ABSTRACT
This chapter provides results concerning the effects of an ethopropoxylated fatty amine on the penetration of 14C-glyphosate, N(phosphonomethyl)glycine, across isolated tomato fruit cuticles used as a model of the plant cuticle. Cuticular discs were isolated from mature tomato fruit at 35°C using a mixture of 2% pectinase and 0.2% cellulase at pH 3.8. The cuticles were washed several times with deionized water after their separation, then air dried and stored at room temperature. The efficiency of the separation method was checked by observing the internal surface of the isolated cuticles by scanning electron microscopy. The penetration of glyphosate across the cuticle greatly depended on the relative humidity and was always considerably greater at high rather than low humidity. The surfactant Armoblen 557 also facilitates penetration. Its main effect is attributed to the prolongation of favorable conditions on the cuticular surface, allowing the diffusion of glyphosate through a greater area to be continued after the apparent disappearance of the herbicide droplet.
