The impact of coffee and pasture agriculture on predatory and omnivorous leaf-litter ants.

Ants are known to function as reliable biological indicators for habitat impact assessment. They play a wide range of ecological roles depending on their feeding and nesting habits. By clustering ants in guilds, it is possible both to assess how agriculture and forest fragmentation can disturb ant communities and to predict the ecological impacts due to losses of a specific guild. This study aimed at determining the impact of non-shaded coffee and pasture agriculture on predatory and omnivorous guilds of leaf-litter ants of Atlantic Forest fragments in Minas Gerais, Brazil. Both coffee and pasture agriculture influenced leaf-litter ant community, although coffee was more disruptive than pasture. Coffee agriculture not only disturbed the diversity of predatory ants, but also negatively affected the number of predatory and omnivorous ants when compared to forest fragments. In contrast, pasture agriculture only disrupted the abundance of predatory ants. Fragment edges skirting crops were negatively affected in terms of leaf-litter ant abundance, but not diversity. Cluster analysis showed that forest fragments were similar irrespective of the cultivation, but the borders were similar to the crop. The study assessed agriculture impact by surveying ant guilds, and revealed that the predatory guild is more susceptible than omnivorous ants.

Primeiro registro de Pachycoris torridus (Scopoli, 1772) (Hemiptera: Scutelleridae) em pinhão-manso (Euphorbiaceae) em Alagoas, Brasil / First record of Pachycoris torridus (Scopoli, 1772) (Hemiptera: Scutelleridae) on physic nut (Euphorbiaceae) in Alagoas, Brazil

Notifica-se a ocorrência de Pachycoris torridus (Scopoli, 1772) (Hemiptera: Scutelleridae) em Igaci (Alagoas), atacando a cultura de pinhão-manso, Jatropha curcas L. O inseto, até então não constatado na região, assume relevância econômica pela natureza dos danos, ocasionando infestação em 100 por cento das plantas.

The occurrence of Pachycoris torridus (Scopoli) (Hemiptera: Scutelleridae) in Igaci (in the state of Alagoas, Brazil), is observed attacking the physic nut (Jatropha curcas L.) The insect, until then not verified in the region, takes economic relevancy considering the nature of damage, causing infestation in 100 percent plants.

[Action of extract and oil neem in the control of Rhipicephalus (Boophilus) microplus (Canestrini, 1887) (Acari: Ixodidae) in laboratory]. / Ação de extrato e óleo de nim no controle de Rhipicephalus (Boophilus) microplus (Canestrini, 1887) (Acari: Ixodidae) em laboratório.

Organic plant extracts and emulsified oil of Azadirachta indica A. Juss (Meliaceae) (neem) were studied to evaluate its effects in control of engorged females of Rhipicephalus (Boophilus) microplus (Canestrini, 1887) in the laboratory. Hexane and alcoholic organic extracts, 2% (weight/volume) were used in tests of immersion for 5 minutes, prepared with seeds, solubilized in dimethylsulfoxide (DMSO) to 1%. The experiment was entirely randomized, consisting of 6 treatments and 5 replicates, each represented by 5 ticks. Control groups consisted of untreated females. Based on the results of this work, we can indicate that the seed extract (hexanic fraction) and óleo emulsionável I¹ concentration to 2% have significant adjuvant potential to control the cattle tick, because, cause the mortality in the first days after the treatment and interfere in the reproduction, showing to be an alternative to acaricides normally used.

Tabela de vida de fertilidade de três espécies neotropicais de Trichogrammatidae em ovos de hospedeiros alternativos como critério de seleção hospedeira / Fertility life table of three neotropical species of Trichogrammatidae on factitious hosts as a criterion for selection of hosts

