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Thousand cankers disease (TCD) is caused by the fungal pathogen Geosmithia morbida and vectored by the walnut twig beetle Pityophthorus juglandis. In infected walnut and butternut (Juglans spp.) hosts and wingnut species (Pterocarya spp.) hosts, tree decline and death results in ecological disruption and economic losses. A rapid molecular detection protocol for TCD using microsatellite markers can confirm the presence of insect vector or fungal pathogen DNA, but it requires specialized expensive equipment and technical expertise. Using four different experimental approaches, capillary and conventional gel electrophoresis, and traditional polymerase chain reaction (PCR) and quantitative PCR (qPCR), we describe simplified and inexpensive processes for diagnostic confirmation of TCD. The improved and rapid detection protocols reported in this study reduce time and equipment costs associated with detection of molecular pest and pathogen DNA by (1) using conventional gel electrophoresis or TaqMan molecular probes to elucidate the detection limits for G. morbida and P. juglandis DNA and (2) identifying resources that allow visualization of positive test results for infected host plant tissue samples. Conventional gel electrophoresis and TaqMan molecular probe protocols detected presence of DNA from TCD-associated fungal and insect samples. These procedural improvements can be readily adopted by diagnostic end-users and adapted for use with other complex disease systems to enable rapid pest and pathogen detection. [Formula: see text] Copyright © 2021 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license .

While horticultural therapy (HT) has a long history in the United States, the profession has not had the acceptance and growth that related fields, such as art, music, recreational, occupational, and physical therapies have experienced. The objective of this study was to identify the current challenges and opportunities of HT in the United States. Maximum variation sampling was used to select current and former members of the American Horticultural Therapy Association (AHTA) for interviews. A total of 27 participants were interviewed between Nov. 2019 and Jan. 2020 using semi-structured qualitative interviews by Zoom. The interviews revealed six themes: 1) current state of the profession, 2) AHTA operations/structure, 3) education/credentialing, 4) funding/job opportunities, 5) public awareness/networking, and 6) research. This paper will discuss the challenges and opportunities presented in the six themes and provide recommendations for the future growth of the HT profession.

Helianthus verticillatus Small (whorled sunflower) is a federally endangered plant species found only in the southeastern United States that has potential horticultural value. Evidence suggests that H. verticillatus is self-incompatible and reliant on insect pollination for seed production. However, the identity of probable pollinators is unknown. Floral visitors were collected and identified during Sept. 2017 and Sept. 2018. Thirty-six species of visitors, including 25 hymenopterans, 7 dipterans, 2 lepidopterans, and 2 other insect species, were captured during 7 collection days at a site in Georgia (1 day) and 2 locations in Tennessee (6 days). Within a collection day (0745–1815 hr), there were either five or six discrete half-hour collection periods when insects were captured. Insect visitor activity peaked during the 1145–1215 and 1345–1415 hr periods, and activity was least during the 0745–0845 and 0945–1015 hr periods at all three locations. Visitors were identified by genus and/or species with morphological keys and sequences of the cox-1 mitochondrial gene. The most frequent visitors at all sites were Bombus spp. (bumblebees); Ceratina calcarata (a small carpenter bee species) and members of the halictid bee tribe Augochlorini were the second and third most common visitors at the two Tennessee locations. Helianthus pollen on visitors was identified by microscopic observations and via direct polymerase chain reaction of DNA using Helianthus-specific microsatellites primers. Pollen grains were collected from the most frequent visitors and Apis mellifera (honeybee) and counted using a hemocytometer. Based on the frequency of the insects collected across the three sites and on the mean number of pollen grains carried on the body of the insects, Bombus spp., Halictus ligatus (sweat bee), Agapostemon spp., and Lasioglossum/Dialictus spp., collectively, are the most probable primary pollinators of H. verticillatus.

Tapinoma sessile (Say) is a common ant throughout the United States that frequently relocates portions of its nests to form large polydomous colonies in urban areas. Despite widespread research on the control of T. sessile as a nuisance pest, relatively little work has focused on the biology of its nesting behavior and movement. We evaluated shade, moisture, and proximity to food as factors triggering colony movement in laboratory assays. Initially, T. sessile colonies moved to shaded artificial nest sites irrespective of arena moisture. Then, workers and brood were increasingly moved to moist artificial nest sites over time. Colonies moved workers and brood to near-food artificial nest sites over both 1 m and 6 m distances. Queens relocated to near-food nest sites over 1 m distances, but not 6 m distances, during the 49-d study. Results suggest that an increase either in moisture or food in proximity to a residence is likely to account for observed increases in T. sessile abundance near structures.

Estimates about which scale insect species are most frequently encountered in U.S. landscapes and commercial production systems are largely anecdotal. This survey of records maintained across about 15 years within the National Plant Diagnostic Network (NPDN) National Data Repository (NDR) returned information from 10,671 records of 192 scale insect species and 23 suspected species that were associated with ornamental plants. This broad species diversity challenges our ability to effectively train diagnosticians, can confound species identification accuracy, and impedes outreach efforts and resource development. To help focus future efforts in the development of outreach resources and diagnostic training guides, lists were assembled that identified the 60 top-ranked soft, armored, mealybug, and other scale insect taxa most frequently diagnosed within NDR records. Diagnostic service records from Georgia, North Carolina, South Carolina, and Tennessee provided more extensive information regarding sites or client types from which submitted samples originated. Results are being used to develop web-based, image-rich guides to key scale insect taxa in the southeastern United States that will explain life cycles, behaviors, and biology for pest species. These web-based guides can be exploited to optimize pest management actions.

