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Polimorfismo do fungo simbionte de formigas cortadeiras submetido à luz ultravioleta
Borba, Regina da Silva;Loeck, Alci Enimar;Branco, Juliana Severo Castelo;Kopp, Maurício Marini;Oliveira, Ant?nio Costa de;
Ciência Rural , 2007, DOI: 10.1590/S0103-84782007000500001
Abstract: the present research was aimed at verifing the effect of different periods of ultraviolet light on the development of the symbiont fungus of leaf cutting ants belonging to the species acromyrmex ambiguus, acromyrmex crassispinus and acromyrmex lundi, through the aflp technique. the fungus were inoculated in pagnocca's medium and maintained in climatized cameras at 25 + 1°c and 24 hours of darkness, for a period of 15 days. after that, they were exposed to ultraviolet light for 0, 5, 10, 15, 20, 25, and 30 minutes. at 45 days after the treatment, the extraction and standardization of dna was performed. pcr reactions were tested using 24 aflp primer combinations, from which four were selected because they presented larger polymorfism and consistence. the molecular data were transformed in binary mattrix and analyzed by the statistical program ntsys v. 2.1. the four combinations of primers generated 152 polymorfic bands. the fungus populations from different acromyrmex species presented a medium genetic similarity of the 37%, and the mutations induced by the ultraviolet light allowed to obtain more dissimilar isolates.
Variabilidade genética interespecífica em formigas cortadeiras do gênero Acromyrmex que ocorrem no Estado do Rio Grande do Sul
Grutzmacher, Douglas Daniel;Loeck, Alci Enimar;Oliveira, Ant?nio Costa;Zimmer, Paulo Dejalma;Malone, Gaspar;
Ciência Rural , 2007, DOI: 10.1590/S0103-84782007000400001
Abstract: at present, a few number of taxonomists work on identification of leaf cutting ants. morphological-based methods do not always produce a reliable identification, due to the strong polymorphism observed even in the same colony. this fact leads to hypothesize that, besides those variations, others may also occur related to geographic distribution of the ants. six acromyrmex species were sampled at four locations in the state of rio grande do sul and analyzed by rapd and aflp. fifty ubc primers, originated from the university of british columbia, were evaluated to select a set of primers that could be useful for species identification and genetic variability studies. only 13 primers, which amplified fragments of all species, were selected. although the selected primers produced fragments that allowed various ways for identification of a. heyeri, a. ambiguus, a. crassispinus, a. striatus, a. laticeps and a. aspersus, only ubc 354, ubc348 and ubc356 primers allowed a reliable identification showing the most visible fragments. results by dendogram and morphological-based identification, showed that a. striatus and a. laticeps are less related to the other species. however a. ambiguus e a. crassispinus are the most genetically related ants in the state of rio grande do sul. the results indicate that a reliable identification of acromyrmex can be carried out by rapd and aflp, yet allowing verification of genetic distance between species.
OCORRêNCIA DE FORMIGAS CORTADEIRAS NA REGI O DA DEPRESS O CENTRAL DO ESTADO DO RIO GRANDE DO SUL  [cached]
Grürzmacher Douglas D.,Loeck Alci Enimar,Medeiros Ane H.
Ciência Rural , 2002,
Abstract: Com o objetivo de identificar as espécies de formigas cortadeiras que existem na regi o da Depress o Central do Estado do Rio Grande do Sul, de verificar sua predominancia e distribui o geográfica, realizou-se um levantamento em 51 municípios. Foram coletadas 40 amostras de formigas de cada município no segundo semestre de 1999. A identifica o das formigas e a interpreta o dos dados foi realizada no Departamento de Fitossanidade da Faculdade de Agronomia "Eliseu Maciel" da Universidade Federal de Pelotas. Na análise das 2.058 amostras de formigas, constatou-se a presen a de: Atta sexdens piriventris Santschi, 1919; Acromyrmex laticeps (Emery, 1905); Acromyrmex crassispinus (Forel, 1909); Acromyrmex heyeri (Forel, 1899); Acromyrmex lundi (Guerin, 1838); Acromyrmex ambiguus (Emery, 1887); Acromyrmex striatus (Roger, 1863); Acromyrmex lobicornis (Emery, 1887); Acromyrmex coronatus (Fabricius, 1804) e Acromyrmex landolti balzani Emery, 1890. As espécies predominantes foram Acromyrmex lundi, Atta sexdens piriventris, A. ambiguus, A. heyeri, A. striatus e A. laticeps, representando, respectivamente, 23,91%, 22,89%, 16,86%, 14,04%, 6,85% e 6,70% do total amostrado, ocorrendo em 84,31%, 60,78%, 70,59%, 84,31%, 78,43% e 88,24% dos municípios, respectivamente. As demais espécies (A. crassispinus, A. lobicornis, A. landolti balzani e A. coronatus) foram pouco freqüentes, representando juntas 6,27% do total, sendo por isso, consideradas de ocorrência rara nesta regi o.
