Entomology Commons^™

Gene Silencing In Tribolium Castaneum As A Tool For The Targeted Identification Of Candidate Rnai Targets In Crop Pests, Eileen Knorr, Elane Fishilevich, Linda Tenbusch, Meghan L. F. Frey, Murugesan Rangasamy, Andre Billion, Sarah E. Worden, Premchand Gandra, Kanika Arora, Wendy Lo, Greg Schulenberg, Pablo Valverde-Garcia, Andreas Vilcinskas, Kenneth E. Narva

Department of Entomology: Faculty Publications

RNAi shows potential as an agricultural technology for insect control, yet, a relatively low number of robust lethal RNAi targets have been demonstrated to control insects of agricultural interest. In the current study, a selection of lethal RNAi target genes from the iBeetle (Tribolium castaneum) screen were used to demonstrate efficacy of orthologous targets in the economically important coleopteran pests Diabrotica virgifera virgifera and Meligethes aeneus. Transcript orthologs of 50 selected genes were analyzed in D. v. virgifera diet-based RNAi bioassays; 21 of these RNAi targets showed mortality and 36 showed growth inhibition. Low dose injection- and …

Clathrin-Dependent Endocytosis Is Associated With Rnai Response In The Western Corn Rootworm, Diabrotica Virgifera Virgifera Leconte, Daniele H. Pinheiro, Ana M. Velez, Elane Fishilevich, Haichuan Wang, Newton P. Carneiro, Arnubio Valencia-Jimenez, Fernando H. Valicente, Kenneth E. Narva, Blair D. Siegfried

Department of Entomology: Faculty Publications

The cellular uptake of dsRNA after dietary exposure is critical for RNAi efficiency; however, the mechanism of its uptake in many insects remains to be understood. In this study, we evaluated the roles of the endocytic pathway genes Clathrin heavy chain (Chc), Clathrin adaptor protein AP50, ADP ribosylation factor-like 1 (Arf72A), Vacuolar H⁺ ATPase 16 kDa subunit (Vha16), and small GTPase Rab7 and putative sid-1-like genes (silA and silC) in RNAi response in western corn rootworm (WCR) using a two-stage dsRNA exposure bioassay. Silencing of Chc, Vha16, and AP50 led …

The Mysteries Of Insect Rnai: A Focus On Dsrna Uptake And Transport, Ana Maria Vélez, Elane Fishilevich

Department of Entomology: Faculty Publications

RNA interference (RNAi) is becoming a practical tool to control insect pests. Many mysteries of how double-stranded RNA (dsRNA) is transported into, within, and between cells to generate an efficient RNAi response in insects are still to be unraveled. This review provides an overview of the evidence that supports a key role of endocytosis in the uptake of dsRNA on both cellular and tissue levels. Additionally, other components of cellular membrane transport and their impact on the efficiency of RNAi in insects are explored. It is now evident that the membrane transport and potentially dsRNA release from the endosome may …

Rapid And Persistent Rnai Response In Western Corn Rootworm Adults, Ke Wu, Caitlin E. Taylor, Elane Fishilevich, Kenneth E. Narva, Blair Siegfried

Department of Entomology: Faculty Publications

RNA interference (RNAi) has proven effective for controlling pest insects such as western corn rootworm (WCR), Diabrotica virgifera virgifera (Coleoptera: Chrysomelidae). Previous studies have shown that WCR adults display a robust RNAi response to orally-administered double-stranded RNA (dsRNA). However, it is unclear how quickly the response occurs after ingestion or how long RNAi effect lasts after WCR stop ingesting diet containing dsRNA. In the current study, WCR adult females were provided with diet treated with dsRNAs of Laccase 2 and Argonaute 2, two nonessential genes, for 8 days. RNAi response in WCR females commenced as early as 10 h …

Knockdown Of Rna Interference Pathway Genes In Western Corn Rootworm, Diabrotica Virgifera Virgifera, Identifies No Fitness Costs Associated With Argonaute 2 Or Dicer-2, Carolina Camargo, Ke Wu, Elane Fishilevich, Kenneth E. Narva, Blair Siegfried

Department of Entomology: Faculty Publications

The use of transgenic crops that induce silencing of essential genes using double-stranded RNA (dsRNA) through RNA interference (RNAi) in western corn rootworm, Diabrotica virgifera virgifera, is likely to be an important component of new technologies for the control of this important corn pest. Previous studies have demonstrated that the dsRNA response in D. v. virgifera depends on the presence of RNAi pathway genes including Dicer-2 and Argonaute 2, and that down-regulation of these genes limits the lethality of environmental dsRNA. A potential resistance mechanism to lethal dsRNA may involve loss of function of RNAi pathway genes. However, …

