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1.
BMC Ecol ; 20(1): 8, 2020 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-32039719

RESUMO

BACKGROUND: Breeding programs and research activities where artificial buzz-pollinations are required to have primarily relied upon using tuning forks, and bumble bees. However, these methods can be expensive, unreliable, and inefficient. To find an alternative, we tested the efficiency of pollen collection using electric toothbrushes and compared it with tuning forks at three vibration frequencies-low, medium, and high and two extraction times at 3 s and 16 s- from two buzz-pollinated species (Solanum lycopersicum and Solanum elaeagnifolium). RESULTS: Our results show that species, and extraction time significantly influenced pollen extraction, while there were no significant differences for the different vibration frequencies and more importantly, the use of a toothbrush over tuning fork. More pollen was extracted from S. elaeagnifolium when compared to S. lycopersicum, and at longer buzzing time regardless of the instrument used. CONCLUSIONS: Our results suggest that electric toothbrushes can be a viable and inexpensive alternative to tuning forks, and regardless of the instrument used and buzzing frequency, length of buzzing time is also critical in pollen extraction.


Assuntos
Lycopersicon esculentum , Polinização , Animais , Abelhas , Flores , Pólen
2.
Oecologia ; 192(2): 577-590, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31897723

RESUMO

Mutualistic interactions between plants and pollinators play an essential role in the organization and persistence of biodiversity. The structure of interaction networks mediates the resilience of local communities and ecosystem functioning to environmental changes. Hence, network structure conservation may be more critical for maintaining biodiversity and ecological services than the preservation of isolated species in changing landscapes. Here, we intensively surveyed seven 36 km2 landscapes to empirically investigate the effects of forest loss and landscape configuration on the structure of plant-pollinator networks in understory vegetation of Brazilian Atlantic Forest. Our results indicate that forest loss and isolation affect the structure of the plant-pollinator networks, which were smaller in deforested landscapes, and less specialized as patch isolation increased. Lower nestedness and degree of specialization (H'2) indicated that the remaining plant and bee species tend to be generalists, and many of the expected specialized interactions in the network were already lost. Because generalist species generate a cohesive interaction core in these networks, these simplified networks might be resistant to loss of peripheral species, but may be susceptible to the extinction of the most generalist species. We suggest that such a network pattern is an outcome of landscapes with a few remaining isolated patches of natural habitat. Our results add a new perspective to studies of plant-pollinator networks in fragmented landscapes, showing that those interaction networks might also be used to indicate how changes in natural habitat affect biodiversity and biotic interactions.


Assuntos
Ecossistema , Polinização , Animais , Abelhas , Brasil , Florestas , Plantas
3.
Nat Commun ; 11(1): 576, 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-31996690

RESUMO

Urbanisation is an important global driver of biodiversity change, negatively impacting some species groups whilst providing opportunities for others. Yet its impact on ecosystem services is poorly investigated. Here, using a replicated experimental design, we test how Central European cities impact flying insects and the ecosystem service of pollination. City sites have lower insect species richness, particularly of Diptera and Lepidoptera, than neighbouring rural sites. In contrast, Hymenoptera, especially bees, show higher species richness and flower visitation rates in cities, where our experimentally derived measure of pollination is correspondingly higher. As well as revealing facets of biodiversity (e.g. phylogenetic diversity) that correlate well with pollination, we also find that ecotones in insect-friendly green cover surrounding both urban and rural sites boost pollination. Appropriately managed cities could enhance the conservation of Hymenoptera and thereby act as hotspots for pollination services that bees provide to wild flowers and crops grown in urban settings.


