Agriculture Commons^™

Invasiveness Of An Exotic Gall Wasp Is Influenced By Interactions With Exotic And Endemic Organisms, Ignazio Graziosi

Theses and Dissertations--Entomology

American chestnut was once a crucial component of North American forests, but it was functionally eliminated by the introduction of the chestnut blight fungus. Chestnut is recently experiencing resurgence, but the introduced Asian chestnut gall wasp, a specialist herbivore, threatens chestnut recovery. I characterized this invasion and the interactions developing with host associates as the gall wasp spread in North America. Gall wasp dispersal is attributable to host plant distribution, effects of prevailing winds during adult insect emergence, and to topography. This knowledge may be useful to more accurately predict locations of future gall wasp infestations. Gall wasp invasiveness is …

Taxonomic And Molecular Studies In Cleridae And Hemiptera, John Moeller Leavengood Jr.

Theses and Dissertations--Entomology

Taxonomic changes are made based on checkered beetle (Coleoptera: Cleridae) types of the Natural History Museum, London (BMNH).Lectotypes are designated (and holotypes and paralectotypes recognized) for 44 species of Hydnocerinae, including the type species for Isolemidia, Parmius, Paupris, Allelidea, Blaesiopthalmus and Lemidia, four species of Enoclerus (Clerinae), and 14 species of Cymatodera (Tillinae). Annotations include comments on additional type material, new type locality, previous (type series) locality, and questionable or missing types. Phyllobaenus pallipes(Gorham) and P. rufithorax (Gorham) are synonymized with P. flavifemoratus(Gorham), P. chapini (Wolcott) is synonymized under P. lateralis (Gorham), and P. villosus (Schenkling) …

New Insights Into The Function And Development Of The Soldier Caste In Termites, Li Tian

Theses and Dissertations--Entomology

The evolution of nonreproductive castes is a defining characteristic of eusociality. The function and developmental regulation of the altruistic worker and soldier caste is the central element contributing to major advantages of eusociality over solitary animals. The soldier caste is the first evolved sterile caste in termites. Their primary function is believed to be colony defense. However, the function and development of termite soldiers remains largely unknown. Because of their apparent morphological adaptation for fighting and their limited behavior repertoire, our understanding of colony defense by termite soldiers is limited to their physical defense. In addition, we know little about …

A Comprehensive Understanding Of Corpse Management In Termites, Qian Sun

Theses and Dissertations--Entomology

Undertaking behavior is the disposal of dead individuals in social colonies to prevent potential pathogenic attack. This behavioral trait has convergently evolved in social insects (primarily termites, ants, and honeybee), and is considered an essential adaptation to social living. In honey bee and ants, workers recognize dead colony members through the postmortem change of chemical profile, and corpses are usually removed out of nest. However, in termites, little is known about the behavioral pattern, chemical cue or molecular basis. In the eastern subterranean termite, Reticulitermes flavipes, this study investigated undertaking behavior toward corpses of different origins and postmortem times. …

Mechanical Exclusion And Biological Control Strategies For The Invasive Brown Marmorated Stink Bug, Halyomorpha Halys (Hemiptera: Pentatomidae), Rachelyn Dobson

Theses and Dissertations--Entomology

The brown marmorated stink bug (Halyomorpha halys) is an invasive, agriculturally destructive pest present in most of the United States. Because organic farmers have few effective control options to combat this pest, three potential control options were investigated. Screens of different mesh sizes (0.42cm, 0.32cm, and 0.10cm) that covered vegetable crops were evaluated for their ability to exclude H. halys, allow the entry of beneficial insects, and protect the crop from various types of damage. H. halys and native stink bug egg masses were placed in an organic field and evidence of predation and parasitism from native …

Spatial And Temporal Dynamics Of Predator-Prey Interactions In Winter Wheat, Katelyn A. Kowles

Theses and Dissertations--Entomology

Aphids (Hemiptera: Aphididae) are pests of multiple cropping systems, primarily due to the viruses they vector and direct crop damage that is exacerbated by their rapid population growth. In Kentucky, grain aphids (Rhopalosiphum padi and Sitobion avenae) cause significant yield loss to winter wheat as vectors of Barley Yellow Dwarf virus (BYDV), prompting the routine application of insecticides. Coupled with increasing human populations and decreasing arable land, it is increasingly evident that biological control services provided by natural enemies represent a viable long-term management option. Aphids are preyed upon by a diverse array of predators that can be …

A Comparative Study Of Eastern And Western North American Populations Of Hippodamia Convergens (Coleoptera: Coccinellidae), Joshua S. Mccord

Theses and Dissertations--Entomology

Hippodamia convergens is a widely distributed insect predator in the United States and parts of Canada and Mexico. Several insectaries collect overwintering adults from aggregation sites in the Rocky Mountains during their winter dormancy. Collected beetles are then sold throughout the United States for augmentative biological control. This practice could have negative impacts on local populations of Hippodamia convergens in the Eastern United States. Intra-specific variation among H. convergens populations was examined for two characteristics of adults: photoperiodic induction of diapause and the presence of three known male-killing endosymbiont bacteria; Wolbachia, Spiroplasma, and Rickettsia. Four populations of H. …

A Revision Of The New World And Select Old World Species Of Cremnops Förster (Hymenoptera: Braconidae: Agathidinae), Erika M. Tucker

Theses and Dissertations--Entomology

Parasitoid wasps are an important group of organisms in need of systematic revision. This dissertation examines the cosmopolitan parasitoid wasp genus Cremnops. It is a compilation of three projects and significantly advances the taxonomic foundation of the genus.

The New World species of the genus Cremnops are revised. Thirty-three species of Cremnops are treated; five are described as new, i.e., C. bertae sp. nov., C. cluttsis sp. nov., C. nymphius sp. nov., C. wileycoyotius sp. nov. and C. witkopegasus sp. nov. Six species are synonymized, i.e., Cremnops caribensis Berta 1998, is synonymized under C. guanicanus Wolcott 1924; C. nigrosternum (Morrison …