Location: Emerging Pests and Pathogens Research
Project Number: 8062-22410-007-00-D
Project Type: In-House Appropriated
Start Date: Oct 1, 2020
End Date: Feb 28, 2025
Objective 1. Curate and expand the ARSEF for research, industrial and commercial uses. [NP304, C1, PS 1C; C3, PS 3B] Sub-objective 1.1 Continue the curation, operation, and expansion of the ARSEF culture collection and associated information resources. Sub-objective 1.2 Improve methods to isolate, culture, and preserve fungal entomopathogens. Sub-objective 1.3 Conduct research on the taxonomy, systematics, organismal biology, and population genetics of entomopathogenic fungi. Objective 2. Identify genetic, molecular, ecological, and environmental factors that are associated with a) plant maladies such as rapid apple decline, citrus greening and cotton blue disease; b) arthropod-host interactions, such as ambrosia beetles, psyllids and aphids; and c) arthropod-borne plant pathogen-vector interactions such as Liberibacter and poleroviruses using advanced molecular approaches. [NP304, C3, PS 3A and 3B] Sub-objective 2.1 Identify pathogen, host, and vector components that regulate uptake and transmission of plant pathogens by sap-sucking insects. Sub-objective 2.2 Carry out functional analysis of genes, proteins and metabolites involved in plant pathogen transmission. Sub-objective 2.3 Identify pathogen and host components that regulate entomopathogen infection. Sub-objective 2.4 Document biology and phenology of ambrosia beetles. Sub-objective 2.5 Test for an association of insects and plant pathogens with rapid apple decline. Objective 3. Develop methods using novel interdiction molecules (RNAi, RNA aptamers, siderophores, antimicrobial peptides, modified insect neuropeptides, entomopathogenic fungi) that may interfere with vector-pathogen-host interactions. [NP304, C3, PS 3B] Sub-objective 3.1 Develop a new tool to block aphid transmission of poleroviruses. Sub-objective 3.2 Develop RNA aptamers that bind to transmission-related compounds and test their ability to interfere with pathogen acquisition and transmission. Sub-objective 3.3 Test the utility of plant, insect and microbial derived proteins, peptides and metabolites for control of vector borne diseases. Sub-objective 3.4 Test entomopathogens against the ambrosia beetle. Sub-objective 3.5 Identify RNAi targets for ambrosia beetle control.
Symbiotic interactions between arthropods and microbes span a continuum where mutualism and pathogenesis represent the extremes. Microbial associations with arthropods can be extracellular or intracellular. A subset of arthropod-associated microbes is pathogenic to plants and animals. Many serious plant and animal pathogens are dependent upon arthropod vectors for transmission between hosts. Targeting the relationships between arthropods and microbes is a major focus of research to manage arthropods and arthropod-borne plant diseases. Control of arthropods and arthropod vectors that transmit pathogens is arguably one of the biggest challenges to human health and agriculture. Our experimental systems offer innovative approaches to study and manage arthropods and arthropod-borne plant diseases that have been recalcitrant to the development of host resistance and for which the economic and environmental costs of control has been prohibitive, unsustainable and/or ineffective. Scientists' incomplete understanding of interactions among arthropods, plant associated microbes (including plant pathogens) and plant hosts limits the development of new tools to block or interfere with pathogen transmission by arthropods in the field. We address this problem by investigating the ecological and molecular interactions that mediate these associations. New technologies and knowledge from the planned research are expected to be extended to the study of other arthropod-microbe interactions and will greatly impact growers, industry stakeholders, and other research communities. The project will also focus on maintaining the extensive ARS Collection of Entomopathogenic Fungal Cultures (ARSEF). ARSEF is a central tool for research in the project and the entire scientific community. It contains 14,342 isolates representing 721 fungal taxa from over 1,300 arthropod hosts (representing major insect orders) in 112 countries. It will be managed to ensure ongoing accession, preservation, identification, and distribution of fungal isolates for the development and deployment as biocontrol agents and for research purposes. The ARSEF also plays a central role in revising taxonomies of fungi using state-of-the-art systematic methods.