Climatic conditions determine the extent of the disease.
Infected wheat can, however, be sent to approved facilities where it is steam rolled, a form of heat treatment, and sold as animal feed. The disease was first reported in 1931 in wheat-growing areas near the city of Karnal in the Indian State of Haryana. Since then, it has been found in all major wheat-growing States of India, as well as in Pakistan, Iraq, and Afghanistan. The disease may have been present in Mexico since 1970 and has been well established in some areas in northwestern Mexico since 1982. These commodities can enter only with a USDA permit for scientific purposes.