Norin-10-based semidwarfism.
Many short-strawed wheats, including the Norin-10-based semidwarfs now grown in many countries, are characterized by their relative "insensitivity" to gibberellic acid. The nature of this insensitivity, its genetic control, and the relationships between the Gai genes and the Rht genes, which control height reductiion in Norin-10 and Tom Thumb wheats, are described. The role and potential of these genes in agriculture and their relationship to other genes affecting yield, height, and other agronomic features are considered.