First Report of Melon Severe Mosaic Orthotospovirus infecting cucurbits in the United States.

Cucurbits (family Cucurbitaceae) includes globally important fruit and vegetable crops. Virus diseases pose a serious threat to cucurbits, limiting crop quality and yield (Regina et al. 2021). In fall 2023, leaf and fruit samples from two squash plants with chlorotic mosaic symptoms and fruit distortion from Monroe and Pope counties in Arkansas were received for diagnosis at the University of Arkansas Division of Agriculture Plant Clinic. Based on symptoms, samples were assessed for melon severe mosaic orthotospovirus (MeSMV) using the ImmunoStrip® developed for detection of the virus (Agdia® Inc., Elkhart, Indiana). The presence of MeSMV was also confirmed by RT-PCR using the Agdia Tospovirus group PCR primers. An amplicon was sequenced and showed 91% sequence identity to the MESMV type isolate (NC_033834, VE440-A). To further verify the results, nucleic acids from a squash sample from Pope County were extracted as described by Poudel et al. (2013), DNase treated, and sequenced on an Oxford Nanopore MinION as described by Liefting et al. (2021). A total of 25,914 raw reads were analyzed using VirFind (Ho and Tzanetakis 2014), which identified 112 reads mapping to the three segments of MeSMV. Primers for all three RNAs were developed and amplified 638, 650, and 1153 nt of the S, M, and L segments of the virus respectively. The amplicons were sequenced bidirectionally and show 89-93% identity to the type isolate from Mexico (GenBank accessions PP301332-4). MeSMV has only been identified in Mexico and can cause significant losses to honeydew melon, zucchini, and cucumber (Ciuffo et al. 2009). Thus, this is the first report of MeSMV outside Mexico. Given the severity of the symptoms observed in cucurbit crops, the virus poses a potential threat to the cucurbit industry in the United States. Growers should be aware of this virus and take the necessary precautions to prevent its spread in the field.

A Workflow for Identifying Metabolically Active Chemicals to Complement in vitro Toxicity Screening.

The new paradigm of toxicity testing approaches involves rapid screening of thousands of chemicals across hundreds of biological targets through use of in vitro assays. Such assays may lead to false negatives when the complex metabolic processes that render a chemical bioactive in a living system are unable to be replicated in an in vitro environment. In the current study, a workflow is presented for complementing in vitro testing results with in silico and in vitro techniques to identify inactive parents that may produce active metabolites. A case study applying this workflow involved investigating the influence of metabolism for over 1,400 chemicals considered inactive across18 in vitro assays related to the estrogen receptor (ER) pathway. Over 7,500 first-generation and second-generation metabolites were generated for these in vitro inactive chemicals using an in silico software program. Next, a consensus model comprised of four individual quantitative structure activity relationship (QSAR) models was used to predict ER-binding activity for each of the metabolites. Binding activity was predicted for ~8-10% of metabolites in each generation, with these metabolites linked to 259 in vitro inactive parent chemicals. Metabolites were enriched in substructures consisting of alcohol, aromatic, and phenol bonds relative to their inactive parent chemicals, suggesting these features are potentially favorable for ER-binding. The workflow presented here can be used to identify parent chemicals that can be potentially bioactive, to aid confidence in high throughput risk screening.

Using exposure prediction tools to link exposure and dosimetry for risk-based decisions: A case study with phthalates.

A few different exposure prediction tools were evaluated for use in the new in vitro-based safety assessment paradigm using di-2-ethylhexyl phthalate (DEHP) and dibutyl phthalate (DnBP) as case compounds. Daily intake of each phthalate was estimated using both high-throughput (HT) prediction models such as the HT Stochastic Human Exposure and Dose Simulation model (SHEDS-HT) and the ExpoCast heuristic model and non-HT approaches based on chemical specific exposure estimations in the environment in conjunction with human exposure factors. Reverse dosimetry was performed using a published physiologically based pharmacokinetic (PBPK) model for phthalates and their metabolites to provide a comparison point. Daily intakes of DEHP and DnBP were estimated based on the urinary concentrations of their respective monoesters, mono-2-ethylhexyl phthalate (MEHP) and monobutyl phthalate (MnBP), reported in NHANES (2011-2012). The PBPK-reverse dosimetry estimated daily intakes at the 50th and 95th percentiles were 0.68 and 9.58 µg/kg/d and 0.089 and 0.68 µg/kg/d for DEHP and DnBP, respectively. For DEHP, the estimated median from PBPK-reverse dosimetry was about 3.6-fold higher than the ExpoCast estimate (0.68 and 0.18 µg/kg/d, respectively). For DnBP, the estimated median was similar to that predicted by ExpoCast (0.089 and 0.094 µg/kg/d, respectively). The SHEDS-HT prediction of DnBP intake from consumer product pathways alone was higher at 0.67 µg/kg/d. The PBPK-reverse dosimetry-estimated median intake of DEHP and DnBP was comparable to values previously reported for US populations. These comparisons provide insights into establishing criteria for selecting appropriate exposure prediction tools for use in an integrated modeling platform to link exposure to health effects.

Inheritance of resistance to Phomopsis seed decay in PI 360841 soybean.

Phomopsis longicolla Hobbs is the primary cause of Phomopsis seed decay (PSD) in soybean. Infection may result in moldy seed and poor germination. The objective of this study was to conduct inheritance studies to characterize resistance to PSD in plant introduction (PI) 360481. Crosses were made between PI 360841 and 2 PSD-susceptible genotypes, Agripro (AP) 350 and PI 91113, to determine the number of genes for resistance. Additionally, crosses were made between PI 360841 and Phomopsis resistant parents MO/PSD-0259 and PI 80837 to test the allelism of the resistance genes. Seed infection assays were done using seed from parent plants and F(2) populations. Chi-square analysis of the resistant x susceptible F(2) data fit to a 9R:7S model for 2 complementary dominant genes conferring PSD resistance in PI 360841. Segregation for reaction in the F(2) of MO/PSD-0259 x PI 360841 exhibited a good fit to a 57R:7S model for 2 complementary dominant genes from PI 360841 and a different dominant gene from MO/PSD-0259. There was no apparent segregation in the F(2) population from PI 360841 x PI 80837 except for one suspicious susceptible plant, suggesting one of the genes in PI 360841 is the same gene in PI 80837 for PSD resistance.

Primary process and peer consultation: an experiential model to work through countertransference.

Various models exist for peer supervision and consultation of group therapy. This article documents the authors' experience using an experiential group consultation of group therapy model that relies on primary process to overcome countertransference dilemmas. A review of group therapy supervision and consultation models is followed by vignettes from the authors' experience. Discussion of the vignettes highlight critical issues in group consultation and expound upon the strengths and challenges of using an experiential model.