Entomology Commons^™

Knockdown Of Rna Interference Pathway Genes In Western Corn Rootworms (Diabrotica Virgifera Virgifera Le Conte) Demonstrates A Possible Mechanism Of Resistance To Lethal Dsrna, Ana María Vélez, Chitvan Khajuria, Haichuan Wang, Kenneth E. Narva, Blair D. Siegfried

Department of Entomology: Faculty Publications

RNA interference (RNAi) is being developed as a potential tool for insect pest management. Increased understanding of the RNAi pathway in target insect pests will provide information to use this technology effectively and to inform decisions related to resistant management strategies for RNAi based traits. Dicer 2 (Dcr2), an endonuclease responsible for formation of small interfering RNA’s and Argonaute 2 (Ago2), an essential catalytic component of the RNA-induced silencing complex (RISC) have both been associated with the RNAi pathway in a number of different insect species including the western corn rootworm, Diabrotica virgifera virgifera (Coleoptera: Chrysomelidae). We identified both genes …

Duplication And Remolding Of Trna Genes In The Mitochondrial Genome Of Reduvius Tenebrosus (Hemiptera: Reduviidae), Pei Jiang, Hu Li, Fan Song, Yao Cai, Jianyun Wang, Jinpeng Liu, Wanzhi Cai

Markey Cancer Center Faculty Publications

Most assassin bugs are predators that act as important natural enemies of insect pests. Mitochondrial (mt) genomes of these insects are double-strand circular DNAs that encode 37 genes. In the present study, we explore the duplication and rearrangement of tRNA genes in the mt genome of Reduvius tenebrosus, the first mt genome from the subfamily Reduviinae. The gene order rearranges from CR (control region)-trnI-trnQ-trnM-ND2 to CR-trnQ-trnI2-trnI1-trnM-ND2. We identified 23 tRNA genes, including 22 tRNAs commonly found in insects and an additional trnI (trnI2), which has high sequence similarity to trnM. We found several …

Exploration Of Chemical And Biological Management Strategies For Diaphorina Citri The Primary Vector Of Candidatus Liberibacter Asiaticus, Gretta Marie Sharp

Biology Theses

Diaphorina citri (Hemipteran: Psyllidae), the Asian citrus psyllid, is a phloem-feeding, invasive species endemic to southern Asia that was first identified in the United States in Florida in 1998. Since introduction, D. citri has spread across the major citrus growing regions of the United States. This is of great concern to the citrus industry because D. citri is the primary vector of Candidatus Liberibacter asiaticus the causal agent of Haunglongbing (HLB). Haunglongbing is the most economically devastating disease of citrus causing an estimated 8.92 billion dollars lost in revenue and 4.62 billion dollars lost in gross domestic product between 2006-2007 …

Identification Of Ecdysone Hormone Receptor Agonists As A Therapeutic Approach For Treating Filarial Infections, Amruta S. Mhashilkar, Sai L. Vankayala, Canhui Liu, Fiona Kearns, Priyanka Mehrotra, George Tzertzinis, Subba R. Palli, H. Lee Woodcock, Thomas R. Unnasch

Entomology Faculty Publications

Background A homologue of the ecdysone receptor has previously been identified in human filarial parasites. As the ecdysone receptor is not found in vertebrates, it and the regulatory pathways it controls represent attractive potential chemotherapeutic targets.

Methodology/ Principal Findings Administration of 20-hydroxyecdysone to gerbils infected with B. malayi infective larvae disrupted their development to adult stage parasites. A stable mammalian cell line was created incorporating the B. malayi ecdysone receptor ligand-binding domain, its heterodimer partner and a secreted luciferase reporter in HEK293 cells. This was employed to screen a series of ecdysone agonist, identifying seven agonists active at …

Identification Of G Protein-Coupled Receptors Required For Vitellogenin Uptake Into The Oocytes Of The Red Flour Beetle, Tribolium Castaneum, Hua Bai, Subba R. Palli

