Intraspecific Variation in Growth and Morphology of the Bloom-Forming Cyanobacterium <i>Microcystis aeruginosa</i>

ABSTRACT In the laboratory, we documented large variation in the morphology, toxicity, and maximum population growth rates for 32 Microcystis aeruginosa strains isolated from 12 lakes. Growth rates and mean colony sizes varied significantly across strains and were positively correlated. However, growth rates were unrelated to toxin production.