: The in vitro test used was the one recommended by FAOs (Food and Agriculture Organization) World Acaricides Resistance Reference Center (WARRC). Engorged females were manually collected off the ground from stalls and separated in two treatments, amitraz 12.5% (commercial dilution 1:500 = 2 mL/1000 mL) and cypermethrin 15% (commercial dilution 1:1000 = 1 mL/1000 mL), each one with six groups of ten parasites. A different solution - 1:10, 1:100, 1:1000, 1:100000 and 1:1000000 - for both acaricides tested was used on each group, and for control was used potable water. The test was started from the highest dilution. Each dilution was repeated three times simultaneously. Recommended dilutions in the research were in the protocol. Each group of engorged females was weighted

Background: Rhipicephalus (Boophilus) microplus (Canestrini, 1887) traditionally known as cattle tick, is the species that most affects cattle productivity levels in Brazil. The parasite causes annual losses up to US$ 2 billion. Despite several researches carried out all over the globe, it still presents great challenge, especially due to evidence of resistance to chemical products used in plague control. The goal of this project was to verify in vitro efficiency of pesticides in controlling R. (B.) microplus, at Campos dos Goytacazes municipality, Rio de Janeiro, Brazil, in 2007.Materials, Methods & Results: The in vitro test used was the one recommended by FAOs (Food and Agriculture Organization) World Acaricides Resistance Reference Center (WARRC). Engorged females were manually collected off the ground from stalls and separated in two treatments, amitraz 12.5% (commercial dilution 1:500 = 2 mL/1000 mL) and cypermethrin 15% (commercial dilution 1:1000 = 1 mL/1000 mL), each one with six groups of ten parasites. A different solution - 1:10, 1:100, 1:1000, 1:100000 and 1:1000000 - for both acaricides tested was used on each group, and for control was used potable water. The test was started from the highest dilution. Each dilution was repeated three times simultaneously. Recommended dilutions in the research were in the protocol. Each group of engorged females was weighted

Efficacy of cypermethrin on the control of Struthiolipeurus spp. (Phthiraptera: Philopteridae) in ostrich / Eficácia da cipermetrina no controle de Struthiolipeurus spp. (Phthiraptera: Philopteridae) em avestruz

Duzentos e quarenta avestruzes, com idades entre 12 e 24 meses, foram examinados quanto ao parasitismo por Struthiolipeurus spp. Destes, 168 apresentavam-se infestados por piolhos (70 por cento). Todas as aves foram tratadas com solução de cipermetrina a 15 por cento, na diluição de 1ml/l, por pulverização com auxílio de uma bomba costal. Os animais positivos foram reexaminados nos dias 7, 14 e 21 após o tratamento, e não foram mais encontrados piolhos. A cipermetrina apresentou 100 por cento de eficácia no controle de piolhos do gênero Struthiolipeurus em avestruz.(AU)

Effectiveness of the compound chlorpyrifos+ cypermethrin+citronellal against Alphitobius diaperinus: laboratory analysis and residue determination in carcasses

Effectiveness, biological security and the absence of residues in meat and/or eggs must be considered when recommending options for the control Alphitobius diaperinus in poultry production environments. This research study evaluated the effectiveness of cypermethrin+ chlorpyrifos+citronellal in the control of A. diaperinus, including analysis for the presence of residues of this compound in poultry carcasses (experimental farm). Two studies were carried out under laboratory conditions. One used paper filters a four dilutions of the compound, and the other used a container including with pulverized broiler litter and the compound. The analysis of carcasses for residues was conducted in broilers that raised in a broiler house treated (floor and/or litter) with the compound at a dilution of 1:800. Birds were regularly sacrificed, submitted to necropsy, and liver, muscle and fat fragments were collected. Gas chromatography was used to identify the possible presence of any chemical residue in these samples. High effectiveness rates against A.diaperinus were observed in the two laboratory studies, as well as the absence of residues in the carcasses. This compound, used in the studied concentrations, can be recommended as a valuable alternative for the control and treatment of A. diaperinus.

