RESUMO
Microsporidia are natural pathogens of arthropods and have been used as biological control against insect pests. In the United States, efforts to control the invasive Red Imported Fire Ant, Solenopsis invicta, and Black Imported Fire Ant, Solenopsis richteri, have included the use of the microsporidium, Kneallhazia solenopsae. However, there is limited information about the genetic differences among the microsporidian variants found in S. invicta and in S. richteri. In this study, we assessed the prevalence and genetic diversity of K. solenopsae in native populations of S. richteri in Argentina (South America). Additionally, we examined the social parasitic ant, Solenopsis daguerrei, which is found in some S. richteri nests, for the presence of this microsporidium. The survey of 219 S. richteri nests revealed K. solenopsae infections in all five sites analyzed, with 28 colonies (12.8%) positive for the microsporidium. Among the 180 S. daguerrei individuals collected, seven ants (3.9%) from three sites tested positive for K. solenopsae. Phylogenetic analyses of the microsporidian variants present in S. richteri and S. daguerrei based on partial small subunit ribosomal gene sequences (SSU rRNA) showed that both ant species shared the same variant, which is different from the ones found in S. invicta. Further studies are needed to determine the pathogenicity of genetically different K. solenopsae variants among Solenopsis species.
RESUMO
We evaluated the efficacy and residual toxicity of nine commercial insecticides on Plutella xylostella and their selectivity to the predator ant Solenopsis saevissima under laboratory and field conditions. First, to test the insecticides' effectiveness and selectivity, we conducted concentration-response bioassays on both species and the mortalities were recorded 48 h after exposure. Next, rapeseed plants were sprayed following label rate recommendations in the field. Finally, insecticide-treated leaves were removed from the field up to 20 days after application and both organisms were exposed to them as in the first experiment. Our concentration-response bioassay indicated that seven insecticides caused mortality ≥80% of P. xylostella: bifenthrin, chlorfenapyr, chlorantraniliprole, cyantraniliprole, indoxacarb, spinetoram, and spinosad. However, only chlorantraniliprole and cyantraniliprole caused mortality ≤30% of S. saevissima. The residual bioassay indicated that four insecticides had a long-lasting effect, causing mortality of 100% to P. xylostella 20 days after application: chlorantraniliprole, cyantraniliprole, spinetoram, and spinosad. For S. saevissima, bifenthrin caused mortality of 100% during the evaluated period. Additionally, mortality rates below 30% occurred four days after the application of spinetoram and spinosad. Thus, chlorantraniliprole and cyantraniliprole are safe options for P. xylostella management since their efficacy favor S. saevissima.
RESUMO
ABSTRACT The excessive use of chemical insecticides has led to negative effects on human health and the environment. Volatile oils are one of the possible potential alternatives to chemical insecticides. Traditionally Seriphidium brevifolium (Wall. ex DC.) Ling & Y.R.Ling, Asteraceae, powder from its leaves is used to treat gastric problems and expel intestinal worms by local peoples, but yet there is no literature available regarding its insecticidal activity. In this study fumigant toxicity and enzyme inhibition activities of the S. brevifolium volatile oil collected from the highlands of Skardu Baltistan, Pakistan, was evaluated against the red imported fire ant Solenopsis invicta. The phytochemical studies indicated that monoterpenes were the most abundant constituents, accounting for 88% of the total oil. The major dominant constituents were 2-bornanone (28.2%), 1,8-cineole (19.9%), α-thujone (7.5%), β-thujone (6.7%) which accounts for 62.3% of total constituents identified, with volatile oil yield of 4.11% (w/w). The fumigation assay indicated that the volatile oil was acutely toxic to fire ants, with an LC50 of 16.47 µl/l. Among the constituents tested, only (α + β) thujone and 1,8-cineole were toxic, with LC50 of 17.68 and 30.66 µl/ after 12 h of exposure. The volatile oil, (α + β) thujone and 1, 8-cineole showed strong fumigant activity against the red imported fire ant workers in a time- and dose-dependent manner. The volatile oil caused 100% mortality of the red imported fire ant workers, even at the lowest concentration of 20 µl/l after 24 h of exposure. In addition, the volatile oil and 1,8-cineole inhibited acetylcholinesterase activity, while (α + β) thujone inhibited carboxylesterase activity in the fire ant workers. It has been concluded that the volatile oil and some of the compounds from S. brevifolium might be developed as eco-friendly approaches for the control of red imported fire ants.
