Monilinia fructicola (Wint.) Honey
and M. laxa (Aderh. & Ruhl.) Honey
Brown rot is a relatively unimportant disease of quinces. It is more common in eastern than in western growing areas. The disease usually attacks fruits while on the tree, but small, overlooked lesions can enlarge somewhat in transit or in stored fruits at temperatures above 32 °F. The rot is rarely initiated, however, at temperatures below 50 °F. The typically brown circular rot (see photo) is moderately firm or slightly spongy, often with puckered margins at the surface. Insect injuries and wounds are common sites of infection. Calyx and stem end decays also occur. As the lesion enlarges, the central or older portion becomes darker with age. The disease is rarely seen on the market (see Apples, Brown Rot).
Brown rot on quince