Littérature scientifique sur le sujet « Floral resource sharing »

The purpose of this study was to investigate the reproductive phenology and sharing of floral resource (nectar) of Dahlstedtia pinnata (Benth.) Malme. (Fabaceae), endemic of Atlantic forest, among hummingbirds. For the phenology, we looked at the presence of reproductive structures in the plants, and for floral resource sharing, the frequency of potential pollinators and foraging behaviors were examined. This study was conducted in Pedra Branca State Park, in state of Rio de Janeiro, in a dense ombrophilous forest, between August 2010 and August 2011. Flowering occurred between December 2010 and March 2011, and fruiting between April and June 2011. Hummingbirds' foraging schedules differed significantly, with legitimate visits to the flowers occurring in the morning and illegitimate visits occurring during late morning and the afternoon. Five species visited flowers, three of which were legitimate visitors: Phaethornis ruber, P. pretrei, and Ramphodon naevius. Amazilia fimbriata and Thalurania glaucopis females only visited illegitimately. Phaethornis ruber robbed nectar (78% of illegitimate visits, n=337). Ramphodon naevius, with a territorial foraging behavior and a body size bigger than that of other observed hummingbird species, dominated the floral visits, which suggests that D. pinnata is an important nourishing resource for this endemic bird of the Atlantic forest, currently globally categorized as Near Threatened.

Viruses are known to contribute to bee population decline. Possible spillover is suspected from the co-occurrence of viruses in wild bees and honey bees. In order to study the risk of virus transmission between wild and managed bee species sharing the same floral resource, we tried to maximize the possible cross-infections using Phacelia tanacetifolia, which is highly attractive to honey bees and a broad range of wild bee species. Virus prevalence was compared over two years in Southern France. A total of 1137 wild bees from 29 wild bee species (based on COI barcoding) and 920 honey bees (Apis mellifera) were checked for the seven most common honey bee RNA viruses. Halictid bees were the most abundant. Co-infections were frequent, and Sacbrood virus (SBV), Black queen cell virus (BQCV), Acute bee paralysis virus (ABPV) and Israeli acute paralysis virus (IAPV) were widespread in the hymenopteran pollinator community. Conversely, Deformed wing virus (DWV) was detected at low levels in wild bees, whereas it was highly prevalent in honey bees (78.3% of the samples). Both wild bee and honey bee virus isolates were sequenced to look for possible host-specificity or geographical structuring. ABPV phylogeny suggested a specific cluster for Eucera bees, while isolates of DWV from bumble bees (Bombus spp.) clustered together with honey bee isolates, suggesting a possible spillover.

Background and aims – The manner by which the effects of multiple antagonists combine is a fundamental issue in ecology. This issue has been especially important in plant-herbivore evolutionary ecology—particularly predicting whether the combined fitness impacts of multiple herbivores on a shared host plant can be inferred by simply adding the individual impacts that each herbivore has when feeding alone. Despite accumulating empirical data, relatively little theoretical progress has been made in explaining why impacts of herbivore damage often combine nonadditively, as well as predicting the conditions that lead to a greater-than-additive (synergistic) or to a less-than-additive (subadditive) pattern. Material and methods – Based on considerations of limiting resources and source-sink relationships, I proposed and tested two hypotheses: 1) The fitness impacts of two species of herbivores that affect the same resource (i.e. feed on the same tissue in a similar fashion) will combine in a synergistic pattern (if that resource is not limiting reproduction when plants do not experience herbivory), and 2) The fitness impacts of two herbivores that affect different resources (i.e. feed on different tissues) will combine in a subadditive pattern. I performed a field experiment in which horsenettle (Solanum carolinense) was exposed to a factorial combination of four levels of leaf herbivory and five levels of simulated floral herbivory. Key results – The results were consistent with both hypotheses: 1) The combined fitness impact of flower damage that was simulated as being caused by two florivorous species feeding on the same plants was greater than the sum of the same total amount of damage when the two species were simulated as feeding individually; and 2) The combined fitness impact of the leaf and floral damage was less than the sum of the same total amount of damage when the two species fed individually. Conclusions – The main ecoevolutionary implication of these results is that subadditive impacts of leaf- and flower-feeding herbivores could weaken selection for resistance in horsenettle (or any plant species that hosts multiple herbivores), and thus subadditive impacts may contribute to the maintenance of diverse herbivore communities sharing a species of host plant.

