Leaf-cutting ants learn to avoid plants initially harvested if they prove to be harmful for their symbiotic fungus once incorporated into the nest. At this point, waste particles removed from the fungus garden are likely to contain cues originating from both the unsuitable plant and the damaged fungus. We investigated whether leaf-cutting ant foragers learn to avoid unsuitable plants solely thr...

The use of fungicides in crop protection still effectively eliminates fungal pathogens of plants. However, fungicides may dissipate to various elements of the environment and cause irreversible changes. Considering this problem, the aim of the presented study was to evaluate changes in soil biological activity in response to contamination with azoxystrobin. The study was carried out in the labo...

IN 1996, the U.S. Congress unanimously passed the Food Quality Protection Act (FQPA). Among other things, the law formalized the U.S. Environmental Protection Agency’s (EPA) Reduced-Risk Pesticide Program (initiated in 1993) and mandated that EPA continue to enhance it (EPA 2003, 2004). The FQPA expedited EPA’s review and registration decision-making process for pesticides that are classified a...

Knowledge of the evolution of fungicide resistance is important in securing sustainable disease management in agricultural systems. In this study, we analyzed and compared the spatial distribution of genetic variation in azoxystrobin sensitivity and SSR markers in 140 Phytophthora infestans isolates sampled from seven geographic locations in China. Sensitivity to azoxystrobin and its genetic va...

Chemical management of dollar spot in turf may lead to the development of Sclerotinia homoeocarpa populations with reduced fungicide sensitivity. The objective of this study was to investigate resistance of S. homoeocarpa isolates to triazole fungicides and to test cross-resistance among three triazole fungicides. A total of 66 isolates of S. homoeocarpa were collected from 15 golf courses acro...

A common consequence of using agricultural fungicides is the development of resistance by fungal pathogens, which undermines reliability of fungicidal effectiveness. A potentially new strategy to aid in overcoming or minimizing this problem is enhancement of pathogen sensitivity to fungicides, or "chemosensitization." Chemosensitization can be accomplished by combining a commercial fungicide wi...

Title of Document: INTEGRATED PEST MANAGEMENT OF FUSARIUM HEAD BLIGHT IN SOFT RED WINTER WHEAT. Elizabeth Reed, M.S., 2011 Directed By: Associate Professor Arvydas Grybauskas, Department of Plant Sciences and Landscape Architecture Fusarium head blight (FHB), caused by Fusarium graminearum, is a destructive disease of the soft red winter wheat grown in the Mid-Atlantic region. Management of FHB...

Defining appropriate policies for controlling the spread of fungal disease in agricultural landscapes requires appropriate theoretical models. Most existing models for the fungicidal control of plant diseases do not explicitly include the dynamics of the fungicide itself, nor do they consider the impact of infection occurring during the host growth phase. We introduce a modelling framework for ...

Arbuscular mycorrhizal fungi (AMF) are critical links in plant-soil continuum and play a critical role in soil carbon cycles. Soil respiration, one of the largest carbon fluxes in global carbon cycle, is sensitive to precipitation change in semiarid ecosystems. In this study, a field experiment with fungicide application and water addition was conducted during 2010-2013 in a semiarid steppe in ...

The late blight disease caused by the fungus Phytophthora infestans is a serious pest of solanaceous crops capable of destroying a complete harvest. Therefore it is heavily treated with fungicides, especially in areas where the knowledge among farmers about application and impacts of fungicides is generally low, as it is the case in Nepal. In order to derive efficient treatment strategies with ...