Burkholderia spp.-based biopesticide controls wireworms (Coleoptera: Elateridae) in potatoes.

Wireworms (Coleoptera: Elateridae) are economically significant pests of potatoes (Solanum tuberosum), damaging the marketable portion of the crop by feeding and tunneling into tubers. While conventional potato growers use the few registered synthetic insecticides to control wireworms, certified organic growers are left with less options due to the limited effectiveness of the available insecticides. Biologically derived pesticides provide an additional alternative for both systems. Certain gram-negative proteobacteria, such as Burkholderia spp., possess insecticidal compounds. However, very little is known about their efficacy on wireworms. From 2018 to 2021, we conducted experiments in Virginia to assess the efficacy of a Burkholderia spp.-based commercial pesticide, Majestene, as a wireworm control in potatoes. In a lab experiment, soil drench application of this insecticide at a rate of 66 g a.i. per 1 liter resulted in 30% wireworm mortality and significantly reduced wireworm feeding damage on potato tubers. In the field, in-furrow applications of Burkholderia spp. at a rate of 17.66 kg a.i. per ha significantly reduced wireworm damage to tubers in 2 of 7 field experiments conducted. By comparison, the commercial standard insecticide, bifenthrin, significantly reduced tuber damage in 3 of the 7 field experiments. Our study demonstrates the prospect for proteobacteria-derived insecticides for control of wireworms and potentially other soil-dwelling insects. In conclusion, findings present growers with another option to combat wireworm pressure, especially in organic systems.

Dendrochronology reveals different effects among host tree species from feeding by Lycorma delicatula (White).

The spotted lanternfly, Lycorma delicatula (White) (Hemiptera: Fulgoridae), was first detected in the United States in Berks County, Pennsylvania, in 2014. Native to China, this phloem-feeding planthopper threatens agricultural, ornamental, nursery, and timber industries in its invaded range through quarantine restrictions on shipments, as well as impacts on plants themselves. The long-term impacts of L. delicatula feeding on tree species have not been well studied in North America. Using standard dendrochronological methods on cores taken from trees with differing levels of L. delicatula infestation and systemic insecticidal control, we quantified the impact of L. delicatula feeding on the annual growth of four tree species in Pennsylvania: Ailanthus altissima, Juglans nigra, Liriodendron tulipifera, and Acer rubrum. The results suggest that L. delicatula feeding is associated with the diminished growth of A. altissima, but no change was observed in any other tree species tested. The results also suggest that systemic insecticides mitigate the impact of L. delicatula feeding on A. altissima growth.

Effect of Vegetable Host Plant Type on Halyomorpha halys (Hemiptera: Pentatomidae) Nymphal Development.

The brown marmorated stink bug, Halyomorpha halys (Stål), is an invasive pest introduced to North America in the mid-1990's that has caused economic losses to a wide range of commodities. In vegetables, H. halys feeding damage has been well described, but the effect of different vegetable hosts on H. halys fitness is less understood. We caged 2nd instar H. halys on different vegetable hosts (e.g., tomato, sweet corn, eggplant, bell pepper, and snap bean) and monitored their development until adulthood to compare the effects of vegetable host type on H. halys nymph survival and development time. Experiments were replicated nine times over a two-year period. Survival of 2nd instars from F1 generation (early-season) eggs was low (<30%) on all vegetables resulting in no significant treatment effect. However, H. halys nymphs collected from F2 generation (late-season) eggs had higher survivorship on all vegetables except tomato. The percentage of H. halys 2nd instars that reached adulthood was greatest on corn (53%) and pepper (45%), followed by snap bean (24%), and significantly lower on eggplant (9%) and tomato (2%). Total development time from 2nd instar to adult was fastest on corn and slowest on peppers, although tomatoes were not tested due to the low survival. Trends in development rate were not seasonally-dependent. Our study compares H. halys survivability on several vegetable commodities, and provides insights into H. halys developmental success and dependence on various host plants over the season.

Effect of Plastic Mulch Colors on Anasa tristis (Hemiptera: Coreidae) Population Dynamics in Summer Squash, Cucurbita pepo (Cucurbitales: Cucurbitaceae).

The squash bug, Anasa tristis (De Geer), is a serious pest of cucurbit crops across the United States, especially within summer squash (Cucurbita pepo L.) systems. Using their piercing sucking mouthparts, squash bugs feed on both leaf tissue and fruits, often leading to leaf necrosis, marketable fruit loss, and even plant death. To date, the relationship between squash bug presence and plasticulture has not been adequately investigated. This 2-yr study evaluated the effects of white, black, and reflective plastic mulch colors on the occurrence of all squash bug life stages and marketable zucchini yield in Virginia. In both years, A. tristis adults and egg masses were more numerous on zucchini plants grown in white and reflective plastic mulch compared to bare ground plants. Greater nymphal densities and marketable fruit yield were observed in certain plastic mulch treatments versus the bare ground treatment, yet these differences were not consistent in both years. Contrary to the repellency effects reflective mulches have on other cucurbit insect pests, our research suggests that reflective and other plastic mulch colors can negatively impact squash bug management, especially in regions with high A. tristis pressure. Our study offers new insights for cucurbit growers to use when considering whether they should implement plasticulture in their growing systems.

