SURFACTANT-INDUCED PHYTOTOXICITY

The leaves of tall morningglory, giant duckweed, and common purslane were treated with nine surfactants at a concentration of 0.1% and examined after 24 hr using cryo-scanning electron microscopy for phytotoxicity as evidenced by tissue damage and epicuticular wax morphology changes. In some instances, tissue damage could be discerned; however, the effects of a particular surfactant were not uniform across the three species. Morphological alteration of epicuticular waxes was not observed. Gas chromatographic analyses of the epicuticular waxes of the species used in the study reveal component differences and may, in part, explain the lack of uniform response across species for a particular surfactant. Nomenclature: Tall morningglory, Ipomoea purpurea (L.) Roth #3 PHBPU; common purslane, Portulaca oleracea L. # POROL; giant duckweed, Spirodela polyrhiza (L.) Schleid. # SPIPO.