Assuntos
Abelhas/fisiologia , Ecologia , Insetos/fisiologia , Polinização , Urbanização , Animais , Abelhas/classificação , Biodiversidade , Cidades , Dípteros , Ecossistema , Flores , Alemanha , Himenópteros , Insetos/classificação , Lepidópteros , Filogenia
4.
Oecologia ; 192(1): 261-272, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31760481

RESUMO

Climate change can negatively impact plant-pollinator interactions, and reduce outcross pollination. For reproductive assurance, an increased capacity for autonomous selfing should benefit the persistence of plants under new temperature conditions. Plastic responses of the autonomous selfing capacity to climate change may occur indirectly due to changes in floral traits associated with this capacity. We tested whether the mixed mating plant Mimulus guttatus is capable of plastic changes in floral traits favoring autonomous selfing in response to temperature changes. In seven growth chambers, we grew M. guttatus originating from a large range of latitudes (from 37.89° N to 49.95° N) and thus home temperatures in North America, and experimentally assessed the (autonomous) selfing and outcrossing capacities of the plants. With an increase in the difference between the overall mean daytime and nighttime experimental test temperature and home temperature, flower length and width decreased. The plastic response in flower size suggests that plants may be more successful at autonomous selfing. However, we did not find direct evidence that M. guttatus responded to increased temperature by an increased autonomous selfing capacity. With an increase in temperature difference, the odds of seed production, number of seeds, and individual seed mass decreased. Our results indicate that global warming and the associated increase in extreme temperature events may be detrimental to the reproduction and thus persistence of some plants.


Assuntos
Mimulus , Flores , América do Norte , Polinização , Reprodução , Temperatura Ambiente
5.
Ecol Lett ; 23(2): 326-335, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31797535

RESUMO

Supporting ecosystem services and conserving biodiversity may be compatible goals, but there is concern that service-focused interventions mostly benefit a few common species. We use a spatially replicated, multiyear experiment in four agricultural settings to test if enhancing habitat adjacent to crops increases wild bee diversity and abundance on and off crops. We found that enhanced field edges harbored more taxonomically and functionally abundant, diverse, and compositionally different bee communities compared to control edges. Enhancements did not increase the abundance or diversity of bees visiting crops, indicating that the supply of pollination services was unchanged following enhancement. We find that actions to promote crop pollination improve multiple dimensions of biodiversity, underscoring their conservation value, but these benefits may not be spilling over to crops. More work is needed to identify the conditions that promote effective co-management of biodiversity and ecosystem services.


Assuntos
Biodiversidade , Ecossistema , Agricultura , Animais , Abelhas , Produtos Agrícolas , Polinização
6.
Ecol Lett ; 23(2): 359-369, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31814265

RESUMO

Within ecological communities, species engage in myriad interaction types, yet empirical examples of hybrid species interaction networks composed of multiple types of interactions are still scarce. A key knowledge gap is understanding how the structure and stability of such hybrid networks are affected by anthropogenic disturbance. Using 15,169 interaction observations, we constructed 16 hybrid herbivore-plant-pollinator networks along an agricultural intensification gradient to explore changes in network structure and robustness to local extinctions. We found that agricultural intensification led to declines in modularity but increases in nestedness and connectance. Notably, network connectance, a structural feature typically thought to increase robustness, caused declines in hybrid network robustness, but the directionality of changes in robustness along the gradient depended on the order of local species extinctions. Our results not only demonstrate the impacts of anthropogenic disturbance on hybrid network structure, but they also provide unexpected insights into the structure-stability relationship of hybrid networks.


Assuntos
Agricultura , Polinização , Biota , Ecossistema , Herbivoria , Plantas
7.
Mol Genet Genomics ; 295(1): 143-154, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31559504

