Plant Diagnostics

Pythium rot (root, stem or crown-herbaceous) - Pythium species (H)

Damage

First symptoms are yellow, stunted or wilted plants. Pythium infects young tissue, often root tips, and causes a dark brown to black wet rot that softens and disintegrates tissue. This disease commonly attacks below the soil surface from root tips to primary roots and sometimes to the base of the plant, and is favored by wet, poorly drained conditions.

Cultural Controls

Use pathogen-free growing media, plants, water, and equipment. Provide good drainage. Scout regularly for plants that either wilt or collapse during periods of water stress. Avoid water stress (both too much and too little) and extreme temperatures.

Chemical Controls

Boscalid+Pyraclostrobin
Signal Word: Caution
Pesticide Class: Local Protectant
Cyazofamid
Signal Word: Caution
Pesticide Class: Protectant
Etridiazole
Signal Word: Warning
Pesticide Class: Protectant
Etridiazole+Thiophanate-methyl
Signal Word: Danger
Pesticide Class: Protectant, Systemic-upward only
Fenamidone
Signal Word: Warning
Pesticide Class: Protectant
Fludioxonil+Mefenoxam
Signal Word: Caution
Pesticide Class: Protectant, Systemic-upward only
Fosetyl-aluminum
Signal Word: Caution
Pesticide Class: Systemic
Mefenoxam
Signal Word: Warning
Pesticide Class: Systemic-upward only
Phosphorous acid
Signal Word: Caution
Pesticide Class: Systemic
Propamocarb-hydrochloride
Signal Word: Caution
Pesticide Class: Systemic-upward only
Pyraclostrobin
Signal Word: Caution
Pesticide Class: Local protectant

Locations Affected

leaves, roots, stem

Plant Environment

greenhouse, outdoors

Scouting Season:

January - Early , January - Mid , January - Late , February - Early , February - Mid , February - Late , March - Early , March - Mid , March - Late , April - Early , April - Mid , April - Late , May - Early , May - Mid , May - Late , June - Early , June - Mid , June - Late , July - Early , July - Mid , July - Late , August - Early , August - Mid , August - Late , September - Early , September - Mid , September - Late , October - Early , October - Mid , October - Late , November - Early , November - Mid , November - Late , December - Early , December - Mid , December - Late

Plants Affected


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