Early Blight

A  disease which can affect the foliage, stems and fruit of tomatoes.

Symptoms: Dark spots with concentric rings develop on older leaves first. The surrounding leaf area may turn yellow. Affected leaves may die prematurely, exposing the fruits to sun scald.

Management: Early Blight fungus overwinters in plant residue and is soil-borne. It can also come in on transplants. Remove affected plants and thoroughly clean fall garden debris. Wet weather and stressed plants increase likelihood of attack. Copper and/or sulphur sprays can prevent further development of the fungus.

To know details: http://www.ext.colostate.edu/mg/gardennotes/718.html

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