Annual Survey of Virginia Law: Professional Responsibility

On October 18, 1996, the Virginia State Bar Council (Council) approved a change in the format of the Code of Professional Responsibility (Code) from canons, disciplinary rules, and ethical considerations to the Model Rules of the American Bar Association (Model Rules). The first twenty-one rules, Model Rules 1.1 through 2.5, were approved in substance with some amendments at the Council\u27s meeting on June 19, 1997. This approval represents approximately one-third of the conversion from the Code to the Model Rules. The second installment of the conversion was approved by Council at its October 1997 meeting. Notwithstanding Council\u27s approval of this major undertaking, the adoption of the Model Rules will require the imprimatur of the Supreme Court of Virginia

Conifer Responses to a Stylet-Feeding Invasive Herbivore and Induction with Methyl Jasmonate: Impact on the Expression of Induced Defenses and a Native Folivore

Trees attacked by multiple herbivores need to defend themselves against dynamic biotic challenges; appropriate responses to one stressor can elicit hormonal responses that are antagonistic to another. Hemlock (Tsuga canadensis) infestation by hemlock woolly adelgid (HWA; Adelges tsugae) results in the accumulation of the defensive hormone salicylic acid. We explored the potential for HWA infestation to interfere with anti‐folivore‐induced defence signalling and its implications for a native folivore (hemlock looper; Lambdina fiscellaria). Hemlocks were infested with HWA and/or sprayed with methyl jasmonate; foliar defences were analyzed and foliage quality for looper larvae was assessed. Both treatments activated foliar defensive traits, including a HWA‐mediated increase in peroxidase activity and an accumulation of cell wall‐bound phenolics and lignin, as well as a methyl jasmonate‐mediated increase in lipoxygenase activity. The two treatments had an additive effect on other defensive traits and both treatments negatively affected looper performance. These results suggest that salicylic acid and jasmonic acid are not strictly antagonistic in conifers and that both have a role in anti‐folivore defence signalling. The present study illustrates the need for a better understanding of hormone signalling, cross‐talk and induced responses in conifers

A Four-Year, Seven-State Reforestation Trial with Eastern Hemlocks (\u3cem\u3eTsuga canadensis\u3c/em\u3e) Resistant to Hemlock Woolly Adelgid (\u3cem\u3eAdelges tsugae\u3c/em\u3e)

We conducted over a decade of research into individual eastern hemlock (Tsuga canadensis; hemlock) trees that are potentially resistant to hemlock woolly adelgid (Adelges tsugae; HWA), an invasive xylem-feeding insect that is capable of rapidly killing even mature trees. Following clonal propagation of these individuals, in 2015 we planted size- and age-matched HWA-resistant and HWA-susceptible hemlocks in HWA-infested forest plots in seven states. In 2019, we re-surveyed the plots; 96% of HWA-resistant hemlocks survived compared to 48% of susceptible trees. The surviving HWA-resistant trees were also taller, produced more lateral growth, retained more foliage, and supported lower densities of the elongate hemlock scale Fiorinia externa, another invasive hemlock pest, than the surviving HWA-susceptible trees. Our results suggest that HWA management may benefit from additional research exploring the identification, characterization, and use of HWA-resistant eastern hemlocks in future reforestation efforts

Chronic impacts of invasive herbivores on a foundational forest species: a whole‐tree perspective

Forests make up a large portion of terrestrial plant biomass, and the long‐lived woody plants that dominate them possess an array of traits that deter consumption by forest pests. Although often extremely effective against native consumers, invasive species that avoid or overcome these defenses can wreak havoc on trees and surrounding ecosystems. This is especially true when multiple invasive species co‐occur, since interactions between invasive herbivores may yield non‐additive effects on the host. While the threat posed by invasive forest pests is well known, long‐term field experiments are necessary to explore these consumer‐host interactions at appropriate spatial and temporal scales. Moreover, it is important to measure multiple variables to get a “whole‐plant” picture of their combined impact. We report the results of a 4‐yr field experiment addressing the individual and combined impacts of two invasive herbivores, the hemlock woolly adelgid (Adelges tsugae) and elongate hemlock scale (Fiorinia externa), on native eastern hemlock (Tsuga canadensis) in southern New England. In 2011, we planted 200 hemlock saplings into a temperate forest understory and experimentally manipulated the presence/absence of both herbivore species; in 2015, we harvested the 88 remaining saplings and assessed plant physiology, growth, and resource allocation. Adelgids strongly affected hemlock growth: infested saplings had lower above/belowground biomass ratios, more needle loss, and produced fewer new needles than control saplings. Hemlock scale did not alter plant biomass allocation or growth, and its co‐occurrence did not alter the impact of adelgid. While both adelgid and scale impacted the concentrations of primary metabolites, adelgid effects were more pronounced. Adelgid feeding simultaneously increased free amino acids local to feeding sites and a ~30% reduction in starch. The cumulative impact of adelgid‐induced needle loss, manipulation of nitrogen pools, and the loss of stored resources likely accelerates host decline through disruption of homeostatic source‐sink dynamics occurring at the whole‐plant level. Our research stresses the importance of considering long‐term impacts to predict how plants will cope with contemporary pressures experienced in disturbed forests

