Anthracnose on Pumpkins

Problem of the Week

Anthracnose on Pumpkins

This Week, August 13:
As reported in last week's 'VegNet, The Newsletter', Vol. 3, No. 18, Anthracnose is developing rapidly on pumpkins in central and southern Ohio. Humid weather with high temperature favor development of this fungal disease. Spores are spread mainly by splashing water, so frequent rains will increse disease severity.

II. Copper Phytotoxicity and Aphids on Pumpkins

Anthracnose on Pumpkin Leaves

On leaves, lesions first appear near veins and are roughly circular, range from light brown to reddish, and can reach more than 1 cm in diameter. First lesions are mainly visible on the upper surface.

Anthracnose lesions begin as orange or pink spots on leaf veins. (Leaf underside; See yellow arrows.)

The leaves may be distorted and the centers of the lesions may crack or drop out creatng a shot hole appearance.

When main veins are destryoed, large portions on the leaves begin to scorch. On petioles and stems, shallow elongated tan spots develop which result in girdled areas

Fruit Effects

Infected fruit develop sunken, watersoaked areas. These areas expand and develop tiny black specks in the center. Under humid conditions, pink or orange sticky spores ooze from the black specks.

	On leaves, lesions first appear near veins and are roughly circular, range from light brown to reddish, and can reach more than 1 cm in diameter. First lesions are mainly visible on the upper surface.
	Anthracnose lesions begin as orange or pink spots on leaf veins. (Leaf underside; See yellow arrows.)
	The leaves may be distorted and the centers of the lesions may crack or drop out creatng a shot hole appearance.
	When main veins are destryoed, large portions on the leaves begin to scorch. On petioles and stems, shallow elongated tan spots develop which result in girdled areas