In conclusion, the positive effect of water
stress and subsequent re-watering on water and K+
transport in excised sunflower roots indicated the existence of mechanisms
enabling the perception of water stress. These mechanisms may
activate transduction processes that control the transport of water
and K+ from the root to the shoot in plants with low transpiration.
This could contribute to a rapid recovery of the shoot water status,
cell turgidity and thus plant growth. On the basis of the available
data, this phenomenon can be described, but its underlying causes
cannot be clarified in detail