Weather Enhances Crop Diseases
.png)
Some crop diseases are intensifying and being enhanced by current weather conditions. Cool night time temperatures (below 70°F), humid conditions, and wet leaves enhance tar spot in corn. Tar Spot is often helped by August and September weather conditions. Red Crown Rot in soybeans is also being found in Ohio. Corn tar spot ( Phyllachora maydis ) is becoming a major corn disease. Tar spot fungus came from Central America and is spreading by wind into corn growing states. Tar spot grows rapidly when temperatures are 60-70°F and humidity is 75% or higher with rainy, foggy, cloudy summer weather spreading this disease. Corn will mature early with reduced ear weight, poor kernel fill, stalk rot, and lodging with yield losses ranging from 0-60 bushel per acre, depending upon disease severity. Corn tar spot was spotted earlier this year at the OSU South Charleston research plots. Due to weather conditions at that time, it was at relatively low levels and mild. It was found ...