Roots Facing Water Deficit: Abscisic Acid Plays a Key Role in Mediating Stress Avoidance in Poplar

Plants exposed to water deficit often respond with a strong inhibition of shoot growth, while root growth is less inhibited or even promoted. In this study, abscisic acid (ABA) insensitive transgenic poplar (Populus x canescens) was used to test with sorbitol treatment whether ABA is involved in the control of differential root and shoot growth responses to water deficit. Results indicate that ABA influences radial root growth and plays an important role in stress avoidance under water defict.