Combate sistemático de formigas-cortadeiras com iscas granuladas, em eucaliptais com cultivo mínimo  [cached]
Zanetti Ronald,Zanuncio José Cola,Mayhé-Nunes Ant?nio José,Medeiros Alex Giovanny Barros
Revista árvore , 2003,
Abstract: Avaliou-se a eficiência do combate sistemático de formigas-cortadeiras em áreas de reforma de eucalipto com cultivo mínimo, na Celulose Nipo-Brasileira S.A., em Belo Oriente, Minas Gerais, de setembro a dezembro de 1996. Os tratamentos consistiram na aplica o de uma isca granulada com sulfluramida (0,3%) de forma sistemática, a granel ou com microporta-iscas, na dosagem de 5 g a cada 6 m2 e 10 g a cada 12 m2, respectivamente. A mortalidade das col nias de formigas-cortadeiras foi avaliada 30 dias após a aplica o da isca. Foram encontradas até 396,3, 285,2, 59,3, 55,6, 29,6 e 14,8 col nias de Mycocepurus goeldii, Sericomyrmex sp., Acromyrmex subterraneus molestans, Atta spp., Acromyrmex balzani e Acromyrmex niger (Hymenoptera: Formicidae) por hectare, respectivamente. A eficiência da isca granulada no combate sistemático variou com o método empregado e com a espécie de formiga-cortadeira. A maior eficiência foi obtida para A. subterraneus molestans, com 69,2% de suas col nias mortas com a isca aplicada a granel e 62,5% com microporta-iscas, o que indica que a distribui o entre dois pontos com isca nos plantios de eucalipto foi maior que a área de forrageamento das formigas-cortadeiras encontradas e, ou, que a dosagem aplicada por ponto foi insuficiente.
Protocolo de experimenta??o para avaliar a atratividade de novas formula??es de iscas granuladas utilizadas no controle das formigas cortadeiras Acromyrmex spp. e Atta spp. (Hymenoptera: Formicidae: Myrmicinae: Attini) no campo
Delabie, Jacques H.C.;Lucia, Terezinha Della;Pastre, Lionel;
Anais da Sociedade Entomológica do Brasil , 2000, DOI: 10.1590/S0301-80592000000400029
Abstract: we present hereafter a protocol to test attractiveness of new formulations of granulated baits used against leaf-cutting ants (acromyrmex spp. and atta spp.) in the field. its purpose is to standardize the methodology, thus making possible further comparison of results wherever these tests are carried out
Plano de amostragem de Acromyrmex spp. (Hymenoptera: Formicidae) em áreas de pré-plantio de Pinus spp  [cached]
Cantarelli Edison Bisognin,Costa Ervandil Corrêa,Zanetti Ronald,Pezzutti Raul
Ciência Rural , 2006,
Abstract: Realizou-se um estudo para elaborar um plano de amostragem de formigas cortadeiras em área de pré-plantio florestal, na empresa Bosques del Plata situada no Departamento de Santo Tomé, província de Corrientes, Argentina. O trabalho teve como objetivo estudar a distribui o espacial de formigueiros do gênero Acromyrmex em área de pré-plantio de Pinus spp., determinar o tamanho ótimo de parcelas e estimar a intensidade amostral desse gênero de formigas. Concluiu-se que a distribui o espacial dos ninhos de Acromyrmex spp. em Corrientes-Argentina, se ajusta ao modelo casual, com o tamanho ótimo de parcela para amostrar a densidade de formigueiros (ninhos.ha-1) de 700m2 (10x70m) e a intensidade amostral ótima de 10,5% da área total para um erro esperado de 24%.
