RESUMO

Phytoseiidae is a large family of Mesostigmata mites. Members of this family are important biological control agents across the world since they are well-known natural enemies of phytophagous arthropods on cultivated and non-cultivated plants, mainly used to control pest spider mites. However, some can control thrips in greenhouses and fields. Several studies reporting on species in Latin America have been published. The most extensive studies were conducted in Brazil. Phytoseiid mites have been used in different biological control approaches, with two successful classical biological control programs: the biocontrol of the cassava green mite using Typhlodromalus aripo (Deleon) in Africa and the citrus and avocado mites by Euseius stipulatus (Athias-Henriot) in California. Efforts in using phytoseiid mites to enforce biological control of different phytophagous mites are being made in Latin America. Till now, only a few successful examples are available on this topic. This fact highlights the need to continue the investigations on the ability of other unknown species to be used in biological control through close collaboration between researchers and biocontrol companies. Various challenges remain, such as developing better rearing systems to provide a large number of predators to farmers in various crop systems, training farmers to improve their understanding of the use of predators, and chemical control aimed at conservation biological control, looking forward to increasing the use of the phytoseiid mites as biological control agents in Latin America and the Caribbean.

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The Amazon is an important source of natural enemies for biological control. The diversity of biocontrol agents in the Amazon is considerably higher than that in other Brazilian regions. However, few studies have focused on the bioprospecting of natural enemies in the Amazon. Furthermore, the expansion of agricultural land in recent decades has caused biodiversity loss in the region, including the loss of potential biocontrol agents, due to the replacement of native forests with cultivated areas and forest degradation. In this study, we reviewed the main groups of natural enemies in the Brazilian Legal Amazon: predatory mites (mainly Acari: Phytoseiidae), ladybirds (Coleoptera: Coccinellidae), and social wasps (Hymenoptera: Vespidae: Polistinae) and the Hymenoptera parasitoids of eggs (Trichogrammatidae) and of frugivorous larvae (Braconidae and Figitidae). The main species prospected and used in biological control are presented. The lack of knowledge and perspectives regarding these groups of natural enemies as well as the challenges of conducting research in the Amazon is discussed.

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Lychee fruit production (Litchi chinensis) has been threatened in many regions of the world where the presence has been reported of the litchii erinose mite, Aceria litchii (Keifer). This study aims to identify the arthropod community associated with A. litchii on lychee plants in Minas Gerais, Brazil, and to seek for potential natural enemies associated with this mite pest in this region. We sampled lychee leaves infested with A. litchii in commercial and non-commercial lychee orchards during seven consecutive months, covering the dry and wet seasons of the year. Arthropods found in association with A. litchii on lychee leaves were collected and identified. The results indicate that a great diversity and abundance of mites and hexapods are associated with A. litchii. A total of 985 and 1872 specimens of mites were identified in commercial and non-commercial areas, respectively, belonging to the families Cheyletidae, Cunaxidae, Eupodidae, Iolinidae, Stigmaeidae, Phytoseiidae, Tarsonemidae, Tenuipalpidae, Tetranychidae, Tryophtydeidae, Tuckerellidae, Tydeidae, Winterschmidtiidae and Xenocaligonellidae and the suborder Oribatida. Among them, Phytoseiidae was the most abundant and diverse family with a total of 11 species identified, in which Phytoseius intermedius was the most abundant predatory mite species collected. Minor specimens of hexapods were also been, belonging to the orders Collembola, Blattodea, Coleoptera, Diptera, Hemiptera, Hymenoptera, Psocoptera and Thysanoptera. The presence of a high community of predatory mites in association with A. litchii deserves attention and our results indicate that studies to test the potential of these species and the adoption of management practices that enhance this ecological service must be carried out to achieve satisfactory control of the lychee erinose mite in lychee plants.

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The aim of this study was to identify mite fauna associated with soybean crops and to report new species of the Monsoy 8349 IPRO variety in the municipality of Luís Eduardo Magalhães, western region of Bahia. Samplings were performed in an area with transgenic soybeans, subdivided into three treatments: T01, with no use of agricultural pesticides; T02, complete package of pesticides, except for acaricides; and T03, complete package of pesticides including acaricides. Twenty plants were selected per treatment at each sampling; one apical, one median, and one basal leaf were collected from each plant, totaling 60 leaves per treatment. A total of 1,292 mites were found, belonging to three families, five genera, and six species. The major phytophagous mite species found were Mononychellus planki McGregor and Tetranychus urticae Koch, while the major predatory mites found were Neoseiulus transversus Denmark & Muma and Euseius concordis Chant.

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Several phytoseiid mite species are important natural enemies used in biological control strategies. In the present study, Cytb mtDNA sequences of various populations of two species, Phytoseiulus macropolis and P. persimilis, were compared to determine whether the specimens collected in Brazil could belong to P. persimilis as this latter species is reported in South America but not in Brazil. The Cytb marker was used because of its high evolution rate, assumed to capture intraspecific variation. No overlap between intra- and interspecific distances was observed but the distances were quite low for interspecific variation. This can be due to the particular biology of Phytoseiulus species and this shows the difficulty to apply a universal threshold in genetic distances to conclude about the existence of one or several species. Cytb mtDNA sequences were also considered to assess intraspecific variation. The DNA sequences of P. persimilis populations were very similar, probably because they all originated from the West Palearctic region or because of a prevalence of commercialized specimens in natura. For P. macropilis, higher genetic distances were observed and differentiation was noted according to geographic location and, to a smaller extent, pyrethroid resistance. To determine how DNA variation might impact the protein function (CytB fragment considered), the amino acid compositions of the populations studied were compared. No diagnostic mutation was observed between pyrethroid resistant and susceptible populations, whereas four mutations were identified between populations of P. macropilis separated by 1300 km (different climatic conditions). The impact of such mutations is discussed but knowledge is scarce, which makes it difficult to root testable hypotheses. The protein analysis clearly opens new perspectives in Phytoseiidae studies.

