Fungi --> Basidiomycota --> Pucciniomycetes

Hemileia vastatrix, Coffee Rust

Life Cycle

Direct, single host: Coffee Species (Coffea arabica, Coffea canephora, and more)

Half-smooth, kidney shaped urediniospores infect coffee plant leaves through the open stoma. It inhabits intercellular space where it extends mycelium (the network of white filaments known as hyphae) between cells and grows haustorium projections into cells to absorb nutrients. 10-14 days post-infection, uredinia produce more infectious urediniospores.

Host Information

Infected leaves drop prematurely during the dry season, which harms trees but also prevents spread to some extent. Once the wet season begins again, new leaf growth allows for the continued spread of this pathogen. Since H. vastatrix is infectious to important cash crops, human interference has at times helped the parasite's spread (urediniospores were introduced to Brazil in the 1970s, and coffee breeding has resulted in low genetic diversity among highly susceptible coffee plant populations) and at other times hindered it (fungicides, planting methods and spacing to prevent spread, selective breeding of coffee plants for resistance).

Distribution

H. vastatrix is widespread everywhere coffee is grown--the Americas, Africa, Asia, Oceania, etc.

https://www.apsnet.org/edcenter/disandpath/fungalbasidio/pdlessons/Pages/CoffeeRust.aspx