Potential predation and fecundity of Amblyseius aerialis fed two-spotted spider mite

The mites of the Phytoseiidae family stand out for the biological control of pest mites. The species Amblyseius aerialis (Muma, 1955) is a generalist mite, which can contribute to the natural regulation of pest mites. The objective of this study was to evaluate the potential for predation and fecundity of A. aerialis on the different phases of Tetranychus urticae (Koch, 1836) (Acari: Tetranychidae). A female of A. aerialis was confined on dish (3.0 cm in diameter) of jack bean leaves, Canavalia ensiformis (L.) DC. The discs were left in petri dish with water. Each T. urticae phase was offered individually to A. aerialis at densities: 2, 5, 10, 15, 20 and 30 mites / arena. The number of prey consumed and eggs laid by A. aerialis were evaluated every 24 hours for seven days, with removal of laid eggs by phytoseiid and dead prey and replacement of prey in the initial amount. The data were submitted to analysis of variance and the means were compared by Tukey test, applying the factorial (4x6). It was observed that with the increase of the density of T. urticae offered there was an increase in the predation of A. aerialis. When offered the nymph and adult the average number of eggs per day was higher, differing from egg and larva. Thus, A. aerialis can be a biological control agent of the T. urticae, reducing the population of the pest and maintaining its fecundity in all phases and densities offered.The mites of the Phytoseiidae family stand out for the biological control of pest mites. The species Amblyseius aerialis (Muma, 1955) is a generalist mite, which can contribute to the natural regulation of pest mites. The objective of this study was to evaluate the potential for predation and fecundity of A. aerialis on the different phases of Tetranychus urticae (Koch, 1836) (Acari: Tetranychidae). A female of A. aerialis was confined on dish (3.0 cm in diameter) of jack bean leaves, Canavalia ensiformis (L.) DC. The discs were left in petri dish with water. Each T. urticae phase was offered individually to A. aerialis at densities: 2, 5, 10, 15, 20 and 30 mites / arena. The number of prey consumed and eggs laid by A. aerialis were evaluated every 24 hours for seven days, with removal of laid eggs by phytoseiid and dead prey and replacement of prey in the initial amount. The data were submitted to analysis of variance and the means were compared by Tukey test, applying the factorial (4x6). It was observed that with the increase of the density of T. urticae offered there was an increase in the predation of A. aerialis. When offered the nymph and adult the average number of eggs per day was higher, differing from egg and larva. Thus, A. aerialis can be a biological control agent of the T. urticae, reducing the population of the pest and maintaining its fecundity in all phases and densities offered

Patogenicidad y multiplicación de aislados de nemátodos entomopatógenos para el control de Plutella xylostella (Linnaeus) (Lepidoptera: Plutellidae)

La relevancia de las hortalizas en el sector económico es reconocida por su importancia social, generando empleos e ingresos en la agricultura familiar. El cultivo de brasicáceas o crucíferas es uno de los más demandados en el mundo, siendo la palomilla Plutella xylostella (Linnaeus) su principal plaga, debido a su fácil dispersión, corto ciclo de vida y gran capacidad de desarrollar resistencia a los insecticidas. Por tal motivo, la adopción de métodos de control alternativo son importantes para la elaboración de un plan de manejo integrado de plagas, orientado a una producción sustentable. Por lo cual, es necesario que sean desarrolladas técnicas seguras de control de plagas responsables de efectos limitantes en la producción hortícola. Otra estrategia potencial en el control de plagas, mediante el control microbiano, son los nemátodos entomopatógenos, que no dejan residuos químicos en los cultivos y no contaminan el medio ambiente. Así, el objetivo de este trabajo fue evaluar la patogenicidad y multiplicación de aislados de nemátodos entomopatógenos para el control de P. xylostella. Utilizando técnicas de inoculación, fueron realizados dos experimentos en el tercer y cuarto instar de la plaga. Los nemátodos presentaron un ciclo de vida corto y alta capacidad de virulencia sobre la plaga, representando una alternativa eficiente para el control microbiano de la palomilla

BIOATIVIDADE DE PÓS–VEGETAIS NO CONTROLE DE Sitophilus zeamais (MOTSCHULSKY, 1855) (COLEOPTERA: CURCULIONIDAE)

