Culture and taxonomic status of Chlorochytrium lemnae a green algal endophyte

Pure (axenic) strains of an intercellular endophyte identified as Chlorochytrium lemnae Cohn (= Chlorosphaeropsis lemnae Moewus) were isolated from infected duckweed (Lemna spp.). Pure cultures of the host were also obtained. Both grew well in mineral media, requiring no organic growth factors. In suitably dilute media, the algae could be induced to infect dead leaves of several different Lemna clones. Since its cells divide vegetatively by the formation of common cross walls (“desmoschisis”), Chlorochytrium lemnae should be transferred from the Chlorococcales to the Chaetophorales. The taxonomic status of other algae identified as Chlorochytrium—some of them demonstrated to be stages in the life-cycle of filamentous algae—should be re-evaluated.