<p> Adaptive phenotypic plasticity is a key mechanism by which organisms deal with variation in many different aspects of their environment. Adaptive plasticity can occur in any trait, from aspects of biochemistry and morphology to behaviors. Because so many different traits can be plastic, organisms often respond plastically to a given change in their environment, such as an increase in temperature, with adaptive changes in multiple traits. Nevertheless, how these different plastic responses interact with each other and evolve together has received little attention. My research addresses these potential interactions among plastic traits and proposes new hypotheses regarding the causes and consequences of these interactions. It does so by focusing on heat avoidance in the caterpillars of <i>Battus philenor</i> (the pipevine swallowtail) which involves two distinct plastic mechanisms. First, the caterpillars can change color when they molt, a form of morphological plasticity in which they develop a red color under high temperatures which cools them by absorbing less solar radiation. Second, when the caterpillars become too hot, they will leave their host to seek cooler thermal refuges, a case of behavior as a form of plasticity. In terms of function, I demonstrated through field research that these two responses to high temperatures are largely redundant. Behavior provides a much stronger and faster response than color change, and red coloration provides little additional cooling when on a refuge. Instead, the primary benefit of color change is that it reduces the use of refuge seeking behavior, allowing the caterpillars to stay on their hosts longer. Using laboratory experiments, I demonstrated that this change in the use of refuge-seeking behavior with color occurs because color changes the cue for the behavior, body temperature, rather having any effect on how the caterpillar responds to that cue. Alternatively, similar experiments on caterpillars of varying sizes show that developmental size change lowers the body temperature at which caterpillars leave their host, demonstrating a change in the response to the cue (although larger caterpillars are also warmer, so both mechanisms are likely relevant for how size changes the expression of behavior). All of my research to this point was conducted on the local population in southern Arizona, which experiences quite high temperatures, but <i>B. philenor</i> is also found in much cooler environments, such as the Appalachian Mountains. Given this variation in their thermal environment, I used common garden experiments to compare the capacity for color change and refuge-seeking among B. philenor caterpillars from across the species range. Both color change and refuge seeking not only occurred in all populations, but also had the same reaction norms, occurring at the same temperatures and to the same degree. This is particularly notable for color change, which is not observed in the wild in northeastern populations, and thus has persisted despite minimal if any use. Overall, I have shown that studies of plasticity need to account for plasticity in different traits as well as the interactions between these forms of plasticity. My research on B. philenor provides a model for how to address these interactions, which future research can extend to additional organisms and environmental circumstances. </p>

acase@tulane.edu

The purpose of this project was to evaluate diflubenzuron ovicidal effects on adult female alfalfa weevils " Hypera postica in the laboratory. There was little relationship of weevil mortality to dosage or length of exposure of the adult to the chemical. An indirect result of diflubenzuron was an increase in muscardine fungus (Beauveria Sp.). Other effects of the chemical on the adults were yellow deposits and tissue extending from the tip of the abdomen. The main effect of dilfubenzuron when fed to female alfalfa weevils was on the eggs. The effects were dosage related, especially on eggs viability. The viability was dropped from 99% in the control to 38.9% on the treated insects in ten days using the highest dosage. Another effect of diflubenzuron on alfalfa weevil eggs was on the shape of the eggs. The treated insects laid longer and lighter color eggs.

acase@tulane.edu

Thesis (Ph.D.)--Indiana University, Dept. of Biology, 2006. / Source: Dissertation Abstracts International, Volume: 67-01, Section: B, page: 0048. Adviser: James D. Bever. "Title from dissertation home page (viewed Feb. 9, 2007)."

