Location: Crop Production and Protection
Project Number: 0500-00102-001-036-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 to develop and validate disease and mycotoxin prediction tools to maximize the efficacy of management decisions and consequently reduce yield losses in corn.
Approach:
The project goals are conducted in two objectives: 1) Establish the association between inoculum intensity, production factors, disease development and weather in experimental plot trials; and 2) Disseminate corn disease information and management techniques through various outputs. In order to achieve objective 1, the work will focus on the following diseases: northern corn leaf blight (NCLB), gray leaf spot (GLS), southern rust (SR), Tar spot (TS), and Gibberella ear rot (GER). Experimental plot trials will be established in corn fields at three locations in Iowa to investigate associations among the disease intensity and the following factors: (1) planting date, (2) fungicide application at VT/R1, and (3) airborne inoculum density. For planting date, half of the field will be planted at the recommended planting date for the location (mid-late April) while the other half of the field will be planted four weeks later (mid-late May). A foliar fungicide will be applied to half the plots, while no fungicide will be applied to the other half of the plots. 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. For mycotoxin assessment, grain samples will be collected at harvest and shipped to a cooperator for mycotoxin contamination analysis. In order to achieve objective 2, 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.
