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Biogeography and Natural History of Tiger Moths and Spongillaflies of Intermountain North America with Experimental Studies of Host Preference in the Lichen-Feeder <em>Cisthene angelus</em> (Insecta: Lepdioptera: Erebidae: Arctiinae and Neuroptera: Sisyridae)Fisher, Makani Layne 01 December 2018 (has links)
The Intermountain West is comprised of impressive land formations, numerous ecoregions, and a unique biota. The area has many flora and fauna that have been investigated, but the region is generally considered undersampled when it comes to insects. However, I propose the matter to be a lack of shared experience in identifying key insect species and the underutilization of professional and personal collections. These impediments are highlighted by two insect groups in the Intermountain West: spongillaflies and tiger moths. Spongillaflies can be difficult to recognize for the general entomologist and have rarely been recorded in the Intermountain West. My colleagues and I recently discovered a large population of spongillaflies in Utah that we present as a substantial additional record. I also followed the population throughout the 2016 field season to make natural history observations. I identified the spongillaflies to be Climacia californica and their associated host to be Ephydatia fluviatilis. During the season, a total of 1,731 specimens were collected, light traps were the most effective sampling technique and the population had one mass emergence event. I hope my work and figures will help investigators as they continue to search the area for spongillaflies. Tiger moths on the other hand have largely been collected in the Intermountain West and are easily recognized, generally being brightly colored. Because of these bright colors, they attract collectors and have been sampled heavily throughout the Intermountain West. However, until now, these records have not been utilized and tucked away in collections. We took the vast amount of records and used them to create predicted models of biogeography for each tiger moth species in the area. We successfully created species level ecological niche models (ENM) analyzing environmental variables such as temperature, precipitation, elevation, and vegetation. Overall, I found tiger moths can be collected almost everywhere and during each month of the year with 93 different species scattered across the region. I anticipate our ENM models to help researchers locate tiger moths of interest to investigate within the Intermountain West. During my studies, I investigated in detail the lichen feeding tiger moths (Lithosiini). Many tiger moths eat toxic plants, but only a few in the area consume lichen, an unusual host because of their secondary defensive chemicals. I investigated how these chemicals impacted Cisthene angelus caterpillars host selection by simultaneously offering them various lichens with differing chemistries. I expected these caterpillars to avoid usnic acid as it deterred other lichen feeding tiger moths. However, these caterpillars surprised me by consistently consuming the acid and being largely polyphagous. Our future work will be directed at how caterpillars balance nutritional needs and the chemicals they sequester.
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Moth Catching Masters: Analysis Of The Structrual And Mechanical Properties Of The Silk Spun By The Derived Orb-Web Weaver Cyrtarachne akiraiDiaz, Candido, Jr. 23 May 2018 (has links)
No description available.
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Identification of Gypsy Moth Defoliation in Ohio Using Landsat DataHurley, Angela Lorraine 31 July 2003 (has links)
No description available.
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Effects of x-rays on the free amino acid concentration of the hemolymph during the last larval instar of the wax moth, Galleria mellonella (L.) /Richardson, Barry Lovell January 1971 (has links)
No description available.
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Quantification and use of pheromone-baited milk-carton traps to monitor gypsy moth populationsCarter, Mark Robert 11 May 2006 (has links)
The goal of this research was to improve the understanding of the dynamics of male gypsy moth-pheromone trap interactions and the ecological factors that influence moth capture in pheromone traps. Defoliation, the most obvious expression of high density gypsy moth populations, may have a significant influence on gypsy moth population dynamics. This research focused on the use of defoliation and defoliation related processes to study moth capture in pheromone traps. Male moth wing length was found to decrease substantially only when defoliation exceeded a threshold level of ca. 40%, resulting in moths with either large or small wings. Moth wing length, determined from moths captured in intensively monitored traps, was found to accurately estimate whether or not defoliation exceeded ca. 40% in the vicinity of the trap. However, for traps serviced less intensively, male wing length provided a poor estimate of defoliation.
Larval development (using degree-days as a physiological measure of time) in sixteen plots was not altered as a result of varying levels of defoliation, but pupal phenology was significantly influenced by the level of defoliation . Despite distinct differences in pupal phenology, there were no differences in male moth capture over time in pheromone traps attributable to defoliation.