Effectiveness of the compound chlorpyrifos+ cypermethrin+citronellal against Alphitobius diaperinus: laboratory analysis and residue determination in carcasses

Effectiveness, biological security and the absence of residues in meat and/or eggs must be considered when recommending options for the control Alphitobius diaperinus in poultry production environments. This research study evaluated the effectiveness of cypermethrin+ chlorpyrifos+citronellal in the control of A. diaperinus, including analysis for the presence of residues of this compound in poultry carcasses (experimental farm). Two studies were carried out under laboratory conditions. One used paper filters a four dilutions of the compound, and the other used a container including with pulverized broiler litter and the compound. The analysis of carcasses for residues was conducted in broilers that raised in a broiler house treated (floor and/or litter) with the compound at a dilution of 1:800. Birds were regularly sacrificed, submitted to necropsy, and liver, muscle and fat fragments were collected. Gas chromatography was used to identify the possible presence of any chemical residue in these samples. High effectiveness rates against A.diaperinus were observed in the two laboratory studies, as well as the absence of residues in the carcasses. This compound, used in the studied concentrations, can be recommended as a valuable alternative for the control and treatment of A. diaperinus.

Insecticide susceptibility of horn flies, Haematobia irritans (Diptera: Muscidae), in the State of Mato Grosso do Sul, Brazil

Horn fly susceptibility to insecticides was evaluated in the state of Mato Grosso do Sul, Brazil, from October 2000 to September 2002. Insecticide bioassays (n=57) were conducted in 38 ranches from 14 municipalities throughout the state. Horn flies from wild populations were collected on cattle and exposed to filter papers impregnated with cypermethrin, permethrin, or diazinon and mortality was assessed after two hours. Resistance to cypermethrin was detected in all populations, with resistance ratios (RR) ranging from 27.6 to 91.3-fold. Permethrin bioassays provided apparently low levels of resistance (RR 5), however, resistant flies were found in 96.9% of the populations based on diagnostic concentrations. From both pyrethroid bioassays, resistance was detected in 97.4% of the populations. On the other hand, a high susceptibility to diazinon (RR 1.1) was detected in all populations. Pyrethroid products, most cypermethrin (92.3%) and deltamethrin (66.7%), were used in all ranches controlling horn flies (97.5%). Insecticide treatments, usually incorrectly applied, were routinely delivered by manual backpack sprayers in most ranches (84.5%). This profile of insecticide use helps to explain the widespread resistance of horn flies to pyrethroids in the state as well as their high susceptibility to the organophosphate. Inadequate control practices contribute to aggravate the resistance problem and its consequences.

A suscetibilidade da mosca-dos-chifres a inseticidas foi avaliada no estado de Mato Grosso do Sul de outubro/2000 a setembro/2002 com a realização dos ensaios biológicos (n=57) em 38 propriedades, de 14 municípios. Moscas coletadas em bovinos foram expostas a papéis de filtro impregnados com cipermetrina, permetrina, ou diazinon, registrando-se a mortalidade após duas horas. Resistência à cipermetrina foi detectada em todas as populações, com fatores de resistência (FR) entre 27,6 e 91,3. Ensaios biológicos com permetrina resultaram em níveis de resistência aparentemente baixos (FR 5), entretanto, o uso de concentrações diagnósticas evidenciaram a ocorrência de moscas resistentes em 96,9% das populações. Considerando ambos os bioensaios com piretróides, 97,4% das populações apresentaram resistência. De outro modo, todas as populações demonstraram elevada suscetibilidade ao diazinon (FR 1.1). Todas as propriedades onde o controle da mosca-dos-chifres era realizado (97,5%) utilizavam produtos piretróides, principalmente à base de cipermetrina (92,3%) e deltametrina (66,7%). Tratamentos inseticidas utilizando bombas costais manuais eram realizados em 84,5% das propriedades, geralmente de forma inadequada. O perfil de uso de inseticidas nas propriedades contribui para explicar a ampla ocorrência de resistência da mosca-dos-chifres aos piretróides, assim como a elevada suscetibilidade aos organofosforados, no Estado. Práticas inadequadas de controle contribuem para agravar o problema da resistência e suas conseqüências.

Ensaio do "Cypermethrin" a 25%, aplicado sobre a pele do dorso, no tratamento de cães naturalmente infestados com pulgas e carrapatos

Nova técnica, com equipamento especial, construído de gaiolas metálicas revestidas de pano de algodão, à prova de entrada e saída de ectoparasitos, é introduzida para teste de drogas contra os mesmos. Com algumas correções de falhas do primeiro delineamento experimental utilizado, tal técnica revelou-se de real vantagem no estudo da atividade de "Cypermethrin", em solução a 25%, aplicada na pele de cães, contra pulgas e carrapatos. A droga foi 100% ativa como pulicífuga ou pulicida e mostrou considerável atividade carrapatífuga e carrapatostática.

