The closest wild relative of maize, teosinte, does not look very promising as food. The ear is tiny compared to the domesticated one, and the grains are surrounded by hard fruitcases that are difficult to break open. Teosinte originated in Mexico, and, around 10,000 years ago, mutations in the wild population produced plants that attracted the attention of hunter gatherers looking for some starch in their diets. Saved seed was planted and desirable plants selected again in the next generation. Along with desirable traits, these early agriculturalists were selecting genes important for transforming a wild grass into a food plant. These same genes are being studied today to understand how maize and other crops in the grass family like rice, wheat, and sorghum produce grain. This knowledge is being used to create new varieties with better and consistent yield.
Dr. Erik Vollbrecht and his colleagues, Xiang Yang, Brandi Sigmon, Erica Unger-Wallace, and Zhuying Li, have studied mutations of some of the genes related to ear formation, among them, RAMOSA 1-3, which helped to transform the tiny teosinte ear with only 5-12 kernels into the large, massive corn cob we eat today. Dr. Vollbrecht, of the Department of Genetics, Development, and Cell Biology at Iowa State University, will be presenting this work at a symposium on Maize Biology at the annual meeting of the American Society of Plant Biologists in Mrida, Mexico (June 28, 10:40 AM).
The familiar spikes of grasses are the flower-bearing stems, or inflorescences, which produce tiny, wind-pollinated flowers. Different grass species, and especially the grain crops, differ in the number, length, and types of inflorescence branches, ranging from the straight spikes of wheat and barley to maize and sorghum with branched tassels. Maize has two separate inflorescencesthe male tassel or pollen-producing flowers, and the female flowers that produce the kernel-bearing ears. The terminal male i
|Contact: Erik Vollbrecht|
American Society of Plant Biologists