Symptoms and Signs on Ribes

Rusts

White Pine Blister Rust - Symptoms and Signs on Ribes

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Ribes leaves infected with Cronartium ribicola. Uredinia are yellow spots on the leaves.

uredinia on Ribes

Uredinia (yellowish areas) produce urediniospores.

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Another view of the uredinia produced on the lower surface of infected leaves.

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Microscopic view of urediniospores. Note spiny appearance.

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Teila forming on leaf. Some uredinia can also be seen in the center of the photo.

telia of blister rust

By late summer, susceptable Ribes can have lots of telia on the lower leaf surface.

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Telia viewed with a hand lens on leaf surface. Basidiospores will be produced from the teliospores.

basidiospores blister rust

A stereophoto showing the basidiospores forming. These spores reinfect pines. With stereo-classes you could see this in 3D.