Pretty Picky for a Generalist: Impacts of Toxicity and Nutritional Quality on Mantid Prey Processing

Prey have evolved a number of defenses against predation, and predators have developed means of countering these protective measures. Although caterpillars of the monarch butterfly, Danaus plexippus L., are defended by cardenolides sequestered from their host plants, the Chinese mantid Tenodera sinensis Saussure guts the caterpillar before consuming the rest of the body. We hypothesized that this gutting behavior might be driven by the heterogeneous quality of prey tissue with respect to toxicity and/or nutrients. We conducted behavioral trials in which mantids were offered cardenolide-containing and cardenolide-free D. plexippus caterpillars and butterflies. In addition, we fed mantids starved and unstarved D. plexippus caterpillars from each cardenolide treatment and nontoxic Ostrinia nubilalis Hübner caterpillars. These trials were coupled with elemental analysis of the gut and body tissues of both D. plexippus caterpillars and corn borers. Cardenolides did not affect mantid behavior: mantids gutted both cardenolide-containing and cardenolide-free caterpillars. In contrast, mantids consumed both O. nubilalis and starved D. plexippus caterpillars entirely. Danaus plexippus body tissue has a lower C:N ratio than their gut contents, while O. nubilalis have similar ratios; gutting may reflect the mantid’s ability to regulate nutrient uptake. Our results suggest that post-capture prey processing by mantids is likely driven by a sophisticated assessment of resource quality

Seasonal changes in eastern hemlock (\u3cem\u3eTsuga canadensis\u3c/em\u3e) foliar chemistry

Eastern hemlock (Tsuga canadensis (L.) Carriére; hemlock) is an eastern North American conifer threatened by the invasive hemlock woolly adelgid (Adelges tsugae Annand). Changes in foliar terpenes and phenolics were evaluated in new (current year growth) and mature (1-year old growth) hemlock needles during the growing season and into plant dormancy. From April through September, foliar concentrations of non-volatile soluble phenolics, condensed tannins, lignin, mono- and sesquiterpenes α-pinene, camphene, isobornyl acetate, and diterpene resin were quantified. After September, additional analyses of metabolites that continued to differ significantly in new versus mature foliage were carried out. Total soluble phenolic concentration and condensed tannin concentration in new foliage remained low relative to mature foliage throughout the growing season and converged in December. Lignin concentration in new foliage converged with that of mature foliage by July. Concentrations of α-pinene, camphene, isobornyl acetate, and diterpene resin in new foliage converged with mature foliage within one month of budbreak. The convergence of terpene concentrations in new and mature foliage suggests that these metabolites may play a role in herbivore defense during the peak growing season. Conversely, soluble phenolics, including condensed tannins, may defend foliage from herbivory outside of the spring growth period

Impact of Hemlock Woolly Adelgid (Hemiptera: Adelgidae) Infestation on the Jasmonic Acid-Elicited Defenses of Tsuga canadensis (Pinales: Pinaceae)

Hemlock woolly adelgid is an invasive piercing-sucking insect in eastern North America, which upon infestation of its main host, eastern hemlock (‘hemlock’), improves attraction and performance of folivorous insects on hemlock. This increased performance may be mediated by hemlock woolly adelgid feeding causing antagonism between the the jasmonic acid and other hormone pathways. In a common garden experiments using hemlock woolly adelgid infestation and induction with methyl jasmonate (MeJA) and measures of secondary metabolite contents and defense-associated enzyme activities, we explored the impact of hemlock woolly adelgid feeding on the local and systemic induction of jasmonic acid (JA)-elicited defenses. We found that in local tissue hemlock woolly adelgid or MeJA exposure resulted in unique induced phenotypes, whereas the combined treatment resulted in an induced phenotype that was a mixture of the two individual treatments. We also found that if the plant was infested with hemlock woolly adelgid, the systemic response of the plant was dominated by hemlock woolly adelgid, regardless of whether MeJA was applied. Interestingly, in the absence of hemlock woolly adelgid, hemlock plants had a very weak systemic response to MeJA. We conclude that hemlock woolly adelgid infestation prevents systemic induction of JA-elicited defenses. Taken together, compromised local JA-elicited defenses combined with weak systemic induction could be major contributors to increased folivore performance on hemlock woolly adelgid-infested hemlock

