Responses of an annual plant to temporal changes in light environment: an interplay between plasticity and determination Academic Article uri icon


  • The development of the Mediterranean annual Onobrychis squarrosa L.(Papilionaceae) shows various responses to shade. The purpose here was to use this plant to consider the adaptive value of different responses and the signals by which they are elicited. A central hypothesis was that the developmental stage of the plant at which the signals are perceived is of major importance. Onobrychis plants growing in natural conditions were shaded by plastic covers that simulated the effects of neighboring plants. The shade was applied for various durations and at different times during the growing season. The plants were scored for the number of lateral branches, the relative dominance of the main or seminal shoot, the number and location of the leaves and the fruits, and the elongation of the stems. In autumn before the lateral branches grew, 15-20 d of shade were sufficient to cause a significant …

publication date

  • January 1, 1994

published in