The Relationship of Sprouting and Kernel Color

Dr. Gary Paulsen

Department of Agronomy, Kansas State University

White wheat was once thought to sprout rapidly because it lacked the red pigmentation that colored the grain and also inhibited the sprouting of red wheat varieties. This direct relationship between the absence of red pigmentation and susceptibility to sprouting suggested that there was no resistance to the sprouting problem in white wheat. However, researchers at Kansas State University found that the relationship between grain color and sprouting is more complex.

The researchers observed that the grain of both red wheat and white wheat contains compounds that inhibit sprouting. The difference is in the embryo or "germ" (the part of the kernel that germinates to form the new seedling). In most varieties of red wheat, the embryo is highly sensitive to the inhibitors and does not germinate quickly. In white wheat, the embryo is relatively insensitive to the inhibitors and sprouts when conditions are favorable. Geneticists call the relationship, in which the same genes control more than one trait, a pleiotropic effect. In the case of wheat, the genes that control grain color also affect sensitivity of the embryo to the compounds that inhibit sprouting.