Location: Crop Production and Protection
Project Number: 0500-00102-001-039-S
Project Type: Non-Assistance Cooperative Agreement
Start Date: Jun 1, 2024
End Date: May 31, 2025
Objective:
The overall objective of this project is work collaboratively to develop prediction tools for diseases and mycotoxins affecting corn to better inform management decisions.
Approach:
The project goals are conducted in four objectives: 1) Establish the association between inoculum intensity, production factors, disease development and weather in experimental plot trials; 2) Compare spore trap technologies for detection of pathogen population levels; 3) Develop primers and protocols for detection of the southern rust and Curvularia leaf spot pathogens; and 4) Disseminate corn disease information and management techniques through various outputs. In order to achieve objective, the work will focus on the following diseases: northern corn leaf blight (NCLB), gray leaf spot (GLS), southern rust (SR), Curvularia leaf spot (CLS), and Gibberella ear rot (GER). Experimental plot trials will be established in corn fields at two locations in Wisconsin to investigate associations among disease (GLS, NCLB, SR, CLS and GER) intensity and the following factors: (1) crop residue cover (initial inoculum), (2) fungicide application at VT/R1, (3) genetic resistance, and (4) airborne inoculum density. For crop residue cover, one field block will be no-tilled while another nearby field block will be tilled to remove crop residue, generating high (>80% residue cover) and low (<20% residue cover) surface residue treatments and consequently different initial inoculum amounts. Spore traps will be placed in the center of each field to monitor airborne inoculum density. Corn residue samples, consisting of 4-6 pieces of leaves and leaf sheaths, will be collected at 20 approximately equally spaced points along the line transect method described above (5 samples per transect) and bulked into a single composite sample per field. Samples will be air-dried as needed, weighed and sent to a cooperator for DNA extraction and qPCR analysis for pathogen identification. Disease ratings will be assessed bi-weekly. In order to achieve objective 3, primers specific for Puccinia polysora (SR) and Cuvularia lunata (CLS) will be designed based on sequence data available in a public genebank. Q-PCR protocols will be developed and optimized for use by a cooperator to detect pathogens in sample vials and on slides collected from the spore traps deployed at each location. In order to achieve objective 4, data collected from the trials described under objective 1 will be shared at field days throughout the growing season and workshops during the winter. Data on estimated yield losses due to disease will be contributed to a disease loss calculator. Corn disease management content for national and local websites will be developed.