Branch and stem cankers caused by Geosmithia morbida associated with mass attack by its primary insect vector (Pityophthorus juglandis) result in thousand cankers disease (TCD) on Juglans and Pterocarya species. Because other fungi and insects can cause visible damage to Juglans nigra, a baseline assessment was performed to document damage types present and to characterize fungi associated with each type. Two branches were collected from trees with visually healthy crowns in TCD-free locations (Indiana and Missouri) and two branches from trees with and without crown symptoms characteristic of TCD within the disease range in Tennessee. In most cases, one of the two branches was girdled at the base 3 to 4 months prior to harvest. Outer bark was peeled from branch subsamples, observed damage characterized, and isolation of fungi from each damage type attempted. Three known pathogens of J. nigra were obtained from different damage types: G. morbida, in Tennessee only; Botryosphaeria dothidea, in Indiana and Tennessee; and Fusarium solani (= members of F. solani species complex), in all three states. The latter two fungi may exacerbate branch dieback and mortality of TCD-affected trees. These results will be of value to plant health specialists monitoring J. nigra in the field and laboratory diagnosticians processing survey samples.

Thousand cankers disease (TCD) results from the combined activity of the fungal pathogen, Geosmithia morbida Kolařík, Freeland, Utley, and Tisserat and its principle vector, Pityophthorus juglandis (Blackman) (Coleoptera: Curculionidae: Scolytinae) in Juglans L. spp. and Pterocarya Kunth spp. host plants. TCD has been reported from the eastern and western United States. To evaluate potential for other beetle species to vector the fungus in east Tennessee, specimens were collected using ethanol-baited traps that were suspended beneath crowns of TCD-symptomatic trees. Associations of G. morbida with insect species collected in traps were assessed in an unsuccessful, preliminary culture-based fungal assay, and then with a molecular-based detection method. For culture-based assays, rinsate from washed, individual insects was plated on nutrient media and growing colonies were subcultured to obtain axenic G. morbida cultures for identification. For the molecular-based method, G. morbida presence was detected by amplifying the previously developed, species-specific microsatellite locus GS004. Capillary electrophoresis was used to detect the amplified amplicons and representative reactions were validated using Sanger sequencing. Eleven beetle species were found to carry G. morbida, including Cnestus mutilatus (Blandford), Dryoxylon onoharaensum (Murayama), Hylocurus rudis (LeConte), Monarthrum fasciatum (Say), Monarthrum mali (Fitch), Xyleborinus saxesenii (Ratzeburg), Xylosandrus crassiusculus (Motschulsky), Xylosandrus germanus (Blandford) (all Coleoptera: Curculionidae: Scolytinae), Stenomimus pallidus (Boheman) (Coleoptera: Curculionidae: Cossoninae), Oxoplatypus quadridentatus (Olivier) (Coleoptera: Curculionidae: Platypodinae), and Xylops basilaris (Say) (Coleoptera: Bostrichidae). These findings raise concerns that alternative subcortical insect species that already occur within quarantined habitats can sustain incidence of introduced G. morbida and contribute to spread within the native range of black walnut, Juglans nigra L., in the eastern United States.

Pyrus calleryana Decne. (Callery pear) includes cultivars that in the United States are popular ornamentals in commercial and residential landscapes. Last few decades, this species has increasingly naturalized across portions of the eastern and southern US. However, the mechanisms behind this plant’s spread are not well understood. The genetic relationship of present-day P.calleryana trees with their Asian P. calleryana forebears (native trees from China, Japan, and Korea) and the original specimens of US cultivars are unknown. We developed and used 18 microsatellite markers to analyze 147 Pyrus source samples and to articulate the status of genetic diversity within Asian P. calleryana and US cultivars. We hypothesized that Asian P. calleryana specimens and US cultivars would be genetically diverse and would show genetic relatedness. Our data revealed high genetic diversity, high gene flow, and presence of population structure in P. calleryana, potentially relating to the highly invasive capability of this species. Strong evidence for genetic relatedness between Asian P. calleryana specimens and US cultivars was also demonstrated. Our data suggest the source for P. calleryana that have become naturalized in US was China. These results will help understand the genetic complexity of invasive P. calleryana when developing management for escaped populations: In follow-up studies, we use the gSSRs developed here to analyze P. calleryana escape populations from across US.

The Viburnum genus is of particular interest to horticulturalists, phylogeneticists, and biogeographers. Despite its popularity, there are few existing molecular markers to investigate genetic diversity in this large genus, which includes over 160 species. There are also few polymorphic molecular tools that can delineate closely related species within the genus. Viburnum farreri, a member of the Solenotinus subclade and one of the centers of diversity for Viburnum, was selected for DNA sequencing and development of genomic simple sequence repeats (gSSRs). In this study, 15 polymorphic gSSRs were developed and characterized for a collection of 19 V. farreri samples. Number of alleles per locus ranged from two- to- eight and nine loci had four or more alleles. Observed heterozygosity ranged from 0 to 0.84 and expected heterozygosity ranged from 0.10 to 0.80 for the 15 loci. Shannon diversity index values across these loci ranged from 0.21 to 1.62. The markers developed in this study add to the existing molecular toolkit for the genus and will be used in future studies investigating cross-transferability, genetic variation, and species and cultivar delimitation in the Viburnum genus and closely allied genera in the Adoxaceae and Caprifoliaceae.

