In cowpea (Vigna sinensis) enhancedelongation in response to EOD-FR is apparently due to reducedinactivation of GA1as a consequence of removal of the activephytochrome form Pfr(Martínez-García et al., 2000). In hybridaspen (Populus tremula × tremuloides) phytochrome A (PHYA) over-expression resulted in decreased shoot elongation due to reducedcell numbers and cell lengths, and this was correlated with reducedGA and IAA levels (Olsen et al., 1997).