Tar spot, a fungal disease that can cause severe yield loss on susceptible hybrids, continued to spread quickly across the Corn Belt in 2019.
Stalk rot diseases occur in nearly all corn crops, leading to approximately 5% yield loss per year. Stalk rots can be more commonly found in high-yielding hybrids that produce large and heavy ears.
Prior to 2019 planting, AgVenture published an update on the advancement of tar spot across the Midwest. As of last week, AgVenture Corn Product Manager Darren Bakken has seen the disease move as far west as Boone County, Iowa.
Tar spot is a fungal leaf disease that infects corn leaves and causes lodging and yield losses. First confirmed in 2015, it has rapidly spread in persistence and reach. Yield losses from tar spot infection can be severe.
Erwinia chrysanthemi pv. zeae is one of the most common causal agent of bacterial stalk rot. It is readily capable of establishing and thriving on corn and sorghum plants as it enters natural openings or wounds made from weather or pests.
One ear rot taking hold in many fields is Diplodia ear rot. It tends to thrive when there is wet weather and mild during grain fill. Upright ears with tight husks may promote Diplodia development in certain conditions.