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Because predators may interfere with each other, an important step towards the implementation of successful release of multiple predators in biocontrol programs requires resolving how predators respond to the presence of heterospecific competitors. Several species of predatory mites are important biocontrol agents and the species Phytoseiulus macropilis and Neoseiulus californicus are used to control the two-spotted spider mite, Tetranychus urticae, an important pest in agriculture worldwide. We investigated their compatibility showing that the two predators do not avoid plants on which the other species is present together with their common prey, and demonstrated that their oviposition rates are not affected by the presence of the other species. However, the distribution of the eggs on leaf discs was affected by the presence of the heterospecific predator. This behaviour might weaken possible interference between these two biocontrol agents, which, in turn, may enable their persistence on plants and favour pest suppression. The increased joint use of several natural enemies for biological control highlights the importance of studies on predator-predator interactions.

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Ricoseius loxocheles (De Leon) (Acari: Phytoseiidae) is often found in coffee crops and is known to feed on coffee leaf rust, Hemileia vastatrix Berkeley and Broome (Uredinales). As the occurrence of coffee leaf rust is limited primarily to the rainy season, the mite may use other food sources to survive during the periods of low pathogen prevalence. It is well known that phytoseiid mites can survive on a variety of food sources, such as herbivorous mites, fungi and pollen. We evaluated the ability of R. loxocheles to survive and reproduce on a diet of Brevipalpus phoenicis Geijskes (Acari: Tenuipalpidae), cattail pollen (Typha spp.), clover rust (Puccinia oxalidis), bee pollen (Santa Bárbara® dehydrated pollen, Santa Bárbara, MG, Brazil) and coffee leaf rust. Ricoseius loxocheles did not survive or reproduce on any B. phoenicis stages tested (egg, larva, adult). The survival and oviposition of R. loxocheles were directly affected by the presence of coffee rust urediniospores, but not by the presence of the prey. Survival and oviposition of the phytoseiid were similar when fed cattail pollen, clover rust and coffee leaf rust but was lower when fed bee pollen. Our results show that R. loxocheles is not a predator of B. phoenicis but it is able to utilize other resources besides coffee leaf rust.

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Phytoseiid mites are commonly used as biological control agents of mite and small insect pests. To facilitate the production of phytoseiids, alternative food sources have been evaluated. The aim of this study was to evaluate the suitability of different food sources for the rearing of the phytoseiids Amblyseius tamatavensis Blommers, Euseius concordis (Chant) and Neoseiulus anonymus (Chant and Baker). This study evaluated the levels of oviposition of these predators when fed with 15 Astigmatina (Sarcoptiformes) mite species, one species of a bacteriophagous nematode, and pollen from five plant species. The highest oviposition rates of A. tamatavensis were obtained when fed on the mites Thyreophagus cracentiseta Barbosa, OConnor & Moraes and Aleuroglyphus ovatus (Troupeau) (2.6 and 2.1 eggs/female/day, respectively). The five highest oviposition levels of E. concordis occurred when the food source was pollen, especially of Ricinus communis L. (1.7 eggs/female/day). The evaluated oviposition levels of N. anonymus were at most 0.5 eggs/female/day on all food sources. The construction of life tables of A. tamatavensis and E. concordis with the two most favorable food sources showed that in both cases the values of rm were higher when the predator was fed with T. cracentiseta and R. communis, respectively. The possible use of pollen of Elaeis guineensis L. should be further evaluated, given the acceptance of this type of pollen by E. concordis and the ease of obtaining large amounts of this pollen in areas where this crop is grown.

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The coconut production system, in which the coconut mite Aceria guerreronis is considered a key pest, provides an interesting model for integration of biological and chemical control. In Brazil, the most promising biological control agent for the coconut mite is the phytoseiid predator Neoseiulus baraki. However, acaricides are widely used to control the coconut mite, although they frequently produce unsatisfactory results. In this study, we evaluated the simultaneous direct effect of dry residue contact and contaminated prey ingestion of the main acaricides used on coconut palms (i.e., abamectin, azadirachtin and fenpyroximate) on life-history traits of N. baraki and their offspring. These acaricides are registered, recommended and widely used against A. guerreronis in Brazil, and they were tested at their label rates. The offspring of the exposed predators was also evaluated by estimating the instantaneous rate of population increase (r i ). Abamectin compromised female performance, whereas fenpyroximate did not affect the exposed females (F0). Nonetheless, fenpyroximate strongly compromised the offspring (F1) net reproductive rate (R0), intrinsic rate of population growth (r i ), and doubling time (DT). In contrast, fenpyroximate did not have such effects on the 2nd generation (F2) of predators with acaricide-exposed grandparents. Azadirachtin did not affect the predators, suggesting that this acaricide can be used in association with biological control by this predatory species. In contrast, the use of abamectin and fenpyroximate is likely to lead to adverse consequences in the biological control of A. guerreronis using N. baraki.

