Erwinia tracheiphila is one of the most economically important pathogens of cucumbers, melons, sq... more Erwinia tracheiphila is one of the most economically important pathogens of cucumbers, melons, squashes, pumpkins, and gourds in the northeastern and midwestern United States, yet its molecular pathology remains uninvestigated. Here, we report the first draft genome sequence of an E. tracheiphila strain isolated from an infected wild gourd (Cucurbita pepo subsp. texana) plant. The genome assembly consists of 7 contigs and includes a putative plasmid and at least 20 phage and prophage elements
Allium leafminer, Phytomyza gymnostoma (Diptera: Agromyzidae), is an invasive species first recor... more Allium leafminer, Phytomyza gymnostoma (Diptera: Agromyzidae), is an invasive species first recorded in the Western Hemisphere in 2015 and has expanded its range into northeastern and MidAtlantic states. Its host range encompasses Allium species grown for food and ornamentals, weedy species, species used for pollinator provisioning, and species of conservation concern. Using field and laboratory studies, we advanced methods for rearing, developed a phenology model for spring emergence, describe pupal development, and report on parasitism. Spring emergence was best detected by scouting wild alliums as opposed to emergence cages, and modeled using 350 degree-days above a lower threshold of 1.0°C. Spring adult flight occurred for about 5 wk. Larval development required 22 and 20 d at 17.5 and 25°C, respectively. Pupal development progressed along a color gradient, and an initial presence of fat cell clusters and an air bubble, followed by an exarate pupa. Pupal developed at 3–5% per da...
Aims: We aim to determine if Pseudomonas fluorescens is a viable biological control for Erwinia t... more Aims: We aim to determine if Pseudomonas fluorescens is a viable biological control for Erwinia tracheiphila within the insect vector, Acalymma vittatum. Methods and Results: Pseudomonas fluorescens secreted fluorescein and inhibited growth of Erwinia tracheiphila in disk diffusion assays. To determine if this antagonism was conserved within the insect vector, we performed in vivo assays by orally injecting beetles with bacterial treatments and fluorescent in situ hybridization to determine bacterial presence within the alimentary canal. Conclusions: Pseudomonas fluorescens inhibited the growth of Erwinia tracheiphila on a nutrientlimiting medium. In situ experiments demonstrated that Pseudomonas fluorescens is maintained Accepted Article This article is protected by copyright. All rights reserved. within the alimentary canal of the beetle for at least 4 days, and co-occurred with Erwinia tracheiphila. When beetles were first presented with Pseudomonas and then challenged with Erwinia tracheiphila, Erwinia tracheiphila was not recovered via FISH after 4 days. These data suggest that Pseudomonas fluorescens has potential as a biological control agent to limit Erwinia tracheiphila within the insect vector. Significance and Impact of Study: This is a novel approach for controlling Erwinia tracheiphila that has the potential to decrease reliance on insecticides, providing a safer environment for pollinators and growers.
The invasive species Phytomyza gymnostoma (Loew) (Diptera: Agromyzidae), also know as the Allium ... more The invasive species Phytomyza gymnostoma (Loew) (Diptera: Agromyzidae), also know as the Allium Leafminer, is reported from the United States for the first time. The first specimens were collected in Lancaster County, PA, USA in December 2015. An additional 19 counties in Pennsylvania and two states were confirmed in 2016. The species' North American distribution, pest implications, and observations on their biology in the New World are reviewed.
Loss in the availability of early successional habitat is a threat to pollinator populations. Giv... more Loss in the availability of early successional habitat is a threat to pollinator populations. Given that powerline rights-of-way (ROW) must be managed to maintain early successional habitat, preventing vegetation from interfering with electrical lines, they have the potential to provide conservation benefits for wild pollinators. Moreover, it is possible to provide conservation benefits with no additional cost to land managers. We surveyed flower-visiting insects over two years in different vegetation management treatments in a long-term research ROW to determine which best promoted pollinator abundance and species richness. We found that the ROW had stabilized in an early successional state soon after its establishment and that this early successional state could be maintained with low levels of periodic maintenance. We collected a high diversity of flower-visiting insects (126 bee species and 179 non-bee morphospecies) in six ROW plots. Higher levels of herbicide application had a...
Erwinia tracheiphila is one of the most economically important pathogens of cucumbers, melons, sq... more Erwinia tracheiphila is one of the most economically important pathogens of cucumbers, melons, squashes, pumpkins, and gourds in the northeastern and midwestern United States, yet its molecular pathology remains uninvestigated. Here, we report the first draft genome sequence of an E. tracheiphila strain isolated from an infected wild gourd ( Cucurbita pepo subsp. texana ) plant. The genome assembly consists of 7 contigs and includes a putative plasmid and at least 20 phage and prophage elements.
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