Rusts are plant diseases caused by

Rusts are plant diseases caused by pathogenic fungi of the order Pucciniales (previously also known as Uredinales).

Unlike other plant pathogens, rust usually affects healthy and vigorously growing plants, so the infection is limited to plant parts, such as leaves, petioles, tender shoots, stem, fruits, etc.[1] Perennial systemic infection may cause deformities such as growth retardation, witches brooms, stem canker, hypertrophy of the affected tissues or formation of galls.

Plants with severe rust infection may appear stunted, chlorotic (yellowed),