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Amblyseius largoensis (Muma) (Acari: Phytoseiidae) and Euseius alatus De Leon (Acari: Phytoseiidae) are predatory mites that are mostly found on leaves and on the exposed fruit surface of coconut plants. Their morphology hampers the access to the microhabitat occupied by Aceria guerreronis Keifer (Acari: Eriophyidae), the most important pest of coconut fruits throughout the world. However, it was suggested that they can prey on A. guerreronis under natural conditions when this pest leaves its refuge to disperse. Since the trophic interactions between A. largoensis or E. alatus and A. guerreronis are unknown, we compare the frequencies of occurrence of A. largoensis and E. alatus under the bracts of coconut fruits and on coconut leaflets. In addition, because phytoseiids feed by liquid ingestion, we used molecular analysis to confirm the potential role of A. largoensis or E. alatus as predators of A. guerreronis and to assess how fast the A. guerreronis DNA fragment is degradated in the A. largoensis digestive tract. Our study demonstrated that E. alatus was only present on coconut leaflets whereas A. largoensis was found mostly on leaflets and, to a much lesser extent, under the bracts of coconuts. Species-specific ITS primers designed for A. guerreronis were shown to have a high degree of specificity for A. guerreronis DNA and did not produce any PCR product from DNA templates of the other insects and mites associated with the coconut agroecosystem. Based on molecular analysis, we confirmed that the predatory mites, A. largoensis and E. alatus, had preyed on the coconut mite in the field. Overall the predatory mites collected in the field exhibited low levels of predation (26.7% of A. largoensis and 8.9% of E. alatus tested positive for A. guerreronis DNA). The fragment of A. guerreronis DNA remained intact for a very short time (no more than 6 h after feeding) in the digestive tract of A. largoensis.

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The purpose of this study was to elaborate a preliminary list of the mite species associated with rubber trees in the municipality of Santana, in the state of Amapá, Brazil. Two collections of rubber tree leaves were conducted on May 2nd and June 5th , 2010. Twenty-five plants were sampled at random. Three leaves were collected per plant, from the lower third of the crown. The samples were placed in paper bags, packed in an isothermal box chilled gel-based pulp plant (Gelo-X®), and transported to the Entomology Laboratory at Embrapa Amapá, in Macapá. The leaflets were examined under a stereomicroscope, and the mites found on the adaxial and abaxial surfaces of the leaves were collected with a stilet, mounted on microscope slides in Hoyer's medium, and later identified. We collected a total of 1,722 mites of 10 families: Acaridae, Cunaxidae, Eriophyidae, Iolinidae, Phytoseiidae, Stigmaeidae, Tarsonemidae, Tenuipalpidae, Tydeidae, and Winterschmidtiidae, in addition to unidentified species of the suborders Oribatida and Astigmatina. The family Phytoseiidae represented only 2.90% of specimens collected, but showed the highest species richness (5 species). The only representative of Tenuipalpidae was Tenuipalpus heveae Baker, 1945, but 81.13% of the mites collected in this study belonged to this species.

O objetivo deste estudo foi elaborar uma lista preliminar das espécies de ácaros associadas à seringueira, no município de Santana, Estado do Amapá. Foram realizadas duas coletas de folhas de seringueira, nos dias 2 de maio e 5 de junho de 2010. Foram tomadas aleatoriamente 25 plantas, de cada uma das quais foram coletadas três folhas, no terço inferior da copa. As amostras foram acondicionadas em sacos de papel, mantidas em caixa isotérmica refrigerada com gel à base de celulose vegetal (Gelo-X®) e transportadas até o Laboratório de Entomologia da Embrapa Amapá, em Macapá. A triagem dos folíolos foi realizada com o auxílio de estereomicroscópio. Os ácaros encontrados nas faces adaxial e abaxial das folhas foram capturados com um estilete, montados em lâminas de microscopia em meio de Hoyer e, posteriormente, identificados. Foram coletados 1.722 ácaros, pertencentes a dez famílias: Acaridae, Cunaxidae, Eriophyidae, Iolinidae, Phytoseiidae, Stigmaeidae, Tarsonemidae, Tenuipalpidae, Tydeidae e Winterschmidtiidae, além de espécies não identificadas das subordens Oribatida e Astigmatina. A família Phytoseiidae representou apenas 2,90% do total de espécimes coletados, porém apresentou a maior riqueza em espécies (cinco espécies). A família Tenuipalpidae, embora representada apenas por Tenuipalpus heveae Baker, 1945, apresentou o maior número de espécimes capturados (81,13%).