Entomology Faculty Publications

Previous studies suggested that a membrane receptor might be involved in mediating vitellogenin (Vg) uptake and juvenile hormone (JH)-regulated remodeling of follicular epithelium (also called ‘patency’). G protein-coupled receptor (GPCR) family is one of the largest membrane receptor protein families and controls many key physiological processes. To investigate the role of GPCRs in insect reproduction and juvenile hormone-regulated Vg uptake, we performed a comprehensive RNA interference (RNAi) screen targeting GPCRs in the red flour beetle, Tribolium castaneum. Out of 112 GPCRs tested, knockdown of 41 GPCRs resulted in a reduction in fecundity. Interestingly, RNAi against two GPCRs (a Rhodopsin-like …

A 2-Cys Peroxiredoxin In Response To Oxidative Stress In The Pine Wood Nematode, Bursaphelenchus Xylophilus, Zhen Li, Qingwen Zhang, Xuguo Zhou

Entomology Faculty Publications

The pine wood nematode, Bursaphelenchus xylophilus, is the causal agent of pine wilt disease that has devastated pine forests in Asia. Parasitic nematodes are known to have evolved antioxidant stress responses that defend against host plant defenses. In this study, the infestation of whitebark pine, Pinus bungean, with B. xylophilus led to a significant increase in plant hydrogen peroxide (H₂O₂) and salicylic acid levels. Correspondingly, the expression of an antioxidative enzyme, 2-Cysteine peroxiredoxin (BxPrx), was elevated in B. xylophilus following the H₂O₂ treatments. Recombinant BxPrx, a thermal stabile and pH tolerant …

Nebline, June 2016

NEBLINE Newsletter Archive from Nebraska Extension in Lancaster County

Feature: The Garden Grocery — Food Safety & Selection at Farmers’ Markets

Food & Health

Farm & Acreage

Pests & Wildlife

Horticulture

Early Childhood

4-H & Youth

Extension Calendar

and other extension news and events

Rnai Induced Knockdown Of A Cadherin-Like Protein (Ef531715) Does Not Affect Toxicity Of Cry34/35ab1 Or Cry3aa To Diabrotica Virgifera Virgifera Larvae (Coleoptera: Chrysomelidae), Sek Yee Tan, Murugesan Rangasamy, Haichuan Wang, Ana Maria Vélez, James Hasler, David Mccaskill, Tao Xu, Hong Chen, Jessica Jurzenski, Matthew Kelker, Xiaoping Xu, Kenneth E. Narva, Blair D. Siegfried

Department of Entomology: Faculty Publications

The western corn rootworm (WCR), Diabrotica virgifera virgifera LeConte, is an important maize pest throughout most of the U.S. Corn Belt. Bacillus thuringiensis (Bt) insecticidal proteins including modified Cry3Aa and Cry34/35Ab1 have been expressed in transgenic maize to protect against WCR feeding damage. To date, there is limited information regarding the WCR midgut target sites for these proteins. In this study, we examined whether a cadherin-like gene from Diabrotica virgifera virgifera (DvvCad; Gen-Bank accession # EF531715) associated with WCR larval midgut tissue is necessary for Cry3Aa or Cry34/ 35Ab1 toxicity. Experiments were designed to examine the sensitivity of WCR to …

Low Permeability Triple-Layer Plastic Bags Prevent Losses Of Maize Caused By Insects In Rural On-Farm Stores, Jeremiah Ng’Ang’A, Christopher Mutungi, Samuel M. Imathiu, Hippolyte Affognon

All Peer-Reviewed Publications

Participatory on-farm trials were conducted to assess effectiveness of Purdue Improved Crop Storage (PICS™) bags for storage of maize in small-scale farmers’ stores in rural villages in eastern Kenya. A PICS bag is a three-layered hermetic bag-system that forms a barrier against the influx of oxygen and the escape of carbon dioxide. Jute, woven polypropylene or PICS bags were filled with shelled maize grain, purchased from the participating farmers, and the three sets of bags kept in the farmers’ own stores for 35 weeks. Oxygen and carbon dioxide levels in the PICS bags were monitored, as well as the temperature …

Molecular Identification Of Different Trypanosome Species And Subspecies In Tsetse Flies Of Northern Nigeria, Clement Isaac, Marc Ciosi, Alana Hamilton, Kathleen Maria Scullion, Peter Dede, Igho Benjamin Igbinosa, Oyebiguwa Patrick Goddey Nmorsi, Dan Masiga, C. Michael R. Turner