RESUMO

KEY MESSAGE: Floret and seed traits are moderately correlated phenotypically in modern sunflower cultivars, but the underlying genetics are mostly independent. Seed traits in particular are governed in part by epistatic effects among quantitative trait loci. Seed size is an important quality component in marketing commercial sunflower (Helianthus annuus L.), particularly for the in-shell confectionery market, where long and broad seed types are preferred as a directly consumed snack food globally. Floret size is also important because corolla tube length was previously shown to be inversely correlated with pollinator visitation, impacting bee foraging potential and pollinator services to the plant. Commercial sunflower production benefits from pollinator visits, despite being self-compatible, and bees are required in hybrid seed production, where "female" and "male" inbred lines are crossed at field scale. Issues with pollination of long-seed confectionery sunflower suggest that there may be an unfavorable correlation between seed and floret traits; thus, our objective was to determine the strength of the correlation between seed and floret traits, and confirm any co-localization of seed and floret trait loci using genome-wide association analysis in the SAM diversity panel of sunflower. Our results indicate that phenotypic correlations between seed and floret traits are generally low to moderate, regardless of market class, a component of population substructure. Association mapping results mirror the correlations: while a few loci overlap, many loci for the two traits are not overlapping or even adjacent. The genetics of these traits, while modestly quantitative and influenced by epistatic effects, are not a barrier to simultaneous improvement of seed length and pollinator-friendly floret traits. We conclude that breeding for large seed size, which is required for the confectionery seed market, is possible without producing florets too long for efficient use by pollinators, which promotes bee foraging and associated pollination services.


Assuntos
Helianthus/genética , Locos de Características Quantitativas/genética , Sementes/genética , Animais , Abelhas , Cruzamento/métodos , Estudo de Associação Genômica Ampla/métodos , Fenótipo , Polinização/genética
8.
Chemosphere ; 240: 124926, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31726586

RESUMO

Insect pollinators such as bees and syrphid flies play a crucial role in pollinating many food crops, and their diversity and abundance may be influenced by pesticide application patterns. Over three years, we assessed the ecotoxicological impacts on the diversity and abundance of bees and syrphid flies between reduced-risk pesticide programs and standard, conventional pesticide programs in paired plots at six spatially distinct commercial apple orchards. In particular, we quantified pesticide inputs, environmental impact, and community response of bees and syrphids to these pesticide programs. Relative environmental impacts of reduced-risk versus conventional pesticide programs were calculated using Environmental Impact Quotient analysis, while ecological impacts were characterized by assessing the abundance, richness, and species assemblages of bees and syrphids. Adopting a reduced-risk pesticide program for apple pest management reduced the use (in terms of kg a.i./ha) of organophosphate and pyrethroid insecticides by approximately 97.6% and 100% respectively, but increased the use of neonicotinoid pesticides (acetamiprid, imidacloprid, thiacloprid) by 40.4% compared to the orchards under standard conventional pesticide program. Regardless of pesticide inputs, abundance, richness and species assemblages of bees and syrphids did not differ between reduced-risk and conventional pest management programs. However, the environmental impact of pesticide inputs was reduced by 89.8% in reduced-risk pesticide program. These findings suggest that the implementation of reduced-risk pesticide program may reduce pesticide environmental impact, in addition to being safer to farm workers, without adversely affecting the robust community composition of bees and syrphids in commercial apple orchards in the mid-Atlantic region.


Assuntos
Produtos Agrícolas , Malus , Controle de Pragas/métodos , Praguicidas , Polinização , Animais , Abelhas , Ecotoxicologia , Meio Ambiente , Insetos , Inseticidas , Neonicotinoides , Nitrocompostos , Piretrinas , Tiazinas
9.
Ecol Lett ; 23(1): 129-139, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31650660

RESUMO

Pollination is thought to be under positive density-dependence, destabilising plant coexistence by conferring fitness disadvantages to rare species. Such disadvantage is exacerbated by interspecific competition but can be mitigated by facilitation and intraspecific competition. However, pollinator scarcity should enhance intraspecific plant competition and impose disadvantage on common over rare species (negative density-dependence, NDD). We assessed pollination proxies (visitation rate, pollen receipt, pollen tubes) in a generalised plant community and related them to conspecific and heterospecific density, expecting NDD and interspecific facilitation due to the natural pollinator scarcity. Contrary to usual expectations, all proxies indicated strong intraspecific competition for common plants. Moreover interspecific facilitation prevailed and was stronger for rare than for common plants. Both NDD and interspecific facilitation were modulated by specialisation, floral display and pollinator group. The combination of intraspecific competition and interspecific facilitation fosters plant coexistence, suggesting that pollination can be a niche axis maintaining plant diversity.