O milho, Zea mays L. é uma gramínea pertencente à família Poaceae que apresenta grande importância para a agricultura mundial. No Brasil, é explorado na maioria das propriedades agrícolas, sendo matéria-prima destinada à agroindústria para a fabricação de farinha, óleo, amido e também para ração animal e também usado como alimento básico de alguns países. Entretanto, problemas relacionados com as pragas que atacam grãos armazenados têm preocupado os produtores que precisam estocar sua produção. Considerada uma das principais pragas, o gorgulho-do-milho (Sitophilus zeamais) (Coleoptera: Curculionidae) é uma praga primária que pode comprometer as sementes tanto em campo como nos armazéns, afetando a qualidade física e fisiológica. Devido a esses problemas, um experimento em laboratório foi realizado com o objetivo de avaliar a bioatividade dos pós-vegetais das espécies Mastruz (Chenopodium ambrosioides L.) (folha), Inhame (Dioscorea sp.) (ramos e folhas) e Mandioca (Manihot esculenta) (casca) no controle de S. zeamais. Foram avaliados a eficiência dos pós-vegetais na mortalidade da praga em teste sem chance de escolha e a repelência dos insetos em teste com chance de escolha. Para o teste sem chance de escolha foram utilizadas as concentrações 0,25; 0,50; 0,75 e 1,0 g dos pós que foram adicionados em recipientes plásticos contendo 10 g de grãos de milho, colocando 20 adultos emergidos com 24 horas. O experimento foi conduzido em delineamento inteiramente casualizado com 10 repetições para cada concentração. Para o teste com chance de escolha foram confeccionadas arenas com cinco recipientes plásticos interligadas por canudos de plástico transparente. Em quatro recipientes foram colocados 10 g de grão de milho, sendo em duas delas adicionado 1g do pó das diferentes espécies vegetais. Posteriormente, foram colocados 20 adultos com idade até 10 dias, no recipiente central. O experimento foi conduzido em delineamento inteiramente casualizado com quatro Revista Mirante, Anápolis (GO), v. 11, n. 7, jun. 2018. ISSN 1981-4089 267 tratamentos e 10 repetições. O pó da espécie vegetal mastruz provocou a mortalidade dos adultos a 1% em testes sem chance de escolha. Em teste com chance de escolha, os pós-vegetais das espécies Inhame e Mastruz apresentaram atividade repelente sobre os adultos de S. zeamais com 28% e 24%, respectivamente

FIRST RECORD OF Xanthopastis timais IN AMARYLLIS AND EFFECT OF SOURSOP EXTRACT ON LARVAL MORTALITY

The aim of this study was to report the occurrence of Xanthopastis timais (Cramer, 1780) (Lepidoptera: Noctuidae) in amaryllis ( Hippeastrum hybridum Hort ., Amaryllidaceae), as well as estimating lethal concentrations (LC 50 and LC 99 ) of soursop seed extract, Annona muricata L. (Annonaceae), against its larvae. The experiment was carried out at the Laboratory of Entomology of the Research Center for Agricultural Sciences, Federal University of Alagoas, in Rio Largo - AL, Brazil . First, we collected caterpillars from amaryllis plants that were reared until pupal and adult stages (parental generation). Next, part of the adults was used for species identification, and the rest were bred to produce next generation (F1), being after that applied in a laboratory bioassay. The lab trial was performed in a completely randomized design, with six treatments and five replications containing three second - instar caterpillars. These larvae were fed pieces of amaryllis leaf (4 x 4 cm), which were previously soaked in treatments for 30 seconds and, air - dried on absorbent papers for one hour. Each treatment consisted of one concentration of ethanol extract of soursop seeds (0.0, 1.0, 0.5, 0.25, 0.125 and 0.0625% w/ v) with distilled water and DMSO at 1% (v/ v), for solutions. We noted that the lethal concentrations LC 50 and LC 99 were 0.29% (w/ v) and 2.27% (w/ v), respectively. In view of our results, we can state that larval stage of X . timais were influenced by extract application in terms of survival, mortality, larvae weight and larval stage length. Besides of that, it was the first time this species was recorded in Alagoas state

Bioactivity of microencapsulated soursop seeds extract on Plutella xylostella

ABSTRACT: The aim of this study was to evaluate the bioactivity of microencapsulated extract from the soursop seeds, Annona muricata L. ( Annonaceae ), on diamondback moth, Plutella xylostela L. (Lepidoptera: Plutellidae ). Microencapsulation was performed in a Mini Spray Dryer model B-290 using 50mL of ethanolic and hexanic extracts plus 150mL of ethanol and 150mL of ultrapure water, mixed with aerosil (first polymer) or arabic gum (second polymer). It was possible to microencapsulate the ethanolic extract of soursop seeds only by using the polymer arabic gum at 20%. The microencapsulated extract caused significant acute toxicity (LC50=258mg L-1) and chronic effects, especially reduction of larval viability and increased larval stage. We concluded that the microencapsulation of the ethanolic extract of soursop seeds can be a viable alternative for controlling diamondback moth with possible gains for the environment

Ação De Extratos Vegetais Sobre Trichogramma galloi (Zucchi, 1988) (Hymenoptera: Trichogrammatidae)

