Biochemist Daniel R. Gallie and his research team, Todd Young and Jane Giesler-Lee, published their findings this week in the June issue of The Plant Journal.
Flowers in the corn ear develop in pairs but one from each pair aborts before pollination can occur. Because of the role that the plant hormone, cytokinin, plays in preventing organ death, the authors reasoned that cytokinin might rescue those flowers, which were destined to abort. The research team introduced a gene that enabled production of cytokinin in developing flowers.
"Surprisingly, not only did we observe rescue of flower abortion but the kernels produced from pairs of flowers fused into a single normal-sized kernel that contained two embryos and a smaller endosperm," said Gallie. "Because it is the embryo that contains the majority of protein and oil, the presence of two embryos doubles their content in corn grain. The reduction in the size of the endosperm in the kernel, the tissue that contains most of the carbohydrate, means that the nutritional value of the grain has been improved considerably."
The U.S. Department of Agriculture, National Science Foundation, and California Agricultural Experiment Station funded the seven years of research in this area.
Cereal grains are the most important crops to humanity, used for animal feed, for production of oil, protein, and starch, and for feeding the majority of the world's population. In a field in which increases in oil, protein, or starch content as small as 1 percent are considered a significant achievement, the ability to double their amount is a considerable advancement.
"Our findings are important to the field of flower development in corn in that they suggest that
Contact: Ricardo Duran
University of California - Riverside