All Peer-Reviewed Publications

Background: Animal African Trypanosomiasis (AAT) is caused by several species of trypanosomes including Trypanosoma congolense, T. vivax, T. godfreyi, T. simiae and T. brucei. Two of the subspecies of T. brucei also cause Human African Trypanosomiasis. Although some of them can be mechanically transmitted by biting flies; these trypanosomes are all transmitted by tsetse flies which are the cyclical vectors of Trypanosoma congolense, T. godfreyi, T. simiae and T. brucei. We present here the first report assessing the prevalence of trypanosomes in tsetse flies in Nigeria using molecular tools. Methods: 488 tsetse flies of three species, Glossina palpalis palpalis, G. …

Dynamics Of Two Pathogens In A Single Tick Population, Alexis White

Biology and Medicine Through Mathematics Conference

No abstract provided.

Hands Of The Future, Inc; Junior Nature Club; Living Schoolyards, Zonda K. Bryant

Purdue P-12 Networking Summit & Poster Session

Programs to connect children to nature

Krüppel Homolog 1 And E93 Mediate Juvenile Hormone Regulation Of Metamorphosis In The Common Bed Bug, Cimex Lectularius, Hemant Gujar, Subba Reddy Palli

Entomology Faculty Publications

The common bed bug is an obligate hematophagous parasite of humans. We studied the regulation of molting and metamorphosis in bed bugs with a goal to identify key players involved. qRT-PCR studies on the expression of genes known to be involved in molting and metamorphosis showed high levels of Krüppel homolog 1 [Kr-h1, a transcription factor that plays key roles in juvenile hormone (JH) action] mRNA in the penultimate nymphal stage (N4). However, low levels of Kr-h1 mRNA were detected in the fifth and last nymphal stage (N5). Knockdown of Kr-h1 in N4 resulted in a precocious development of adult …

Tropical Trees As Islands: Diversity Accumulation Of Armored Scale Insects (Hemiptera: Diaspididae) On Trees As A Function Of Forest Age, Hannah Shapiro

Undergraduate Honors Theses

Armored scale insects (Hemiptera: Diaspididae) are some of the most invasive insects in the world. These cryptic plant parasites are most often encountered in managed agricultural ecosystems, but very little is known about their distribution, abundance, and diversity in tropical rainforest canopies, where they are likely to have their highest diversity. Because these ubiquitous insects are extreme generalists with undirected dispersal, their diversity (alpha and beta) accumulation can conceivably be modeled according to tenets derived from island biogeography theory. For example, one expectation is that older established trees should boast a higher species diversity and abundance than younger ones. Other …

Can Climate-Driven Change Influence Silicon Assimilation By Cereals And Hence The Distribution Of Lepidopteran Stem Borers In East Africa?, P. A. Calatayud, E. Njuguna, S. Mwalusepo, M. Gathara, G. Okuku, A. Kibe, B. Musyoka, D. Williamson, G. Ong'amo, G. Juma, T. Johansson, S. Subramanian, E. Gatebe, B. Le Ru

All Peer-Reviewed Publications

In East Africa, lepidopteran stemborers such as Chilo partellus and Busseola fusca are major constraints to production of maize, which is the main staple food crop in the region. Cereals depend on silicon (Si)-based defences to fight off herbivores. Using altitudinal ranges in the East African highlands as ecological surrogates for inferring climate change, it was shown that Si concentrations in soil and maize decreased with altitude. This was attributed, in part, to low temperatures at high altitudes, which negatively affected Si assimilation by maize. Experiments showed that B. fusca was more susceptible to Si than C. partellus. Hence the …

Trox Paulseni (Coleoptera: Trogidae), A New Species From Nebraska And Kansas, Usa, Brett C. Ratcliffe

Insecta Mundi

Trox paulseni Ratcliffe, new species (Coleoptera: Trogidae), is described from Nebraska and Kansas, USA. A description, diagnosis to separate it from Trox hamatus Robinson (its closest congener), distribution, and illustrations are provided.

