Which disease occurs in warm, humid conditions and is known for smoke ring patterns?

Pythium blight is indeed associated with warm, humid conditions, making it a prevalent issue in such environments. This disease is caused by the pathogen Pythium spp. and is notorious for its distinctive appearance on turfgrass, particularly characterized by the "smoke ring" patterns that occur around the edges of affected areas. These pattern formations happen as the pathogen creates lesions and wilts the grass, often resulting in patches that appear sunken or burnt with a distinct halo effect.

Understanding the specific environmental conditions that lead to Pythium blight is crucial for effective management and prevention strategies, as it thrives in excessive moisture and temperatures conducive to its development. The other diseases mentioned, while they may also appear in similar conditions, do not exhibit the characteristic smoke ring patterns seen with Pythium blight, making this option the most accurate response to the question.