Extrato metanólico de folhas de mandioca como alternativa ao controle da lagarta-do-cartucho e de formigas cortadeiras

The objective of this study was to characterize phenolic compounds and evaluate the effect, under laboratory conditions, of the cassava leaf powder methanol extract on the development of fall armyworm Spodoptera frugiperda and of leaf-cutting ant Atta sexdens rubropilosa. The extract was incorporated into an artificial diet, to which the armyworm was exposed, at concentrations of 250, 500, 1000 and 1500 mg kg-1,in order to evaluate biological characteristics. Soon after the insects emergence, another experiment was conducted to verify the possible sub lethal activity of the extract; therefore, S. frugiperda couples were isolated in cages and eggs were collected and counted. The Manihot esculenta Crantz extract caused a reduction in the percentage of armyworm survival, as well as in the eggs number. Then, the same extract was solubilized in 10% ethanol and applied to ants; mortality was observed, compared to the control. It is possible to conclude that the M. esculenta Crantz leaf powder methanolic extract, containing gallic acid and catechin, is a promising alternative to control S. frugiperda and Atta sexdens rubropilosa.

Natureza do parasitismo de Escovopsis e Escovopsioides sobre Leucoagaricus gongylophorus, fungos associados aos jardins de formigas cortadeiras

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Fungos melanizados associados a formigas cortadeiras (Formicidae: Tribo Attini)

Leafcutter ants are considered pests in agriculture for their impact in human crops, as they behave utilizing foliar fragments to raise their simbiont fungi (Agaricales: Lepiotaceae) inside their nest. Recent studies have noticed that other fungi may be associated to ants inside their nests, for instance, fungi with melanized wall, known by “dematiaceous”. Historically, many black fungi have been noticed as fitopathogens of many plant cultures with economic importance, highlighting dematiaceous ecological behavior importance in this study. This investigation had the purpose of amplifying ecological knowledge of this fungi, isolating and identificating dematiaceous fungi found in Attini nests, having the intention of understanding plant pathogens dispersion by ants. In this work, 66 isolates were characterized in the following genus: Aspergillus, Penicillium, Paecilomyces, Oxyporus, Rhodotorula, Bipolaris, Curvularia, Fusarium, Giberella, Paraphaeosphaeria, and Cladosporium. The genus Bipolaris, Curvularia, Fusarium and Giberella are known for their opportunistic behaviour, with some published human infections in literature. Fusarium is a notorious fitopathogen, with wide number of descriptions and studies involving pathogenicity development, biochemistry and genetics. The isolates outline is of phyto – associated (phytopathogens, endophytic or epiphitic), fulfilling this work intention in alarming fungi capacity of dispersal by ants. The comprehension of phytopathogenical processes may be clarified based on the knowledge of oportunistics fungi that may utilize ants bodies for their own dispersal. The identification of isolates with capacity of infecting humans brings out public health issues.

Patogenicidade de Syncephalastrum racemosum nos jardins de formigas cortadeiras

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

O jardim de fungo atua como um molde para a construção das câmaras em formigas cortadeiras?

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Influência do ambiente no desenvolvimento de colônias iniciais de formigas cortadeiras (Atta sexdens rubropilosa)

Annually, mature colonies of Atta ants produce winged males and females, where leave the colony in which they were produced to form new colonies and thus continue the species perpetuation. The foundation of Atta spp. colonies always involves high queen effort, solely responsible for growing the fungus and the care with itself and its offspring. During the foundation there is consumption of body reserves. This study investigated how the environment influences the development of newly founded colonies of leaf cutting ant, Atta sexdens rubropilosa. Therefore, it was compared field colonies collected five months after the nuptial flight and colonies maintained in the laboratory since the nuptial flight. It was analyzed the weight and size of the population (number of workers, larvae, pupae and eggs), the workers size, the volume and weight of the fungus garden and queen effort for the nest foundation (lipid content and weight of queens). In comparison to the field colonies, the laboratory colonies showed higher values in the weight and size of population, the volume and weight of the fungus garden. Measures of workers by class size did not vary between colonies from field and laboratory. The queen effort for nest foundation was higher in field colonies, which showed a lower percentage of fat and lower weight compared to laboratory colonies. These results show that the environment has a strong influence on the colonies development during the foundation, as well as on the physiological status of the queens, and therefore the survival, development and success of the colony, it is a reflection of the queen efforts and of the environment conditions.