The Ancognatha Erichson (Coleoptera: Scarabaeidae: Dynastinae: Cyclocephalini) Of Ecuador, With Description Of A New Species, Aura Paucar-Cabrera, Brett C. Ratcliffe

Department of Entomology: Faculty Publications

Descriptions, diagnoses, locality and temporal records, distributional maps, and illustrations of the 11 species of Ancognatha Erichson occurring in Ecuador are provided. Four new country records are reported for Ecuador, and a new species is described. A female lectotype at the Natural History Museum (London) for Ancognatha jamesoni Murray is designated. A key to the Ecuadorian species is included.

Se proporcionan descripciones, diagnosis, localidades y meses de colecta, mapas de distribuci´on e ilustraciones de las 11 especies de Ancognatha Erichson que se encuentran en Ecuador. Se reportan cuatro registros nuevos para el pa´ıs y se describe una especie nueva. …

Ganganomala Saltini Ratcliffe, Jameson, And Zorn, A Newgenus And Species Ofanomalini (Coleoptera: Scarabaeidae: Rutelinae) From Bangladesh And Nepal, With A Revised Circumscription Of The Tribe, Brett C. Ratcliffe, Mary Liz Jameson, Carsten Zorn

Department of Entomology: Faculty Publications

Ganganomala saltini Ratcliffe, Jameson, and Zorn, a new genus and new species of Anomalini (subtribe Anomalina), is described fromBangladesh and Nepal. To place the new genus within the context of the tribe and subtribe, we provide a key to the four subtribes of world Anomalini, a list of comparative characters and character states for diagnosis and classification of Old World Anomalina, and comparative diagnostic characters for genera of Old World Anomalina. Circumscription, description, diagnosis, and illustrations for the new genus and species are provided. As a result of this research, the Anomalina includes 50 genera and subgenera, and advances our …

Description Of A New Species Of Stenocrates Burmeister (Coleoptera: Scarabaeidae: Dynastinae: Cyclocephalini) From Peru, Brett C. Ratcliffe, Luis Figueroa

Department of Entomology: Faculty Publications

A new species of Stenocrates Burmeister, 1847 (Coleoptera: Scarabaeidae: Dynastinae: Cyclocephalini) from Peru is described: Stenocrates lissothorax Ratcliffe and Figueroa.Adescription, diagnosis, distribution, and illustrations of the new species are provided. This represents the 52nd species in the genus, and the 15th species known from Peru.

Parental Rnai Suppression Of Kruppel Gene To Control Hemipteran Pests, Blair D. Siegfried, Kenneth E. Narva, Kanika Arora, Sarah E. Worden, Chitvan Khajuria, Elane Fishilevich, Nicholas P. Storer, Meghan Frey, Ronda L. Hamm, Ana Velez

Department of Entomology: Faculty Publications

This disclosure concerns nucleic acid molecules and methods of use thereof for control of hemipteran pests through RNA interference - mediated inhibition of target coding and transcribed non - coding sequences in hemipteran pests. The disclosure also concerns methods for making transgenic plants that express nucleic acid molecules useful for the control of hemipteran pests, and the plant cells and plants obtained thereby.

Can Increasing Grass-Fungal Endophyte Symbiotic Diversity Enhance Grassland Ecosystem Functioning?, Mahtaab Bagherzadeh

Theses and Dissertations--Plant and Soil Sciences

The relationship between biodiversity and ecosystem functioning is important in maintaining agroecosystem sustainability. Plant-microbe symbioses, such as exists between the grass tall fescue (Schedonorus arundinaceum) and the asexual fungal endophyte Epichloë coenophiala, can be utilized to enhance agroecosystem functions, such as herbivore resistance. “Novel” E. coenophiala strains that vary in the production of mammal- and insect-toxic compounds have been identified, inserted into tall fescue cultivars, and are planted in pastures globally. Novel fungal endophyte-tall fescue associations may have divergent ecosystem function effects. This study assessed effects of different fescue-endophyte symbiotic combinations on pasture ecosystem function, including aboveground …

Jeweled Spider Flies (Eulonchus Tristis) Are Important Pollinators Of Iris Bracteata, A Rare Siskiyou Mountain Endemic, Jean-Paul E. Ponte

Cal Poly Humboldt theses and projects

Little is known about the pollination biology of the Pacific Coast Irises (Iris: series Californicae, hereafter PCI), especially who visits and pollinates their flowers. In general, Iris flowers are considered bee-pollinated, however, flies in the genus Eulonchus (Acroceridae) are known to visit some PCI members. Therefore, I assessed the relative importance of Eulonchus and other insect visitors to the pollination of a rare PCI species native to the Siskiyou Mountains, I. bracteata.

