Uptake and polar transport of indoleacetic acid in moss rhizoids

Rhizoids of the moss Funaria liygrometrica Sibth. (L.) accumulate auxin in a manner similar to whole protonctnata. In the base of rhizoids auxin accumulation is always higher than in the tip. Auxin is transported in rhizoids from the tip to the base. The auxin transport is strictly polar. This can be explained by the different pattern of auxin accumulation in tip and base of rhizoids which represents a good model for the chemiosmotic hypothesis of polar auxin transport. The involvement of such a polar transport in moss development is discussed.