Since Darwin first observed that plants bent towards light, Phototropism has been one of the most studied response of plants. However much of the events governing this response have remained shrouded in mystery. It was until very recently that the mechanisms involved have been elucidated. One of the major contributing factors in helping to unravel and explain this phenomenon has been the isolation and subsequent study of mutants defective in their response to light. In our lab we have successfully isolated a few mutants which completely lack or are impaired in their response to red or blue light. We are now attempting to explain the regulatory functions of these loci and determine their role in the signal transduction pathways of such light-mediated responses.
A non phototropic seedling of tomato
Phototropic response of 3 days old tomato seedlings to unilateral blue light( Blue arrows indicate direction of light).