Which management practice can help control corn smut?

Rotation with other crops is an effective management practice to control corn smut, which is caused by the fungus Ustilago maydis. Crop rotation helps break the lifecycle of the pathogen by preventing it from continuously finding its preferred host—corn. By alternating corn with other crops that are not susceptible to Ustilago maydis, the overall population of the pathogen in the soil can decrease over time, reducing the risk of infection in subsequent corn crops.

The other options, such as frequent flooding of fields, could create conditions conducive to other plant diseases and may not specifically target the control of corn smut. Applying high nitrogen fertilizers tends to promote lush corn growth but can inadvertently create a more favorable environment for the fungus, potentially increasing the incidence of corn smut. Planting monocultures, on the other hand, provides a steady host for the pathogen, allowing it to thrive more easily, thus leading to higher infection rates. Therefore, rotating crops effectively disrupts the life cycle of the pathogen, making it the appropriate choice for management of corn smut.