Facilitation between invasive herbivores: hemlock woolly adelgid increases gypsy moth preference for and performance on eastern hemlock

Interactions between invertebrate herbivores with different feeding modes are common on long‐lived woody plants. In cases where one herbivore facilitates the success of another, the consequences for their shared host plant may be severe. Eastern hemlock (Tsuga canadensis), a canopy‐dominant conifer native to the eastern U.S., is currently threatened with extirpation by the invasive stylet‐feeding hemlock woolly adelgid (Adelges tsugae). The effect of adelgid on invasive hemlock‐feeding folivores remains unknown. This study evaluated the impact of feeding by hemlock woolly adelgid on gypsy moth (Lymantria dispar) larval preference for, and performance on, eastern hemlock. To assess preference, 245 field‐grown hemlocks were surveyed for gypsy moth herbivory damage and laboratory paired‐choice bioassays were conducted. To assess performance, gypsy moth larvae were reared to pupation on adelgid‐infested or uninfested hemlock foliage, and pupal weight, proportional weight gain, and larval period were analysed. Adelgid‐infested hemlocks experienced more gypsy moth herbivory than did uninfested control trees, and laboratory tests confirmed that gypsy moth larvae preferentially feed on adelgid‐infested hemlock foliage. Gypsy moth larvae reared to pupation on adelgid‐infested foliage gained more weight than larvae reared on uninfested control foliage. These results suggest that the synergistic effect of adelgid and gypsy moth poses an additional threat to eastern hemlock that may increase extirpation risk and ecological impact throughout most of its range

WHO collaborative study to assess the suitability of the 1st International Standard and the 1st International Reference Panel for antibodies to Ebola virus

A WHO international collaborative study was undertaken to evaluate preparations of Ebola virus disease (EVD) convalescent plasmas for their suitability to serve as the WHO 1st International Standard (IS) and the WHO 1st International Reference Panel (IRP) for Ebola virus antibodies for use in the standardization and control of assays. The study involved participants testing the convalescent plasma sample preparations and additional monoclonal antibody samples in a blinded manner alongside the WHO International Reference Reagent (NIBSC code 15/220) using anti-EBOV assays established in their laboratories. The candidate 1st IS for Ebola virus antibodies (study sample code 92, NIBSC 15/262) consists of ampoules containing the freeze-dried equivalent of 0.5 mL pooled convalescent plasma obtained from six Sierra Leone patients recovered from EVD. The candidate 1st IRP of anti-Ebola virus convalescent plasmas (NIBSC 16/344) consists of freeze-dried preparations of single donations of convalescent plasma obtained from four patients and one healthy blood donor. Each panel member is an ampoule containing the equivalent of 0.25mL plasma. All convalescent plasmas are confirmed PCR-negative for Ebola virus and underwent, along with the negative plasma, solvent detergent (SD) treatment prior to their development into candidate WHO biological reference materials. In this collaborative study, 17 laboratories from 4 countries used a range of live Ebola virus neutralization assays, pseudotyped virus neutralisation assays and enzyme immunoassays to test the collaborative study samples. Surface plasmon resonance and Western blot assessments were also undertaken. The study found that the candidate International Standard has the highest absolute titre among the convalescent plasma samples, although the geometric mean titres of all the convalescent plasmas fall within ~5-fold of each other. The potencies of three of the convalescent samples fall near the detection limit of some assays. This study also demonstrated that the agreement between laboratories for potencies relative to the candidate International Standard represents an improvement compared to the agreement in absolute titres; however, there is poor agreement between relative potencies for some assays. The results obtained from accelerated thermal degradation studies at 1year indicate that the candidate IS is stable and suitable for long-term use. The results of the collaborative study indicate the suitability of the candidates to serve as WHO reference materials and it is proposed that 15/262 is established as the WHO 1st IS for EBOV antibodies with an assigned potency of 1.5 IU/mL when reconstituted as directed in the instructions for use. It is also proposed that 16/344 is established as the WHO 1st IRP of anti-EBOV convalescent plasmas with panel member code 95 (NIBSC 15/280) assigned a unitage of 1.1 IU/mL when reconstituted as directed in the instructions for use. The other panel members have not been assigned a unitage. The implementation and use by laboratories of the proposed WHO reference materials for EBOV antibodies will facilitate the characterization of the factors that contribute to assay variability and standardization of results across assays and laboratorie