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Informed and effective management of emerging infectious diseases can be improved by a clear understanding of host–pathogen–environment interactions. Impacts of the seasonal environment on pathogen dynamics and host responses are poorly described in most reptile host–fungal pathogen systems. Here, we describe seasonal patterns of ophidiomycosis, a disease caused by the fungus Ophidiomyces ophidiicola (Oo), in a population of pygmy rattlesnakes, Sistrurus miliarius, in central Florida. We used field observations of gross clinical signs of disease in combination with qPCR on skin swabs to examine the seasonal prevalence of Oo and patterns of clinical presentation in hosts. We monitored thermoregulatory behaviors, ecdysis, and reproductive status in free‐living snakes to examine seasonal associations between infection and host coping responses. Both the prevalence of Oo and clinical signs of disease varied strongly with the season (winter high and summer low). In both seasons, the presence of clinical signs was a strong predictor of the presence of Oo as identified by qPCR on skin swabs (78% probability across seasons). Snakes with clinical signs of disease were more likely to be observed exhibiting thermoregulatory behavior or in ecdysis compared to non‐clinical snakes across seasons. The prevalence of Oo was not significantly different in pregnant snakes compared to other reproductive categories, but pregnant females were less likely to exhibit clinical signs of disease compared to males. Our results highlight strong seasonal patterns in both host clinical signs and Oo prevalence and support the efficacy of using gross clinical signs of disease in combination with qPCR on skin swabs to assess disease dynamics in free‐living snakes. We also identify ecdysis and thermoregulatory behaviors as components of the seasonal disease‐coping response and highlight the need to examine these behaviors as potential drivers of seasonal infection outcomes in reptiles afflicted with fungal pathogens. [ABSTRACT FROM AUTHOR]

Mass rearing herbivorous insects used as biological control agents requires a steady supply of optimal host plant material. This often necessitates the use of pesticides to minimise infestations and damage from generalist herbivores. Knowing the efficacy persistence of the pesticide is critical to prevent non-target effects on reared agent populations. We determined the amount of time for an abamectin foliar spray to degrade such that there were minimal impacts on the mass rearing of Pseudophilothrips ichini (Hood), a biological control agent for Brazilian peppertree (Schinus terebinthifolia Raddi) in Florida. Abamectin was applied to plants at the label concentration (0.31 ml/L) for controlling mites. Groups of three plants were brought into our quarantine facility 1, 3, 7, 10, and 14 d after application and were then each infested with 40 founding adult thrips. Founding adult survival was not impacted by the delay, i.e. interval between application and thrips infestation, with at least 75% recovered alive regardless of the delay. However, delaying infestation had a significant effect on the number of offspring produced, with, on average, only 50 produced when waiting 1 d, between 250 and 364 for the intermediate wait times, and 688 produced when waiting 14 d. Waiting 14 d after treatment before infesting new plants would achieve optimal colony yields but waiting as little as 7 d may still be a reasonable balance between timely production operations and colony yields. Those developing insect mass rearing programmes should consider all variables specific to their procedures that may impact pesticide persistence. [ABSTRACT FROM AUTHOR]

Abstract: Short term exposure of Vallisneria americana to elevated salinity was found to induce a stress response that could be quantified by a series of metabolic assays measuring oxidative stress, photosynthetic efficiency, and dark adapted respiration. Plant specimens exposed to elevated salinity for 24h displayed signs of oxidative damage represented by the accumulation of reactive oxygen species (ROS) and lipid hydroperoxides in blade tissue (noted at salinities of 10 and 15, respectively). Respiratory demand nearly doubled (140 nanomoles O2 consumed min−1 g−1) when plants were placed in a salinity of 15 for 24h versus control specimens maintained at 0. After 1 week of exposure a significant increase in respiration and lipid hydroperoxide content was detected in plants incubated at or above a salinity of 13. In addition, effective quantum yield () dropped significantly compared to plants maintained at a salinity below 13. These results highlight the use of cellular stress assays to monitor salt-induced sublethal responses in V. americana. [Copyright &y& Elsevier]

Damage by Euxesta stigmatias Loew larvae to sweet corn renders the ears unmarketable. This report evaluates the efficacy of insecticides labeled for armyworm control in Florida sweet corn against E. stigmatias adults. Tests were performed in controlled settings by using direct contact and dried plant residues of esfenvalerate, cyfluthrin, lambda-cyhalothrin, chlorpyrifos, methyl parathion, methomyl, and thiodicarb. Direct application of all insecticides except thiodicarb quickly killed or caused incapacitating sublethal affects (uncoordinated movement, uncontrolled twitching, and hyperextension of mouthparts and ovipositor) to > 75% of the flies. Low rates (0.56 kg [All/ha) of chlorpyrifos and methyl parathion provided the most efficient control, killing 100 and 93%, respectively, within 2 h of direct contact. Low rates of pyrethroids induced low mortality but high sublethal effects that together immobilized nearly 100% of adults within 1 h of exposure. Mortality reached 95% within 2 h of direct contact in flies treated with high rates of pyrethroids. Methomyl killed as many as 94%, but required 24 h to reach this level after direct treatment. Residues on dipped leaves and field-treated plants of all tested insecticides except methyl parathion were less effective at killing adults compared with direct contact tests. Pyrethroid residues (particularly cyfluthrin) on field planted sweet corn induced significantly higher levels of sublethal effects (57-70%), and for a longer period of time, compared with materials in the other classes of chemistry. [ABSTRACT FROM AUTHOR]