Efeito de extratos naturais de folhas vegetais em Leucoagaricus gongylophorus (M ller) Singer, (Agaricales: Agaricaceae) / Effect of natural extracts of vegetable leaves in Leucoagaricus gongylophorus (M ller) Singer, (Agaricales: Agaricaceae)  [cached]
Marcelo Dias Souza,Otávio Peres Filho,Alberto Dorval
Ambiência , 2011,
Abstract: O estudo teve como objetivo avaliar os efeitos dos extratos naturais, à base de folhas de diferentes espécies vegetais, em Leucoagaricus gongylophorus, fungo simbionte de formigas cortadeiras. O experimento foi realizado no Laboratório de Prote o Florestal, da Faculdade de Engenharia Florestal, da Universidade Federal de Mato Grosso, sob temperatura média 26 ± 2oC, e umidade relativa de 70 ± 10%. Os tratamentos avaliados foram os extratos aquosos a 10% (peso/volume) de dez diferentes espécies vegetais. Foram realizados onze tratamentos, sendo que para cada um foi utilizado um recipiente de 1,5 l de volume, colocado na parte central contendo fungo e formigas, no qual era interligado com mais dois recipientes, de igual volume, interligados entre si por um tubo plástico, propiciando condi es necessárias para que as formigas desenvolvessem suas atividades normais. O fungo e as formigas cortadeiras, após coletados, foram transferidos para os recipientes em laboratório. Assim que os formigueiros artificiais apresentavam atividades normais, os extratos foram adicionados diretamente sobre o fungo, com exce o da testemunha. Os tratamentos que tiveram efeito deletério sobre o fungo, em ordem decrescente foram os à base de Tabebuia vellosoi (ipê-amarelo-liso), Azadirachta indica (Nim), Magonia pubescens (Timbó), Annona reticulata (Pinha) e Amburana acreana (cerejeira).AbstractThe objective of this study was to evaluate the effects of natural extracts of leaves of different plant species, in Leucoagaricus gongylophorus, symbiotic fungus of leaf-cutting ants. The experiment was conducted at the Laboratory of Forest Protection, Federal University from Mato Grosso, on average temperature 26 ± 2o C and relative humidity of 70 ± 10%. The treatments evaluated were the aqueous extracts of 10% (weight/volume) of ten different plant species. It was carried out 11 treatments, and for each one a container of 1.5 l volume was used, placed in the central part containing fungus and ants, and it was linked with two more containers with the same volume, interconnected by a plastic tube, providing necessary conditions for the ants to develop their common activities. The fungus and the leaf-cutting ants, after collected, were transferred to the containers in the laboratory. Once the artificial ant nests showed common activities, the extracts were added directly on the fungus, with except of the stands. The treatment that had effect deleterious on the fungus, in descending order were the base of Tabebuia vellosoi (ipe-yellow-flat), Azadirachta indica (Neem), Magonia pubescens (Tim
Combate sistemático de formigas-cortadeiras com iscas granuladas, em eucaliptais com cultivo mínimo
Zanetti, Ronald;Zanuncio, José Cola;Mayhé-Nunes, Ant?nio José;Medeiros, Alex Giovanny Barros;Souza-Silva, Alan;
Revista árvore , 2003, DOI: 10.1590/S0100-67622003000300016
Abstract: the efficiency of a systematic application of baits against leaf-cutting ants was evaluated in a eucalypus plantation under a minimum cultivation system, in areas owned by celulose nipo-brasileira s.a. (cenibra), in belo oriente, minas gerais, brazil, from september to december 1996. treatments consisted of applying a granulated bait with sulfluramide (0.3%) in a systematic manner in bulk and plastic bags at a dose of five grams every 6 m2 (t1) and 10 grams at each 12 m2 (t2). mortality of colonies of leaf-cutting ants was evaluated 30 days after bait application. a. maximum of 396.3; 285.2; 59.3; 55.6; 29.6 and 14.8 colonies of mycocepurus goeldii, sericomyrmex sp., acromyrmex subterraneus molestans, atta spp., acromyrmex balzani and acromyrmex niger (hymenoptera: formicidae), respectively, was found per hectare. the efficiency of this granulated bait, applied in a systematic manner, varied with the method and species of leaf-cutting ants. higher efficiency was obtained for a. subterraneus molestans, with 69.2% of dead colonies with the bait applied in bulk and 62.5% when it was applied in plastic bags. this shows that bait distribution in the eucalyptus plantation was performed at a larger spacing than the foraging area of leaf-cutting ants and/or that the dose was insufficient.
