Bee microbiomes in a changing climate: Investigating the effects of temperature on solitary bee life history and health.

Climate change is rapidly warming thermal environments, an important abiotic stimulus governing interactions between microbial symbionts and their hosts. Increasing evidence suggests that solitary bees rely on pollen provision microbes for successful development. However, the effects of heat stress on provision microbiota and the resulting consequences for larval health and development remain to be examined.

Organic orchard floor management in peach: effects on arthropods and associated fruit injury in the Intermountain West.

Understanding orchard floor management is critical to organic tree-fruit production systems given its impact on weeds, soil fertility, tree health, and crop yield. Several viable options are available to producers for weed management and promotion of organic fertility, including use of turf and broadleaf alleyway covers and living and nonliving tree-row mulches. While these measures can be effective, little is known about how these strategies influence arthropod pests, which cause fruit injury.

The Floral Microbiome and Its Management in Agroecosystems: A Perspective.

Disease management is critical to ensuring healthy crop yields and is often targeted at flowers because of their susceptibility to pathogens and direct link to reproduction. Many disease management strategies are unsustainable however because of the potential for pathogens to evolve resistance, or nontarget effects on beneficial insects. Manipulating the floral microbiome holds some promise as a sustainable alternative to chemical means of disease control.

Potential effects of nectar microbes on pollinator health.

Floral nectar is prone to colonization by nectar-adapted yeasts and bacteria via air-, rain-, and animal-mediated dispersal. Upon colonization, microbes can modify nectar chemical constituents that are plant-provisioned or impart their own through secretion of metabolic by-products or antibiotics into the nectar environment. Such modifications can have consequences for pollinator perception of nectar quality, as microbial metabolism can leave a distinct imprint on olfactory and gustatory cues that inform foraging decisions.

Documenting pollinators, floral hosts, and plant-pollinator interactions in U.S. Pacific Northwest agroecosystems.

The abundance and diversity of pollinator populations are in global decline. Managed pollinator species, like honey bees, and wild species are key ecosystem service providers in both natural and managed agroecosystems. However, relatively few studies have exhaustively characterized pollinator populations in diverse agroecosystems over multiple years, while also thoroughly documenting plant-pollinator interactions.

Floral Microbes Suppress Growth of with Minimal Effects on Honey Bee Feeding.

Management of , the causal agent of brown rot blossom blight in almond (), relies heavily on the use of chemical fungicides during bloom. However, chemical fungicides can have nontarget effects on beneficial arthropods, including pollinators, and select for resistance in the pathogen of concern. Almond yield is heavily reliant on successful pollination by healthy honey bees (); thus, identifying sustainable, effective, and pollinator-friendly control methods for blossom blight during bloom is desirable.

Orchard Management and Landscape Context Mediate the Pear Floral Microbiome.

Crop-associated microbiota are a key factor affecting host health and productivity. Most crops are grown within heterogeneous landscapes, and interactions between management practices and landscape context often affect plant and animal biodiversity in agroecosystems. However, whether these same factors typically affect crop-associated microbiota is less clear.

Generalising indirect defence and resistance of plants.

Indirect defence, the adaptive top-down control of herbivores by plant traits that enhance predation, is a central component of plant-herbivore interactions. However, the scope of interactions that comprise indirect defence and associated ecological and evolutionary processes has not been clearly defined. We argue that the range of plant traits that mediate indirect defence is much greater than previously thought, and we further organise major concepts surrounding their ecological functioning.

Microbial Co-Occurrence in Floral Nectar Affects Metabolites and Attractiveness to a Generalist Pollinator.

Microbial metabolism can shape cues important for animal attraction in service-resource mutualisms. Resources are frequently colonized by microbial communities, but experimental assessment of animal-microbial interactions often focus on microbial monocultures. Such an approach likely fails to predict effects of microbial assemblages, as microbe-microbe interactions may affect in a non-additive manner microbial metabolism and resulting chemosensory cues.

Microbial metabolites elicit distinct olfactory and gustatory preferences in bumblebees.

