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1.
J Econ Entomol ; 110(2): 333-346, 2017 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-28069631

RESUMO

Pollinator-dependent agriculture heavily relies upon a single pollinator-the honey bee. To diversify pollination strategies, growers are turning to alternatives. Densely planted reservoirs of pollen- and nectar-rich flowers (pollination reservoirs, hereafter "PRs") may improve pollination services provided by wild bees. Our focal agroecosystem, lowbush blueberry (Vaccinium angustifolium Aiton), exists in a simple landscape uniquely positioned to benefit from PRs. First, we contrast bee visitation rates and use of three types of PR. We consider the effects of PRs on wild bee diversity and the composition of bumble bee pollen loads. We contrast field-level crop pollination services between PRs and controls four years postestablishment. Last, we calculate the time to pay for PR investment. Social bees preferentially used clover plantings; solitary bees preferentially used wildflower plantings. On average, bumble bee pollen loads in treatment fields contained 37% PR pollen. PRs significantly increased visitation rates to the crop in year 4, and exerted a marginally significant positive influence on fruit set. The annualized costs of PRs were covered by the fourth year using the measured increase in pollination services. Our findings provide evidence of the positive impact of PRs on crop pollination services.


Assuntos
Agricultura/métodos , Abelhas/fisiologia , Mirtilos Azuis (Planta)/fisiologia , Polinização , Animais , Biodiversidade , Flores/fisiologia , Maine
2.
Environ Entomol ; 39(5): 1428-40, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22546437

RESUMO

Over a period of 19 yr, the harvestman (Opiliones) community associated with the lowbush blueberry agro-ecosystem in Maine was studied. Eight species representing five genera, four subfamilies, and two families of harvestmen belonging to the suborder Eupnoi were collected. The harvestman community was dominated by two introduced, synanthropic species: Phalangium opilio in all but 1 yr (that year dominated by Rilaena triangularis). Rilaena was recorded for the first time from eastern North America. Relative abundance of harvestman adults increases throughout the season and the temporal pattern of trap capture does not refute speculated life cycles of the harvestmen being univoltine with overwintering eggs. Some blueberry management practices were found to affect trap capture. We did find that on average (with opposite results 1 yr) trap captures are greater in pruned fields than in fruit-bearing fields. Organic fields were found to have higher relative abundance of harvestmen than conventionally managed fields. Conventionally managed fields with reduced-risk insecticides showed no difference in harvestmen relative abundance compared with those conventionally managed fields using the older more persistent organophosphate insecticides. Insecticide trials with common insecticides used in blueberry insect pest management showed that the organophosphate insecticide, phosmet, and the pyrethroid insecticide, esfenvalerate, were detrimental to P. opilio adults when exposed to leaf residues, whereas the reduced-risk insecticide, spinosad, showed no negative effects compared with nonsprayed foliage.


Assuntos
Aracnídeos/fisiologia , Mirtilos Azuis (Planta) , Animais , Aracnídeos/crescimento & desenvolvimento , Biota , Meio Ambiente , Cadeia Alimentar , Controle de Insetos/métodos , Inseticidas/efeitos adversos , Maine , Ninfa/crescimento & desenvolvimento , Ninfa/fisiologia , Óvulo/crescimento & desenvolvimento , Óvulo/fisiologia , Dinâmica Populacional , Estações do Ano , Especificidade da Espécie
3.
Recurso na Internet em Português | LIS - Localizador de Informação em Saúde | ID: lis-21476

RESUMO

Com a participação de autoridades na área de medicina do esporte do país o documento traz um posicionamento oficial sobre o tema “Atividade Física e Saúde”, com os objetivos de: estabelecer os benefícios da atividade física; caracterizar os elementos de avaliação e prescrição do exercício para a saúde; instrumentalizar os profissionais de saúde para o uso eficiente da atividade física.


Assuntos
Saúde Pública , Atividade Motora , Exercício Físico , Esportes , Qualidade de Vida , Promoção da Saúde
4.
J Econ Entomol ; 94(3): 609-16, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11425013

RESUMO

The pollination effectiveness of the commercially reared bumble bee Bombus impatiens Cresson, was compared in field studies to the honey bee, Apis mellifera L., for lowbush blueberry, Vaccinium angustifolium Ait. A preliminary study indicated that B. impatiens had potential as an alternative pollinator. In a 3-yr study, percentage fruit set, percentage harvested berries, berry weight, and seeds per berry were compared in blueberry fields stocked at 7.5 A. mellifera hives per hectare to 5, 7.5, or 10 B. impatiens colonies per hectare. Percentage of harvested berries (yield) was significantly higher in fields stocked with B. impatiens at 10 colonies per hectare. No other parameters measuring pollinator effectiveness were significantly different at 5, 7.5, or 10 colonies per hectare. Flower handling time was significantly faster for B. impatiens and it more frequently collected blueberry pollen. All parameters of pollinator effectiveness were similar for B. impatiens, A. mellifera, and native wild bees in a follow-up study. Overall, B. impatiens was a suitable alternative to A. mellifera.


Assuntos
Abelhas , Comportamento Animal , Pólen , Animais
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