Substantial genetic and physiological efforts were made to understand the causal factors of floral abortion and grain filling problem in wheat. However, the vascular architecture during wheat spikelet development is surprisingly under-researched. We used the branched headt near-isogenic lines, FL-bht-A1-NILs, to visualise the dynamics of spikelet fertility and dry matter accumulation in spikelets sharing the same rachis node (henceforth Primary Spikelet, PSt, and Secondary Spikelet, SSt). The experiment was conducted after grouping FL-bht-A1-NILs into two groups, where tillers were consistently removed from one group. Our results show differential spikelet fertility and dry matter accumulation between the PSt and SSt, but also showed a concomitant improvement after de-tillering. This suggests a tight regulation of assimilate supply and dry matter accumulation in wheat spikelets. Since PSt and SSt share the same rachis node, the main vascular bundle in the rachis/rachilla is expected to bifurcate to connect each spikelet/floret to the vascular system. We postulate that the vascular structure in the wheat spikelet might even follow Murray’s law, where the wide conduits assigned at the base of the spikelet feed the narrower conduits of the distal florets. We discuss our results based on the two modalities of the vascular network systems in plants.

Regional floras are primary resources for plant identification, an essential step in developing conservation strategies. They also provide students with a scientific window on the plants around them and help them learn botanical terminology, but they are expensive to maintain and publish. We are developing web-accessible updates for different floras, as part of which we are using online resources to help us work more effectively while rapidly providing richer resources. We use Key Base for sharing dichotomous keys, linking the terminal taxa to subsidiary keys or descriptive taxon pages. Taxon pages are generated in OpenHerbarium which enables integrating specimen and observation data with descriptions, line drawings, and images and displaying maps based on georeferenced specimen data. Its nomenclatural backbone is easily modified to reflect new treatment and can also handle multiple taxonomies. We are examining is the possibility of using a Wikipedia approach to provide a glossary.

SUMMARYThe equitable sharing of benefits from natural resources is a key target of the Convention on Biological Diversity. Trade in its native species is one way in which a country can potentially benefit from its natural resources, and even small-scale traders can now access global markets online. However, little is known about the extent of benefit sharing for many products, and the extent to which the appropriate processes and permits are being used. We surveyed online trade in a lucrative and widely sold product in Southeast Asia (horticultural orchids) to assess the extent of access and benefit sharing. In total, 20.8% (n = 1120) of orchid species from the region were being sold. Although seven out of ten countries were trading, five had very little or no trade in their native species, and the majority of recently described endemic species being traded from non-range states had no reported Convention on the International Trade in Endangered Species of Wild Fauna and Flora exports from their country of origin. We suggest that addressing access and benefit-sharing gaps requires wider recognition of the problem, coupled with capacity building in the countries currently benefitting least: Laos, Myanmar and Cambodia. The priority should be to increase botanical capacity and enable these countries to better control the commercialization and trade of their native species.

North American horticulture cultivates an astonishing diversity of ornamental species, from nearly every floristic region, but its landscapes are dominated by temperate species drawn from eastern Asia. The East Asiatic floristic region is one of the most diverse in the world with a high level of endemism across taxonomic ranks and ancient relicts of a once widespread flora. From this, a large number of ornamental genera and species have been introduced, from either a long history of cultivation in Asia or directly from the wild, where they have since become fixtures in European and American gardens. The success of Asian germplasm in American horticulture is attributable, in part, to a shared evolutionary history, climate matching, and pre-adaptability. Continuing access to these genetic resources is now governed by national legislation and influenced by an evolving international regime of access and benefit-sharing influenced by the Convention on Biological Diversity. Furthermore, updated plant quarantine regulations have added additional requirements for the importation of foreign plant genetic resources. The newly created category within the USDA Animal and Plant Health Inspection Service (APHIS) Q37 regulations known as “not authorized pending pest risk analysis” (NAPPRA) restricts the import of plants for planting that may harbor pests or become pests that are not already established within the United States. To this end, scientists involved in the collection or use of Asian plant genetic resources are affected by recent changes in international and national laws, regulations, and access and benefit-sharing regimes.

