56 research outputs found
ForĂdeos cleptoparasitas de abelhas-sem-ferrĂŁo: sazonalidade, distribuição espacial e atratividade de iscas de vinagre.
Este estudo teve como objetivos verificar a abundância e a sazonalidade de moscas cleptoparasitas de abelhas-sem-ferrĂŁo da famĂlia Phoridae, em Rio Branco, AC, assim como a eficácia de diferentes iscas de vinagre na captura dessas moscas. TrĂŞs mĂ©todos de amostragem foram utilizados: a) armadilhas instaladas a diferentes distâncias do meliponário, contendo pĂłlen de abelha-sem-ferrĂŁo, ou vinagre de vinho tinto ou ambos; b) armadilhas instaladas ao lado de colmeias com isca de vinagre de vinho tinto, de maçã ou álcool; c) contagem do nĂşmero de forĂdeos dentro das colmeias. Foram amostrados 1.050 espĂ©cimes, sendo a maioria (92%) coletada em armadilhas. A espĂ©cie Pseudohypocera kerteszi representou 98% dos espĂ©cimes capturados nas armadilhas. A maior abundância de forĂdeos capturados ocorreu na estação chuvosa, com pico em dezembro. Verificou-se uma correlação positiva entre o nĂşmero de forĂdeos contados dentro das colĂ´nias e o nĂşmero de forĂdeos capturados nas armadilhas. Estes foram mais frequentes nas armadilhas com pĂłlen colocadas na área do meliponário, apresentando uma distribuição agregada. Em função disso, recomenda-se a manutenção das colĂ´nias enfraquecidas a, pelo menos, 20 metros dos locais de criação de abelhas-sem-ferrĂŁo. Os vinagres de vinho tinto ou de maçã apresentaram atratividade semelhante, podendo ambos ser usados como isca.bitstream/item/64718/1/24346.pd
Frugivory by a stingless bee (Hymenoptera: Apidae).
Frugivory is not frequent among bees. Although stingless bees visit aged fruits for pulp, the use of fresh fruits is recorded only for Trigona hypogea Silvestri, a species that does not visit flowers. Here we report the occurrence of frugivory in Trigona amazonensis (Ducke), a flowervisiting stingless bee
Abelhas-sem-ferrĂŁo e espĂ©cies vegetais com potencial apĂcola em quintais agroflorestais do Acre.
O objetivo principal deste trabalho foi realizar um levantamento de espĂ©cies arbĂłreas com potencial apĂcola em dez quintais localizados em áreas de assentamento rural no estado do Acre. AlĂ©m das avaliações agronĂ´micas, foram amostrados, semanalmente, os insetos que estavam visitando as flores em um dos quintais. Constatou-se que 100% das propriedades avaliadas cultivam de forma integrada espĂ©cies frutĂferas, medicinais, hortaliças, condimentares e ornamentais. As frutĂferas predominaram, representando 72,3% das plantas cultivadas. Das espĂ©cies com potencial apĂcola, o Cajueiro (Anacardium occidentale L.) foi encontrado em nove quintais, Urucum (Bixa orellana L.) em seis e Ingá-cipĂł (Inga edulis Mart) em todos os avaliados. Quanto aos insetos, foram coletados 376 indivĂduos de sete ordens. A Ordem Hymenoptera totalizou 73,7% dos insetos amostrados. Destes, 57,14% foram abelhas-sem-ferrĂŁo dos gĂŞneros Aparatrigona, Geotrigona, Melipona, Partamona, Tetragona, Tetragonisca, Trigona
Associação entre abelhas-sem-ferrĂŁo (Hymenoptera: Apidae: Meliponina) e Aetalion reticulatum (L.) (Hemiptera: Aethalionidae) em plantio de açaĂ-de-touceira.
Aetalion reticulatum (L.) (Hemiptera: Aethalionidae), conhecida popularmente por cigarrinha-das-frutĂferas, cigarrinha-dos-pomares ou cigarrinha-dopedĂşnculo, Ă© um inseto fitĂłfago, cujas ninfas e adultos atacam diferentes espĂ©cies vegetais. Em março de 2014, no Campo Experimental da Embrapa Acre, foi observada a associação entre abelhas-sem-ferrĂŁo e colĂ´nias de A. reticulatum em cachos de açaĂ-de-touceira (Euterpe oleracea Martius)
Doubly Uniparental Inheritance of Mitochondria As a Model System for Studying Germ Line Formation
BACKGROUND: Doubly Uniparental Inheritance (DUI) of mitochondria occurs when both mothers and fathers are capable of transmitting mitochondria to their offspring, in contrast to the typical Strictly Maternal Inheritance (SMI). DUI was found in some bivalve molluscs, in which two mitochondrial genomes are inherited, one through eggs, the other through sperm. During male embryo development, spermatozoon mitochondria aggregate in proximity of the first cleavage furrow and end up in the primordial germ cells, while they are dispersed in female embryos. METHODOLOGY/PRINCIPAL FINDINGS: We used MitoTracker, microtubule staining and transmission electron microscopy to examine the mechanisms of this unusual distribution of sperm mitochondria in the DUI species Ruditapes philippinarum. Our results suggest that in male embryos the midbody deriving from the mitotic spindle of the first division concurs in positioning the aggregate of sperm mitochondria. Furthermore, an immunocytochemical analysis showed that the germ line determinant Vasa segregates close to the first cleavage furrow. CONCLUSIONS/SIGNIFICANCE: In DUI male embryos, spermatozoon mitochondria aggregate in a stable area on the animal-vegetal axis: in organisms with spiral segmentation this zone is not involved in cleavage, so the aggregation is maintained. Moreover, sperm mitochondria reach the same embryonic area in which also germ plasm is transferred. In 2-blastomere embryos, the segregation of sperm mitochondria in the same region with Vasa suggests their contribution in male germ line formation. In DUI male embryos, M-type mitochondria must be recognized by egg factors to be actively transferred in the germ line, where they become dominant replacing the Balbiani body mitochondria. The typical features of germ line assembly point to a common biological mechanism shared by DUI and SMI organisms. Although the molecular dynamics of the segregation of sperm mitochondria in DUI species are unknown, they could be a variation of the mechanism regulating the mitochondrial bottleneck in all metazoans
Pervasive gaps in Amazonian ecological research
Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4
While the increasing availability of global databases on ecological communities has advanced our knowledge
of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In
the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of
Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus
crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced
environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian
Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by
2050. This means that unless we take immediate action, we will not be able to establish their current status,
much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio
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