Pierce’s disease (PD) is a bacterial disease of grapes named for Newton Pierce, who described the disease in 1892. The bacterium species is Xylella fastidiosa.
Tag Archives: Fruit
Brix: How Do We Measure It?
Now we have a definition of brix: the weight of dissolved sugar expressed as a percentage of the weight of the entire solution. The next question is how we measure brix.
Phytophthora Blight
Phytophthora blight, also known as late blight, is a fungal disease caused by several species of the genus Phytophthora. Affected plants include: Cucumbers. Squash. Pumpkins. Cantaloupe. Watermelons. Tomatoes. Eggplants. Peppers. Potatoes. Beans. The fungi involved flourish in wet, moderately warm weather. They spend the winter in infected tubers and plant matter. The disease is spreadContinue reading “Phytophthora Blight”
Brix: What is It?
Brix is one of those topics that come up fairly frequently in sustainable agriculture. Simply put, brix is a measure of the sugar content of a plant or other substance. To be more specific, Brix expresses the weight of dissolved sugar as a percentage of the weight of the entire solution. Pure water has aContinue reading “Brix: What is It?”
Peach Leaf Curl
Peach leaf curl is a common disease caused by the fungus Taphrina deformans. Besides peaches, susceptible plants include nectarines and almonds. The peach leaf curl fungus spends the winter in the bark and buds of its hosts. It enters new buds as they begin to swell and open in the spring, spread by rain andContinue reading “Peach Leaf Curl”
Growth Cracks
Growth cracks are a problem most gardeners will have to contend with sooner or later. Fortunately, the problem is structural in nature, and therefore will not cause an epidemic. Commonly affected plants include: Tomatoes (especially beefsteak varieties). Eggplants. Cucumbers. Melons. Grapes. Jalapeño peppers frequently crack, as well, but this is normal and not likely toContinue reading “Growth Cracks”
Fusarium Wilt
Fusarium wilt is a disease common to the southeastern United States. It is caused by the fungus Fusarium oxysporum and affects numerous garden plants, including vegetables, small fruits, and flowers. The most susceptible host species include: Tomatoes. Sweet potatoes. Cucumbers. Watermelons. The disease is spread through infected soil. Once it is introduced, it is nearlyContinue reading “Fusarium Wilt”
Fire Blight
Fire blight, found across North America, is a disease to be reckoned with. Caused by the bacterium Erwinia amylovora, this blight affects:
Downy Mildew
Downy mildew is caused by parasitic fungi of the family Peronosporaceae, a group of water molds. The resulting disease is quite common in humid climates, affecting most of the fruits, vegetables, flowers, and grasses that gardeners like to grow.
Cedar-Apple Rust
Cedar-apple rust is a disease caused by fungi of the genus Gymnosporangium. It affects the following common orchard and ornamental trees, as well as the invasive eastern red cedar: Apple. Crab apple. Pear. Hawthorn. Juniper. Due to its complicated life cycle, this disease is dependent on both deciduous and coniferous trees to survive: Galls onContinue reading “Cedar-Apple Rust”