Assuntos
Ecossistema , Polinização , Flores , Plantas , Pólen
10.
Oecologia ; 192(2): 489-499, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31844986

RESUMO

High-severity wildfires, which can homogenize floral communities, are becoming more common relative to historic mixed-severity fire regimes in the Northern Rockies of the U.S. High-severity wildfire could negatively affect bumble bees, which are typically diet generalists, if floral species of inadequate pollen quality dominate the landscape post-burn. High-severity wildfires often require more time to return to pre-burn vegetation composition, and thus, effects of high-severity burns may persist past initial impacts. We investigated how wildfire severity (mixed- vs. high-severity) and time-since-burn affected available floral pollen quality, corbicular pollen quality, and bumble bee nutrition using percent nitrogen as a proxy for pollen quality and bumble bee nutrition. We found that community-weighted mean floral pollen nitrogen, corbicular pollen nitrogen, and bumble bee nitrogen were greater on average by 0.82%N, 0.60%N, and 1.16%N, respectively, in mixed-severity burns. This pattern of enhanced floral pollen nitrogen in mixed-severity burns was likely driven by the floral community, as community-weighted mean floral pollen percent nitrogen explained 87.4% of deviance in floral community composition. Only bee percent nitrogen varied with time-since-burn, increasing by 0.33%N per year. If these patterns persist across systems, our findings suggest that although wildfire is an essential ecosystem process, there are negative early successional impacts of high-severity wildfires on bumble bees and potentially on other pollen-dependent organisms via reductions in available pollen quality and nutrition. This work examines a previously unexplored pathway for how disturbances can influence native bee success via altering the nutritional landscape of pollen.


Assuntos
Incêndios Florestais , Animais , Abelhas , Dieta , Ecossistema , Estado Nutricional , Pólen , Polinização
11.
Plant Mol Biol ; 102(3): 287-306, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31872308

RESUMO

KEY MESSAGE: At the early stage of pollination, the difference in gene expression between compatibility and incompatibility is highly significant about the pollen-specific expression of the LRR gene, resistance, and defensin genes. In Rosaceae, incompatible pollen can penetrate into the style during the gametophytic self-incompatibility response. It is therefore considered a stylar event rather than a stigmatic event. In this study, we explored the differences in gene expression between compatibility and incompatibility in the early stage of pollination. The self-compatible pear variety "Jinzhuili" is a naturally occurring bud mutant from "Yali", a leading Chinese native cultivar exhibiting typical gametophytic self-incompatibility. We collected the styles of 'Yali' and 'Jinzhuili' at 0.5 and 2 h after self-pollination and then performed high-throughput sequencing. According to the KEGG analysis of the differentially expressed genes, several metabolic pathways, such as "Plant hormone signal transduction", "Plant-pathogen interaction", are the main pathways was the most represented pathway. Quantitative PCR was used to validate these differential genes. The expression levels of genes related to pollen growth and disease inhibition, such as LRR (Leucine-rich repeat extensin), resistance, defensin, and auxin, differed significantly between compatible and incompatible pollination. Interestingly, at 0.5 h, most of these genes were upregulated in the compatible pollination system compared with the incompatible pollination system. Calcium transport, which requires ATPase, also demonstrated upregulated expression. In summary, the self-incompatibility reaction was initiated when the pollen land on the stigma.


