ABSTRACT
The imidazolinones are a class of herbicides that control a broad spectrum of weeds at low rates and are used throughout the world in legumes, cereals, forests, and plantation crops. This chapter reviews the history, selection, and development of imidazolinone-resistant crops and their role in efficient and cost-effective weed management. Although the imidazolinone herbicides control many of weeds that are a problem in corn, the use of these herbicides on corn is not recommended because of damage to crop. In addition to using cell-culture selection, a pollen-mutagenesis procedure was used to obtain imidazolinone-resistant corn. This work was accomplished by ICI Seeds and resulted in the first commercially available herbicide-resistant crop seed. To increase the tolerance of wheat to imidazolinone herbicides, a project was initiated to obtain imidazolinone resistant wheat from a mutagenized seed population. Mutagenesis and selection was a four-step procedure which included seed mutagenesis, a seed soak in herbicide, preemergence herbicide application, and screening and selection of herbicide-resistant mutants.
