Overexpression of PtADC confers enhanced dehydration and drought tolerance in transgenic tobacco and tomato: effect on ROS elimination.

Drought is a major environmental factor that limits plant growth and productivity. Polyamines have been shown to act as stress molecules that accumulate in plant adaptation to abiotic stresses. In this study, an arginine decarboxylase gene isolated from Poncirus trifoliata, PtADC, was introduced into tobacco and tomato to investigate its function in drought tolerance. We demonstrate that the transgenic plants showed an improvement in dehydration and drought tolerance. Under dehydration stress conditions, the accumulation of reactive oxygen species (ROS) was remarkably decreased in the transgenic lines as compared with the wild type. Moreover, the transcript levels of three stress-responsive genes were increased in the transgenic tobacco lines. Taken together, our results suggest that PtADC plays a key role in drought tolerance, which is, at least partially, attributed to its role in ROS detoxification.