Assuntos
Pólen/genética , Polinização/genética , Polinização/fisiologia , Pyrus/genética , Pyrus/fisiologia , /métodos , Morte Celular , Técnicas de Reprogramação Celular , Regulação da Expressão Gênica de Plantas/fisiologia , Genes de Plantas/genética , Ácidos Indolacéticos , Oxigenases/genética , Reguladores de Crescimento de Planta , Proteínas de Plantas/genética , Pólen/crescimento & desenvolvimento
12.
Insect Sci ; 27(1): 133-142, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29740981

RESUMO

Over 50 genera of bees release pollen from flower anthers using thoracic vibrations, a phenomenon known as buzz-pollination. The efficiency of this process is directly affected by the mechanical properties of the buzzes, namely the duration, amplitude, and frequency. Nonetheless, although the effects of the former two properties are well described, the role of buzz frequency on pollen release remains unclear. Furthermore, nearly all of the existing studies describing vibrational properties of natural buzz-pollination are limited to bumblebees (Bombus) and carpenter bees (Xylocopa) constraining our current understanding of this behavior and its evolution. Therefore, we attempted to minimize this shortcoming by testing whether flower anthers exhibit optimal frequency for pollen release and whether bees tune their buzzes to match these (optimal) frequencies. If true, certain frequencies will trigger more pollen release and lighter bees will reach buzz frequencies closer to this optimum to compensate their smaller buzz amplitudes. Two strategies were used to test these hypotheses: (i) the use of (artificial) vibrational playbacks in a broad range of buzz frequencies and amplitudes to assess pollen release by tomato plants (Solanum lycopersicum L.) and (ii) the recording of natural buzzes of Neotropical bees visiting tomato plants during pollination. The playback experiment indicates that although buzz frequency does affect pollen release, no optimal frequency exists for that. In addition, the recorded results of natural buzz-pollination reveal that buzz frequencies vary with bee genera and are not correlated with body size. Therefore, neither bees nor plants are tuned to optimal pollen release frequencies. Bee frequency of buzz-pollination is a likely consequence of the insect flight machinery adapted to reach higher accelerations, while flower plant response to buzz-pollination is the likely result of its pollen granular properties.


Assuntos
Abelhas/fisiologia , Lycopersicon esculentum/fisiologia , Polinização , Animais , Brasil , Pólen , Especificidade da Espécie , Vibração
13.
Oecologia ; 191(4): 873-886, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31676969

RESUMO

An animal's diet contributes to its survival and reproduction. Variation in diet can alter the structure of community-level consumer-resource networks, with implications for ecological function. However, much remains unknown about the underlying drivers of diet breadth. Here we use a network approach to understand how consumer diet changes in response to local and landscape context and how these patterns compare between closely-related consumer species. We conducted field surveys to build 36 quantitative plant-pollinator networks using observation-based and pollen-based records of visitation across the gulf-coast cotton growing region of Texas, US. We focused on two key cotton pollinator species in the region: the social European honey bee, Apis mellifera, and the solitary native long-horned bee, Melissodes tepaneca. We demonstrate that diet breadth is highly context-dependent. Specifically, local factors better explain patterns of diet than regional factors for both species, but A. mellifera and M. tepaneca respond to local factors with contrasting patterns. Despite being collected directly from cotton blooms, both species exhibit significant preferences for non-cotton pollen, indicating a propensity to spend substantial effort foraging on remnant vegetation despite the rarity of these patches in the intensely managed cotton agroecosystem. Overall, our results demonstrate that diet is highly context- and species-dependent and thus an understanding of both factors is key for evaluating the conservation of important cotton pollinators.


Assuntos
Pólen , Polinização , Animais , Abelhas , Dieta , Plantas , Texas
14.
J Agric Food Chem ; 67(48): 13221-13227, 2019 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-31682121

RESUMO

Apple flowers of most varieties require pollinator-mediated cross-pollination. However, little is known about the cues used by pollinators to find the flowers. We used bioassays to investigate the importance of visual and olfactory cues for the attraction of honeybee pollinators to apple flowers. Chemical-analytical and electrophysiological approaches were used to determine floral scents and investigate antennal responses of honeybees to scents from flowering twigs. Bioassays showed that visual and olfactory cues were equally important for the attraction of honeybees to apple flowers. Floral scents were dominated by aromatic components, mainly benzyl alcohol, and the antennae of honeybees responded to a large number of components, among them to benzyl alcohol, linalool, and indole. Our study aims to better understand how this important fruit crop communicates with its main pollinators. This knowledge might be used to improve the attractiveness of apple flowers to pollinators to optimize fruit sets.