Determining The Pollination Mechanism Of A Problematic Invasive Species In The Gulf South: Triadica Sebifera, Jennifer Wester Clark

LSU New Orleans Theses and Dissertations

Understanding the ecology of invasive species is vital to curb the homogenizing of ecosystems, yet the pollination mechanisms of the Chinese tallow tree (Triadica sebifera) in its introduced habitat remain ambiguous. This study examines self-pollination, wind pollination, and flower-visiting insects of tallow in a bottomland hardwood forest and Longleaf pine savannah in the U.S. Gulf South. These data suggest that self-pollination and airborne pollination are possible, but likely rare occurrences, although the possibility of apoxisis was not investigated. Seed production in exclusion experiments was significantly less than in open-pollinated flowers, and wind dispersal of tallow pollen dropped to …

The Effects Of Forest Age And Management On Bee Communities Of Production Forests In The Southern United States, Robinson Sudan

LSU New Orleans Theses and Dissertations

Processes structuring bee communities in agricultural landscapes are well-documented compared to those in other anthropogenic landscapes, like production forests. Forests across the temperate zone have historically been under-sampled, in part due to the perception that they provide little habitat to support diverse bee communities. While research suggests that early successional habitats support high levels of bee species richness and abundance, little empirical evidence exists to support the notion that forests, in turn, do not. To understand the relationship between forest successional age and major elements of the bee community, I sampled bees in a southern production pine forest in Hancock …

Gravid Anopheles Gambiae Sensu Stricto Avoid Ovipositing In Bermuda Grass Hay Infusion And It's Volatiles In Two Choice Egg-Count Bioassays, Lynda K. Eneh, Michael N. Okal, Anna Karin Borg-Karlson, Ulrike Fillinger, Jenny M. Lindh

All Peer-Reviewed Publications

Background: A number of mosquito species in the Culex and Aedes genera prefer to lay eggs in Bermuda grass (Cynodon dactylon) hay infusions compared to water alone. These mosquitoes are attracted to volatile compounds from the hay infusions making the infusions effective baits in gravid traps used for monitoring vectors of arboviral and filarial pathogens. Since Bermuda grass is abundant and widespread, it is plausible to explore infusions made from it as a potential low cost bait for outdoor monitoring of the elusive malaria vector Anopheles gambiae s.s. Methods: This study investigated preferential egg laying of individual An. gambiae s.s. …

Escape Strategy Of The Cockroach (Gromphadorhina Portentosa) To Heat And Looming Stimuli, Jiangda Ou

Senior Honors Projects, 2010-2019

Escape responses to aversive stimuli have been observed in insects, including species of cricket, fly, locust, and cockroach. The goal of this study was to investigate the escape strategy of the Madagascar cockroach, Gromphadorhina portentosa. In regard to this species, Erickson and colleagues (2015) showed that electrical stimulation of both cerci and antennae together could generate an escape response. However, in other reports (Olsen and Triblehorn, 2014), it was observed that wind could not elicit the escape response. In this study, G. portentosa was stimulated by looming and heat stimuli. A 2.5’’ black ball approaching at 1 m/s was used …

Large-Plot Field Studies To Assess Impacts Of Newer Insecticides On Non-Target Arthropods In Western U.S. Orchards, Peter W. Shearer, Kaushalya G. Amarasekare, Steven P. Castagnoli, Elizabeth H. Beers, Vincent P. Jones, Nicholas J. Mills

Agricultural and Environmental Sciences Faculty Research

The non-target impacts of two reduced risk insecticides, chlorantraniliprole and spinetoram, were evaluated for two years in Oregon pear and California walnut orchards. Experiments were conducted in large replicated plots (approximately 0.25–0.4ha) to assess the impact of these two insecticides on natural enemies of secondary pests when applied against codling moth, Cydia pomonella. Cumulative insect days (CID) of secondary pests and natural enemies were calculated from leaf samples, plant volatile traps, beat trays or cardboard trunk bands. Ratios of natural enemies and prey were also calculated. Results from these field studies demonstrate that applications of chlorantraniliprole can reduce abundance of …

A Brief History Of Corn: Looking Back To Move Forward, Jon Derek Pruitt

Doctor of Plant Health Program: Dissertations and Student Research

Maize was domesticated from teosinte in Mexico some 7,000 to 10,000 years ago and quickly spread through the Americas. It has become one of the most important crops at a local and global level. Two types, Northern Flint corn and Southern Dent corns provided the basis of the genetic background of modern maize hybrids. The development of hybrids, first double-cross and later single-cross hybrids, along with a transition to high input farming provided huge yield increases, which have continued to improve with improving technology.

