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Colletotrichum lindemuthianum is a fungus which causes anthracnose, or black spot disease, of the common bean plant (Phaseolus vulgaris).It is considered a hemibiotrophic pathogen because it spends part of its infection cycle as a biotroph, living off of the host but not harming it, and the other part as a necrotroph, killing and obtaining nutrients from the host tissues.
This disease affects strawberry plant foliage causing purple spots ⅛ to ¼ inches across on the upper side of the leaves. [3] At first, the whole spot is purple but as the disease matures the center of the leaf spots on older leaves become tan or gray, then almost white.
Microscopically, the flyspeck-like spots and sooty blemishes are fungal mycelium adhering to fruit. The fungi live as saprophytes on the wax layer surface of apples and do not invade the peel. The hyphae, fruiting bodies, and survival structures of these fungi become melanized over time. SBFS fungi also grow on the surfaces of stems, twigs ...
The black spots are circular with a perforated edge, and reach a diameter of 14 mm (1 ⁄ 2 inch). Badly affected plants, however, will not show the circular patterning, as they combine to cause a large, black mass. The common treatment of the disease is to remove the affected leaves and spray with antifungal solutions.
As the disease progresses, the mycelium often becomes dotted with minute black points (cleistothecia), which are the sexual fruiting bodies of the fungus. [3] The fungus does not kill the host plant as it requires the hosts' water and nutrients to grow. It settles on foliage and gradually slows the host growth process.
To dispose of citrus debris it should either be heated to a minimum of 180 °F for two hours, incinerated, buried in a landfill, or fed to livestock. Plant trash should be moved with caution if at all to avoid spreading the infectious ascospores. Any trees that are infected with citrus black spot should be removed from the grove and disposed of.
The pathogen causes black spot of fruit, but can also be seen attacking the plant at its crowns, roots and leaves. [3] After planting, stunting and yellowing as well as wilting may occur. [4] General symptoms of the disease in other plants can also be seen on flowers, petioles, and roots. [5] Stems are also a prominent place to see symptoms.
People can observe P. infestans produce dark green, then brown then black spots on the surface of potato leaves and stems, often near the tips or edges, where water or dew collects. [9] The sporangia and sporangiophores appear white on the lower surface of the foliage. As for tuber blight, the white mycelium often shows on the tubers' surface. [10]