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O ácaro-hindustânico-dos-citros, Schizotetranychus hindustanicus (Hirst), é uma praga de importância quarentenária, recentemente introduzida no Brasil. Até a condução do presente estudo, não havia informações na literatura sobre a eficiência de acaricidas no controle de S. hindustanicus, em condições de campo. O estudo teve por objetivo avaliar o efeito de alguns acaricidas, utilizados em pomares de citros no país, sobre o ácaro-praga e ácaros predadores (Phytoseiidae) presentes na cultura. O experimento foi conduzido em um pomar de citros (limão-tahiti), em Boa Vista, RR. Os acaricidas testados e respectivas concentrações (g i.a./100 L de água) foram: mancozebe (200), abamectina (0,36), espirodiclofeno (6), enxofre (400) e dimetoato (80). A aplicação foi realizada com equipamento acoplado a um trator, provido de pistolas, aplicando-se 10 litros de calda por planta. O delineamento estatístico foi inteiramente casualizado com seis tratamentos e cinco repetições. As avaliações foram realizadas aos 1, 4, 7, 14, 28, 42 e 56 dias após a aplicação (DAA). Em cada avaliação, foram coletados 20 folhas e 10 frutos por parcela, contando-se o número de ácaros S. hindustanicus e fitoseídeos. Todos os produtos reduziram significativamente a população do ácaro-hindustânico nas folhas até 28 DAA. Os acaricidas dimetoato e espirodiclofeno foram altamente eficientes no controle de S. hindustanicus, sendo que o espirodiclofeno apresentou um período de controle mais longo que dimetoato. Com relação aos ácaros predadores, dimetoato, enxofre e abamectina causaram mortalidades significativas (72 a 100%) aos fitoseídeos, até 4 DAA. A espécie predominante de fitoseídeo foi Euseius concordis (Chant), correspondendo a 71% dos ácaros observados. (AU)

EFFECT OF ACARICIDES ON SCHIZOTETRANYCHUS HINDUSTANICUS (HIRST) (ACARI: TETRANYCHIDAE) AND PREDACEOUS MITES ON CITRUS IN THE STATE OF RORAIMA, BRAZIL. Schizotetranychus hindustanicus (Hirst) is a pest of quarantine importance, recently introduced in Brazil. There was no information in the literature, on the efficacy of acaricides for the control of S. hindustanicus (Hirst) under field conditions, up to the conduction of this research. The objective of this study was to evaluate some acaricides currently used in citrus orchards, determining their effect on pest mites and predaceous mites (Phytoseiidae) living among the crop. The experiment was carried out in a citrus orchard (Tahitian lime), in the Boa Vista municipality, in the state of Roraima, Brazil. The acaricides studied and their respective concentrations (g a.i./100 l of water) were: mancozeb (200), abamectin (0.36), spirodiclofen (6), sulphur (400) and dimethoate (80). The application was made using tractor-mounted hydraulic handgun sprayers, using a volume of 10 L of acaricide suspension per plant. The statistical design was a completely randomized design with six treatments and five replicates. The evaluations of the effect of chemicals on the populations of S. hindustanicus and predaceous mites (Phytoseiidae) were carried out at 1, 4, 7, 14, 28, 42 and 56 days after treatment (DAT). During each evaluation, 20 leaves and 10 fruits were collected per plot, counting the number of S. hindustanicus and phytoseiid mites. All the chemicals reduced significantly the population of hindustan citrus mite on the leaves until 28 DAT. (AU)

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Espécies de plantas associadas podem servir de abrigo para um grande número de organismo, entre eles ácaros predadores. Este estudo visou identificar as plantas associadas com maior potencial de inimigos naturais, para poder estabelecer formas de controle biológico. O estudo foi realizado nos municípios de Boqueirão do Leão e Dois Lajeados, no período de março de 2006 a fevereiro de 2007 e em Candiota e Bento Gonçalves, no período de outubro de 2006 a setembro de 2007, no Estado do Rio Grande do Sul. Os ácaros foram coletados mensalmente em cinco espécies de plantas comumente encontradas no interior ou nos arredores da cultura de videiras. As plantas foram avaliadas sob microscópio estereoscópico, sendo encontrado um total de 1.036 ácaros das famílias Phytoseiidae, Stigmaeidae e Iolinidae. Foram amostradas 80 espécies de plantas, totalizando 506 amostragens. Em Sonchus oleraceus L, foram encontrados 110 espécimes, em Plantago tomentosa Lam. foram encontrados 105 ácaros, em Chromolaena Laevigata (Lam) R. M. King &H. Rob., 97 ácaros e em Solanum americanum Mill. 75 ácaros. Pronematus anconai Baker, (1943) 1944, foi mais abundante, com 618 espécimes presentes em 44 plantas amostradas, Transeius lisei Ferla & Silva 2008, com 112 espécimes, Typhlodromalus aripo Deleon, 1967, com 50 espécimes e Arrenoseius gaucho Ferla et al. 2010, com 68 espécimes. As espécies de plantas associadas à videira apresentam um grande número de ácaros predadores, sendo que elas podem ser um reservatório de inimigos naturais para controlar ácaros praga nesta cultura. Desta forma, essas plantas podem ser utilizadas em estratégias de onde programas de controle biológico aplicado podem ser utilizados. (AU)

PLANTS ASSOCIATED TO THE GRAPEVINE: A STRATEGY FOR BIOLOGICAL CONTROL IN THE STATE OF RIO GRANDE DO SUL, BRAZIL. Associated plant species can provide shelter for a large number of organisms, including predatory mites. This study aimed to identify the associated plants with the greatest potential for natural enemies, in order to establish forms of biological control. The study was conducted in Boqueirão do Leão and Dois Lajeados counties, from March 2006 to February 2007, and in Candiota and Bento Gonçalves counties, from October 2006 to September 2007, in the state of Rio Grande do Sul, Brazil. The mites were collected monthly on 5 plant species commonly found inside or outside the grapevine crop. The plants were evaluated under a stereoscopic microscope, and a total of 1036 mites of the Phytoseiidae, Stigmaeidae, and Iolinidae families were found. Eighty plant species were sampled, for a total of 506 samples. Examination revealed 110 specimens on Sonchus oleraceus L., 105 on Plantago tomentosaLam., 97 on Chromolaena Laevigata (Lam) R. M. King & H. Rob., and 75 on Solanum americanumMill. Pronematus anconai, 1944, was the most abundant species, with 618 specimens present on 44 plants, followed by Transeius lisei, with 112 specimens, Typhlodromalus aripo Deleon, 1967, with 50 specimens, and Arrenoseius gaucho, Ferla et al. 2010 with 68 specimens. Plants associated to the grapevine have a large number of predatory mites, and they can be a reservoir of natural enemies for the control of pest mites in this crop. Thus, these plants can be used in strategies involving the use of biological control programs. (AU)

