[Assimilation of nitrate in the dark by Lemna minor L].

1. Lemna minor is able to reduce nitrate in the dark when the nutrient medium contains yeast extract and glucose in addition to minerals salts. 2. When organic N is offered as a source of N in addition to nitrate, the former is assimilated preferentially, but both assimilation processes take place simultaneously. 3. Assimilation of nitrate in the dark under ecological conditions can be excluded.