Neothaumalea atlanticanew genus, new species (Diptera: Thaumaleidae), is described from the state of Santa Catarina in southern Brazil. This represents the first thaumaleid collected east of the Andes mountain range. The egg, larva, pupa, and both adults are described and illustrated, distribution map presented, and phylogenetic affinities discussed. A key to the genera of South America is also provided.

Thousand Cankers Disease (TCD) affects Juglans and Pterocarya species. This disease poses not only a major threat to the nut and timber industries but also to native stands of walnut trees. Galleries created by Pityophthorus juglandis (vector) are colonized by the fungus Geosmithia morbida (causal agent of necrosis). It is unknown if other fungi colonizing these galleries might act antagonistically towards G. morbida. The objectives of this study were to: (1) characterize the fungal community associated with TCD-infected trees and (2) develop a pilot study addressing their potential antagonism towards G. morbida. We collected non-Geosmithia fungi from ten TCD-infected walnut trees from California and Tennessee. Four hundred and fifty-seven isolates, representing sixty-five Operational Taxonomic Units (99 % ITS similarity) were obtained. Fungal communities were found to be highly diverse. Ophiostoma dominated the communities associated with TCD-compromised trees from California, whereas Trichoderma dominated TCD-compromised trees in Tennessee. Six Trichoderma isolates showed varying levels of antagonism against three isolates of G. morbida, suggesting potential applications for the biological control of TCD. Furthermore, results from this study contribute to the growing knowledge about the observed differential disease development between the western and eastern USA and could overall impact our understanding of TCD etiology.

Ornamental plant producers often rely on chemical control to manage insect pests. However, cultural practices, such as pruning, can influence plant architecture which may, in turn, affect pesticide penetration. Spray penetration was studied to determine the effect of canopy density on beneficial insect survival following insecticide application and to better understand the implications of canopy density on pest management. Regardless of canopy density or plant species, the interior position of the canopy received less than 8% spray coverage. The middle position of sparse canopies received 288 to 513% more coverage than the middle position of dense canopies. The middle and interior position of dense canopies protected greater than 50% of the convergent lady beetle (Hippodamia convergens (Guérin-Méneville) population while only the interior position of dense canopies protected greater than 50% of green lacewing (Chrysoperla rufilabris Burmeister) populations. Index words: beneficial insect, nursery crop, pesticide, plant architecture, woody ornamental. Species used in this study: China Girl® holly (Ilex ×meserveae ‘Mesog'); ‘Alice' Oakleaf hydrangea (Hydrangea quercifolia Bartr. ‘Alice'); convergent lady beetle [Hippodamia convergens (Guérin-Méneville)]; green lacewing [Chrysoperla rufilabris (Burmeister)]. Chemicals used in this study: carbaryl (1-naphthyl N-methylcarbamate, Sevin® SL, Bayer CropScience, Durham, NC).

Three, 2-day hands-on experiential learning workshops were presented in three southeastern United States cities in June 2014, by the Southern Nursery Integrated Pest Management (SNIPM) working group. Attendees were provided 4 hours of instruction including hands-on demonstrations in horticultural management, arthropods, plant diseases, and weeds. Participants completed initial surveys for gains in knowledge, skills, and abilities as well as their intentions to adopt various integrated pest management (IPM) practices after the workshop. After 3 years, participants were again surveyed to determine practice adoption. Respondents changed their IPM practice behavior because of attending the workshops. Those returning the survey set aside more time to scout deliberately for pests, plant diseases, and weeds; used a standardized sampling plan when scouting; and adopted more sanitation practices to prevent plant disease. Fewer horticultural management practices were adopted than respondents originally intended. Future emphasis should be placed on using monitoring techniques to estimate pest emergence, for example, traps and pheromone lures, as well as plant phenology and record keeping. However, more work is needed to highlight both the immediate and long-term economic benefits of IPM practice adoption in southeastern U.S. nursery production.

Extension and research professionals in the southeastern United States formed the Southern Nursery Integrated Pest Management working group (SNIPM) to foster collaboration and leverage resources, thereby enhancing extension programming, increasing opportunity, and expanding the delivery of specialized expertise to nursery crop growers across a region. Building a productive and lasting working group requires attracting a group of research and extension faculty with complementary expertise, listening to stakeholders, and translating stakeholder needs into grant priorities to help solve problems, all hallmarks of effective teamwork principles. SNIPM has now grown to include 10 U.S. states and 11 institutions and has been awarded seven grants totaling $190,994 since 2009. A striking benefit of working group membership was observed over time: synergy. Greater awareness of individual expertise among SNIPM members, each of whom were focused on different aspects of the nursery production system stimulated multistate extension publications, electronic books (eBooks), mobile device applications (apps), popular press articles, and spin-off research projects when separate foci were combined and directed toward complex challenges. Deliverables achieved from this faculty collaboration include nine peer-reviewed publications, four manuals and books and 23 book chapters, and a combined total of 11 abstracts, conference proceedings and extension publications. To date, the return on investment for SNIPM is one deliverable produced to every $2265.89 in grant funding. SNIPM has also been honored with multiple American Society for Horticultural Science publication awards as well as the Southern Region Integrated Pest Management Center Bright Idea Award for the quality and originality of their project outputs. Continuing to work together toward common goals that bridge technology and serve the nursery industry while supporting each individual member’s program will be crucial to the long-term success of this working group.