Animals such as bumblebees use chemosensory cues to both locate and evaluate essential resources. Increasingly, it is recognized that microbes can alter the quality of foraged resources and produce metabolites that may act as foraging cues. The distinct nature of these chemosensory cues however and their use in animal foraging remain poorly understood.

Bacteria and Competing Herbivores Weaken Top-Down and Bottom-Up Aphid Suppression.

Herbivore suppression is mediated by both plant defenses and predators. In turn, plant defenses are impacted by soil fertility and interactions with soil bacteria. Measuring the relative importance of nutritional and microbial drivers of herbivore resistance has proven problematic, in part because it is difficult to manipulate soil-bacterial community composition.

Chronic impacts of invasive herbivores on a foundational forest species: a whole-tree perspective.

Forests make up a large portion of terrestrial plant biomass, and the long-lived woody plants that dominate them possess an array of traits that deter consumption by forest pests. Although often extremely effective against native consumers, invasive species that avoid or overcome these defenses can wreak havoc on trees and surrounding ecosystems. This is especially true when multiple invasive species co-occur, since interactions between invasive herbivores may yield non-additive effects on the host.

Asymmetric biotic interactions and abiotic niche differences revealed by a dynamic joint species distribution model.

A species' distribution and abundance are determined by abiotic conditions and biotic interactions with other species in the community. Most species distribution models correlate the occurrence of a single species with environmental variables only, and leave out biotic interactions. To test the importance of biotic interactions on occurrence and abundance, we compared a multivariate spatiotemporal model of the joint abundance of two invasive insects that share a host plant, hemlock woolly adelgid (HWA; Adelges tsugae) and elongate hemlock scale (EHS; Fiorina externa), to independent models that do not account for dependence among co-occurring species.

Two invasive herbivores on a shared host: patterns and consequences of phytohormone induction.

Herbivore-induced changes in host quality mediate indirect interactions between herbivores. The nature of these indirect interactions can vary depending on the identity of herbivores involved, species-specific induction of defense-signaling pathways, and sequence of attack. However, our understanding of the role of these signaling pathways in the success of multiple exotic herbivores is less known.

Seasonal variation in effects of herbivory on foliar nitrogen of a threatened conifer.

Invasive herbivores can dramatically impact the nitrogen (N) economy of native hosts. In deciduous species, most N is stored in stem tissues, while in evergreen conifer species N is stored in needles, making them potentially more vulnerable to herbivory. In eastern forests of the USA, the long-lived, foundational conifer eastern hemlock () is under the threat of extirpation by the invasive hemlock woolly adelgid (HWA: ).

Non-target effects of fungicides on nectar-inhabiting fungi of almond flowers.

Nectar mediates interactions between plants and pollinators in natural and agricultural systems. Specialized microorganisms are common nectar inhabitants, and potentially important mediators of plant-pollinator interactions. However, their diversity and role in mediating pollination services in agricultural systems are poorly characterized.

Nectar yeasts in the tall Larkspur Delphinium barbeyi (Ranunculaceae) and effects on components of pollinator foraging behavior.

Microorganisms frequently colonize the nectar of angiosperm species. Though capable of altering a suite of traits important for pollinator attraction, few studies exist that test the degree to which they mediate pollinator foraging behavior. The objective of our study was to fill this gap by assessing the abundance and diversity of yeasts associated with the perennial larkspur Delphinium barbeyi (Ranunculaceae) and testing whether their presence affected components of pollinator foraging behavior.

Yeasts in nectar enhance male fitness in a montane perennial herb.

Floral nectar of many plant species is prone to colonization by microbial organisms such as yeasts. Their presence and metabolism of nectar chemical components have the potential to modify a suite of floral traits important for pollinator attraction, including nectar quality and scent. However, studies on the direct and indirect effects of nectar-inhabiting microorganisms on pollinator behavior and plant reproductive success remain rare.

Effects of abiotic factors and species interactions on estimates of male plant function: a meta-analysis.

The majority of angiosperms are hermaphroditic with total fitness comprised of both male and female components of reproduction. However, most studies examining the effects of abiotic factors and species interactions on fitness have focussed on female reproduction, potentially biasing our understanding of the consequences of environmental factors on total fitness. Here, we use meta-analysis to test how environmental factors affect male function.