Root water conductivity of some herbaceous species.

In this study, the values of water conductivity of roots are reported for eleven crops and grapevine. For some crops, two methods (pressure chamber and transpiration method) were compared. The effects of salt and water stress were evaluated on different crops , as the effect of chloride mercury treatment, nitrogen deprivation and the interactive effects of salt, water, nitrogen and mercury stress. Root water conductivity was evaluated, for almost all the crops, during the whole plant cycles. The transpiration method always showed values of root water conductivity higher than the pressure chamber. In almost all the species, the mercury chloride reduced root water conductivity during all the plant cycle. Nitrogen deprivation and salt stress induced higher root water conductivity reduction than mercury stress. Water stress induced also a reduction but its effect on root water conductivity was lower than that of nitrogen and salt stress. Mercury chloride treatment did not show any effect on nitrogen and salt stressed plants, while in the water stressed plants its effect was additive