Red streaks form on sides of kernels and extend over the crown. Streaked kernels are more common at ear tips, especially if the husks are loose and kernels exposed.
Kernel Red Streak is caused by a toxin secreted during feeding by the wheat curl mite Eriophyes tulipae, the vector of the wheat streak mosaic virus.
Severity of symptom expression varies among hybrids. Kernel red streak is most common on yellow dent and least common on white corn. The streaking develops in the pericarp but does not affect the feed or nutritional value of corn. The reddish discoloration may affect certain uses of food grade corn, and may thereby reduce premiums.
Ciampitti, I. 2014. Abnormal Corn Ears. Available at https://www.agronomy.k-state.edu/extension/documents/crop-production/Abnormal_Corn_Ears.pdf [URL verified 1/16/2019]. Kansas State University.