227,703 research outputs found

    An Assessment of Gypsy Moth Eradication Attempts in Michigan (Lepidoptera: Lymantriidae)

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    Michigan\u27s infestation of gypsy moth, Lymantria dispar, extends over 600,000 acres, First discovered in Michigan in the 19505, gypsy moth was reportedly eradicated through the use of DDT then reintroduced in the 1970s, Substantial circumstantial biological evidence, however, points to the probability that gypsy moth has resided continuously in Michigan for over 30 years, Environmental factors may be largely responsible for containing Michigan\u27s gypsy moth popUlations

    The Impact of Prescribed Fire on Moth Assemblages in the Boston Mountains and Ozark Highlands, in Arkansas

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    In addition to the impacts of prescribed fires on forest vegetation, this ecosystem process also has dramatic impacts on associated insect assemblages. For herbivorous, terrestrial insects, fire predictably results in a cycle of initial insect population reduction followed by recovery and growth, in which these insect populations exceed pre-fire abundances. We sought to examine if fire-induced disturbance cycles make prescribed burned areas more or less suitable specifically for moths (order Lepidoptera), which is a major food source for, among others, multiple bat species. We surveyed moth assemblages at 20 burned and 20 unburned sites in the Boston Mountain and Ozark Highland ecoregions of Arkansas, to determine if biomass or abundance of moths differed between areas that had been burned in the past 10 years, and those areas that had never been burned. Samples were collected early (April to July) and late (August to November) in the growing season of 2017 (hereafter early season and late season, respectively). We compared biomass and abundance of all moths, and of five representative moth species, between burned and unburned sites. The five moth species were chosen and considered to be representative due to their high relative abundance, and ease of identification. The five chosen moth species included the banded tussock moth (Halysidota tessellaris), white-dotted prominent moth (Nadata gibbosa), ailanthus moth (Atteva aurea), grape leaffolder (Desmia funeralis), and painted lichen moth (Hypoprepia fucosa). Results from paired t-tests showed no significant difference in total biomass, or abundance of representative species between burned and unburned sites. However, generalized linear regression models showed significantly higher abundance of moths in areas with high basal area that had been previously burned (β = -0.038 ± 0.004 SE,

    Optimization of moth-eye antireflection schemes for silicon solar cells

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    Nanostructured moth-eye antireflection schemes for silicon solar cells are simulated using rigorous coupled wave analysis and compared to traditional thin film coatings. The design of the moth-eye arrays is optimized for application to a laboratory cell (air–silicon interface) and an encapsulated cell (EVA-silicon interface), and the optimization accounts for the solar spectrum incident on the silicon interface in both cells, and the spectral response of both types of cell. The optimized moth-eye designs are predicted to outperform an optimized double layer thin film coating by approximately 2% for the laboratory cell and approximately 3% for the encapsulated cell. The predicted performance of the silicon moth-eye under encapsulation is particularly remarkable as it exhibits losses of only 0.6% compared to an ideal AR surfac

    Gypsy Moth (Lepidoptera: Lymantriidae): History of Eradication Efforts in Michigan, 1954-1981

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    Gypsy moth, Lymantria dispar, was first discovered in Michigan in 1954, Aerial spraying operations were conducted to eradicate gypsy moth infestations with synthetic insecticides (DDT, carbaryl, and diflubenzuron)

    Garden and landscape-scale correlates of moths of differing conservation status: significant effects of urbanization and habitat diversity

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    Moths are abundant and ubiquitous in vegetated terrestrial environments and are pollinators, important herbivores of wild plants, and food for birds, bats and rodents. In recent years, many once abundant and widespread species have shown sharp declines that have been cited by some as indicative of a widespread insect biodiversity crisis. Likely causes of these declines include agricultural intensification, light pollution, climate change, and urbanization; however, the real underlying cause(s) is still open to conjecture. We used data collected from the citizen science Garden Moth Scheme (GMS) to explore the spatial association between the abundance of 195 widespread British species of moth, and garden habitat and landscape features, to see if spatial habitat and landscape associations varied for species of differing conservation status. We found that associations with habitat and landscape composition were species-specific, but that there were consistent trends in species richness and total moth abundance. Gardens with more diverse and extensive microhabitats were associated with higher species richness and moth abundance; gardens near to the coast were associated with higher richness and moth abundance; and gardens in more urbanized locations were associated with lower species richness and moth abundance. The same trends were also found for species classified as increasing, declining and vulnerable under IUCN (World Conservation Union) criteria

    Field Tests of Kairomones to Increase Parasitism of Spruce Budworm (Lepidoptera: Tortricidae) Eggs by \u3ci\u3eTrichogramma\u3c/i\u3e Spp. (Hymenoptera: Trichogrammatidae)

