Karnal bunt

Karnal bunt is a fungal disease of wheat, rye, and triticale. The fungus Tilletia indica invades the kernels and obtains its nutrition from the endosperm, leaving behind waste products with a disagreeable odor that makes bunted kernels too unpalatable for use in flour. Karnal bunt was named after Karnal, the district in the Indian state of Haryana where it was first reported in the 1930s. Fifty years later it had become pervasive in Mexico, and it was first discovered in the United States in 1996. Quarantines, some of them controversial, were imposed there. A few of them have since been lifted, but the USDA continues to monitor the disease in the United States.

Reference

 * APHIS. Pest Detection and Management Programs - Karnal Bunt