Methods. I quantified pollinator importance for all flower visitors at sites in northern California and southern Oregon as the product of average visit rate and …

Morphological Re-Description And Molecular Identification Of Tabanidae (Diptera) In East Africa, Claire M. Mugasa, Jandouwe Villinger, Joseph Gitau, Nelly Ndungu, Marc Ciosi, Daniel Masiga

All Peer-Reviewed Publications

Biting flies of the family Tabanidae are important vectors of human and animal diseases across continents. However, records of Africa tabanids are fragmentary and mostly cursory. To improve identification, documentation and description of Tabanidae in East Africa, a baseline survey for the identification and description of Tabanidae in three eastern African countries was conducted. Tabanids from various locations in Uganda (Wakiso District), Tanzania (Tarangire National Park) and Kenya (Shimba Hills National Reserve, Muhaka, Nguruman) were collected. In Uganda, octenol baited F-traps were used to target tabanids, while NG2G traps baited with cow urine and acetone were employed in Kenya and …

Endophytic Colonization Of Onions Induces Resistance Against Viruliferous Thrips And Virus Replication, Alexander Mutua Muvea, Sevgan Subramanian, Nguya Kalemba Maniania, Hans Michael Poehling, Sunday Ekesi, Rainer Meyhöfer

All Peer-Reviewed Publications

In agricultural ecosystems, insect pests, pathogens, weather patterns, and reduced soil fertility pose major challenges to crop productivity and are responsible for significant yield losses worldwide. Iris yellow spot virus (IYSV) vectored by Thrips tabaci Lindeman, is a major hindrance to onion production in eastern Africa. Control measures often rely on insecticides with deleterious effects. Endophytes are one key alternative as they can play important roles in mediating induced systemic resistance. Hence, we examined the potential effect of endophytic fungus Hypocrea lixii (F3ST1) on feeding and replication of IYSV on endophyte-colonized (E+) and endophyte-free (E-) onion plants. For more precise …

Lepidopteran Stem Borer Species Abundance And Associated Damages On Irrigated Kilombero Low Land Rice Ecosystem In Tanzania, Bonaventure January, Gration M. Rwegasira, Tadele Tefera

All Peer-Reviewed Publications

Background: Rice stem borers are among the most biotic stresses of economic importance in agriculture. Little was known about stem borer problem in Tanzania prior to this study. Understanding stem borer abundance and damages would help to design appropriate stem borer integrated pest management strategy in rice. This study was aimed at investigating rice stem borer’s species abundance and their associated damages in irrigated lowland rice ecosystem in Kilombero Tanzania. Materials and Methods: Field survey study on rice stem borer abundance and incidences were conducted in farmer’s fields on selected rice varieties at varied growth stages in Kilombero district under …

Physico-Chemical Properties Of Extruded Aquafeed Pellets Containing Black Soldier Fly (Hermetia Illucens) Larvae And Adult Cricket (Acheta Domesticus) Meals, F. G. Irungu, C. M. Mutungi, A. K. Faraj, H. Affognon, N. Kibet, C. Tanga, S. Ekesi, D. Nakimbugwe, K. K.M. Fiaboe

All Peer-Reviewed Publications

Fish farming is faced with the challenge of high cost of feeds because of the cost of high quality protein needed for formulation of the feeds. Thus, there is urgent need for alternative protein sources. The effects of substituting freshwater shrimp meal (FWSM) with black soldier fly larvae meal (BSFM) or adult cricket meal (ACM) on physico-chemical properties of hot-extruded fish feed pellets were investigated. The FWSM protein in a 26 g/100 g protein fish feed formulation was substituted at 0, 25, 50 and 75%, and moisture content of the formulated blends adjusted to 10, 20 or 30 g/100 g …