Tabela de vida de fertilidade de três espécies neotropicais de Trichogrammatidae em ovos de hospedeiros alternativos como critério de seleção hospedeira. O objetivo deste trabalho foi selecionar o hospedeiro alternativo que permita o melhor desenvolvimento das três espécies neotropicais de tricogramatídeos, Trichogramma atopovirilia Oatman & Platner, 1983; Trichogramma bruni Nagaraja, 1983 e Trichogrammatoidea annulata De Santis, 1972, utilizando-se como parâmetro comparativo as tabelas de vida de fertilidade nos respectivos hospedeiros. Foram estimados a duração média de uma geração (T), taxa líquida de reprodução (Ro), razão infinitesimal (r m) e a razão finita de aumento (λ). A tabela de vida de fertilidade pode ser utilizada para selecionar o hospedeiro alternativo mais adequado para as espécies de tricogramatídeos. Corcyra cephalonica (Stainton, 1865) (Lepidoptera, Pyralidae) foi o hospedeiro alternativo mais adequado para criação de T. annulata e de T. bruni, enquanto que para T. atopovirilia, Anagasta kuehniella (Zeller, 1879) (Lepidoptera, Pyralidae) e/ou C. cephalonica foram os hospedeiros mais adequados. Sitotroga cerealella (Olivier, 1819) (Lepidoptera, Gelechiidae) apresentou baixa capacidade de aumento populacional para as três espécies de parasitóides, sendo, portanto, uma espécie inadequada como hospedeiro alternativo para as mesmas.

The objective of this work was to select the factitious host that permit the best development of three neotropical Trichogrammatidae species, Trichogramma atopovirilia Oatman & Platner, 1983; Trichogramma bruni Nagaraja, 1983, and Trichogrammatoidea annulata De Santis, 1972, using the fertility life table on their respective hosts as a comparative parameter. Mean generation time (T), net reproductive rate (Ro), intrinsic rate of natural increase (r m) and the finite rate of increase (λ) were estimated. A fertility life table is useful to select the most adequate factitious hosts for the trichogrammatid species. Corcyra cephalonica (Stainton, 1865) (Lepidoptera, Pyralidae) was the most suitable factitious host for rearing of T. annulata and T. bruni; while Anagasta kuehniella (Zeller, 1879) (Lepidoptera, Pyralidae) and/or C. cephalonica were the most suitable hosts for T. atopovirilia. Sitotroga cerealella (Olivier, 1819) (Lepidoptera, Gelechiidae) presented a low capacity of population increase for the three species of parasitoids, therefore, being an inadequate species as a factitious host.

Ação de extrato e óleo de nim no controle de Rhipicephalus (Boophilus) microplus (Canestrini, 1887) (Acari: Ixodidae) em laboratório / Action of extract and oil neem in the control of Rhipicephalus (Boophilus) microplus (Canestrini, 1887) (Acari: Ixodidae) in laboratory

Extratos vegetais orgânicos e óleos emulsionáveis de Azadirachta indica A. Juss (Meliaceae) (nim) foram estudados com o objetivo de avaliar seus efeitos no controle de fêmeas ingurgitadas de Rhipicephalus (Boophilus) microplus (Canestrini, 1887) em laboratório. Foram utilizados extratos orgânicos hexânicos e alcoólicos a 2 por cento (peso/volume), em testes de imersão, durante 5 minutos, preparados com sementes, solubilizados em dimetilsulfóxido (DMSO) a 1 por cento. O experimento foi inteiramente casualizado, sendo constituído por 6 tratamentos e 5 repetições, cada uma delas representada por 5 carrapatos. O grupo controle consistiu de fêmeas sem tratamento. Com base nos resultados deste trabalho, pode-se indicar que os tratamentos extrato de semente (hexano) e óleo emulsionável I¹, em concentração a 2 por cento, possuem significativo potencial adjuvante de controle do carrapato bovino, pois ocasionam a mortalidade nos primeiros dias após o tratamento e interferem na reprodução, mostrando ser uma alternativa aos carrapaticidas normalmente utilizados.

Organic plant extracts and emulsified oil of Azadirachta indica A. Juss (Meliaceae) (neem) were studied to evaluate its effects in control of engorged females of Rhipicephalus (Boophilus) microplus (Canestrini, 1887) in the laboratory. Hexane and alcoholic organic extracts, 2 percent (weight/volume) were used in tests of immersion for 5 minutes, prepared with seeds, solubilized in dimethylsulfoxide (DMSO) to 1 percent. The experiment was entirely randomized, consisting of 6 treatments and 5 replicates, each represented by 5 ticks. Control groups consisted of untreated females. Based on the results of this work, we can indicate that the seed extract (hexanic fraction) and óleo emulsionável I1 concentration to 2 percent have significant adjuvant potential to control the cattle tick, because, cause the mortality in the first days after the treatment and interfere in the reproduction, showing to be an alternative to acaricides normally used.

