Influence of Antitranspirants on Rapeseed (Brassica campestris) Plants under Water-stressed and Nonstressed Conditions.

Daily transpiration rate was decreased by low soil moisture, phenylmercuric acetate (PMA) in combination with kaolinite, Mobileaf (a filmforming wax emulsion manufactured by the Mobil Oil Co.), PMA alone, and kaolinite alone in this order. At high soil moisture, dry matter was decreased by PMA but was increased by Mobileaf and by PMA + kaolinite combination. At low soil moisture, dry matter was increased by Mobileaf.Water use efficiency was increased at low soil moisture and by antitranspirants. The relative water content of leaves was reduced by low soil moisture but was increased by the antitranspirants which relieved plant water stress.