Abstract
As the result of the destruction of the global environment, the expansion of barren has recently become a social problem. Tree species tolerant to environmental stresses are expected to contribute the rehabilitation of barren. In the response of plant species to environmental stresses, ethylene is the factor involved in induction of senescence and injury. In this study, we examined the effect of decreased ethylene synthesis on the tolerance of transgenic poplar (Populus nigra var. italica) to environmental stresses.
An antisense gene of 1-aminocyclopropane-1-carboxylate synthase (ACS), a key enzyme of ethylene synthesis, was introduced and over-expressed under the control of the 35S promoter in poplar, resulting in decreased expression of endogenous ACS gene. In the response to ozone, drought and salt stress, leaf ethylene production induced by each stress was repressed in the transgenic poplar. Furthermore, although each stress brought about leaf necrosis in the wild-type poplar, visible injury was attenuated in the transgenic poplar, suggesting that the suppression of ethylene synthesis is effective in the improvement of tolerance to multiple environmental stresses.
