The family Pucciniaceae, belonging to the order Pucciniales, is a large group of fungi commonly known as rust fungi. Members of this family are obligate plant pathogens, meaning they must infect living plants to complete their life cycle. Pucciniaceae species are characterized by complex life cycles that often involve multiple spore stages and sometimes alternate between two different host plants. They cause rust diseases on a wide variety of crops, grasses, and trees, leading to significant agricultural and ecological impacts. These fungi are easily recognized by the reddish, orange, or brown pustules they produce on infected plant tissues, which contain spores that facilitate further spread of the disease.