Ensaio do "Cypermethrin" a 25%, aplicado sobre a pele do dorso, no tratamento de cães naturalmente infestados com pulgas e carrapatos

Nova técnica, com equipamento especial, construído de gaiolas metálicas revestidas de pano de algodão, à prova de entrada e saída de ectoparasitos, é introduzida para teste de drogas contra os mesmos. Com algumas correções de falhas do primeiro delineamento experimental utilizado, tal técnica revelou-se de real vantagem no estudo da atividade de "Cypermethrin", em solução a 25%, aplicada na pele de cães, contra pulgas e carrapatos. A droga foi 100% ativa como pulicífuga ou pulicida e mostrou considerável atividade carrapatífuga e carrapatostática.  

Distribution, host range and toxicity assessment of different insecticides on Bactrocera diversa Coquillett, 1904 (Diptera: Tephritidae) / Avaliação da distribuição, gama de hospedeiros e toxicidade de diferentes inseticidas em Bactrocera diversa Coquillett, 1904 (Diptera: Tephritidae)

Abstract The present study was conducted to investigate the array of hosts, distribution and to evaluate the toxicity of four insecticides: imidacloprid, fipronil, cypermethrin and chlorpyrifos alone and in combination against 3rd instar maggot and adult stage of fruit fly Bactrocera diversa Coquillett, 1904 (Diptera: Tephritidae) during 2021. B. diversa maggots were found vigorously feeding inside the cucurbit hosts (pumpkin, cucumber, bitter gourd, watermelon, round melon, bottle gourd) collected from different localities of Poonch division of Azad Jammu and Kashmir, Pakistan, and this species is reported for the first time as new record to this region. Susceptibilities of B. diversa to insecticides were evaluated using topical method. Mortality was checked after 3, 6, 8 and 24h of exposure. Cypermethrin was most effective to kill 50% of both larval and adult stage with least LC50 [7.2(1.040±0.214), 17.4(0.748±0.193)], respectively followed by imidacloprid. Imidacloprid most effectively killed 90% of both larval and adult population with least LC90 value [73.2 (3.013±0.708) 16.9 (1.886±0.437)] respectively after 24 hours. Cypermethrin with chlorpyrifos most effectively killed 50 and 90 percent of both larval and adult stage of B. diversa with least LC50 value [11.3 (1.085±0.245), 2.5 (0.759±0.252)] and least LC90 value [171.3 (1.085±0.245), 121.9 (0.759±0.252)], respectively after 24h of exposure. Toxicity of each insecticide increased with exposure for longer time and increased dose. Cypermethrin is suggested as most effective against both larval and adult stages of B. diversa in combination with chlorpyrifos followed by imidacloprid.

O presente estudo foi conduzido para investigar a variedade de hospedeiros, distribuição e avaliar a toxicidade de quatro inseticidas: imidaclopride, fipronil, cipermetrina e clorpirifós isoladamente e em combinação contra larva de 3º ínstar e estágio adulto da mosca-das-frutas Bactrocera diversa Coquillett, 1904 (Diptera: Tephritidae) durante 2021. Larvas de B. diversa foram encontradas se alimentando vigorosamente dentro dos hospedeiros de cucurbitáceas (abóbora, pepino, cabaça amarga, melancia, melão redondo, cabaça) coletados em diferentes localidades da divisão Poonch de Azad Jammu e Caxemira, Paquistão, e essa espécie é relatada pela primeira vez como novo registro para essa região. A suscetibilidade de B. diversa a inseticidas foi avaliada por método tópico. A mortalidade foi verificada após 3, 6, 8 e 24 horas de exposição. A cipermetrina foi mais eficaz para matar 50% do estágio larval e adulto com menos CL50 [7,2(1,040 ± 0,214), 17,4 (0,748±0,193)], respectivamente, seguido por imidaclopride. O imidaclopride matou mais efetivamente 90% da população larval e adulta com o menor valor de LC90 [73,2 (3,013 ± 0,708) 16,9 (1,886 ± 0,437)], respectivamente, após 24 horas. Cipermetrina com clorpirifós matou mais efetivamente 50% e 90% do estágio larval e adulto de B. diversa com valor mínimo de LC50 [11,3 (1,085 ± 0,245), 2,5 (0,759 ± 0,252)] e valor mínimo de LC90 [171,3 (1,085 ± 0,245), 121,9 (0,759 ± 0,252)], respectivamente, após 24 horas de exposição. A toxicidade de cada inseticida aumentou com a exposição por mais tempo e com o aumento da dose. A cipermetrina é sugerida como mais eficaz contra os estágios larval e adulto de B. diversa em combinação com clorpirifós seguido de imidaclopride.