Identificação de inibidores de pectinase fúngica para o controle de formigas cortadeiras

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Caracterização das trilhas de forrageamento em formigas cortadeiras de gramíneas (Formicidae, Attini): transferência de informações durante o recrutamento em Atta bisphaerica

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Validação de sistema de amostragem para monitoramento de formigas cortadeiras atta spp. (Hymenoptera: formicidae) em plantações de eucalipto

Pós-graduação em Ciência Florestal - FCA

Controle de formigas cortadeiras (Hymenoptera: Formicidae) com produtos naturais

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Seleção de ingredientes ativos para o desenvolvimento de iscas tóxicas para o controle de formigas-cortadeiras (Hymenoptera: Formicidae)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Semioquímicos e comunicação sonora em formigas cortadeiras (Hymenoptera: Formicidae)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Comunidades de fungos em jardins de formigas cortadeiras com diferentes hábitos de forrageamento

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Papel de Syncephalastrum racemosum como antagonista do fungo cultivado pelas formigas cortadeiras

Currently, the major method for controlling leaf-cutting ants uses toxic baits containing the insecticide sulfluramide. Such compound presents harmful effects to the environment and to human health, which drive the community’s concerns towards new strategies for controlling these insects. Previous studies showed the occurrence of Syncephalastrum racemosum in nests of the leaf-cutting ants submitted to treatments using insecticides. In order to understand the role of S. racemosum in nests of leaf-cutting ants, the present work investigated the antagonism of S. racemosum towards the leaf-cutting ant-cultivar (Leucoagaricus gongylophorus). Using in vitro essays, we co-cultivated L. gongylophorus and S. racemosum (n= 6 lineages). For comparison, we also used the same setup to test one strain of Escovopsis weberi, since this fungus is considered a specialized parasite of the leaf-cutting ant cultivar. All S. racemosum strains inhibited the growth of L. gongylophorus (ANOVA 2 way, F= 23,61, P< 0,01). The same was observed for E. weberi. There were no significant difference between S. racemosum and E. weberi inhibition (Bonferroni test, P> 0,05). In addition, we verified that all S. racemosum strains colonized and sporulated over the fungus garden up to 96 h after garden fragments without workers were inoculated with spores suspensions. Similar results were observed on gardens that were inoculated with spores of E. weberi. The results indicate that S. racemosum act as antagonist of the leaf-cutting ant cultivar. The putative possibility for using S. racemosum as biological control agent of leaf-cutting ants is discussed in the present work

Fungos fitopatógenos associados às formigas cortadeiras (Formicidae: Tribo Attini)

The ants of genus Atta belong to the Attine tribe (order Hymenoptera, family Formicidae, subfamily Myrmicinae) and are commonly known as leaf-cutting ants for having the habit of cutting several vegetable species used as substrate for growing mutualistic fungus (Agaricales: Lepiotaceae). Recent studies showed that, in addition to that, other fungi may occur in the nests in a dorment state or participate in the functioning dynamic of this symbiosis. Researches related to surveys of fungus biodiversity in nests of different Atta species have found important phytopathogenic representatives. In Brazil, studies about integrated management of plagues, developed by Embrapa Meio Ambiente (Embrapa Environment), point out the need of higher investments in projects that involve the phytopathogenic transmission by insects in order to reduce costs to control them or minimize environmental impact. The purpose of this study was to broaden the knowledge about the ecology of these fungi, isolating and identifying species associated with Attine tribe ants, thus understanding the scope of pathogenic and phytopathogenic species spread by these ants. For that reason, gynes were collected from Atta laevigata and Atta capiguara anthills located at Unesp Botucatu (São Paulo, Brazil) campus. In order to isolate the fungus, the mineral oil floating technique was used. The identification of the isolated fungi was done based on microscopic and molecular characteristics using DNA ribosomal sequencing. The most highly abundant genera found so far were: Cladosporium, Exophiala, Penicillium, Acremonium, Phialophora and Teratosphaeria. Representatives of the genera Exophiala, Phialophora and Cladosporium may be human pathogens, whereas Teratosphaeria and Penicillium are related to diseases in Eucalyptus and citric fruits, respectively. The results show that these ants may host important fungal species besides the ones already... (Complete abstract click electronic access below)