Assuntos
Abelhas/fisiologia , Malus/química , Compostos Orgânicos Voláteis/química , Animais , Flores/química , Flores/parasitologia , Cromatografia Gasosa-Espectrometria de Massas , Malus/parasitologia , Odorantes/análise , Polinização , Olfato
15.
Nat Ecol Evol ; 3(11): 1521-1524, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31666734

RESUMO

Recent research has shown that several managed bee species have specific P450 enzymes that are preadapted to confer intrinsic tolerance to some insecticides including certain neonicotinoids. However, the universality of this finding across managed bee pollinators is unclear. Here we show that the alfalfa leafcutter bee, Megachile rotundata, lacks such P450 enzymes and is >2,500-fold more sensitive to the neonicotinoid thiacloprid and 170-fold more sensitive to the butenolide insecticide flupyradifurone than other managed bee pollinators. These findings have important implications for the safe use of insecticides in crops where M. rotundata is used for pollination, and ensuring that regulatory pesticide risk assessment frameworks are protective of this species.


Assuntos
Inseticidas , 4-Butirolactona/análogos & derivados , Animais , Abelhas , Neonicotinoides , Polinização
16.
Oecologia ; 191(4): 887-896, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31686227

RESUMO

Herbivore attack can alter plant interactions with pollinators, ranging from reduced to enhanced pollinator visitation. The direction and strength of effects of herbivory on pollinator visitation could be contingent on the type of plant tissue or organ attacked by herbivores, but this has seldom been tested experimentally. We investigated the effect of variation in feeding site of herbivorous insects on the visitation by insect pollinators on flowering Brassica nigra plants. We placed herbivores on either leaves or flowers, and recorded the responses of two pollinator species when visiting flowers. Our results show that variation in herbivore feeding site has profound impact on the outcome of herbivore-pollinator interactions. Herbivores feeding on flowers had consistent positive effects on pollinator visitation, whereas herbivores feeding on leaves did not. Herbivores themselves preferred to feed on flowers, and mostly performed best on flowers. We conclude that herbivore feeding site choice can profoundly affect herbivore-pollinator interactions and feeding site thereby makes for an important herbivore trait that can determine the linkage between antagonistic and mutualistic networks.


Assuntos
Herbivoria , Polinização , Animais , Flores , Insetos , Folhas de Planta
17.
J Chem Ecol ; 45(10): 869-878, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31741191

RESUMO

Most plant species depend upon insect pollination services, including many cash and subsistence crops. Plants compete to attract those insects using visual cues and floral odor which pollinators associate with a reward. The cacao tree, Theobroma cacao, has a highly specialized floral morphology permitting pollination primarily by Ceratopogonid midges. However, these insects do not depend upon cacao flowers for their life cycle, and can use other sugar sources. To understand how floral cues mediate pollination in cacao we developed a method for rearing Ceratopogonidae through several complete lifecycles to provide material for bioassays. We carried out collection and analysis of cacao floral volatiles, and identified a bouquet made up exclusively of saturated and unsaturated, straight-chain hydrocarbons, which is unusual among floral odors. The most abundant components were tridecane, pentadecane, (Z)-7-pentadecene and (Z)-8-heptadecene with a heptadecadiene and heptadecatriene as minor components. We presented adult midges, Forcipomyia sp. (subgen. Forcipomyia), Culicoides paraensis and Dasyhelea borgmeieri, with natural and synthetic cacao flower odors in choice assays. Midges showed weak attraction to the complete natural floral odor in the assay, with no significant evidence of interspecific differences. This suggests that cacao floral volatiles play a role in pollinator behavior. Midges were not attracted to a synthetic blend of the above four major components of cacao flower odor, indicating that a more complete blend is required for attraction. Our findings indicate that cacao pollination is likely facilitated by the volatile blend released by flowers, and that the system involves a generalized odor response common to different species of Ceratopogonidae.


