1. UC IPM
The aecial stage of pear rust, <i>Gymnosporangium libocedri.</i> The underside of a pear leaf with two groups of cup-shaped, fungal aeciospore-forming bodies that appear as pustules.
The aecial stage of pear rust, Gymnosporangium libocedri. The underside of a pear leaf with two groups of cup-shaped, fungal aeciospore-forming bodies that appear as pustules.
Credit: Robert D. Raabe