A broad relationship between the number of moths captured and egg mass density was developed. The spatial and temporal characteristics of gypsy moth populations were examined using a combination of field studies and defoliation maps. This information, in conjunction with data on wing length and the relationship between moths per trap and egg mass density, was used to develop an algorithm to interpret moth capture in pheromone traps to monitor gypsy moth populations. / Ph. D.
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Gypsy moth egg development: a model of phenological eventsGray, David Richard 01 February 2006 (has links)
A phenological model of gypsy moth egg development is proposed that distinguishes three phases of egg development, prediapause, diapause and postdiapause. A technique of measuring respiration rates of individual eggs was developed and respiration rate was used as a physiological variable to distinguish the phases. The pattern of respiration rate provided strong evidence in support of three distinct developmental phases. Respiration rate developed embryos declined sharply as prediapause was entered and rose sharply when diapause was completed. When the effect of age on respiration rate was removed, temperature had a uniform effect on respiration rate throughout the egg stage. A 10°C decrease in temperature caused an approximate 0.4 fold decrease in respiration rate, indicating that eggs in diapause are as equally responsive to temperature as egg in a nondiapause phase.
Developmental rate in prediapause was strongly temperature-dependent, and the relationship was described by a non-linear function. Prediapause duration was approximately 13 days at 31°C. The depletion of stored triglycerides was strongly linked to the completion of prediapause.
Developmental rate in postdiapause was found to be temperature- and age-dependent. Developmental response to temperature was relatively weak and linear at the onset of postdiapause. As postdiapause advanced, the response became stronger and non-linear. The temperature- and age-dependent developmental response was fully described by the temperature-dependent developmental response at the onset of postdiapause, and by a temperature-dependent rate change parameter. / Ph. D.
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Short-term effects of defoliation by gypsy moth larvae on Appalachian headwater streams in VirginiaMarshall, Brett Douglas 02 May 2009 (has links)
This field study investigated the short-term effects of riparian defoliation by gypsy moth larvae on three aspects of headwater stream ecology, water quality, benthic macroinvertebrate community structure, and benthic macroinvertebrate function (expressed as secondary production). The experimental design was to compare measurements in three streams that were extensively defoliated by gypsy moth larvae (defoliated treatment), with three streams that were not affected by gypsy moth larvae (reference treatment). Although the riparian canopy became much more open after defoliation, I observed no significant differences in any water quality parameters except temperature, which was slightly elevated for a brief period after defoliation. There was a significant increase in the amount of detritus (frass and orts) falling into defoliated streams in the spring, which was followed by a significant decrease in the of amount detritus falling into defoliated streams in autumn. Many measures of community structure were analyzed, but only the Index of Biotic Similarity demonstrated a significant difference, indicating that, at most, only slight changes in community structure occurred. Secondary production of two representative aquatic insects, Peltoperlidae (shredder) and Diplectrona modesta (collectorfilterer), was not affected by defoliation. Glossosoma nigrior (scraper) achieved higher production because of a second-generation being induced by elevated temperature. I conclude that the short-term effects of riparian defoliation by gypsy moth larvae were minor. / Master of Science
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Egg mass sampling plans for gypsy moth management programsCarter, Jane Louise 10 June 2009 (has links)
The goal of this research was to develop gypsy moth egg mass sampling plans that reflect the influence of habitat, changes in egg mass distribution, and provide populations densities or density categories for making control decisions.
Sequential egg mass sampling plans for gypsy moth management programs in urban and suburban habitats were developed from 0.01 ha fixed-radius plot samples collected in Loudoun, Fairfax, and Arlington Counties, Virginia. The sampling plans were develop from Wald's sequential probability ratio test and is based on a negative binomial distribution. Operating characteristic and average sample number curves were used to determine the acceptability of the sampling plans. Three sampling plans were developed for the action thresholds of 618, 1,236, and 2,471 egg masses/ha.
The use of binomial sampling for low density (<618 egg masses/ha) gypsy moth populations in continuously forested habitats was examined. Fixed- and variable-radius plot egg mass samples were collected in 28 study areas in Virginia, Maryland, and Massachusetts. The relationship between egg mass density and the proportion of trees with zero egg masses was developed. Binomial sampling resulted in a higher relative variability and lower relative efficiency than the fixed- and variable-radius plot sampling method. Binomial sampling was determined not to be an effective sampling method for gypsy moth populations below 618 egg masses/ha.
