Plastic films on plants as antitranspirants.

Plastic-film-type antitranspirants are more permeable to water vapor than to carbon dioxide. Photosynthesis in treated plants is reduced to the same or greater extent than transpiration, except under conditions of stress, when photosynthesis in treated plants is greater than in controls. This exception is attributed to reduction of stress, as the selective permeability of the films to gases would tend to produce the reverse effect.