Phytophthora Found on Petunias
Posted: June 12, 2012
Given that late blight (Phytophthora infestans) has been confirmed on tomatoes and potatoes in Pennsylvania this year, it is possible that the petunia was infected with Phytophthora infestans.
The bottom line is that greenhouse operators, especially those growing both tomatoes and petunias, should be aware that the weather conditions of late (wet...frequently) are ideal for Phytophthora outbreaks. Spores may be blowing into greenhouses from outdoors. They MUST be examining their plants carefully and frequently. Look for collapsing, gray to browning foliage. Plants may look as though they are melting away. Get a positive diagnosis as quickly as possible. Contact your PDA inspector or local extension office for advice.
- Professor of Plant Pathology