Fixed- and variable-radius plot egg mass samples were taken when leaves were present (summer) and absent (winter) in 136 sample sites in Virginia. A significant difference between summer and winter counts was determined. The relationship between summer and winter counts was quantified using nonparametric Statistics. Winter egg mass counts were found to be 14 to 34 percent higher than summer egg mass counts . The probability of a summer egg mass count exceeding an action threshold was constructed by fitting a logistic curve to empirical data for the action thresholds of 618 and 1,236 egg masses/ha. Egg mass counts need to compensate for differences between summer and winter counts. Alternatively, the probability of a summer egg mass count exceeding an action threshold should be utilized. / Master of Science
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Amplified fragment length polymorphism (AFLP) analysis of genetic variability in PhalaenopsisChang, Yeun-Kyung 28 August 2008 (has links)
Amplified fragment length polymorphism (AFLP) markers allow a rapid assessment of the level of genetic variation that would be difficult to evaluate using a limited number of morphological markers. AFLP was used to assess the level of genetic variation among 16 different Phalaenopsis species and hybrids. Ten AFLP primer combinations were used for genetic analysis of these Phalaenopsis and 95% of polymorphism in 16 Phalaenopsis species and hybrids was detected. The genetic similarity among Phalaenopsis species and hybrids ranged from 0.298 to 0.774 based on Dice coefficient. The dendrogram derived by UPGMA analysis clustered into two main groups. A significant linear relationship (r² = 0.524, P < 0.0001) was observed between known pedigrees and AFLP-derived genetic similarity for 136 pairwise comparisons of Phalaenopsis species and hybrids. The results indicate that there is an abundance of genetic diversity among within Phalaenopsis and that AFLP can be used to distinguish morphologically similar genotypes.
In a second study, the effect of gametophytic selection on genetic diversity in Phalaenopsis was examined by AFLP analysis. Sixteen F1 seedlings resulting from cross-pollination that occurred within high (30 ºC) and low (14 ºC) temperature incubators between two hybrid Phalaenopsis [P. (Taisoco Windian à Sogo Yukidian) by P. hybrid unknown], were subjected to genetic analysis by AFLP. A total of 651 fragments ranging in size from 100 to 350 bp were detected using six primer combinations, of which 387 (59.4%) were polymorphic. Seedlings derived from different temperature treatments exhibited 25.5% to 35.9% polymorphism. The genetic similarity among 16 F1 seedlings ranged from 0.825 to 0.946 based on the Dice coefficient. A dendrogram based on 387 polymorphic markers was derived by UPGMA analysis resulting in three major groups and one subgroup. The dendrogram analysis showed clear clustering in Phalaenopsis hybrids pollinated under different temperature treatments, suggesting that several loci may have been selected during the divergent temperature stress treatments during pollination and early pollen tube growth. / Master of Science
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Spatial and temporal distribution of false codling moth across landscapes in the Citrusdal area (Western Cape Province, South Africa).Stotter, Robert L. 03 1900 (has links)
Thesis (MScAgric (Conservation Ecology and Entomology)--University of Stellenbosch, 2009. / The false codling moth (FCM), Thaumatotibia leucotreta (Meyrick)
(Lepidoptera: Tortricidae), is an indigenous pest of citrus fruit in southern Africa, and is a
pest of high phytosanitary concern, impacting negatively on the export of fresh citrus
fruit from South Africa to some international markets. FCM is a particularly serious pest
in the Citrusdal area in the Western Cape Province of South Africa. FCM is known to
infest most types of citrus, with navel oranges being particularly prone to attack, whereas
lemons are not considered to be a favoured host. Conventional control strategies that rely
on the use of insecticides are of limited use due to high levels of insecticide resistance in
FCM populations. Mating disruption, the Sterile Insect Technique (SIT) and the
integration of different control techniques are options that are currently being adopted.
Little is known about FCM host preferences in this geographical area, or about its
dispersal capacity. The ability of FCM to migrate between various host patches,
including citrus orchards and indigenous fynbos vegetation, and its ability to maintain a
viable population in alternative host plants when there is no fruit available for infestation
in citrus orchards has not been well studied. Knowledge of these largely behavioural
facets is important in planning an effective control strategy for FCM.
Towards addressing this dearth of knowledge, FCM pheromone traps were set out in
transects in the Citrusdal area. These transects included citrus orchards, and extended
beyond citrus orchards, to include a range of habitat types and elevational gradients. This
provided a grid to assess the spatial and temporal distribution of male FCM in the area.
In addition, intensive sampling and inspection of potential host plant material was
undertaken in the area in an attempt to identify any alternative host plants.
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