Increase in maize production also caused a rise in Western corn Rootworm (Diabrotica virgifera virgifera …

A New Species Of Dinonigidius De Lisle From Sri Lanka (Coleoptera: Lucanidae), M. J. Paulsen

Insecta Mundi

Dinonigidius bartolozzii Paulsen, new species, (Coleoptera: Lucanidae) is described from Sri Lanka, and compared with the only other species of the genus, D. ahenobarbus de Lisle from India.

The Influence Of Beached Harmful Algal Blooms On Terrestrial Arthropods On The Shore Of Lake Erie, Nadejda Mirochnitchenko, Kevin E. Mccluney

Honors Projects

Marine primary inputs, such as sea wrack and algae, offer a great niche for insects and other animals to exploit. The existence of a similar niche on the coast of lakes has received less attention. To complicate matters, many freshwater systems are seeing increases in proliferation of toxic and non-toxic cyanobacteria blooms. This study examined patterns in lake shore terrestrial arthropod abundance, diversity, and community composition across gradients of beached algae, with varying toxicity. We detected water microcystin effects on arthropod richness in survey three, beached material effects on Shannon’s Diversity in survey two, and water microcystin effects on the …

Nocturnal Foraging Enhanced By Enlarged Secondary Eyes In A Net-Casting Spider, Jay A. Stafstrom, Eileen A. Hebets

Eileen Hebets Publications

Animals that possess extreme sensory structures are predicted to have a related extreme behavioral function. This study focuses on one such extreme sensory structure—the posterior median eyes of the net-casting spider Deinopis spinosa. Although past research has implicated the importance of vision in the nocturnal foraging habits of Deinopis, no direct link between vision in the enlarged eyes and nocturnal foraging has yet been made. To directly test the hypothesis that the enlarged posterior median eyes facilitate visually based nocturnal prey capture, we conducted repeated-measures, visual occlusion trials in both natural and laboratory settings. Our results indicate that D. …

Relationships Between Nutrients, Periphyton Abundance, And Benthic Macroinvertebrate Scrapers In Ozark Highland Streams, Harrison Smith

Biological Sciences Undergraduate Honors Theses

We collected samples from seven Arkansas streams during the months of August 2014 and February 2015 with the objective of determining possible relationships between nutrients, periphyton abundance and benthic macroinvertebrates. We hypothesized that periphyton would be positively associated with nutrients, and that increases in periphyton biomass would increase the abundance and diversity of benthic scraper families. Samples were collected from three transects at each site. The periphyton was analyzed for carbon, nitrogen, phosphorus, and ash free dry mass and Chl-a content. Macroinvertebrates families belonging to the feeding group of grazers/scrapers were compared with water column and periphyton nutrient concentrations, as …

Hexapod Herald - Vol. 28, No. 2, May 2016

Hexapod Herald and Other Entomology Department Newsletters

Contents: Welcome - Congratulations - Publications - Faculty News - Grants - Student News - Travel

The Mayfly Newsletter, Peter M. Grant

The Mayfly Newsletter

The Mayfly Newsletter is the official newsletter of the Permanent Committee of the International Conferences on Ephemeroptera.

Nebline, May 2016

NEBLINE Newsletter Archive from Nebraska Extension in Lancaster County

Feature: Emerald Ash Borer is Getting Closer

Food & Health

Family Living

Farm & Acreage

Horticulture

Pests & Wildlife

4-H & Youth

Extension Calendar

and other extension news and events

Characterization Of Glycine Rich Proteins From The Salivary Glands Of The Lone Star Tick Amblyomma Americanum, Rebekah Lynn Bullard

Dissertations

Ticks are blood sucking arthropods that feed on living hosts for up to three weeks. The ticks secrete a multitude of pharmacologically active proteins into the host during feeding which allow the tick to avoid the host immune response, establish a blood pool, and form a firm attachment. The firm attachment is facilitated by the formation of a cement cone which surrounds the tick mouthparts and intertwine between the host skin layers. In this study, gene expression of 44 A. americanum genes was measured throughout the bloodmeal to reveal the differential expression of these genes. Each of the genes tested …