Rust (fungus) Rust (fungus) Rusts are plant diseases caused by pathogenic fungi of the order Pucciniales (previously also known as Uredinales). An estimated 168 rust genera and approximately 7,000 species, more than half of which belong to the genus "Puccinia", are currently accepted. Rust fungi are highly specialized plant pathogens with several unique features. Taken as a group, rust fungi are diverse and affect many kinds of plants. However, each species has a very narrow range of hosts and cannot be transmitted to non-host plants. In addition, most rust fungi cannot be grown easily in pure culture. A single species of rust
Juvenile (organism) fully mature and their development and growth stops. Their juveniles are larvae or nymphs. In vertebrates and some invertebrates (e.g. spiders), larval forms (e.g. tadpoles) are usually considered a development stage of their own, and "juvenile" refers to a post-larval stage that is not fully grown and not sexually mature. In amniotes and most plants, the embryo represents the larval stage. Here, a "juvenile" is an individual in the time between hatching/birth/germination and reaching maturity. Juvenile (organism) A juvenile is an individual organism that has not yet reached its adult form, sexual maturity or size. Juveniles sometimes look very different