Knowledge about which bark and ambrosia beetle species are active and at what heights in black walnut canopies is not well understood. Neither is the role of these beetles in spreading Thousand Cankers Disease. To assist with future planned research, which will assess the extent to which these beetle species are associated with Geosmithia morbida Kolařík, Freeland, Utley, and Tisserat (Ascomycota: Hypocreales: Bionectriaceae), experiments were undertaken to monitor bark and ambrosia beetles in urban landscapes and parks in Tennessee between 2011 and 2013. Within mature walnut tree canopies, sticky panel, modified soda bottle, and Lindgren traps were deployed at different heights, with and without ethanol as an attractant and with and without walnut stem sections, or in situ limbs that had been girdled or injection with ethanol to simulate stressed tree tissues. Bark and ambrosia beetle species (Coleoptera: Curculionidae: Scolytinae) collected in greatest abundance included Ambrosiodmus rubricollis (Eichhoff), Ambrosiophilus atratus (Eichhoff), Cnestus mutilatus (Blandford), Dryoxylon onoharaense (Murayama), Euwallacea validus (Eichhoff), Monarthrum fasciatum (Say), Monarthrum mali (Fitch), Xyleborinus saxesenii (Ratzeburg), Xyleborus affinis Eichhoff, Xyleborus ferrugineus (Fabricius), Xylosandrus crassiusculus (Motschulsky), and Xylosandrus germanus (Blandford). C. mutilatus, X. saxesenii, and X. crassiusculus were more active higher in trees than most other species and were strongly attracted to ethanol via all means of lure deployment. C. mutilatus, which were captured from April through October and increased in abundance across the 3-yr study, were most abundant in late May with a second activity period in late August.

Efforts to document species of longhorned beetles (Coleoptera: Cerambycidae) occurring in Tennessee have not been updated since 1973. To address this knowledge gap, institutional, research, and private collections in Tennessee were reviewed to provide faunal distribution assessments and seasonal activity data for the cerambycid beetle species active in Tennessee. Examinations of 9,918 specimens and records yielded a list of 230 cerambycid beetle species within 5 subfamilies. Twenty-seven species are reported as new state records from Tennessee. Adult seasonal activity data that were recorded on specimen labels are presented. Where available, notes on collection method, adult resources, and larval host plants are provided for species within a supplementary table. Supplemental figures report the distribution for species collected across the state and from 85 of the 95 Tennessee counties, as well as the ecoregions from which each species is reported. The bias-corrected Chao1 species richness estimator predicts another 11 species remain to be identified across the state. Future collection efforts in the Central Appalachian, Mississippi Alluvial and Valley Loess Plains, Southeastern Plains, and western portions of the Interior Plateau ecoregions could yield additional new state records. Developmental host and adult resource plants, collection methods, as well as regional collection notes from adjacent states are discussed for several additional candidate longhorned beetle species.

Pityopsis ruthii is a federally endangered plant, endemic to riparian areas of the Hiwassee and Ocoee rivers in southeastern Tennessee. The population size and spatial distribution of this species along the Ocoee River has been documented since 1985, yet about 90% of P. ruthii plants are recorded within a portion of the Hiwassee River. Our ongoing population census of these localities delineates 57 discrete site occurrences and constitutes the first population baseline for P. ruthii along the Hiwassee River. Evidence indicates that P. ruthii populations are either stable or increasing along the Ocoee River. Augmentation of natural flow and subsequent invasion of competing vegetation are frequently cited as a threat to the species; however, historical aerial photography suggests significant portions of P. ruthii habitat are resistant to succession. We discuss recent evidence that a number of natural and anthropogenic stressors are challenging population sustainability, including: invasive plants, ...

The digestive system of selected phytophagous insects has been examined as a potential prospecting resource for identification of novel cellulolytic enzymes with potential industrial applications. In contrast to other model species, however, limited detailed information is available that characterizes cellulolytic activity and systems in basal hexapod groups. As part of a screening effort to identify insects with highly active cellulolytic systems, we have for the first time, identified species of Zygentoma that displayed the highest relative cellulase activity levels when compared to all other tested insect groups under the experimental conditions, including model species for cellulolytic systems such as termite and cockroach species in Rhinotermitidae (formerly Isoptera) and Cryptocercidae (formerly Blattodea). The goal of the present study was to provide a morphohistological characterization of cellulose digestion and to identify highly active cellulase enzymes present in digestive fluids of Zygentoma species. Morphohistological characterization supported no relevant differences in the digestive system of firebrat (Thermobia domestica) and the gray silverfish (Ctenolepisma longicaudata). Quantitative and qualitative cellulase assays identified the foregut as the region with the highest levels of cellulase activity in both T. domestica and C. longicaudata. However, T. domestica was found to have higher endoglucanase, xylanase and pectinase activities compared to C. longicaudata. Using nano liquid chromatography coupled to tandem mass spectrometry (nanoLC/MS/MS) and a custom gut transcriptome we identified cellulolytic enzymes from digestive fluids of T. domestica. Among the identified enzymes we report putative endoglucanases matching to insect or arthropod enzymes and glucan endo-1,6-β-glucosidases matching bacterial enzymes. These findings support combined activities of endogenous and symbiont-derived plant cell wall degrading enzymes in lignocellulose digestion in Zygentoma and advance our understanding of cellulose digestion in a primitive insect group.

