Life Sciences Commons^™

Non-Native Non-Apis Bees Are More Abundant On Non-Native Versus Native Flowering Woody Landscape Plants, Daniel A. Potter, Bernadette M. Mach

Entomology Faculty Publications

Urban ecosystems can support diverse communities of wild native bees. Because bloom times are conserved by geographic origin, incorporating some non-invasive non-native plants in urban landscapes can extend the flowering season and help support bees and other pollinators during periods when floral resources from native plants are limiting. A caveat, though, is the possibility that non-native plants might disproportionately host non-native, potentially invasive bee species. We tested that hypothesis by identifying all non-native bees among 11,275 total bees previously collected from 45 species of flowering woody landscape plants across 213 urban sites. Honey bees, Apis mellifera L., accounted for 22% …

A Versatile Contribution Of Both Aminopeptidases N And Abc Transporters To Bt Cry1ac Toxicity In The Diamondback Moth, Dan Sun, Liuhong Zhu, Le Guo, Shaoli Wang, Qingjun Wu, Neil Crickmore, Xuguo Zhou, Alejandra Bravo, Mario Soberón, Zhaojiang Guo, Youjun Zhang

Entomology Faculty Publications

BACKGROUND: Biopesticides and transgenic crops based on Bacillus thuringiensis (Bt) toxins are extensively used to control insect pests, but the rapid evolution of insect resistance seriously threatens their effectiveness. Bt resistance is often polygenic and complex. Mutations that confer resistance occur in midgut proteins that act as cell surface receptors for the toxin, and it is thought they facilitate its assembly as a membrane-damaging pore. However, the mechanistic details of the action of Bt toxins remain controversial.

RESULTS: We have examined the contribution of two paralogous ABC transporters and two aminopeptidases N to Bt Cry1Ac toxicity in the diamondback moth, …

Mapk-Mediated Transcription Factor Gatad Contributes To Cry1ac Resistance In Diamondback Moth By Reducing Pxmalp Expression, Le Guo, Zhouqiang Cheng, Jianying Qin, Dan Sun, Shaoli Wang, Qingjun Wu, Neil Crickmore, Xuguo Zhou, Alejandra Bravo, Mario Soberón, Zhaojiang Guo, Youjun Zhang

Entomology Faculty Publications

The benefits of biopesticides and transgenic crops based on the insecticidal Cry-toxins from Bacillus thuringiensis (Bt) are considerably threatened by insect resistance evolution, thus, deciphering the molecular mechanisms underlying insect resistance to Bt products is of great significance to their sustainable utilization. Previously, we have demonstrated that the down-regulation of PxmALP in a strain of Plutella xylostella (L.) highly resistant to the Bt Cry1Ac toxin was due to a hormone-activated MAPK signaling pathway and contributed to the resistance phenotype. However, the underlying transcriptional regulatory mechanism remains enigmatic. Here, we report that the PxGATAd transcription factor (TF) is responsible for the …

Reproductive Diapause In The Ladybird Beetle Cycloneda Munda, John J. Obrycki

Lady Beetle Research Data

Adult Cycloneda munda were collected from Fayette County, Kentucky (38.12°N, 84.54°W). Eggs were collected daily from 4 to 6 females and placed in L:D 16:8, 14:10, 12:12,10:14, at 22°C ± 1.0°C. F1 offspring were individually reared in glass vials at each photoperiod on pea aphids and Ephestia kuehniella eggs to examine the effects of photoperiod on development (Data file 1: C-munda-Dev-Times-at-LD.jmp). Comparisons of the developmental responses to the four LD treatments were made. Pairs of F1 Cycloneda munda adults were maintained at the same larval photoperiod. Pairs were fed and maintained at each photoperiod for 110 days. The date of …

Net Effects Of Wild And Managed Birds In Agroecosystems, Karina Garcia

Theses and Dissertations--Entomology

Agricultural intensification and expansion have reduced biodiversity in agroecosystems, jeopardizing the ecosystem services that nature provides to humans in these landscapes including wildlife-mediated pest control. Among these purveyors of ecosystem services are birds, who can provide services to agroecosystems by consuming arthropod pests. Yet some bird species also act as pests by consuming crops. Herein, I use molecular diet analysis through high-throughput sequencing on DNA extracted from bird fecal samples to examine birds’ diet and classify bird species as consumers of major strawberry pests (Lygus spp.). Additionally, I use targeted PCR approaches to determine which bird species consumed strawberries. …

A Functional Genomics Approach To Overwintering Mechanisms In Insects, Emily Allison Wheeler Nadeau

Theses and Dissertations--Entomology

Insects living in temperate and polar environments have developed numerous adaptations to increase survival at low temperatures. A majority of insects are freeze-intolerant and die from internal ice formation, but some are freeze-tolerant and can survive ice formation in extracellular spaces. Both categories of insects prepare for winter with a combination of seasonal and rapid acclimation responses, which differ both in time course and in underlying mechanisms. In this dissertation, I examine adaptations for winter survival in several insect species with a specific focus on molecular mechanisms. To better understand the underpinning mechanisms of these adaptations, I leverage functional genomics …

Effects Of Physiological Stage And Diet On Drosophila Suzukii Olfaction, Aerianna Shindindowi Littler

Theses and Dissertations--Entomology

Massive economic damage by spotted-wing drosophila (SWD), Drosophila suzukii, results from their unique egg laying behavior. Gravid SWD flies employ a complex suite of behaviors to find fruit with the optimum firmness and chemistry. We tested for SWD attraction to various fruits and found overripe raspberries to be most attractive to gravid flies which was unexpected since they oviposit in ripe fruit. We next tested the same choice assay in a T-maze and found that the results were comparable. We also found discrete odor profiles among the ripening stages. When testing for sugars and CO2 concentrations from field-collections, overripe …

Gene Silencing Provides Insights Into Bark Beetle Biology And Creates Potential For Broad Scale Forest Protection, Beth R. Kyre

Theses and Dissertations--Entomology

Dendroctonus bark beetles are among the most economically and ecologically significant forest pests in North America and play a critical role in the overall health of conifer forest ecosystems. Dendroctonus bark beetles influence ecosystem benefits and biodiversity and drive forest succession, and adversely affect timber production, forest management, and recreation. As temperatures surge and climatic fluctuations become more extreme, catastrophic bark beetle outbreaks are increasing in frequency, escalating pressures on highly vulnerable conifer forests already compromised by heat and drought. Eruptive outbreaks of Dendroctonus beetles are largely unhindered by traditional silvicultural management; these practices further disrupt forest ecosystem services, including …

Rna Interference For Emerald Ash Borer Suppression: Ecotoxicological Assessment And Delivery Methods, Flavia Pampolini

Theses and Dissertations--Entomology

The emerald ash borer (EAB), Agrilus planipennis (Coleoptera: Buprestidae), is a highly invasive phloem-feeding insect native to Asia. It has killed millions of ash trees (Fraxinus spp.) since its accidental introduction into North America, causing profound economic and ecological impacts. RNA interference (RNAi) or double-stranded RNA (dsRNA)-mediated gene silencing is an emerging biotechnology that is developing as an innovative tool for pest management. Exogenous dsRNA triggers the RNAi pathway, silences genes, and disrupts protein function, causing insect mortality. RNAi has proven effective in reducing target gene expression and causing mortality in EAB; however, two aspects stand as barriers …