First Report of Phytophthora occultans Causing Dieback of Buxus sempervirens in the Czech Republic.

In Nov 2011, and then recurrently since Sep 2020, an extensive decline has been recorded in boxwood (Buxus sempervirens), sometimes with several dozens of damaged individuals planted in private gardens and public areas and purchased in amateur markets in the Czech Republic. The leaves of the plants first showed orange-bronze discoloration, then dried and fell off, and the affected plants died. The roots, collars and stems of these plants had dark brown to black necrotic lesions.

MALDI-TOF MS as a method for rapid identification of de Bary, 1876.

The number of described species of the oomycete genus is growing rapidly, highlighting the need for low-cost, rapid tools for species identification. Here, a collection of 24 species (42 samples) from natural as well as anthropogenic habitats were genetically identified using the internal transcribed spacer (ITS) and cytochrome c oxidase subunit I (COI) regions. Because genetic identification is time consuming, we have created a complementary method based on by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS).