Aggressiveness of Loose Kernel Smut Isolate from Johnson Grass on Sorghum Line BTx643

An isolate of loose kernel smut obtained from Johnson grass was inoculated unto six BTx643 sorghum plants in the greenhouse to determine its aggressiveness. All the BTx643 sorghum plants inoculated with the Johnson grass isolate were infected. Mean size of the teliospores from the Johnson grass, infected BTx643, and naturally infected sorghum was similar, measuring 0.79, 0.75, and 0.82 µm, respectively. This short communication shows that loose smut on Johnson grass if not controlled around production areas could pose a serious threat to sorghum production.