Environmentally Benign Nanoantibiotics with a Built-in Deactivation Switch Responsive to Natural Habitats.

The massive use of antibiotics in healthcare and agriculture has led to their artificial accumulation in natural habitats, which risks the structure and function of the microbial communities in ecosystems, threatens food and water security, and accelerates the development of resistome. Ideally, antibiotics should remain fully active in clinical services while becoming deactivated rapidly once released into the environment, but none of the current antibiotics meet this criterion. Here, we show a nanoantibiotic design that epitomizes the concept of carrying a built-in "OFF" switch responsive to natural stimuli. The environmentally benign nanoantibiotics consist of cellulose backbones covalently grafted with hydrophilic polymer brushes that by themselves are antimicrobially inactive. In their nanostructured forms in services, these cellulose-based polymer molecular brushes are potent killers for both Gram-positive and Gram-negative bacteria, including clinical multidrug-resistant strains; after services and being discharged into the environment, they are shredded into antimicrobially inactive pieces by cellulases that do not exist in the human body but are abundant in natural habitats. This study illuminates a new concept of mitigating the environmental footprints of antibiotics with rationally designed nanoantibiotics that can be dismantled and disabled by bioorthogonal chemistry occurring exclusively in natural habitats.

A pilot study describing physical activity in persons with schizophrenia spectrum disorders (SSDS) after an exercise program.

Despite the well known mental and physical health benefits of exercise, persons with schizophrenia spectrum disorders remain sedentary. While the exercise barriers (i.e., lack of motivation, poor concentration, sedative effects of medication, poverty, and lack of access to exercise education/programs) of persons with SSDs are numerous, lack of motivation is considered foremost among them. Exercise interventions have been shown to improve exercise behavior, but there is a need for longitudinal documentation of physical activity after interventions conclude. This pilot study describes the physical activity level of 22 persons with SSDs 14 to 34 (mean 22) months after the conclusion of an exercise intervention provided in a randomized controlled trial (RCT). Eighteen months after the RCT, 22 participants wore pedometers daily for one week without altering their activity. Experimental participants walked more steps and covered more distance on average than control participants on six of the seven days. This pilot study is among the first to document the physical activity level of persons with SSDs after exercise intervention. While our findings confirm the low activity level of persons with SSDs reported by others, experimental participants demonstrated higher activity levels than controls on most days. Future studies should increase the sample size and recruit participants from multiple sites to enhance power and generalizability.

Effect of a motivational intervention on exercise behavior in persons with schizophrenia spectrum disorders.

Ninety seven outpatients with schizophrenia spectrum disorders (SSDs) were randomly assigned to the Walk, Address Sensations, Learn About Exercise, Cue Exercise Behavior for SSDs (WALC-S), a motivational intervention designed to increase exercise in SSDs (n = 48), or a time and attention control group (TAC, n = 49). WALC-S and TAC groups met weekly for 4 weeks before a 16 week walking program was offered to all subjects. We compared the exercise attendance, persistence and compliance of the groups during the walking program. WALC-S recipients attended more walking groups, for more weeks and walked more minutes than those receiving TAC. Percent of WALC-S or TAC groups attended was significantly correlated with overall attendance (r = 0.38, P = 0.001) and persistence (r = -.29, P = 0.01), as well as number of minutes walked. This study is among the first to examine interventions designed to enhance exercise motivation in SSDs.

Organizational downsizing and age discrimination litigation: the influence of personnel practices and statistical evidence on litigation outcomes.

The present study examined relationships between reduction-in-force (RIF) personnel practices, presentation of statistical evidence, and litigation outcomes. Policy capturing methods were utilized to analyze the components of 115 federal district court opinions involving age discrimination disparate treatment allegations and organizational downsizing. Univariate analyses revealed meaningful links between RIF personnel practices, use of statistical evidence, and judicial verdict. The defendant organization was awarded summary judgment in 73% of the claims included in the study. Judicial decisions in favor of the defendant organization were found to be significantly related to such variables as formal performance appraisal systems, termination decision review within the organization, methods of employee assessment and selection for termination, and the presence of a concrete layoff policy. The use of statistical evidence in ADEA disparate treatment litigation was investigated and found to be a potentially persuasive type of indirect evidence. Legal, personnel, and evidentiary ramifications are reviewed, and a framework of downsizing mechanics emphasizing legal defensibility is presented.