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The purpose of this study was to elaborate a preliminary list of the mite species associated with rubber trees in the municipality of Santana, in the state of Amapá, Brazil. Two collections of rubber tree leaves were conducted on May 2nd and June 5th , 2010. Twenty-five plants were sampled at random. Three leaves were collected per plant, from the lower third of the crown. The samples were placed in paper bags, packed in an isothermal box chilled gel-based pulp plant (Gelo-X®), and transported to the Entomology Laboratory at Embrapa Amapá, in Macapá. The leaflets were examined under a stereomicroscope, and the mites found on the adaxial and abaxial surfaces of the leaves were collected with a stilet, mounted on microscope slides in Hoyer's medium, and later identified. We collected a total of 1,722 mites of 10 families: Acaridae, Cunaxidae, Eriophyidae, Iolinidae, Phytoseiidae, Stigmaeidae, Tarsonemidae, Tenuipalpidae, Tydeidae, and Winterschmidtiidae, in addition to unidentified species of the suborders Oribatida and Astigmatina. The family Phytoseiidae represented only 2.90% of specimens collected, but showed the highest species richness (5 species). The only representative of Tenuipalpidae was Tenuipalpus heveae Baker, 1945, but 81.13% of the mites collected in this study belonged to this species.

O objetivo deste estudo foi elaborar uma lista preliminar das espécies de ácaros associadas à seringueira, no município de Santana, Estado do Amapá. Foram realizadas duas coletas de folhas de seringueira, nos dias 2 de maio e 5 de junho de 2010. Foram tomadas aleatoriamente 25 plantas, de cada uma das quais foram coletadas três folhas, no terço inferior da copa. As amostras foram acondicionadas em sacos de papel, mantidas em caixa isotérmica refrigerada com gel à base de celulose vegetal (Gelo-X®) e transportadas até o Laboratório de Entomologia da Embrapa Amapá, em Macapá. A triagem dos folíolos foi realizada com o auxílio de estereomicroscópio. Os ácaros encontrados nas faces adaxial e abaxial das folhas foram capturados com um estilete, montados em lâminas de microscopia em meio de Hoyer e, posteriormente, identificados. Foram coletados 1.722 ácaros, pertencentes a dez famílias: Acaridae, Cunaxidae, Eriophyidae, Iolinidae, Phytoseiidae, Stigmaeidae, Tarsonemidae, Tenuipalpidae, Tydeidae e Winterschmidtiidae, além de espécies não identificadas das subordens Oribatida e Astigmatina. A família Phytoseiidae representou apenas 2,90% do total de espécimes coletados, porém apresentou a maior riqueza em espécies (cinco espécies). A família Tenuipalpidae, embora representada apenas por Tenuipalpus heveae Baker, 1945, apresentou o maior número de espécimes capturados (81,13%).

RESUMO

O ácaro-hindustânico-dos-citros, Schizotetranychus hindustanicus (Hirst), é uma praga de importância quarentenária, recentemente introduzida no Brasil. Até a condução do presente estudo, não havia informações na literatura sobre a eficiência de acaricidas no controle de S. hindustanicus, em condições de campo. O estudo teve por objetivo avaliar o efeito de alguns acaricidas, utilizados em pomares de citros no país, sobre o ácaro-praga e ácaros predadores (Phytoseiidae) presentes na cultura. O experimento foi conduzido em um pomar de citros (limão-tahiti), em Boa Vista, RR. Os acaricidas testados e respectivas concentrações (g i.a./100 L de água) foram: mancozebe (200), abamectina (0,36), espirodiclofeno (6), enxofre (400) e dimetoato (80). A aplicação foi realizada com equipamento acoplado a um trator, provido de pistolas, aplicando-se 10 litros de calda por planta. O delineamento estatístico foi inteiramente casualizado com seis tratamentos e cinco repetições. As avaliações foram realizadas aos 1, 4, 7, 14, 28, 42 e 56 dias após a aplicação (DAA). Em cada avaliação, foram coletados 20 folhas e 10 frutos por parcela, contando-se o número de ácaros S. hindustanicus e fitoseídeos. Todos os produtos reduziram significativamente a população do ácaro-hindustânico nas folhas até 28 DAA. Os acaricidas dimetoato e espirodiclofeno foram altamente eficientes no controle de S. hindustanicus, sendo que o espirodiclofeno apresentou um período de controle mais longo que dimetoato. Com relação aos ácaros predadores, dimetoato, enxofre e abamectina causaram mortalidades significativas (72 a 100%) aos fitoseídeos, até 4 DAA. A espécie predominante de fitoseídeo foi Euseius concordis (Chant), correspondendo a 71% dos ácaros observados.