Fate Of Methoprene In Temperate Salt Marsh Ditches Following Aerial Applications, David J. Tonjes, Anne E. Mcelroy, Robin K. Barnes, Dominick V. Ninivaggi, Walter Dawydiak, Gregory T. Greene, Bruce J. Brownawell

Technology & Society Faculty Publications

Aerial applications of liquid methoprene are used in salt marshes to control mosquitoes by preventing adult emergence. Despite concern about toxicity to non-target organisms, little is known about environmental concentrations after applications, nor methoprene's persistence in salt marsh environments. Aqueous and sediment samples were collected from two marshes receiving weekly applications. Aqueous samples were collected as early as 30 minutes after applications and as long as nine days afterwards; sediment samples were taken within hours of application and as long as 19 days post-application. Use of time-of-flight liquid chromatography – mass spectral analysis allowed for ultra low detection limits (0.5 …

Diapause Disruption In Cirina Butyrospermi Vuillet (Lepidoptera, Attacidae), The Shea Caterpillar, In Burkina Faso, H. B. Bama, R. A. Dabire, D. Ouattara, S. Niassy, M. N. Ba, D. Dakouo

All Peer-Reviewed Publications

The shea caterpillar Cirina butyrospermi is an important insect, highly valued as a human food item in Burkina Faso. However, its appearance is seasonal due to its univoltine cycle. This study therefore investigated the possibilities of breaking the nymphal diapause by changing the environmental factors and through the hormonal treatment of prepupae and pupae using bovine insulin and 20-hydroxyecdysone. Changes in humidity and temperature did not result in emergence, suggesting a mandatory nature of the diapause in C. butyrospermi. Injection of 20-hydroxyecdysone between 20 and 40 ng on 20 C. butyrospermi pupae resulted in 15.24 and 47.5% emergence, respectively. The …

Effects Of Waste Stream Combinations From Brewing Industry On Performance Of Black Soldier Fly, Hermetia Illucens (Diptera: Stratiomyidae), Shaphan Y. Chia, Chrysantus M. Tanga, Isaac M. Osuga, Samira A. Mohamed, Fathiya M. Khamis, Daisy Salifu, Subramanian Sevgan, Komi K.M. Fiaboe, Saliou Niassy, Joop J.A. Van Loon, Marcel Dicke, Sunday Ekesi

All Peer-Reviewed Publications

Background: In recent years, there has been a rapidly growing demand for readily accessible substrates for mass production of Black Soldier Fly, Hermetia illucens Linnaeus. Beer production results in various by-products that typically end up in uncontrolled dumpsites constituting pollution problems, which merits urgent attention. The present study investigated whether the 12 formulated diets composed of brewers’ spent grains (BSGs), brewers’ yeast and cane molasses can serve as substrate for H. illucens production. Methods: Four different BSGs were selected and formulated into 12 diets, aiming at varying protein and net energy levels. The diets were offered to newly hatched (∼1 …

Push-Pull Farming System Controls Fall Armyworm: Lessons From Africa, Zeyaur R. Khan, Jimmy O. Pittchar, Charles A.O. Midega, John A. Pickett

All Peer-Reviewed Publications

Fall armyworm (FAW) Spodoptera frugiperda invaded Africa, with the first detections being reported in Central and Western Africa in early 2016, and now affects at least 40 countries in Africa, causing up to total crop loss amounting to over $6.2 billion p.a. FAW is an invasive polyphagous pest that causes damage to economically important crops and has recently been reported in the Indian sub-continent. Effective control of FAW through use of synthetic chemical pesticides and genetically modified crops such as Bt maize faces challenges including improper use, unaffordability by smallholder farmers and development of resistance by the pest. Additionally, dispersal …

Mitochondrial Dna Variation Of Feral Honey Bees (Apis Mellifera L.) From Utah (Usa), Allen Szalanski

Entomology and Plant Pathology Faculty Publications and Presentations

A study was conducted on the mitochondrial DNA genetic diversity of feral colonies and swarms of Apis mellifera from ten counties in Utah by sequencing the intergenic region of the cytochrome oxidase (COI-COII) gene region. A total of 20 haplotypes were found from 174 honey bee colony samples collected from 2008 to 2017. Samples belonged to the A (African) (48%); C (Eastern Europe) (43%); M (Western Europe) (4%); and O (Oriental) lineages (5%). Ten African A lineage haplotypes were observed with two unique to Utah among A lineage haplotypes recorded in the US. Haplotypes belonging to the A lineage were …