What is "leaf spot"

alt. (context botany English) Any of various fungal or bacterial diseases of plants that cause blemishes on their leaves. n. (context botany English) Any of various fungal or bacterial diseases of plants that cause blemishes on their leaves.

Leaf spots are round blemishes found on the leaves of many species of plants, mostly caused by parasitic fungi or bacteria.

A typical spot is "zonal", meaning it has a definite edge and often has a darker border. When lots of spots are present, they can grow together and become a blight or a blotch. Fungal spots are usually round or free-form in shape.

In most cases, leaf spots are considered to be only a cosmetic problem, but they can have economic effects on nurseries or in floriculture.