Monilinia vaccinii-corymbosi

Monilinia vaccinii-corymbosi was described by J.M. Reade in 1908 as Sclerotinia vaccinii-corymbosi. In 1936, Edwin Earle Honey transferred it to the genus Monilinia. == Description ==

In the spring, Monilinia vaccinii-corymbosi infects the young shoots and leaves of blueberry plants, causing them to die. The fungus produces a layer of gray spores on the plant. The apothecia of M. vaccinii-corymbosi are brown in color and about 1-3.5 centimeters tall. The stipe is about 1-2 millimeters wide. The cap is cup-shaped and about 5-10 millimeters wide. They grow out of mummified fruit. == Life cycle ==

Primary infection Apothecia of Monilinia vaccinii-corymbosi sprout from mummified blueberries in early spring, releasing sexually-produced ascospores into the air. These ascospores land on young shoots, Eventually, the skin of the blueberry falls off, causing the pseudosclerotium to resemble a small black pumpkin. The pseudosclerotium overwinters on the ground. In early spring, apothecia sprout and release spores, continuing the life cycle. == Economic significance ==

Monilinia vaccinii-corymbosi is considered a serious pest to blueberry farms. In 1969 in British Columbia, M. vaccinii-corymbosi caused $66,462 in damage to highbush blueberries. In New Hampshire, infection rates reached 85%, with organic farms having nearly 100% loss rates, as of 2021. == Management and control ==

Several methods are used for controlling Monilinia vaccinii-corymbosi. Mulching is done to cover up pseudosclerotia and has been shown to prevent apothecia from growing. Fungicides are also used to control the fungus. Additionally, certain blueberry varieties have demonstrated resistance to the disease, such as Legacy, Powderblue, and Duke. == References ==