Besides the cuticle, which leaf feature influences herbicide absorption?

Besides the cuticle, which leaf feature influences herbicide absorption?

• A. Stomates
• B. Veins
• C. Chloroplasts
• D. Epidermis

Answer: (A)

Stomatal openings on the leaf surface provide a direct route for foliar herbicides to enter the leaf interior, in addition to the protective cuticle. When these pores are open, liquids can bypass much of the waxy barrier and move into the substomatal space and underlying tissues, increasing absorption. Veins are mainly for internal transport once a compound is inside the leaf, not for initial entry from the surface. Chloroplasts are internal organelles involved in photosynthesis and don’t influence how a chemical crosses the leaf surface. The epidermis is the outer protective layer that includes the cuticle, but the specific factor that directly controls absorption besides the cuticle is the presence and openness of stomata.

Stomatal openings on the leaf surface provide a direct route for foliar herbicides to enter the leaf interior, in addition to the protective cuticle. When these pores are open, liquids can bypass much of the waxy barrier and move into the substomatal space and underlying tissues, increasing absorption. Veins are mainly for internal transport once a compound is inside the leaf, not for initial entry from the surface. Chloroplasts are internal organelles involved in photosynthesis and don’t influence how a chemical crosses the leaf surface. The epidermis is the outer protective layer that includes the cuticle, but the specific factor that directly controls absorption besides the cuticle is the presence and openness of stomata.