Forest path exam 1

A Ribes leaf with discrete orange pustules. What would you ask, or look for first? Given
that you found fungal spores in the pustules, what next? If this is a rust, are the pustules
Aecia, Uredia, or Telia? If telia, what then. Once you find out that this is a heteroecious
macrocyclic rust, then what? What do you need to know for control?

Autoecious

use only one host during their life cycle

Heteroecious

alternate between two often totally unrelated hosts

macrocyclic

produce all of the 5 spore stages

microcyclic

produce only 2 or 3 spore stages

Rust life history

P-A-U-T-B

Pycnium

Pycniospores (haploid n)

Aecium

Aeciospores (dikaryotic n + n)

Uredinium

Urediniospores (dikaryotic n + n)

Telium

Teliospores (diploid n2)

Basidium

Basidiospores (haploid n)