[Plant extracts in control of Rhipicephalus (Boophilus) microplus (Canestrini, 1887) (Acari: Ixodidae) in laboratory]. / Extratos de plantas no controle de Rhicephalus (Boophilus) microplus (Canestrini, 1887) (Acari: Ixodidae) em laboratorio.

Plant extracts were studied to evaluate its efficiency in the control of Rhipicephalus (Boophilus) microplus (Canestrini, 1887) in laboratory. Engorged female ticks were collected from the cattle, kept in Petri dishes. Organic alcoholic extracts 2% (weight/volume) were used: seeds of Annona muricata L. (Annonaceae) (soursop); flowers of Syzygium malaccensis (L.) (Myrtaceae) (iamb), leaves of Cymbopogon citratus (DC.) Stapf (Poaceae) (holy grass), leaves of Azadirachta indica A. Juss (Meliaceae) (neem) and hexane extract 2% (weight/volume) of A. indica (seeds). The control groups consisted of untreated females and females treated with distilled water and sterile and dimethylsulfoxide (DMSO) a concentration of 1%. The extract of A. muricata (seed) had the highest mortality with acaricide activity and 100% efficacy followed by extracts of S. malaccensis (75 and 59.24%) and A. indica (65 and 38.49%). The seed extract of A. muricata reduced 100% larvae hatch.

Extratos de plantas no controle de Rhipicephalus (Boophilus) microplus (Canestrini, 1887) (Acari: Ixodidae) em laboratório / Plant extracts in control of Rhipicephalus (Boophilus) microplus (Canestrini, 1887) (Acari: Ixodidae) in laboratory

Extratos vegetais foram estudados com o objetivo de avaliar suas eficiências no controle de Rhipicephalus (Boophilus) microplus (Canestrini, 1887) em laboratório. Fêmeas ingurgitadas de carrapato foram coletadas de bovinos e mantidas em placas de Petri. Foram utilizados extratos orgânicos alcoólicos 2 por cento (peso/volume) de sementes de Annona muricata L. (Annonaceae) (graviola); flores de Syzygium malaccensis (L.) (Myrtaceae) (jambo); folhas de Cymbopogon citratus (DC.) Stapf (Poaceae) (capim-santo); folhas de Azadirachta indica A. Juss (Meliaceae) (nim); e extrato hexânico na mesma concentração de A. indica (sementes). Os grupos-controle foram compostos por fêmeas sem tratamento e fêmeas tratadas com água destilada e esterilizada e dimetilsulfóxido (DMSO) a uma concentração de 1 por cento. O extrato de A. muricata apresentou o maior poder acaricida, com eficácia de 100 por cento, seguido dos extratos de S. malaccensis (75 e 59,24 por cento) e A. indica (65 e 38,49 por cento). Houve 100 por cento de redução na eclosão das larvas quando se utilizou o extrato de sementes de A. muricata.

Plant extracts were studied to evaluate its efficiency in the control of Rhipicephalus (Boophilus) microplus (Canestrini, 1887) in laboratory. Engorged female ticks were collected from the cattle, kept in Petri dishes. Organic alcoholic extracts 2 percent (weight/volume) were used: seeds of Annona muricata L. (Annonaceae) (soursop); flowers of Syzygium malaccensis (L.) (Myrtaceae) (iamb), leaves of Cymbopogon citratus (DC.) Stapf (Poaceae) (holy grass), leaves of Azadirachta indica A. Juss (Meliaceae) (neem) and hexane extract 2 percent (weight/volume) of A. indica (seeds). The control groups consisted of untreated females and females treated with distilled water and sterile and dimethylsulfoxide (DMSO) a concentration of 1 percent. The extract of A. muricata (seed) had the highest mortality with acaricide activity and 100 percent efficacy followed by extracts of S. malaccensis (75 and 59.24 percent) and A. indica (65 and 38.49 percent). The seed extract of A. muricata reduced 100 percent larvae hatch.