(1) Abteilung Trautner, Max-Planck-Institut für Molekulare Genetik, Ihnestrasse 63-73, D-1000 Berlin-West 33, Germany;(2) Present address: Department of Physics, Syracuse University, 13210 Syracuse, NY, USA
Abstract:
Phototropic reversal of Phycomyces sporangiophores can be elicited by a change to darkness during steady-state phototropism. The reversal lasts 25–30 min under these conditions. Control experiments show that the reversal is not caused by gravitropism. Tropic reversal is also elicited by the removal of a barrier during an avoidance response, showing that the reversal occurs at the output of the sensory transduction chain.