EFFECT OF ACARICIDES ON SCHIZOTETRANYCHUS HINDUSTANICUS (HIRST) (ACARI: TETRANYCHIDAE) AND PREDACEOUS MITES ON CITRUS IN THE STATE OF RORAIMA, BRAZIL. Schizotetranychus hindustanicus (Hirst) is a pest of quarantine importance, recently introduced in Brazil. There was no information in the literature, on the efficacy of acaricides for the control of S. hindustanicus (Hirst) under field conditions, up to the conduction of this research. The objective of this study was to evaluate some acaricides currently used in citrus orchards, determining their effect on pest mites and predaceous mites (Phytoseiidae) living among the crop. The experiment was carried out in a citrus orchard (Tahitian lime), in the Boa Vista municipality, in the state of Roraima, Brazil. The acaricides studied and their respective concentrations (g a.i./100 l of water) were: mancozeb (200), abamectin (0.36), spirodiclofen (6), sulphur (400) and dimethoate (80). The application was made using tractor-mounted hydraulic handgun sprayers, using a volume of 10 L of acaricide suspension per plant. The statistical design was a completely randomized design with six treatments and five replicates. The evaluations of the effect of chemicals on the populations of S. hindustanicus and predaceous mites (Phytoseiidae) were carried out at 1, 4, 7, 14, 28, 42 and 56 days after treatment (DAT). During each evaluation, 20 leaves and 10 fruits were collected per plot, counting the number of S. hindustanicus and phytoseiid mites. All the chemicals reduced significantly the population of hindustan citrus mite on the leaves until 28 DAT.

Assuntos

RESUMO

Espécies de plantas associadas podem servir de abrigo para um grande número de organismo, entre eles ácaros predadores. Este estudo visou identificar as plantas associadas com maior potencial de inimigos naturais, para poder estabelecer formas de controle biológico. O estudo foi realizado nos municípios de Boqueirão do Leão e Dois Lajeados, no período de março de 2006 a fevereiro de 2007 e em Candiota e Bento Gonçalves, no período de outubro de 2006 a setembro de 2007, no Estado do Rio Grande do Sul. Os ácaros foram coletados mensalmente em cinco espécies de plantas comumente encontradas no interior ou nos arredores da cultura de videiras. As plantas foram avaliadas sob microscópio estereoscópico, sendo encontrado um total de 1.036 ácaros das famílias Phytoseiidae, Stigmaeidae e Iolinidae. Foram amostradas 80 espécies de plantas, totalizando 506 amostragens. Em Sonchus oleraceus L, foram encontrados 110 espécimes, em Plantago tomentosa Lam. foram encontrados 105 ácaros, em Chromolaena Laevigata (Lam) R. M. King &H. Rob., 97 ácaros e em Solanum americanum Mill. 75 ácaros. Pronematus anconai Baker, (1943) 1944, foi mais abundante, com 618 espécimes presentes em 44 plantas amostradas, Transeius lisei Ferla & Silva 2008, com 112 espécimes, Typhlodromalus aripo Deleon, 1967, com 50 espécimes e Arrenoseius gaucho Ferla et al. 2010, com 68 espécimes. As espécies de plantas associadas à videira apresentam um grande número de ácaros predadores, sendo que elas podem ser um reservatório de inimigos naturais para controlar ácaros praga nesta cultura. Desta forma, essas plantas podem ser utilizadas em estratégias de onde programas de controle biológico aplicado podem ser utilizados.

PLANTS ASSOCIATED TO THE GRAPEVINE: A STRATEGY FOR BIOLOGICAL CONTROL IN THE STATE OF RIO GRANDE DO SUL, BRAZIL. Associated plant species can provide shelter for a large number of organisms, including predatory mites. This study aimed to identify the associated plants with the greatest potential for natural enemies, in order to establish forms of biological control. The study was conducted in Boqueirão do Leão and Dois Lajeados counties, from March 2006 to February 2007, and in Candiota and Bento Gonçalves counties, from October 2006 to September 2007, in the state of Rio Grande do Sul, Brazil. The mites were collected monthly on 5 plant species commonly found inside or outside the grapevine crop. The plants were evaluated under a stereoscopic microscope, and a total of 1036 mites of the Phytoseiidae, Stigmaeidae, and Iolinidae families were found. Eighty plant species were sampled, for a total of 506 samples. Examination revealed 110 specimens on Sonchus oleraceus L., 105 on Plantago tomentosaLam., 97 on Chromolaena Laevigata (Lam) R. M. King & H. Rob., and 75 on Solanum americanumMill. Pronematus anconai, 1944, was the most abundant species, with 618 specimens present on 44 plants, followed by Transeius lisei, with 112 specimens, Typhlodromalus aripo Deleon, 1967, with 50 specimens, and Arrenoseius gaucho, Ferla et al. 2010 with 68 specimens. Plants associated to the grapevine have a large number of predatory mites, and they can be a reservoir of natural enemies for the control of pest mites in this crop. Thus, these plants can be used in strategies involving the use of biological control programs.

