Cucumber Cladosporium is a most commonly a saprophyte, living off of decaying plant tissue. It also can be a pathogen causing numerous scab diseases, as well as leaf spots and blights. Cladosporium attacks developing leaves, shoots, nuts and fruits.
Mature tissues seem to be resistant to infection.
Symptoms of scab diseases on pecan nuts and peach fruit are similar. Small, round, sometimes sunken, olive-black to black spots appear on developing fruits and nuts. Spots may grow together so that the entire surface of pecan nuts turn black. On peach, the spots are usually on the upper side of the fruit which may crack following infection. Cladosporium produces spores mostly on the underside of leaves.