The sense of smell enables the detection and discrimination of airborne chemicals via chemosensory receptors that have evolved independently multiple times throughout the tree of life. In insects, the odorant receptor (OR) gene family is the major chemosensory gene family involved in olfaction and its origin has been hypothesized to coincide with the evolution of a terrestrial lifestyle in hexapods. Missbach et al. (2014) challenged this view and suggested that ORs evolved with an ancestral OR co-receptor (Orco) after the origin of terrestriality, hypothesizing that the OR/Orco system is an adaptation to winged flight in insects instead. Building upon this work, we investigated the genomes of basal hexapod and insect lineages including Collembola, Diplura, Archaeognatha, Zygentoma, Odonata, and Ephemeroptera in an effort to identify the origin of the insect OR gene family. While absent from all non-insect hexapod lineages analyzed, ORs are present in all insect genomes. Orco is absent only in the most ancient insect lineage Archaeognatha. A fully functional OR/Orco system was present in our newly generated genome data of the Zygentoma Thermobia domestica. We suggest that ORs did evolve as adaptation to a terrestrial lifestyle outside high-humidity habitats, and not winged flight, representing a key evolutionary novelty in the ancestor of all insects. The OR family is therefore the first known molecular synapomorphy for the Class Insecta.

Thousand cankers disease (TCD) is a pest complex formed by the association of the walnut twig beetle (WTB), Pityophthorus juglandis Blackman (Coleoptera: Curculionidae: Scolytinae), with the fungal pathogen Geosmithia morbida Kolařik, Freeland, Utley and Tisserat (Ascomycota: Hypocreales: Bionectriaceae). Current monitoring and detection efforts for WTB rely on a pheromone lure that is effective over a limited distance while plant- and fungal-derived volatiles that may facilitate host location remain poorly understood. In this study, we test the hypothesis that adult beetles are attracted to volatiles of black walnut, Juglans nigra L. (Juglandaceae), and the pathogen, G. morbida. We measured the response of beetles to head-space volatiles collected from leaves and stems of 12 genotypes of black walnut and found genotypic variation in the attractiveness of host trees to adult WTB. Volatile profiles of the most attractive genotypes contained more α-pinene and β-pinene, and adult beetles were attracted to both of these compounds in olfactometer bioassays. In bioassays, we also demonstrated that adult WTB are attracted to volatiles of G. morbida. These findings suggest that, in addition to the aggregation pheromone, dispersing WTB potentially use host plant and fungal volatiles to locate suitable larval hosts. Finally, we conducted a field experiment to determine the extent to which ethanol, a common attractant for bark beetles, and limonene, a known bark beetle repellent, influence the behavior of adult WTB to pheromone-baited traps. Although ethanol did not increase trap capture, WTB were repelled by limonene, suggesting that this compound could be used to manipulate and manage WTB populations.

Thousand Cankers Disease (TCD) of Juglans and Pterocarya (Juglandaceae) involves a fungal pathogen, Geosmithia morbida, and a primary insect vector, Pityophthorus juglandis. TCD was described originally from dying Juglans nigra trees in the western United States (USA), but it was reported subsequently from the eastern USA and northern Italy. The disease is often difficult to diagnose due to the absence of symptoms or signs on the bark surface of the host. Furthermore, disease symptoms can be confused with those caused by other biotic and abiotic agents. Thus, there is a critical need for a method for rapid detection of the pathogen and vector of TCD. Using species-specific microsatellite DNA markers, we developed a molecular protocol for the detection of G. morbida and P. juglandis. To demonstrate the utility of the method for delineating TCD quarantine zones, we tested whether geographical occurrence of symptoms and signs of TCD was correlated with molecular evidence for the presence of the cryptic TCD organisms. A total of 1600 drill cores were taken from branch sections collected from three regions (n = 40 trees for each location): California-J. hindsii (heavy disease incidence); Tennessee-J. nigra (mild disease incidence); and outside the known TCD zone (Missouri-J. nigra, no record of the disease). California samples had the highest incidence of the TCD organisms (85%, 34/40). Tennessee had intermediate incidence (42.5%, 17/40), whereas neither organism was detected in samples from Missouri. The low cost molecular protocol developed here has a high degree of sensitivity and specificity, and it significantly reduces sample-processing time, making the protocol a powerful tool for rapid detection of TCD.

