Wet Weather Could Slow Planting, Increase Risk of Disease

Young corn plants ( Sonja Begemann )

Help your crop get off to the best start possible by managing for risk early. Because more wet conditions are likely, understand how that interacts with risk of diseases and what specific diseases are more likely this year.

Wet weather increases the risk of many early-season pathogens, and farmers in much of the U.S. are in store for yet another wet spring. Farmers in the Midwest can expect normal to below normal precipitation in the months before planting, while southeast and mid-south will see above normal precipitation.

“If we get a lot of storms, a lot of spring wetness or snow melt, that could lead to catastrophic flooding on the order of what we experienced last year in Nebraska and western Iowa,” says Brad Rippey, USDA meteorologist. “Early indications from the National Weather Service are that we will see a wet spring in most, if not all of these basins.”

Overall, colder weather is likely here to stay, too. Colder soils, like wet soils, can increase the risk of disease in young corn and soybean plants.

Here are a few diseases that prefer wet weather and ones to watch:

  • Pythium: ranges from seed rot or preemergence damping-off to early postemergence damping-off. Infected tissue becomes soft and brown as it rots. More likely in 50 to 55-degree, wet soils.

  • Phytophthora: can cause seed rot, preemergence damping off and early postemergence damping-off. Soft, brown tissue in impacted area, however, within several days it may dry out and shrivel up. Seedling blight makes established seedlings turn yellow, wilt and die. Most likely in heavy, wet soils, compacted or low areas, but can happen anywhere with excess rain.

  • Fusarium: more adaptable, can infect crops under a variety of temperature and moisture conditions. Plants stressed from weather extremes, including temperature and moisture, herbicide or physically damaged plants especially susceptible.

In most cases, the pathogen exists in the soil so review notes from previous growing seasons to know what fields are most susceptible to disease. In addition, there are many seed treatments on the market that defend against seedling diseases. If you have questions about it talk to your seed dealer. There might be some in-furrow options for areas with high pressure, too.

Read more about 2020 planting here:

Get Off to the Right Start with Starter Fertilizer

Soil Conservation Is A Marathon

Current U.S. Root Zone Moisture Map Wetter Than Last Year