Mildew (form of fungus)
Mildew is a type of mold that primarily affects plants and damp organic materials, characterized by its two main varieties: downy mildew and powdery mildew. Downy mildew manifests as faded yellow or green splotches on the upper surfaces of leaves, accompanied by cottony patches on the undersides, commonly thriving in cool, moist conditions. In contrast, powdery mildew starts with a general discoloration before developing a white fuzz that can cover a significant portion of the plant. Both forms of mildew require moisture to grow and can cause weakening of plants, which is particularly concerning for agricultural crops as it may affect the quality of fruits and vegetables. Specific plants, such as cucumbers, roses, and lilacs, are especially vulnerable to powdery mildew, while downy mildew can proliferate under inadequate spacing and poor air circulation. Effective management strategies include maintaining proper plant spacing, ensuring cleanliness around infected plants, and utilizing antifungal treatments when necessary. Understanding mildew is crucial for both home gardeners and commercial growers to protect plant health and productivity.
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Mildew (form of fungus)
Mildew is a type of mold commonly found on certain plants. It comes in two varieties: downy mildew and powdery mildew. Downey mildew presents as faded yellow and green splotches on the tops of leaves with cottony patches of fungus on the undersides. Powdery mildew first presents as a general discoloration and then becomes a white fuzz that can spread over much of a plant. Both can be controlled with standard antifungal practices.
Overview
Mildew is a specific type of mold found primarily on plants and damp organic matter. Mold is made up of fungal particles with identical nuclei. These single-celled particles are called yeasts. Together, yeasts form multicellular structures called hyphae.
All mold requires moisture to grow. When indoors, this moisture can come from any number of sources: washing, humidifiers, condensation, or leaks. Once mold begins to grow in a home, it looks like brown or green stains spreading across a surface. Certain types of mold break down the surface upon which they grow, making them problematic when they grow on manmade structures.
While other types of mold can grow on most organic materials, mildew primarily grows on living plants, food, and actively damp surfaces. The two most common types of mildew are downy and powdery.
Powdery mildew is a common plant disease. Certain plants, such as crab apples, roses, cucumbers, lilacs, and plants from the genus Monarda, are extremely susceptible to powdery mildew, though almost any other type of living plant can develop powdery mildew. Crowding, a lack of air circulation, and high humidity all make plants more susceptible to powdery mildew. However, all species of powdery mildew are specific to the plants on which they grow. A species of powdery mildew that infects roses cannot infect other types of plants.
Powdery mildew may weaken or discolor plants as it starts to take hold. Once an infestation is established, white fuzz or splotches will appear all over the plant. The white fuzz is the mildew. While not lethal to the plant, powdery mildew will weaken it. This is important for farmed plants, as it will alter the flavor of any fruits or vegetables the plant produces.
When downy mildew infects a plant, the plant will begin to show faded yellow or white splotches on its leaves. Downy mildew often occurs in cool, moist, climates. The faded patches on the tops of the leaves will correspond to white or gray cotton-like fungal patches on the undersides of leaves.
To prevent downy mildew in domesticated plants, growers should make sure the plants are properly spaced apart. Additionally, they should keep the ground under infected plants clean to prevent the fungus from using other avenues of spreading. If any plant in a population develops a particularly severe infection, that plant should be removed. If an infection is still mild, plant growers can use an antifungal spray to combat it.
Bibliography
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