Where’s DON? What We Know About Deoxynivalenol Accumulation in Corn
2022
- Department of Plant Pathology, UW Madison
Project Media
Corn for silage is an important component of a dairy cow’s diet. This staple can be responsible for more than 50% of the total dry-matter intake for the cow, especially in the winter. To produce high-quality silage the use of brown mid-rib hybrids (BMR) has become common. These hybrids have lower indigestible lignin and can produce a higher-quality feed than their counterparts. However, with low lignin comes the tradeoff in low disease resistance. Gibberella ear rot and stalk rot have become diseases of concern in silage corn production in the northern corn production belt of the United States. Gibberella diseases not only damage the plant and can reduce yield and quality but can also lead to the accumulation of the mycotoxin deoxynivalenol (DON). To manage these diseases and reduce DON on susceptible corn hybrids, farmers are becoming increasingly reliant on foliar fungicide applications. Research has indicated that foliar fungicide applications can lead to mixed success in managing Gibberella ear rot and stalk rot. Research has also demonstrated that DON can accumulate in the stalk and ear portions of the plant independently. Weather from one year to the next may play a role in the type of disease (ear rot or stalk rot) and where DON accumulates. The location of infection by the Gibberella fungus and accumulation of DON likely influences the success in using fungicide to reduce DON levels in finished feed. This presentation will discuss what we know about DON accumulation in corn plant parts. We will also discuss current knowledge on managing DON accumulation using fungicide. Other aspects of Gibberella infection and effects on silage feed will also be discussed.