AbstractWe studied the songs of Wedge-tailed Sabrewings (Campylopterus curvipennis) in six localities from central Veracruz, Mexico, to document structure and variation within and between singing groups in the same geographic region. Wedgetailed Sabrewing songs were acoustically, structurally, and behaviorally complex, rivaling those of other taxa with complex signals. Songs of individual birds were composed of >45 well-differentiated and structurally complex syllables. We found 239 different syllable types across eight recorded singing groups of Wedge-tailed Sabrewings (∼20 syllable types per singing group), with the greatest versatility recorded in hummingbirds to date. The acoustic variation (15 variables) was summarized in three principal components (58% of acoustic variation), in which intragroup variability accounted for most of the observed variation. We found significant differences between and within groups in terms of syllable sharing (Jaccard’s similarity coefficient). Individuals generally shared >50% of syllable types within groups, whereas syllable sharing was <10% between individuals from different groups. The same microgeographic pattern was supported in a UPGMA (unweighted pair-group method with arithmetic mean) analysis where individual songs from each singing group clustered separately. However, songs recorded at the same location differed between seasons, which suggests that this species does not exhibit geographically distinct dialects that are consistent across time. The interplay among this species’ social system, distribution of its floral resources, and microgeographic and temporal variation of its song requires further research.

As land-use patterns change over time, some pollinating insects continue to decline both in abundance and diversity. This is due, in part, to reductions in floral resources that provide sufficient nectar and pollen. Our overall goal is to help increase the use of plants that enhance pollinator health by providing research-based information that is easily accessible to the public. To assess the most successful mode of sharing this information, a survey was distributed to more than 4000 Master Gardener (MG) volunteers of Florida. The objectives of our survey were to gauge both knowledge and interest in common pollinators, common pollinator-friendly floral resources, and a favored means of accessing material about additional pollinator-friendly plants for landscape use. With a response rate of just over 18%, results showed that there is a clear interest among Florida MGs in learning more about pollinators and pollinator-friendly plants with face-to-face classes followed by a website as the preferred modes of accessing educational materials on this topic. Respondents on average were extremely interested in learning more about pollinator plants [mean of 4.41 out of 5.0 (sd = 0.89)], with greatest interest in butterflies/moths (Lepidoptera), followed by bees (Hymenoptera), birds (Aves), bats (Chiroptera), and beetles (Coleoptera). Overall, MG participants felt more confident (P < 0.0001) in their knowledge of pollinator-friendly plants (mean 3.24 out of 5.0) than pollinator insects (mean 3.01 out of 5.0). When tested, 88.5% were able to correctly identify black-eyed susan (Rudbeckia hirta), with 70.1% correctly identifying spotted beebalm (Monarda punctata). Variations were observed in tested knowledge of pollinating insects, with 90.2% correctly identifying a zebra longwing (Heliconius charithonia) and only 32.6% correctly identifying a striped-sweat bee (Agapostemon splendens). These results revealed that MGs perceived themselves to be fairly knowledgeable about both pollinator plants and pollinating insects, yet their tested knowledge ranged widely depending on the actual plant and pollinator type. This suggests an emphasis be given for future MG training focused on diverse plant and pollinator species, preferably in a face-to-face environment. Results also show that additional resources regarding pollinator-friendly plants, as well as identification material on pollinating insects, are both desired and valued by our Florida MG community.

