Location: National Peanut Research Laboratory
Project Number: 6044-21000-005-000-D
Project Type: In-House Appropriated
Start Date: Jul 30, 2018
End Date: Jul 29, 2023
Objective:
Objective 1. Characterize peanut pathogens, host responses, and host-plant interactions, including diversity of plant invasion and plant health genes, and use genomic and transcriptomic knowledge for discovery and development of novel methods or technologies to control diseases.
Objective 2. Identify, characterize, and evaluate peanut genes involved in disease resistance and drought tolerance, including discovery and elucidation of agriculturally-relevant candidate genes, and work with breeders to facilitate implementation into breeding programs.
Objective 3: Conduct research to develop and assay novel high-throughput pre-harvest aflatoxin resistance screening methods, identify genes, and determine their functions and expression, develop molecular markers with mapping populations, and work with breeders to develop aflatoxin-resistant peanut varieties. (NP 301, C1, PS1A and PS1B).
Objective 4. Determine the physiological mechanisms that link Aspergillus infection with aflatoxin contamination (NP 303, C2, PS 2A).
Objective 5. Understanding the pathway in aspergillus invasion (collaborative effort with FVSU utilizing their scanning electron microscope abilities to understand changes in hull structure under varying environmental conditions), determine impact of Laccase enzymes on hull degradation (NP 303, C2, PS 2A).
Objective 6. Work with breeders to develop varieties with resistance to aflatoxin (NP 301 C1, PS 1A).
Approach:
Double strand RNA (dsRNA) that targets aflatoxin synthesis can be used as a therapeutic control of mycotoxins in peanut without genetic transformation. Knowing the genetic makeup of peanut pathogens (Cercospora arachidicola, Cercosporidium personatum, Thecaphora frezzi, Aspergillus (A.) niger, A. flavus and A. parasiticus) allows for a better disease management and longer effectiveness of control. Identification and validation of molecular markers associated with biotic (early and late leaf spot, peanut smut, crown rot disease, mycotoxin producing fungi), and abiotic (drought) stress resistance in wild peanuts and land races will accelerate breeding programs. Analysis and non-GMO manipulation of gene expression, physiology, microRNA expression, and changes in methylation patterns, both of the plant seed as of Aspergillus during the process of infection, can point to resistance genes or other desirable seed response relevant to the control of aflatoxins. Aspergillus Laccase enzymes are a potentially important factor in pathogenicity, studying the activity of these enzymes on hull degradation/penetration in relation to the varying composition of hulls depending on cultivar and maturity, can lead to develop tools to interfere/block the action of laccases and hence seed invasion by Aspergillus, this work will incorporate the assistance of Scientists in our Unit who have expertise in mechanical resistance of hulls. Collaborating with other research projects in our Unit, we will provide the infrastructure support for large scale screening of germplasm to be incorporated in our pre-breeding program.