OCORRêNCIA DE FORMIGAS CORTADEIRAS NA REGI?O DA DEPRESS?O CENTRAL DO ESTADO DO RIO GRANDE DO SUL
Grürzmacher, Douglas D.;Loeck, Alci Enimar;Medeiros, Ane H.;
Ciência Rural , 2002, DOI: 10.1590/S0103-84782002000200001
Abstract: with the objective of to identifying the leaf-cutting ants that occur in the depress?o central region of rio grande do sul state, brazil, to verify its predominance species and its geographical distribution, a survey was done in 51 counties. forty ant samples were collected in each county in second semester of 1999. ants identification and data interpretation were carried out in the fitossanidade department of "eliseu maciel" agronomy faculty of the federal university of pelotas. ants from 2.058 samples were identified, being observed: atta sexdens piriventris santschi, 1919; acromyrmex laticeps (emery, 1905); acromyrmex crassispinus (forel, 1909); acromyrmex heyeri (forel, 1899); acromyrmex lundi (guerin, 1838); acromyrmex ambiguus (emery, 1887); acromyrmex striatus (roger, 1863); acromyrmex lobicornis (emery, 1887); acromyrmex coronatus (fabricius, 1804) and acromyrmex landolti balzani (forel, 1884). the predominant species were acromyrmex lundi, atta sexdens piriventris, a. ambiguus, a. heyeri, a. striatus and a. laticeps, representing, respectively, 23.91%, 22.89%, 16.86%, 14.04%, 6.85% and 6.70% of total samples in this region, occurring in 84.31%, 60.78%, 70.59%, 84.31%, 78.43% and 88.24% of the counties, respectively. the others species (a. crassispinus, a. lobicornis, a. landolti balzani and a. coronatus) are less frequent, representing together 6.27% of total samples, being considered of rare occurrence in this region.
Damage caused by different levels of artificial defoliation, simulating the leaf-cutting ants attack on young plantations of Pinus taeda and Eucalyptus grandis Danos causados por diferentes níveis de desfolha artificial para simula o do ataque de formigas cortadeiras em Pinus taeda e Eucalyptus grandis
Wilson Reis Filho,Franciele dos Santos,Priscila Strapasson,Mariane Aparecida Nickele
Pesquisa Florestal Brasileira , 2011, DOI: 10.4336/2012.pfb.65.37
Abstract: The artificial defoliation allows to measure the defoliation intensity caused by insects. The objectives of this work were to evaluate the damages caused by leaf-cutting ants in young plantations of Pinus taeda and Eucalyptus grandis using different levels of artificial defoliation. A classification was established according to defoliation levels that were caused by leaf-cutting ants in P. taeda: level 1: 50%, level 2: 75%, level 3: 100% and level 4: 100%, including the cut of the apical meristem. And in E. grandis: level 1: 50% of defoliation; level 2: 75% and level 3: 100%. After one year, the P. taeda seedlings had losses in diameter and height for defoliation level above 75%. Seedlings severely defoliated (level 4), had losses of 37.0% in height and 45.4% in diameter. The E. grandis seedlings had losses since three months old and the reductions were proportional to the defoliation intensity. After one year, the losses of 13.3% in height and 20% in diameter were verified in plants with 100% of defoliation. P. taeda plants are more damaged by leaf-cutting attack. doi: 10.4336/2011.pfb.31.65.37 A desfolha artificial permite mensurar a intensidade do dano devido à desfolha causada por insetos. No presente estudo, buscou-se avaliar os danos causados por formigas cortadeiras em plantios de Pinus taeda e Eucalyptus grandis com 30 dias de idade. Foi estabelecida uma classifica o baseada em níveis de desfolha semelhantes aos causados por formigas cortadeiras. Para P. taeda, os níveis foram: N1: 50%, N2: 75%, N3: 100% e N4: 100% de desfolha, incluindo o corte do meristema apical. Para E. grandis, os níveis foram N1: 50%, N2: 75% e N3: 100% de desfolha, incluindo o corte do meristema apical. Após um ano, as mudas de P. taeda tiveram perdas em altura e diametro nos níveis de N2 a N4. Mudas de P. taeda desfolhadas no nível N4 apresentaram perdas de 37,0% em altura e 45,4% em diametro. As mudas de E. grandis apresentaram perdas aos três meses de idade, sendo estas proporcionais à intensidade de desfolha. Após um ano, verificaram-se perdas de 13,3% em altura e 20% em diametro, nas plantas de P. taeda que tiveram 100% de desfolha. Plantas de P. taeda foram mais prejudicadas pela simula o do ataque de formigas cortadeiras do que as de E. grandis.
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