Conserver les espèces pollinisatrices est un enjeu majeur, notamment en milieu agricole où elles sont indispensables à la pollinisation de différentes cultures. Ici, nous avons décidé de caractériser ces espèces et leurs ressources florales dans une plaine céréalière intensive, à travers l’utilisation de plusieurs années de données acquises grâce à plusieurs protocoles d’échantillonnage. Cette plaine se caractérise par une forte dynamique spatio-temporelle, résultant des floraisons massives mais brèves des cultures oléagineuses. Nous avons recensé sur cette plaine près d’un tiers des espèces d’abeilles trouvées en France, dont certaines sont rares, et avons cherché à mieux comprendre leur écologie afin d’aider au maintien de cette diversité. Les abeilles co-occurrent avec d’autres pollinisateurs (papillons, syrphes) qui sont pour certains peu étudiés dans la littérature : une analyse de la niche alimentaire de l’ensemble de ces pollinisateurs a permis de mieux comprendre leur partage des ressources. La floraison du tournesol, contrairement à celle du colza, conduit à un faible recouvrement de niche entre pollinisateurs mais crée des réseaux d’interaction peu équilibrés où la quasi-totalité des liens de la fleur de culture s’établissent avec une seule espèce pollinisatrice, l’abeille domestique. À l’inverse, lors de la floraison du colza, l’abeille domestique et la fleur de colza possèdent chacune de nombreux partenaires d’interaction et sont des espèces clés maintenant une forte stabilité du réseau. Établir une dichotomie entre ces cultures à floraison massive – trop souvent considérées de manière monolithique – semble judicieux pour les recherches futures
The conservation of pollinators is a major issue, especially in farmlands where they are essential for pollinating different crops. Here, we have decided to characterize these species and their floral resources in an intensive agricultural plain, using several years of data acquired thanks to several sampling protocols. This plain is characterized by a strong spatio-temporal dynamic, resulting from the massive but brief flowering of oleaginous plants crops. In this study site, we have sampled nearly a third of the bee species already found in France, some of them being rare, and have sought to better understand their ecology in order to help to maintain this species diversity. Bees co-occur with other pollinators (butterflies, hoverflies), among which some are little studied in previous literature: an analysis of the food habits of all of these pollinators has enabled to better understand their sharing of floral resources. The sunflower flowering, unlike that of oilseed rape, leads to a low niche overlap between pollinators but creates unbalanced interaction networks where almost all the links of the crop flower are established with a single pollinator species, the honeybee. Conversely, during oilseed rape flowering, the honeybee and the oilseed rape flower each have many interaction partners and are key species, maintaining a strong network stability. Introduce a dichotomy between these both mass-flowering crops – too often considered as monolithic – seems a wise advice for future research

Abstract The long sequence of lake-shore occupations of the Acheulian site of Gesher Benot Ya‛aqov (MIS 18–20) includes extremely rich sequential archaeological horizons spanning ca. 50 Ka and dated to 0.79 Mya. During the last three decades the behavior of the Gesher Benot Ya‛aqov (GBY) Acheulian hominins was investigated through a plethora of multidisciplinary archaeological studies. These repeatedly revealed aspects associated with behavioral modernity, indicated by systematic butchering, elaborated plant processing, advanced lithic expertise, hafting, and spatial organization. Through a synthesis of previous studies, this chapter formulates an overall cognitive framework for Acheulian behavior at the site, attempting to identify the cognitive traits that enabled this behavior. To do so, the chapter draws parallels between cognitive traits, well defined by cognitive science, and diverse activities inferred from archaeological finds at GBY. These parallels suggest that the Acheulian hominins of GBY carried out tasks that necessitated a chain of steps, performed at different times in different places, requiring them to arrange their memories in sequential time (i.e., sequential memory). Hominins were able to acknowledge a variety of lithic, faunal, and floral resources, even when these were not physically present (i.e., displaced reference). The acquisition and transportation of resources for later manipulation and sharing required delayed gratification (i.e., inhibition). In addition, the chapter suggests that the accumulated knowledge of the GBY hominins was acquired through their ability to operate (“move” subjectively and fluidly) between past and future events (i.e., autonoesis). The integration and contemporaneity of these characteristics suggest that cognitive traits associated with modern cognition were already possessed by Acheulian hominins as early as early Middle Pleistocene.

Floral and faunal diversity represents the health of an ecosystem. Increase in the number of endangered plants acts as an alarming sign of ecosystem’s imbalance. The ecological failure pose threat to our own health, thus by saving endangered species our own health is being saved. Government, non-profit international organizations, local communities and individuals are working together to protect and restore population levels. Biological Diversity Act (2002) for conservation of biodiversity is a landmark effort by Indian government as it provides mechanisms for knowledge, sustainable use of components of biological diversity and fair and equitable sharing of the benefits arising out of the use of biological resources. The various awareness campaigns have been conducted for local communities with regard to the conservation of endangered species. Both in-situ (on site) and ex-situ (off site) conservation strategies target critical habitats under continuous threat of extinction. Conservation programmes that centred mainly on the local masses which completely depend upon the environment including forests, lakes and wildlife for their needs truly showcase the leadership of local and indigenous communities in protecting biodiversity. The rights of local communities in decision making must be recognized and supported through clear laws and regulations. Sacred groves, a legacy of prehistoric traditions of nature conservation act as an ideal centre for biodiversity conservation. Besides providing vital ecosystem services to people, these are of immense ecological significance. Community conservation is the need of the hour in terms of conserving biodiversity at ground level.