ABT46103 Lecture 7

What is the primary entry point for foliar-applied herbicides?

• Stomata

• Roots

• Cuticle

• Phloem

Which pathway allows herbicides to move freely through cell walls and intercellular spaces?

• Symplast

• Apoplast

• Endodermis

• Xylem

Which type of herbicide movement involves the transport of substances via the cytoplasm of interconnected cells?

• Passive transport

• Symplastic transport

• Apoplastic transport

• Active transport

Systemic herbicides use which plant tissue for long-distance transport?

• Xylem

• Phloem

• Epidermis

• Mesophyll

What feature of the casparian strip in roots affects herbicide transport?

• It prevents apoplastic movement.

• It enhances xylem flow.

• It promotes passive diffusion.

• It accelerates transpiration.

Herbicides applied to the soil are absorbed by the roots and transported primarily through the ________ tissue.

A farmer applies a systemic herbicide to control weeds in a drought-prone area. Explain how limited water availability might affect the absorption and transport of the herbicide.

Answer explanation

Limited water availability reduces the plant's ability to absorb the herbicide, as water is essential for the uptake and transport of chemicals within the plant. This can lead to decreased effectiveness of the herbicide.