Common Diseases of Tomato and Their Control: Late Blight
Karen Meyers The fungus-like water mold, Phytophthora infestans, causes late blight in tomatoes and potatoes as well as in some other members of the nightshade family, Solonaceae. It appears first as dark…
Common diseases of Corn and Their Control: Goss’s Wilt
Similar to Stewart’s wilt, this bacterial disease has two phases. The first appears early in the season and is characterized by orange to brown discoloration of diseased vascular tissues and…
Common Diseases of Corn and Their Control: Smut
Caused by the fungus Ustilago maydis, this disease can affect all above ground parts of the plant but is most economically significant when it attacks the ears. It causes the…
Common Diseases of Corn and Their Control: Northern Corn Leaf Blight
Northern corn leaf blight is caused by the fungus Exserohilum turcicum, and first appears on the lower blades at the time of silking or at full maturity It is characterized…
Common Diseases of Corn and their Control: Stewart’s Wilt
Caused by the bacterium, Pantoea stewartii, Stewart’s wilt has two phases. The first affects seedlings that may develop linear pale green to yellow streaks, wilt and dry up. The second…
Common Diseases of Cucumber and Their Control: Angular Leaf Spot ( Pseudomonas syringae pv. lachrymans)
Karen Angular leaf spot is a bacterial disease affecting cucumber and other cucurbits, including squash, pumpkin, and melon. The infection begins with small, angular, brown to straw-colored water soaked spots on…
Common Diseases of Corn and Their Control: Rust
The most common corn rust is caused by the fungus Puccinia sorghi and usually appears after tasseling as dark, reddish-brown pustules on the upper and lower surfaces of the leaves.…
Common Diseases of Corn and Their Control: Gray Leaf Spot
Gray leaf spot is one of two common foliar fungal diseases of corn. It is caused by either Cercospora zeae-maydis or Cercospora zeina and appears as grey rectangular, brown to…
Common Diseases of Cucumber and Their Control: Bacterial Wilt
Caused by the bacterium, Erwinia tracheiphila, bacterial wilt affects cucumber and cantaloupe severely, squash and pumpkin less so, and watermelon rarely. The first symptom is the wilting of leaves during…
Common Diseases of Tomato and Their Control: Early Blight
Early blight of tomato is a fungus disease usually caused by Alternaria solani or the more virulent A. tomatophila, and can also effect potatoes, peppers and other members of the…