Abstract
A description is provided for Synchytrium macrosporum. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Karling (1964) lists the following hosts: Amaranthus berlandia, Ambrosia aptera, A. psilostachya, A. trifida, Ammi majus, Croton monanthogynus, Erigeron canadensis, Helenium tenuifolium, Iva ciliata, Modiola caroliniana, Nandina dornestica, Oenothera laciniata, Parthenium hysterophorus, Phyla incisa, Ratibida pinata, Riccinus communis, Rubus trivialis, Solanum elaegnifolium, Specularia perfoliata, Torilis japonica, Vicia faba, Vigna sinensis, Xanthium strumarium. However, experimentally infected hosts total over 1483 species in more than 933 genera of 185 families (57, 2425). DISEASE: Lavender-red galls develop on the leaves and stems of hosts. GEOGRAPHICAL DISTRIBUTION: North America (Texas). TRANSMISSION: No reports, but presumably by dissemination of resting spores, with local dispersal by zoospores swimming in water films.