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    Hexane extracts of spruce budworm, Choristoneura fumiferana, moth scales, applied at 0.04 moth-gram equivalents/branch and at 0.06 moth-gram equivalents/tree, failed to increase parasitism rates of Trichogramma spp. in two cutover spruce-fir stands in Maine. Releasing Maine-strain T. minutum apparently increased parasitism rates about 20-fold. However, application of kairomone extracts to whole branches and to upper crowns of small trees may have interfered with host-searching behaviors of Trichogramma parasitoids

    Expansion of the winter moth outbreak range : no restrictive effects of competition with the resident autumnal moth

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    1. Both direct and indirect competition can have profound effects on species abundance and expansion rates, especially for a species trying to strengthen a foothold in new areas, such as the winter moth (Operophtera brumata) currently in northernmost Finland. There, winter moths have overlapping outbreak ranges with autumnal moths (Epirrita autumnata), who also share the same host, the mountain birch (Betula pubescens ssp. czerepanovii). Competitive interactions are also possible, but so far unstudied, are explanations for the observed 1–3 years phase lag between the population cycles of the two moth species. 2. In two field experiments, we studied host plant-mediated indirect inter-specific competition and direct interference/exploitation competition between autumnal and winter moths. The experimental larvae were grown either with the competing species or with the same number of conspecifics until pupation. Inter-specific competition was judged from differences in pupal mass (reflecting lifespan fecundity), larval development time and larval survival. 3. Larval performance measurements suggested that neither direct nor indirect interspecific competition with the autumnal moth reduce the growth rate of winter moth populations. Winter moths even had a higher probability of survival when reared together with autumnal moths. 4. Thus, we conclude that neither direct nor indirect inter-specific competition is capable of suppressing the spread of the winter moth outbreak range and that both are also an unlikely cause for the phase lag between the phase-locked population cycles of the two moth species

    Odour perception in the codling moth Cydia pomonella L.

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    The codling moth, Cydia pomonella L. (Lepidoptera: Tortricidae) is a renowned pest in apple, pear and walnut orchards, and its activities are in large guided by volatile odours as sensory cues. This thesis spans over a large part of the olfactory chain of events in the codling moth, from brain to behaviour. The main emphasis was placed on the detection of plant odours, and some of the works presented are novel to codling moth research. The volatiles emitted by host-plant species were analysed, revealing variations in the odour profiles both between species of host plants and at different phenological stages of a host plant, which indicates that females are flexible in their behavioural response to host odours. A first step was taken to map the antennal olfactory receptor neurons and their specificity, where several behaviourally active compounds were found to be detected by neurons housed in sensilla auricillica, one of the morphological types of sensilla found on the antenna of the moth. In a study of the antennal lobe, the primary integration centre for odour processing in the insect brain, we describe the three dimensional structure of the array of olfactory glomeruli of both sexes. Behavioural experiments show that both males and females are attracted to plant odours, and that host recognition in codling moths are encoded not by single compounds but by a blend of volatiles. Taken together, the results presented in this thesis provide new insights into moth olfaction and odour-dependent behaviour in general, and into that of the codling moth in particular

    Relationship Between Fruit Yield and Damage by Codling Moth and Plum Curculio in a Biologically-Managed Apple Orchard

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    Fruit yield, codling moth (Cydia pomonella) damage, and plum curculio (Conotrachelus nenuphar) damage were monitored over an 8-year period in a O.5-ha, biologically-managed apple orchard in southwestern Michigan. The relationship between yield and damage was examined for both of these pests. The orchard showed clear biennial bearing patterns of alternating high and low yields. A significant negative correlation was found for yield and percent- age damage by codling moth but not for plum curculio damage. However, the estimated amount of fruit damaged by codling moth remained relatively stable over the period, indicating that changes in percentage damage depended on yield dynamics rather than changes in codling moth abundance. In contrast, the amount of fruit damaged by plum curculio showed biennial fluctuations and a positive correlation with yield, indicating that the population of this pest was capable of responding with increased oviposition in years with greater fruit yield. In addition, a comparison of codling moth fruit injury in years with and without the use of pheromone mating disruption showed no statistically significant reduction in damage as a result of using this method, suggesting that the orchard may be too small or codling moth populations too high for effective use of this management tactic

    Field observations about the behaviour of codling-moth in Trentino (North-Eastern Italy)

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    Codling-moth and applescab are the most important pathogens in both conventional and organic apple productions. In order to control any phytopathological problem, it is important to improve the knowledge of the behaviour of each specific pest. Since several years (starting from 1986) we are improving in Trentino (North-Eastern Italy) the observations of the population dynamics of codling-moth in order to find the best way to control and treat this pest insect. Constant monitoring and the knowledge of the characteristics of the different compounds and possible methods to control the codling-moth (mating disruption, granulose virus and specific nematodes) represent the most important basis to organize an effective controlstrategy
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