The plants extract may be compatible with other management tactics, especially with biologicalcontrol. so the aim of this work was to evaluate the residual effect of several extracts from cedartree (C) and mahogany tree (M) (bark (C), wood (M) and leaf (F); cecropia tree (I) (bark - C andwood - M) and of the pereiro (P) (bark -C), and its possible effects on the adults of the parasitoidTrichogramma galloi(Zucchi, 1988) (Hymenoptera: Trichogrammatidae). Cards containingparasitised eggs of Diatraea saccharalis(Fabricius, 1794) (Lepidoptera: Crambidae), or containigeggs that would be submitted to the parasitoid were immersed for 30 seconds in the extracts at 5000μg.mL-1. The number of parasitised eggs and adult emergence of the parasitoid were evaluated.The highest rates of parasitism, up to 60.0%, was obtained by the control treatment, MC, MM, CCand MF, and the treatments that caused a lower percentage of parasitism, IC, IM, PC, CM andCF, respectively. The extracts of different parts of mahogany, which showed a good percentageof parasitism, affected the development of the parasitoid with a low adult emergence. The PCshowed a lower parasitism and emergence. In relation to eggs treated four days after parasitism,it was found that the control treatment had a good average in emergency (98.85%), in the samecategory of treatments IM, CF and CC, respectively. The CC extract was more selective and the PCwas the least selective for T. galloi.Os extratos vegetais podem ser compatíveis com outras táticas de manejo, principalmente com o controle biológico. Desta forma, objetivou-se neste trabalho avaliar o efeito residual dos extratos de Cedrela fissilis Vell. (Meliaceae) cedro (C) e Swietnia macrophylla King Vell. (Meliaceae) mogno (M) (casca- C), madeira (M) e folha (F); Cecropia pachystachya (Cecropiaceae) imbaúba (I) (casca - C e madeira - M) e Aspidosperma pyrifolium Mart. (Apocynaceae) pereiro (P) (casca - C), sobre adultos do parasitoide Trichogramma galloi (Zucchi, 1988) (Hymenoptera: Trichogrammatidae). Cartelas contendo ovos de Diatraea saccharalis (Fabricius, 1794) (Lepidoptera: Crambidae) parasitados, ou que seriam submetidos aos parasitoides, foram imersas por 30 segundos nos extratos a 5000 mg.mL-1. Avaliaram-se o número de ovos parasitados e a emergência dos adultos do parasitoide. As maiores taxas de parasitismo, acima de 60,0 %, foram obtidas pela testemunha, MC e MM, CC e MF; e os tratamentos que causaram menor percentagem de parasitismo foram IC, IM, PC, CM e CF, respectivamente. Os extratos das diferentes partes do mogno, que apresentaram uma boa percentagem de parasitismo, afetaram o desenvolvimento do parasitoide, com uma baixa emergência de adultos. O PC apresentou um valor baixo de parasitismo e de emergência. Em relação aos ovos tratados quatro dias após o parasitismo, verificou-se que a testemunha apresentou uma boa emergência (98,85%), semelhantes a IM, CF e CC, , respectivamente. O CC foi o extrato mais seletivo e o PC foi o menos seletivo para T. galloi. Action of plants extract on Trichogrammagalloi (Zucchi, 1988)(Hymenoptera: Trichogrammatidae)AbstractThe plants extract may be compatible with other management tactics, especially with biologicalcontrol. so the aim of this work was to evaluate the residual effect of several extracts from cedartree (C) and mahogany tree (M) (bark (C), wood (M) and leaf (F); cecropia tree (I) (bark - C andwood - M) and of the pereiro (P) (bark -C), and its possible effects on the adults of the parasitoidTrichogramma galloi(Zucchi, 1988) (Hymenoptera: Trichogrammatidae). Cards containingparasitised eggs of Diatraea saccharalis(Fabricius, 1794) (Lepidoptera: Crambidae), or containigeggs that would be submitted to the parasitoid were immersed for 30 seconds in the extracts at 5000μg.mL-1. The number of parasitised eggs and adult emergence of the parasitoid were evaluated.The highest rates of parasitism, up to 60.0%, was obtained by the control treatment, MC, MM, CCand MF, and the treatments that caused a lower percentage of parasitism, IC, IM, PC, CM andCF, respectively. The extracts of different parts of mahogany, which showed a good percentageof parasitism, affected the development of the parasitoid with a low adult emergence. The PCshowed a lower parasitism and emergence. In relation to eggs treated four days after parasitism,it was found that the control treatment had a good average in emergency (98.85%), in the samecategory of treatments IM, CF and CC, respectively. The CC extract was more selective and the PCwas the least selective for T. galloi