RESUMO
As formigas lava-pés são facilmente encontradas em ambientes urbanos e, devido ao seu comportamento agressivo, ferroam suas vítimas, o que pode desencadear reações alérgicas graves ou até mesmo a morte do indivíduo. O controle dessas formigas ainda não é bem estabelecido, no entanto, é possível encontrar diversas alternativas de controle tanto na internet como na literatura. Sendo assim, o objetivo desse trabalho foi realizar um levantamento quantitativo acerca dos métodos de controle de lava-pés disponíveis nas diferentes mídias de divulgação. A pesquisa foi realizada nas plataformas do Google e YouTube para sites e vídeos, respectivamente, e Web of Science e Google Acadêmico para produções científicas, nos últimos 22 anos. Os termos utilizados na pesquisa foram como controlar formigas lava-pés em sites e vídeos e fire ants, control, Brazil para a busca bibliográfica. Os métodos sugeridos para o controle de formigas de fogo foram divididos em três categorias: caseiros, químicos e controle biológico. Um total de 38 publicações (18 sites, 12 vídeos e oito produções bibliográficas) que abordaram 18 métodos diferentes de controle foram registrados. Os métodos caseiros foram os mais citados (n = 39), seguido dos métodos químicos (n = 19) e controle biológico (n = 2). Dentre os sites encontrados, o uso de substâncias de origem vegetal (n = 7) foi o mais citado, já a maioria dos vídeos acessados sugeriram uma solução de vinagre com detergente (n = 5) e nas produções bibliográficas o uso de inseticidas (n = 4) foi mais recomendado. Houve participação de profissionais em 61% das publicações. Embora a internet seja um instrumento de pesquisa popular, é necessário atentar-se à confiabilidade das informações disponibilizadas, visto que o manuseio de determinados produtos pode ser nocivo à saúde e ao meio ambiente e em muitos casos ser totalmente ineficaz para o controle destas formigas.
The fire ants are easily found in urban environments, and because of their aggressive behavior, they sting their victims, which can trigger serious allergic reactions or even death. The control of these ants is still not well established, however, it is possible to find several control alternatives both in the internet and in the literature. Therefore, the objective of this work was to perform a quantitative survey on the methods of control of fire ants available in the different media of disclosure. The survey was conducted on Google and YouTube platforms for websites and videos, respectively, and Web of Science and Google Scholar for scientific productions, in the past 22 years. The terms used in the research were "how to control fire ants in websites and videos and "fire ants, control, Brazil" for the bibliography search. The methods found were divided into three categories: homemade, chemical and biological control. A total of 38 publications (18 sites, 12 videos and eight bibliographic productions) that addressed 18 different methods of control were recorded. The homemade methods were the most cited (n = 39), followed by chemical methods (n = 19) and biological control (n = 2). Among the sites found, the use of substances of vegetable origin (n = 7) was the most cited, and most of the videos accessed suggested a solution of vinegar with detergent (n = 5) and in the bibliographical productions the use of insecticides (n = 4) was more recommended. There was participation of professionals in 61% of the publications. Although the internet is a popular research instrument, it is necessary to take into account the reliability of the information provided, since the handling of certain products can be harmful to health and the environment and in many cases be totally ineffective for the control of these ants.
