Stage-III of rust fungi is marked by

Stage-III of rust fungi is marked by Teliospores.
Teliospores have been defined as the basidia-producing spores of rust fungi. The teliospores are important for the overwintering of most cereal rosts, and they are largely responsible for the formation of new physiologies races of the rosts.
Rusts are plant diseases caused by pathogenic fungi of the order Pucciniales.