Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1992. / Vita. Abstract. Includes bibliographical references (leaf 68). Also available via the Internet.

Thesis (Ph. D. in Biological Sciences)--Vanderbilt University, May 2009. / Title from title screen. Includes bibliographical references.

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

Belonging to the diverse order Araneae, the black widow spider Latrodectus 4 hesperus produces high-performance silks with a broad range ofbiological functions and mechanical properties. The cob weaver spider spins different fibers by using seven specialized glands located in its abdomen. Egg case silk originates from the tubuliforrn gland and to date, no proteins that participate in the assembly process of egg case silk proteins have been identified. The goal of this project was the expression, purification, and characterization of such protein products. De novo sequencing of peptides from in-solution tryptic digestion of black widow spider dragline silk, the most studied type of silk, identified a novel cysteine-rich nonfibroin- like peptide that we named cysteine-rich component or CRC- 1. Further analysis of a large pool of nucleic acid sequences deposited in our custom eDNA database revealed 4 additional sequences with similarities to each other at the amino acid level called CRC-2, CRC-3, CRC-4, and CRC-5, suggesting a new family of proteins. Specifically, Q-PCR analysis revealed that the CRC-5 mRNAs were predominantly expressed in the tubuliform and aggregate glands. Since the aggregate gland manufactures a more complex aqueous solution compared to the tubuliforrn gland, we focused these studies on the tubuliform gland and resultant egg case fibers. Westem blot analysis using a cross-reactive polyclonal anti-CRC-1 antiserum conoborated the presence of CRC-5 in the tubulifmm gland and egg case silk, supporting the colocalization ofTuSpl, a tubuliform gland-specific protein, and CRC-5. Thus, we have demonstrated that these two proteins are present within tubuliform silks. In vitro studies suggested that recombinant CRC-5 displayed enzymatic activity similar to a sulfhydryl oxidase. Collectively, our findings provide new insights into novel proteins that have a potential role in the silk assembly and extrusion pathway of egg case silk fibers.