Control of sexuality in Asplanchna brightwelli: threshold levels of dietary tocopherol and modification of tocopherol response by exogenous and endogenous factors
Ingestion of one prey rotifer containing about 0.02 pg tocopherol was sufficient to cause young amictic females to produce a high proportion of mictic daughters. Varying the concentration of emulsified tocopherol and the population density of amictic females suggested that mictic-female induction approached an all-or-nothing response at relatively high population densities and increased with population density only when population densities were very low. Amictic females hatching from resting eggs were less likely to produce mictic daughters than those hatching from parthenogenetic eggs.
Keywordsrotifers Asplanchna population dynamics resting egg sexuality tocopherol
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