Several North American walnut species (Juglans spp.) are threatened by thousand cankers disease which is caused by the walnut twig beetle (Pityophthorus juglandis Blackman) and its associated fungal plant pathogen, Geosmithia morbida M. Kolarík, E. Freeland, C. Utley and N. Tisserat sp. nov. Spread of this disease may occur via movement of infested black walnut (Juglans nigra L.) wood. This study evaluated the ability of P. juglandis to colonize J. nigra wood previously treated with various phytosanitation methods. Steam-heated and methyl bromide-fumigated J. nigra logs, as well as kiln-dried natural wane J. nigra lumber (with and without bark) were subsequently exposed to P. juglandis colonization pressure in two exposure scenarios. Following a pheromone-mediated, high-pressure scenario in the canopy of infested trees, beetles readily colonized the bark of steam-heated and methyl bromide-fumigated logs, and were also recovered from kiln-dried lumber on which a thin strip of bark was retained. In the simulated lumberyard exposure experiment, during which samples were exposed to lower P. juglandis populations, beetles were again recovered from bark-on steam-heated logs, but were not recovered from kiln-dried bark-on lumber. These data suggest logs and bark-on lumber treated with phytosanitation methods should not be subsequently exposed to P. juglandis populations. Further beetle exclusion efforts for phytosanitized, bark-on walnut wood products transported out of quarantined areas may be necessary to ensure that these products do not serve as a pathway for the spread of P. juglandis and thousand cankers disease.

The Chrysobothris femorata (Olivier) species group has expanded to 12 recognized species. Many of these species are sympatric, share larval host plants, and are difficult to reliably separate morphologically. This study investigated species limits and relationships among the recognized species occurring within the southeastern United States. Results are presented from phylogenetic analyses including several group members using sequences from cytochrome oxidase I (cox I) and arginine kinase (AK). Cox I analyses validated the monophyly of several Chrysobothris species outside of the C. femorata species group and recovered group members C. adelpha Harold, C. viridiceps Melsheimer, and C. wintu Wellso and Manley as monophyletic. However, cox I analyses yielded well supported nodes that rendered C. femorata Olivier, C. quadriimpressa Gory and Laporte, C. rugosiceps Melsheimer, and C. shawnee Wellso and Manley paraphyletic. AK sequences provided statistical support for monophyly of C. wintu and two well supported clades that rendered C. femorata and C. quadriimpressa paraphyletic. Imperfect taxonomy cannot totally account for this phenomenon. The observed pattern could be the result of ancestral polymorphism or lineage sorting, yet introgression of these C. femorata species group members is possible. Although observed results from these genes suggest potential taxonomic synonymization, such steps are premature. Greater understanding of interactions between group members as occurs within their overlapping geographies and host plants is needed. We suggest future molecular studies adopting a population genetics approach utilizing several nuclear genes or SNiPs acquired subsequent to a NextGen sequencing campaign.

Distribution records and seasonal flight activity information for metallic woodboring beetle (Coleoptera: Buprestidae) species have not been com piled for North Carolina and Tennessee. Institutional, research, and private collections in North Carolina and Tennessee were reviewed to provide seasonal activity data of 5 subfamilies of buprestid beetle species. Label information was checked for 15,217 specimens of 135 species collected between 1901 and 2013 (North Carolina) and between 1934 and 2013 (Tennessee). These collections provided data on adult seasonal activity and county records for 121 species (4,467 specimens) and 105 species (10,750 specimens) from North Carolina and Tennessee, respectively. Two species, Agrilus carpini Knull and A. pensus Horn, are reported as New State Records for North Carolina. The data reveal key geographic areas in both states where few to no collections have been made, highlighting opportunities to validate species distributions and locations where future collecting ef forts can be matched with the occurrence of larval and adult host plant resources. Seasonal activity records will inform future biosurveillance efforts for invasive and endemic pests and facilitate predictions of buprestid species that are likely to be active within the hunting flight season of Cerceris fumipennis (Say) (Hymenoptera: Crabronidae) wasps. Activity periods of the buprestids also can focus the management of selected economic pest species to times of the year when treatment efforts, particularly through use of contact insecticides, are likely to be most effective.

The genus Vaccinium represents an increasingly important group of plants for the U.S. green industry. In 2012, blueberries (Vaccinium sp.) ranked the second most important berry crop in the U.S. with a total crop value over $780 million. The popularity of blueberries creates opportunities as well as challenges for nursery crop producers. This article presents a review of current nursery production practices of blueberry and explores the challenges and opportunities for nursery crop producers, including pesticide use during nursery production of an edible crop, and discusses current research relevant to the green industry. Needs for additional research and opportunities for breeding are presented. Blueberries are Ericaceous plants and have very specific cultural requirements. This review presents the culture, as well as insect, mite, and disease control from an integrated pest management (IPM) approach for several blueberry species. A serious threat to the blueberry market, spotted wing drosophila (Drosophila suzukii Matsumura) is discussed to provide information needed by commercial producers and landscape managers to address client and customer questions. This review also highlights the most relevant blueberry selections for container production in the southeastern United States.

