Is Black Knot Fungus Harmful To Humans?
The answer is amply no. We are looking for this answer with great emphasis that no Black knot fungus affects human beings. Black knot fungus assails Prunus trees. It is sometimes seen as a tumor-shaped sturdy, jagged, unkempt black galls. Tree branches and trunks are usually affected by the fungus. This plant disease is caused by a fungus Apiosporina morbosa (also recognized as Dibotryon morbosum and Plowrightia morbsum). The fungus affects plum trees as well as cherry trees.
It assails trees like peach, mayday, flowering almond, amur cherry, Japanese plum, and apricot too as these belong to the genus prunus. The knots may differ in the size ranging from 0.5 inches to 12 inches, 1-30 cm approximately. However, one tree may have many infected knots. Sometimes knots appear whitish or light pink due to the fungal parasite, Trichothecium roseum.
Recognition of Black knot fungus
Black knot fungus in its initial years will appear as a tiny, olive-green gall as conidia develop over the surface will harmful to humans. After 2-3 years of ripeness, the swelling grows bristly charcoal black. The gall will transit the infection by forsaking hundreds of sexual spores called ascospores during early spring.
The ascospores will mature into asci, each ascus contains eight ascospores. The spores are transmittable through heavy wind currents and rain. So, the infection usually spreads during spring when it rains on cats and dogs. Recent researchers have shown that two factors determine the growth of the fungus rainfall and temperature. Injured and sore or bruised tissue of the tree is more susceptible to the spread of Black knot fungus.
Concealment of Black knot fungus
During the winter season, pruning or trimming of the infected areas of the tree is effective and easier because during late fall or winter trees become naked. So, it will be easier to identify the actual area of infection by the fungus. Early spring can also be an optimum time to lop off the infected parts. Loping off the infected area 6-8 inches to decrease the risk of spreading again and does not prevail over and embezzle the tree.
After completion of the pruning, make sure the tools gets sterilized so that the infection does not reach another tree. Dereliction of any of these steps will not conceal the growth of the Black knot fungus. The pruned part infected with the fungus should be buried under the ground or burned as the knot can release spores for up to four months after cutting. Plants need to get the care and must be monitored to prevent any further infection by the fungus. Avoid planting trees in areas already affected with Black knot fungus or deserted orchards, where the trees are audited with the disease. For better plantation cut off the diseased or wild varieties of plants and trees which may harm the new young disease-free plant.
Treating of Black knot fungus
One of the effective ways to treat the infection created by the Black knot fungus is to use a fungicide. Using a limited quantity of insecticides and pesticides can be useful for the tree as it will prevent the growth of unwanted infections and diseases. For trees bearing fruits, organic treatments can be helpful. But using a huge amount of fungicide or pesticide can become harmful as it will damage the internal tissue of the plant. The frequency of using the fungicide should match the level and depth of the infection.
Unless it is an important fruit-bearing tree or commercial tree and the infection spreads very rapidly, using fungicide is relevant. Otherwise for trivial infections, pruning will be efficient. Some trees have genetic resistance to the Black knot fungus. Before planting the tree make sure that it is genetically resistant. It is one of the ways in which this fungus can be knocked down. To biologically control the growth of the Black knot fungus, the fungal parasite Trichothecium roseum can be used.
Black Knot’s origin
Black knot fungus was first found in Massachusetts in 1811. This plant disease is most common in America, especially in Northeast America. It is prevalent in Canada, Mexico, and the United States.
There are few incidences of the attack of the Black knot fungus is harmful to humans in Asiatic countries. Researchers have discovered that the young twigs and leaves die during the first stage of infection, trunks and heavy branches get slowly damaged by the Black knot fungus. Trees that have multiple knots may lose their attractiveness and productiveness. It will result in stunted growth of the tree if the Black knot attacks the young plant.
Conclusion
Planters often overlook the infection as it takes years for spreading of the infection. As the knot gets covered by the leaves it remains unidentified by the gardeners. In late fall or winter, when the tree becomes naked, planters identify the knot. So, before identification, the infection spreads. Commercial planters or gardeners quickly identify the disease because they inspect the trees regularly and incessantly. But all planters must acquire knowledge about plant diseases and infections irrespective of commercial and non-profit-making plants. Regular monitoring is necessary to prevent various diseases from infecting the trees and the plants.
