Abstract
A description is provided for Podosphaera myrtillina. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. DISEASE: Powdery mildew of plants belonging to the Vacciniaceae only. Infected plants usualy change colour, Ascomata form a brown layer on damaged green parts of host. Development of the disease can by epiphytotic, in which case the crop of berries can be significantly reduced. HOSTS: Arctostaphylos alpina (?), Ledum groenlandicum (?), Vaccinium angustifolium (V. pennsylvanicum), V. × intermedium (V. myrtillus × vitis-idaea), V. membranaceum, V. myrtillus, V. oxycoccos (Oxycoccus palustris, O. quadripetalus), V. uliginosum, V. vitis-idaea. [Type species - Vaccinium myrtillus] GEOGRAPHICAL DISTRIBUTION: Asia (temperate areas only): Republic of Georgia, Russia (all Russian far east including Kamchatka; west, south and east Siberia including Yakutia). Europe: Austria, Belgium, Bulgaria, Czech Republic, Denmark, Estonia, Finland, France, Germany, Great Britain, Greenland, Hungary, Iceland, Italy, Latvia, Lithuania, Netherlands, Norway, Poland, Rumania, Russia (western and northwestern areas of European part, Moscow oblast'), Slovakia, Sweden, Switzerland, Ukraine, former Yugoslavia. North America: Canada, USA (including Alaska). TRANSMISSION: Probably by wind-dispersed conidia. The rôle of ascospores in disease transmission is unknown, although it has been supposed that they can cause the initial stage of the disease. Infection can also, however, occur from colonies surviving in host buds. In addition, ascomata of Podosphaera myrtillina, especially of var. major, intertwine their appendages to form clusters which are dispersed by rain or wind.
Revision of rock fossils of Dryinidae and Embolemidae (Hymenoptera: Chrysidoidea)