Assuntos

RESUMO

Associated plant species can provide shelter for a large number of organisms, including predatory mites. This study aimed to identify the associated plants with the greatest potential for natural enemies, in order to establish forms of biological control. The study was conducted in Boqueirão do Leão and Dois Lajeados counties, from March 2006 to February 2007, and in Candiota and Bento GONÇALVES counties, from October 2006 to September 2007, in the state of Rio Grande do Sul, Brazil. The mites were collected monthly on 5 plant species commonly found inside or outside the grapevine crop. The plants were evaluated under a stereoscopic microscope, and a total of 1036 mites of the Phytoseiidae, Stigmaeidae, and Iolinidae families were found. Eighty plant species were sampled, for a total of 506 samples. Examination revealed 110 specimens on Sonchus oleraceus L., 105 on Plantago tomentosa Lam., 97 on Chromolaena Laevigata (Lam) R. M. King & H. Rob., and 75 on Solanum americanum Mill. Pronematus anconai, 1944, was the most abundant species, with 618 specimens present on 44 plants, followed by Transeius lisei, with 112 specimens, Typhlodromalus aripo Deleon, 1967, with 50 specimens, and Arrenoseius gaucho, FERLA et al. 2010 with 68 specimens. Plants associated to the grapevine have a large number of predatory mites, and they can be a reservoir of natural enemies for the control of pest mites in this crop. Thus, these plants can be used in strategies involving the use of biological control programs.

Espécies de plantas associadas podem servir de abrigo para um grande número de organismo, entre eles ácaros predadores. Este estudo visou identificar as plantas associadas com maior potencial de inimigos naturais, para poder estabelecer formas de controle biológico. O estudo foi realizado nos municípios de Boqueirão do Leão e Dois Lajeados, no período de março de 2006 a fevereiro de 2007 e em Candiota e Bento GONÇALVES, no período de outubro de 2006 a setembro de 2007, no Estado do Rio Grande do Sul. Os ácaros foram coletados mensalmente em cinco espécies de plantas comumente encontradas no interior ou nos arredores da cultura de videiras. As plantas foram avaliadas sob microscópio estereoscópico, sendo encontrado um total de 1.036 ácaros das famílias Phytoseiidae, Stigmaeidae e Iolinidae. Foram amostradas 80 espécies de plantas, totalizando 506 amostragens. Em Sonchus oleraceus L, foram encontrados 110 espécimes, em Plantago tomentosa Lam. foram encontrados 105 ácaros, em Chromolaena Laevigata (Lam) R. M. King &H. Rob., 97 ácaros e em Solanum americanum Mill. 75 ácaros. Pronematus anconai BAKER, (1943) 1944, foi mais abundante, com 618 espécimes presentes em 44 plantas amostradas, Transeius lisei FERLA & SILVA 2008, com 112 espécimes, Typhlodromalus aripo Deleon, 1967, com 50 espécimes e Arrenoseius gaucho FERLA et al. 2010, com 68 espécimes. As espécies de plantas associadas à videira apresentam um grande número de ácaros predadores, sendo que elas podem ser um reservatório de inimigos naturais para controlar ácaros praga nesta cultura. Desta forma, essas plantas podem ser utilizadas em estratégias de onde programas de controle biológico aplicado podem ser utilizados.

RESUMO

Schizotetranychus hindustanicus (Hirst) is a pest of quarantine importance, recently introduced in Brazil. There was no information in the literature, on the efficacy of acaricides for the control of S. hindustanicus (Hirst) under field conditions, up to the conduction of this research. The objective of this study was to evaluate some acaricides currently used in citrus orchards, determining their effect on pest mites and predaceous mites (Phytoseiidae) living among the crop. The experiment was carried out in a citrus orchard (Tahitian lime), in the Boa Vista municipality, in the state of Roraima, Brazil. The acaricides studied and their respective concentrations (g a.i./100 l of water) were: mancozeb (200), abamectin (0.36), spirodiclofen (6), sulphur (400) and dimethoate (80). The application was made using tractor-mounted hydraulic handgun sprayers, using a volume of 10 L of acaricide suspension per plant. The statistical design was a completely randomized design with six treatments and five replicates. The evaluations of the effect of chemicals on the populations of S. hindustanicus and predaceous mites (Phytoseiidae) were carried out at 1, 4, 7, 14, 28, 42 and 56 days after treatment (DAT). During each evaluation, 20 leaves and 10 fruits were collected per plot, counting the number of S. hindustanicus and phytoseiid mites. All the chemicals reduced significantly the population of hindustan citrus mite on the leaves until 28 DAT. The acaricides dimethoate and spirodiclofen were highly effective against S. hindustanicus, and spirodiclofen presented a longer effective period than dimethoate. Regarding the predaceous mites, dimethoate, sulfur and abamectin caused significant mortality (72 to 100%) to the predators up to 4 DAT. The predominant species of Phytoseiid mite was Euseius concordis (Chant), corresponding to 71% of mites of this family.

O ácaro-hindustânico-dos-citros, Schizotetranychus hindustanicus (Hirst), é uma praga de importância quarentenária, recentemente introduzida no Brasil. Até a condução do presente estudo, não havia informações na literatura sobre a eficiência de acaricidas no controle de S. hindustanicus, em condições de campo. O estudo teve por objetivo avaliar o efeito de alguns acaricidas, utilizados em pomares de citros no país, sobre o ácaro-praga e ácaros predadores (Phytoseiidae) presentes na cultura. O experimento foi conduzido em um pomar de citros (limão-tahiti), em Boa Vista, RR. Os acaricidas testados e respectivas concentrações (g i.a./100 L de água) foram: mancozebe (200), abamectina (0,36), espirodiclofeno (6), enxofre (400) e dimetoato (80). A aplicação foi realizada com equipamento acoplado a um trator, provido de pistolas, aplicando-se 10 litros de calda por planta. O delineamento estatístico foi inteiramente casualizado com seis tratamentos e cinco repetições. As avaliações foram realizadas aos 1, 4, 7, 14, 28, 42 e 56 dias após a aplicação (DAA). Em cada avaliação, foram coletados 20 folhas e 10 frutos por parcela, contando-se o número de ácaros S. hindustanicus e fitoseídeos. Todos os produtos reduziram significativamente a população do ácaro-hindustânico nas folhas até 28 DAA. Os acaricidas dimetoato e espirodiclofeno foram altamente eficientes no controle de S. hindustanicus, sendo que o espirodiclofeno apresentou um período de controle mais longo que dimetoato. Com relação aos ácaros predadores, dimetoato, enxofre e abamectina causaram mortalidades significativas (72 a 100%) aos fitoseídeos, até 4 DAA. A espécie predominante de fitoseídeo foi Euseius concordis (Chant), correspondendo a 71% dos ácaros observados.

RESUMO

Mites of the families Eriophyidae, Tarsonemidae and Tetranychidae are considered of economic importance in the blackberry (Rubus fruticosus, Rosaceae), raspberry and other small fruit crops. This study was conducted from November of 2001 to October of 2003 on Brazos, Caigangue and Tupy cultivars in Ilópolis municipality, state of Rio Grande do Sul, to describe the mitefauna and its population fluctuation in blackberry crops. A total of 36,094 mites belonging to 12 families was collected. Most of the mites belong to Diptilomiopidae (80.9%) and Tetranychidae (13.9%), composed predominantly of phytophagous species. Chakrabartiella sp. (Diptilomiopidae) was the most abundant species, followed by Neotetranychus asper Feres & Flechtmann, 2000 (Tetranychidae). Stigmaeidae (2.1%) and Phytoseiidae (0.4%) were the most common families of predaceous mites, and Agistemus brasiliensis Matioli, Ueckermann & Oliveira, 2002 (Stigmaeidae) and Typhlodromalus aripo DeLeon, 1967 (Phytoseiidae) the most common predaceous species.

Ácaros das famílias Eriophyidae, Tarsonemidae e Tetranychidae são citados como de importância econômica na cultura de amora-preta (Rubus fruticosus, Rosaceae), framboesa e outras frutas pequenas. Este estudo foi conduzido de novembro de 2001 a outubro de 2003 nas cultivares Brazos, Caigangue e Tupy no município de Ilópolis, Rio Grande do Sul, com o objetivo de conhecer a acarofauna e sua dinâmica populacional em amora-preta. Foram coletados 36.094 ácaros pertencentes a 11 famílias. A maioria dos ácaros coletados pertence às famílias Diptilomiopidae (80,9%) e Tetranychidae (13,9%), compostas por espécies fitófagas. Chakrabartiella sp. (Diptilomiopidae), foi a espécie mais abundante, seguida por Neotetranychus asper Feres & Flechtmann, 2000 (Tetranychidae). Stigmaeidae (2,1%) e Phytoseiidae (0,4%) foram os ácaros predadores mais comuns, sendo Agistemus brasiliensis Matioli, Ueckermann & Oliveira, 2002 (Stigmaeidae) e Typhlodromalus aripo DeLeon, 1967 (Phytoseiidae), as espécies de predadores mais abundantes.

RESUMO

Mites of the families Eriophyidae, Tarsonemidae and Tetranychidae are considered of economic importance in the blackberry (Rubus fruticosus, Rosaceae), raspberry and other small fruit crops. This study was conducted from November of 2001 to October of 2003 on Brazos, Caigangue and Tupy cultivars in Ilópolis municipality, state of Rio Grande do Sul, to describe the mitefauna and its population fluctuation in blackberry crops. A total of 36,094 mites belonging to 12 families was collected. Most of the mites belong to Diptilomiopidae (80.9%) and Tetranychidae (13.9%), composed predominantly of phytophagous species. Chakrabartiella sp. (Diptilomiopidae) was the most abundant species, followed by Neotetranychus asper Feres & Flechtmann, 2000 (Tetranychidae). Stigmaeidae (2.1%) and Phytoseiidae (0.4%) were the most common families of predaceous mites, and Agistemus brasiliensis Matioli, Ueckermann & Oliveira, 2002 (Stigmaeidae) and Typhlodromalus aripo DeLeon, 1967 (Phytoseiidae) the most common predaceous species.

Ácaros das famílias Eriophyidae, Tarsonemidae e Tetranychidae são citados como de importância econômica na cultura de amora-preta (Rubus fruticosus, Rosaceae), framboesa e outras frutas pequenas. Este estudo foi conduzido de novembro de 2001 a outubro de 2003 nas cultivares Brazos, Caigangue e Tupy no município de Ilópolis, Rio Grande do Sul, com o objetivo de conhecer a acarofauna e sua dinâmica populacional em amora-preta. Foram coletados 36.094 ácaros pertencentes a 11 famílias. A maioria dos ácaros coletados pertence às famílias Diptilomiopidae (80,9%) e Tetranychidae (13,9%), compostas por espécies fitófagas. Chakrabartiella sp. (Diptilomiopidae), foi a espécie mais abundante, seguida por Neotetranychus asper Feres & Flechtmann, 2000 (Tetranychidae). Stigmaeidae (2,1%) e Phytoseiidae (0,4%) foram os ácaros predadores mais comuns, sendo Agistemus brasiliensis Matioli, Ueckermann & Oliveira, 2002 (Stigmaeidae) e Typhlodromalus aripo DeLeon, 1967 (Phytoseiidae), as espécies de predadores mais abundantes.