Chemical pesticides can efficiently control insect pests and are often relied upon by nursery producers. With increased consumer concerns regarding insecticides, growers may choose to limit insecticide applications by incorporating natural enemies into their pest management program. This study assessed the effects of commonly used contact (bifenthrin and carbaryl) and systemic (imidacloprid and dinotefuran) insecticides on adult Chrysoperla rufilabris (Burmeister), adult Hippodamia convergens (Guerin-Meneville), and adult Orius insidiosus (Say) to evaluate their safety for use with natural enemies. Insects were confined in experimental arenas either with leaves sprayed to provide insecticide residues or leaves treated with only water and then air-dried prior to use. Both systemic and contact insecticides caused mortality in all three insect species. The contact insecticide bifenthrin was the least toxic to C. rufilabris, and the systemic insecticide, dinotefuran, was not toxic to H. convergens. ...

Thousand cankers disease, caused by the invasive bark beetle Pityophthorus juglandis Blackman and an associated fungal pathogen Geosmithia morbida M.Kolařík, E. Freeland, C. Utley, N. Tisserat, currently threatens the health of eastern black walnut (Juglans nigra L.) in North America. Both the beetle and pathogen have expanded beyond their native range via transport of infested walnut wood. Geosmithia morbida can develop in seedlings following inoculation, but the ability of P. juglandis to colonize young, small diameter trees has not been investigated. This study assessed the beetle's colonization behavior on J. nigra nursery trees. Beetles were caged directly onto the stems of walnut seedlings from five nursery sources representing a range of basal stem diameter classes. Seedlings were also exposed to P. juglandis in a limited choice, field-based experiment comparing pheromone-baited and unbaited stems. When beetles were caged directly onto stems, they probed and attempted to colonize seedlings across the range of diameters and across sources tested, including stems as small as 0.5 cm in diameter. In the field experiment, beetles only attempted to colonize seedlings that were baited with a pheromone lure and appeared to prefer (though not statistically significant) the larger diameter trees. Despite several successful penetrations into the phloem, there was no evidence of successful progeny development within the young trees in either experiment. Further investigation is recommended to better elucidate the risk nursery stock poses as a pathway for thousand cankers disease causal organisms.

Mugwort (Artemisia vulgaris) is a perennial invasive weed species that has infiltrated row crops, turfgrass, ornamentals, and various noncrop areas. Currently, multiple mimics of indole-3-acetic acid can provide control of this species; however, these herbicides can damage certain sensitive ornamental plants. When applied at reduced rates, the p-hydroxyphenylpyruvate dioxygenase (HPPD)-inhibiting herbicides mesotrione and topramezone have demonstrated some selectivity among certain ornamental plants. Field and greenhouse studies were initiated to evaluate whether these herbicides could control mugwort when applied alone, or in mixtures with photosystem II (PSII)-inhibiting herbicides that often provide synergistic weed control. In the field, mesotrione controlled mugwort between 30% and 60% by 21 days after treatment when applied at 0.093 to 0.187 lb/acre. When the PSII-inhibiting herbicide atrazine was added, control increased to 78% and 79%. In the greenhouse, similar rates produced greater control in mugwort, and all mesotrione treatments limited mugwort regrowth by at least 95% when compared with untreated control. When HPPD inhibitor rates were reduced further, the addition of the PSII inhibitors atrazine or bentazon was not sufficient at providing acceptable control of mugwort.

The genus Viburnum encompasses a group of about 150 species of evergreen, semi-evergreen or deciduous trees and large shrubs. Viburnums are native to temperate, subtropical and tropical areas of southeastern Asia, eastern North America, Central America, the Caribbean and parts of South America. Native and nonnative Viburnum species have become prominent landscape plants in the southeastern United States due to their beauty, utility, relative ease of maintenance and broad adaptability to the region's climate and soils. Efficient management of viburnum pests to maintain healthy viburnum plants in nurseries and landscape settings is crucial for sustaining the economic competitiveness and profitability of green industry professionals competing in the horticulture marketplace. Diversity of species within the genus, however, is vast, and can contribute to many host-pest complexes that differ among growing environments and cause severe economic or aesthetic losses. Additionally, some abiotic disorders may mimic biotic damage or may render viburnum more susceptible to pests and diseases. This review focuses on viburnum culture in production and landscape settings with an emphasis on major insect and mite pests, plant diseases and abiotic disorders affecting management of Viburnum species in nursery and landscape settings.

Sciadopitys verticillata (Sv) produces a white, sticky, latex-like resin with antimicrobial properties. The aims of this research were to evaluate the effects of this resin (Sv resin) on bacterial populations and to determine the impact of its primary volatile components on bioactivity. The impact of sample treatment on chemical composition of Sv resin was analyzed using Fourier transform infrared spectroscopy (FTIR) coupled with principal component analysis. The presence and concentration of volatiles in lyophilized resin were determined using gas chromatography/mass spectrometry (GC/MS). Changes in bacterial population counts due to treatment with resin or its primary volatile components were monitored. Autoclaving of the samples did not affect the FTIR spectra of Sv resin, however, lyophilization altered spectra, mainly in the CH and C=O regions. Three primary bioactive compounds that constituted &gt, 90% of volatiles (1R-&alpha, pinene, tricyclene, and &beta, pinene) were identified in Sv resin. Autoclaved resin impacted bacterial growth. The resin was stimulatory for some plant and foodborne pathogens (Pseudomonas fluorescens, P. syringae, and Xanthomonas perforans) and antimicrobial for others (Escherichia coli, Bacillus cereus, Agrobacterium tumefaciens, and Erwinia amylovora). Treatment with either 1R-&alpha, pinene or &beta, pinene reduced B. cereus population growth less than did autoclaved resin. The complex resin likely contains additional antimicrobial compounds that act synergistically to inhibit bacterial growth.