Assuntos
Animais , Controle Biológico de Vetores , Controle de Pragas , FormigasRESUMO
As formigas lava-pés são facilmente encontradas em ambientes urbanos e, devido ao seu comportamento agressivo, ferroam suas vítimas, o que pode desencadear reações alérgicas graves ou até mesmo a morte do indivíduo. O controle dessas formigas ainda não é bem estabelecido, no entanto, é possível encontrar diversas alternativas de controle tanto na internet como na literatura. Sendo assim, o objetivo desse trabalho foi realizar um levantamento quantitativo acerca dos métodos de controle de lava-pés disponíveis nas diferentes mídias de divulgação. A pesquisa foi realizada nas plataformas do Google e YouTube para sites e vídeos, respectivamente, e Web of Science e Google Acadêmico para produções científicas, nos últimos 22 anos. Os termos utilizados na pesquisa foram como controlar formigas lava-pés em sites e vídeos e fire ants, control, Brazil para a busca bibliográfica. Os métodos sugeridos para o controle de formigas de fogo foram divididos em três categorias: caseiros, químicos e controle biológico. Um total de 38 publicações (18 sites, 12 vídeos e oito produções bibliográficas) que abordaram 18 métodos diferentes de controle foram registrados. Os métodos caseiros foram os mais citados (n = 39), seguido dos métodos químicos (n = 19) e controle biológico (n = 2). Dentre os sites encontrados, o uso de substâncias de origem vegetal (n = 7) foi o mais citado, já a maioria dos vídeos acessados sugeriram uma solução de vinagre com detergente (n = 5) e nas produções bibliográficas o uso de inseticidas (n = 4) foi mais recomendado. Houve participação de profissionais em 61% das publicações. Embora a internet seja um instrumento de pesquisa popular, é necessário atentar-se à confiabilidade das informações disponibilizadas, visto que o manuseio de determinados produtos pode ser nocivo à saúde e ao meio ambiente e em muitos casos ser totalmente ineficaz para o controle destas formigas.(AU)
The fire ants are easily found in urban environments, and because of their aggressive behavior, they sting their victims, which can trigger serious allergic reactions or even death. The control of these ants is still not well established, however, it is possible to find several control alternatives both in the internet and in the literature. Therefore, the objective of this work was to perform a quantitative survey on the methods of control of fire ants available in the different media of disclosure. The survey was conducted on Google and YouTube platforms for websites and videos, respectively, and Web of Science and Google Scholar for scientific productions, in the past 22 years. The terms used in the research were "how to control fire ants in websites and videos and "fire ants, control, Brazil" for the bibliography search. The methods found were divided into three categories: homemade, chemical and biological control. A total of 38 publications (18 sites, 12 videos and eight bibliographic productions) that addressed 18 different methods of control were recorded. The homemade methods were the most cited (n = 39), followed by chemical methods (n = 19) and biological control (n = 2). Among the sites found, the use of substances of vegetable origin (n = 7) was the most cited, and most of the videos accessed suggested a solution of vinegar with detergent (n = 5) and in the bibliographical productions the use of insecticides (n = 4) was more recommended. There was participation of professionals in 61% of the publications. Although the internet is a popular research instrument, it is necessary to take into account the reliability of the information provided, since the handling of certain products can be harmful to health and the environment and in many cases be totally ineffective for the control of these ants.(AU)
Assuntos
Animais , Formigas , Controle Biológico de Vetores , Controle de PragasRESUMO
In this study, conducted in French Guiana, a part of the native range of the fire ant Solenopsis saevissima, we compared the cuticular hydrocarbon profiles of media workers with previous results based on intraspecific aggressiveness tests. We noted a strong congruence between the two studies permitting us to delimit 2 supercolonies extending over large distances (up to 54 km), a phenomenon known as unicoloniality. Solenopsis geminata workers, taken as an out-group for cluster analyses, have a very different cuticular hydrocarbon profile. Because S. saevissima has been reported outside its native range, our conclusion is that this species has the potential to become invasive because unicoloniality (i.e., the main attribute for ants to become invasive) was shown at least for the Guianese population.
Assuntos
Formigas/fisiologia , Animais , Formigas/química , Guiana Francesa , Hidrocarbonetos/análise , Espécies IntroduzidasRESUMO
Supercolonies of the red fire ant Solenopsis saevissima (Smith) develop in disturbed environments and likely alter the ant community in the native range of the species. For example, in French Guiana only 8 ant species were repeatedly noted as nesting in close vicinity to its mounds. Here, we verified if a shared set of biological, ecological, and behavioral traits might explain how these 8 species are able to nest in the presence of S. saevissima. We did not find this to be the case. We did find, however, that all of them are able to live in disturbed habitats. It is likely that over the course of evolution each of these species acquired the capacity to live syntopically with S. saevissima through its own set of traits, where colony size (4 species develop large colonies), cuticular compounds which do not trigger aggressiveness (6 species) and submissive behaviors (4 species) complement each other.