Assuntos
Cacau/química , Ceratopogonidae/fisiologia , Compostos Orgânicos Voláteis/química , Animais , Cacau/metabolismo , Ceratopogonidae/efeitos dos fármacos , Flores/química , Flores/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Pólen/química , Pólen/metabolismo , Polinização/efeitos dos fármacos , Olfato , Compostos Orgânicos Voláteis/farmacologia
18.
Nat Commun ; 10(1): 4802, 2019 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-31641114

RESUMO

Microbes can establish mutualistic interactions with plants and insects. Here we track the movement of an endophytic strain of Streptomyces bacteria throughout a managed strawberry ecosystem. We show that a Streptomyces isolate found in the rhizosphere and on flowers protects both the plant and pollinating honeybees from pathogens (phytopathogenic fungus Botrytis cinerea and pathogenic bacteria, respectively). The pollinators can transfer the Streptomyces bacteria among flowers and plants, and Streptomyces can move into the plant vascular bundle from the flowers and from the rhizosphere. Our results present a tripartite mutualism between Streptomyces, plant and pollinator partners.


Assuntos
Abelhas/fisiologia , Fragaria/fisiologia , Streptomyces/fisiologia , Animais , Botrytis/patogenicidade , Flores , Fragaria/microbiologia , Doenças das Plantas/microbiologia , Pólen , Polinização , RNA Ribossômico 16S , República da Coreia , Esporos Fúngicos , Streptomyces/genética , Simbiose
19.
Environ Entomol ; 48(6): 1249-1259, 2019 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-31603491

RESUMO

Bumble bees provide valuable pollination services to many wild and agricultural plants. Populations of some bumble bee species are in decline, prompting the need to better understand bumble bee biology and to develop methodologies for assessing the effects of environmental stressors on these bees. Use of bumble bee microcolonies as an experimental tool is steadily increasing. This review closely examines the microcolony model using peer-reviewed published literature identified by searching three databases through November 2018. Microcolonies have been successfully used for investigating a range of endpoints including behavior, the gut microbiome, nutrition, development, pathogens, chemical biology, and pesticides/xenobiotics. Methods for the initiation and monitoring of microcolonies, as well as the recorded variables were catalogued and described. From this information, we identified a series of recommendations for standardizing core elements of microcolony studies. Standardization is critical to establishing the foundation needed to support use of this model for biological response investigations and particularly for supporting use in pesticide risk assessment.


Assuntos
Himenópteros , Praguicidas , Agricultura , Animais , Abelhas , Polinização , Medição de Risco
20.
Ecol Lett ; 22(12): 2103-2110, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31621156

RESUMO

Bees are ecosystem service providers that are globally threatened by losses of plant diversity. However, effects of multi-species floral displays on bees in agro-ecosystems with variable landscape context remain poorly understood, hindering pollinator conservation tactics. We addressed this knowledge gap through a novel application of the modified Price equation to evaluate responses of bees to diverse floral communities on 36 farms in Washington, USA, over 3 years. We found that floral richness, not floral identity, was the best predictor of floral visits by bees. However, the benefits of regionally rare floral species (i.e. plants found at relatively few sites) were only fully realised when farms were embedded in diverse landscapes. Our analysis used the modified Price equation to demonstrate that plant diversity, rather than specific plant species, promotes pollinator visitation, and that diverse landscapes promote the response of pollinators to regionally rare plant species.


Assuntos
Ecossistema , Polinização , Animais , Abelhas , Flores
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