Insects are a largely unexploited resource in prospecting for novel cellulolytic enzymes to improve the production of ethanol fuel from lignocellulosic biomass. The cost of lignocellulosic ethanol production is expected to decrease by the combination of cellulose degradation (saccharification) and fermentation of the resulting glucose to ethanol in a single process, catalyzed by the yeast Saccharomyces cerevisiae transformed to express efficient cellulases. While S. cerevisiae is an established heterologous expression system, there are no available data on the functional expression of insect cellulolytic enzymes for this species. To address this knowledge gap, S. cerevisiae was transformed to express the full-length cDNA encoding an endoglucanase from the red flour beetle, Tribolium castaneum (TcEG1), and evaluated the activity of the transgenic product (rTcEG1). Expression of the TcEG1 cDNA in S. cerevisiae was under control of the strong glyceraldehyde-3 phosphate dehydrogenase promoter. Cultured transformed yeast secreted rTcEG1 protein as a functional β-1,4-endoglucanase, which allowed transformants to survive on selective media containing cellulose as the only available carbon source. Evaluation of substrate specificity for secreted rTcEG1 demonstrated endoglucanase activity, although some activity was also detected against complex cellulose substrates. Potentially relevant to uses in biofuel production rTcEG1 activity increased with pH conditions, with the highest activity detected at pH 12. Our results demonstrate the potential for functional production of an insect cellulase in S. cerevisiae and confirm the stability of rTcEG1 activity in strong alkaline environments.

Autumn olive (Elaeagnus umbellata) poses significant challenges for forest managers. The ability to predict when and where this species will become a problem would allow managers to more effectively prioritize control efforts and implement the most efficient management practices available. Several studies have sought to determine which key factors lead to greater abundance of exotic, invasive plants on certain sites and their spread at multiple scales. Previous research suggests that disturbances and increased light can be important. The overall goal of this research was to identify factors associated with forest road edges that are most important in facilitating autumn olive. Specific objectives were to: (1) document site factors significantly related to the presence and success of autumn olive, (2) investigate the hypothesis that southern aspects have greater abundance, patch depth and growth of autumn olive than other aspects, (3) examine the hypothesis that there is a negative relationship between the abundance and height of autumn olive and the abundance and height of native species, and (4) determine if the relationship between autumn olive abundance and height and the abundance and height of other invasive species is positive. Densities of autumn olive, native woody species, and other woody exotic, invasive species in different size classes were quantified in plots located along forest-road edges having northern, southern, eastern, and western aspects. Slopes, elevation, road opening width, canopy cover, and basal area were also quantified at each plot location. In addition, presence and absence of autumn olive, slope, elevation, canopy cover, and road canopy closure were quantified at randomly selected points along major and minor gravel roads within the study area. Larger autumn olive were most abundant along edges with southern aspects and patches of autumn olive were deepest on edges with northern and southern aspects. Autumn olive height and abundance were positively related to the height and abundance of both native and exotic, invasive woody plants. Slope, elevation, road canopy cover, road opening width, and road type were found to be important factors influencing autumn olive establishment and success. As a result, these factors may prove useful in the development of habitat suitability models and GIS-based risk maps that managers could use to more effectively address this invasive species.

With increased mobile device usage, mobile applications (apps) are emerging as an extension medium, well suited to “place-less” knowledge transfer. Conceptualizing, designing, and developing an app can be a daunting process. This article summarizes the considerations and steps that must be taken to successfully develop an app and is based on the authors’ experience developing two horticulture apps, IPMPro and IPMLite. These apps provide information for major pests and plant care tasks and prompt users to take action on time-sensitive tasks with push notifications scheduled specifically for their location. Topics such as selecting between a web app and a native app, choosing the platform(s) for native apps, and designing the user interface are covered. Whether to charge to download the app or have free access, and navigating the intra- and interinstitutional agreements and programming contract are also discussed. Lastly, the nonprogramming costs such as creating, editing, and uploading content, as well as ongoing app management and updates are discussed.

Mobile device applications (apps) have the potential to become a mainstream delivery method, providing services, information, and tools to extension clientele. Testing, promoting, and launching an app are key components supporting the successful development of this new technology. This article summarizes the considerations and steps that must be taken to successfully test, promote, and launch an app and is based on the authors’ experience developing two horticulture apps, IPMPro and IPMLite. These apps provide information for major pests and plant care tasks and prompt users to take action on time-sensitive tasks with push notifications scheduled specifically for their location. App testing and evaluation is a continual process. Effective tactics for app testing and evaluation include garnering focus group input throughout app development and postlaunch, in-house testing with simulators, beta testing and the advantages of services that enhance information gained during beta testing, and postlaunch evaluations. Differences in promotional and bulk purchasing options available among the two main device platforms, Android and iOS, are explored as are general preparations for marketing the launch of a new app. Finally, navigating the app submission process is discussed. Creating an app is an involved process, but one that can be rewarding and lead to a unique portal for extension clientele to access information, assistance, and tools.