Which plant feature influences absorption of herbicides by acting as a barrier?

Which plant feature influences absorption of herbicides by acting as a barrier?

• A. Thick, waxy leaf cuticle
• B. Root depth
• C. Stem thickness
• D. Flower color

Answer: (A)

The leaf cuticle is the main barrier to herbicide absorption. This thick, waxy, hydrophobic layer on the epidermis slows or blocks molecules from penetrating into leaf tissues, so a plant with a thicker, more waxy cuticle will take up less herbicide from foliar applications. Other features like root depth or stem thickness don’t act as barriers to leaf- surface absorption, and flower color has no bearing on herbicide uptake. Adjuvants can help improve penetration by aiding spreading and wetting, but the cuticle remains the primary obstacle to foliar absorption.

The leaf cuticle is the main barrier to herbicide absorption. This thick, waxy, hydrophobic layer on the epidermis slows or blocks molecules from penetrating into leaf tissues, so a plant with a thicker, more waxy cuticle will take up less herbicide from foliar applications. Other features like root depth or stem thickness don’t act as barriers to leaf- surface absorption, and flower color has no bearing on herbicide uptake. Adjuvants can help improve penetration by aiding spreading and wetting, but the cuticle remains the primary obstacle to foliar absorption.