What is Glyphosate?

What is Glyphosate?

Glyphosate is the world's most widely used herbicide (a chemical designed to kill unwanted plants, or weeds). It is the active ingredient in numerous products, most famously **Roundup**, which was originally developed by Monsanto (now owned by Bayer AG).

1. How It Works: Mechanism of Action

Glyphosate is a **non-selective herbicide**, meaning it will kill most plants it comes into contact with. It works by inhibiting a crucial enzyme called **EPSP synthase**.

◆ Target Enzyme:** This enzyme is part of the **shikimic acid pathway**, which is essential for plants to produce three key aromatic amino acids (tryptophan, tyrosine, and phenylalanine).

◆ The Effect:** Without these amino acids, the plant cannot produce vital proteins necessary for growth. Glyphosate essentially starves the plant to death.

◆ Key Point:** The shikimic acid pathway does not exist in humans or animals, which is a primary reason for the initial belief that it had low toxicity to mammals.

2. Primary Uses

◆ Agriculture (The Biggest Use):** Glyphosate is a cornerstone of modern agriculture, particularly with the advent of **genetically modified (GM) crops**.

 *   "Roundup Ready" Crops:** Monsanto developed crops like corn, soy, cotton, and canola that are genetically engineered to be resistant to glyphosate. Farmers can spray entire fields with glyphosate, killing the weeds without harming the resistant crop.

◆ Pre-Harvest Desiccation:** Some farmers use glyphosate to dry out (desiccate) crops like wheat, oats, and barley right before harvest. This makes harvesting more efficient but can lead to higher residue levels in the food supply.

◆ Non-Agricultural Uses:** It is widely used in forestry, lawn care, golf courses, and by homeowners to control weeds in gardens and driveways.