<p>This thesis deals with the synthesis of conjugated dienicand trienic pheromone components- C₁₂-C₁₆alcohols, acetates and aldehydes and theirapplications in pheromone communication studies.</p><p>Insect pheromones are widely used in modern pest management.The development of effective tools for plant protection is aresult of complex broad, interdisciplinary basic and appliedresearch. A practical use of pheromones for pest managementusually requires that specific active chemicals must beisolated,identified and produced synthetically. The creationof pheromone materials besides requires the identification ofthe active components, determination of the roles of otherpossible isomers or degradation products, the design ofdispensers of suitable substrates and evaporationparameters.</p><p><b>The aim of the thesis</b>was critically to survey methods for the syntheses ofconjugated polyenic compounds and to focus to the synthesis ofseveral conjugated polyenic pheromone components providingsufficient quantities of chemically and isomerically purecompounds for bioassaying.</p><p><b>The principal objective of the thesis</b>was concerned withthe further aim of developing effective synthetic materials forplant protection. The work was focussed:</p><p>=>To identify the compoundscollected from the leafminer moth<i>Phyllonorycter emberizaepenella</i>(Lepidoptera:Gracillaridae) and perform a detailed identification of thepheromones of the Brazilian apple leafroller<i>Bonagota cranaodes</i>(Meyrick) (Lepidoptera: Tortricidae)and of the codling moth<i>Cydia pomonella</i>(L.) (Lepidoptera: Tortricidae). =>Tostudy the effect of non-pheromonal isomers of the mainpheromone component on the sex attraction of B. cranaodes andC.<i>pomonella</i>in wind tunnel and field tests.=>To study the role of identified pheromonecomponents in the pheromone communication of the currant shootborer Lampronia capitella (Cl.) (Lepidoptera: Prodoxidae), andto design and optimize the dispenser for effective trapping.=>To investigate the presence of sex pheromonecomponents in the tobacco hawk moth<i>Manduca sexta</i>(L.) (Lepidoptera: Sphingidae).</p><p>The syntheses of four geometrical isomers of3,5-dodecadienyl acetate; (10E,12E,14Z)- and(10E,12E,14E)-(10,12,14)-hexadecatrien-1-als;(E,Z)-, (Z,E)-,and (Z,Z)-8,10-dodecadienol, codlemone acetate and aldehyde;(9Z,11Z)-9,11-tetradecadienol, corresponding acetate andaldehyde; all geometrical isomers of 8,10-and10,12-tetradecadienols and corresponding acetates wereperformed to ensure all these bioassays with syntheticpheromone components. All compounds were made in high chemicaland stereochemical purity, most of them more than 99%isomerically pure or by using several separation andpurification techniques.</p><p>The suitable synthetic schemes for the synthesis of all fourgeometrical isomers of four conjugated dienic pheromonecomponents are presented in this thesis.</p><p>The reactions and purification methods used here exemplifythe wide range of possibilities realized for such syntheses:they present the successful application of many syntheticmethods. The importance of this synthetic work is that thecompounds synthesized are not commercially available or on theother hand the purity of the purchasable compounds is notsatisfactory for research in the field of chemical ecology.</p><p><b>Key words:</b>Lepidoptera, sex pheromone, pheromonedispenser, 3,5-dodecadienyl acetate, 10,12,14-hexadecatrienal,8,10-dodecadienol, codlemone atsetate, codlemone aldehyde,8,10- tetradecadienol, 8,10-tetradecadienyl acetate,10,12-tetradecadienol, 10,12-tetradecadienyl acetate,<i>Lampronia capitella, Manduca sexta, Bonagota cranaodes,Cydia pomonella, Phyllonorycter emberizaepenella</i>,conjugated polyenic pheromone, conjugated diene, MPLC,(9Z,11Z)-9,11-tetradecadien-1-ol,(9Z,11Z)-9,11-tetradecadien-1-al</p>

The fungus Verticillium lecanii was assessed for entomopathogenicity against nymphal Bemisia tabaci in an environmental chamber and in a greenhouse mist chamber on the host Euphorbia pulcherima. Proportional mortality of Bemisia nymphs due to fungal exposure were; in the environmental chamber 89-96%, and in the mist chamber 61-89%. Two fungal characteristics, hyphae growth and sporulation, were used as parameters for augmentation experiments. Response to particular honeydew constituents, glutamine, glutamic acid, serine and sucrose in concentrations ranging 500-40,000 ppm were measured. Hyphae growth, in comparison to water agar (1.26-1.52 mm/24 h), was inhibited by all substrates at all concentrations (0.82-1.47 mm/24 h). Sporulation was enhanced at higher concentrations, 17.0-117.0 (x10⁴) spores produced, in comparison with water agar, 10.2-15.5 (x10⁴) spores produced.

Female insects produce eggs that are nutrient-rich. For most Lepidoptera, protein is acquired during larval feeding. Insects use pre-ingestive, post-ingestive and developmental strategies to meet nutritional needs. In this dissertation I examine the importance of these strategies to females of two related lepidopteran species differing in their adult feeding. Adult Heliothis virescens (Family Noctuidae) ingests nectar. The sexes were not distinguished according to their selective feeding behavior, but females accumulated more protein and carbohydrate. When restricted to diets, females ate and accumulated more protein on high protein diets. There were no sexual differences on high carbohydrate diets. Results indicate that female H. virescens larvae accumulate protein by regulating both intake and post-ingestive processing on high protein foods. Adult Estigmene acrea (Family Arctiidae) do not feed. The sexes did not differ in their selective feeding behavior. When restricted to diets, female E. acrea increased ingestion of diets unbalanced in protein and carbohydrate leading to greater intake of both nutrients but only accumulated more protein. Lastly, E. acrea prolong juvenile development if too small at later stages effectively extending their period of ingestion and processing. As previously shown protein-derived growth in female H. virescens progressively increased as dietary protein levels increased. Storage protein, a component of protein-derived growth, was found to similarly increase but was more abundant in females across all pupal stages and diets. Pharate adults retained a portion of total storage protein with females retaining greater levels presumably toward egg provisioning. Growth of both H. virescens and E. acrea was highly clustered compared to ingestion values suggesting post-ingestive processing of nutrients to regulate growth. Males and females of both species efficiently utilized carbohydrate except at high ingestion. Females of both species utilized nitrogen more efficiently than did males at all ingestion levels, contributing to their greater protein accumulation. The manner of post-ingestive processing by these two species reflects differences in their larval diet. Clearly, my studies show that female caterpillars regulate both nutrient consumption and post-ingestive physiology to accumulate greater reserves.

The birch leaf-mining sawfly, Fenusa pusilla (Lep.), has been a major pest of birch trees in Canada since its introduction into North America in 1923 (Britton, 1924a, 1924b). From that date onwards, serious infestations of leaves of most species of birch have been reported, particularly from the maritime provinces. The species was first noted in the province of Quebec in 1929 by Dr. Lionel Daviault of Quebec City (Daviault, 1937) who observed it developing on seven birch species at Berthier. [...]

The determination of dietary habits by examination of fresh stomach, intestinal or faecal material is widely used in vertebrate and invertebrate ecology. Generally speaking, most fresh faecal studies depend upon microscopic determinations of the ingested material. One of the more recent applications includes microscopic studies of the grazing habits of sheep. [...]