Nitrogen is the chemical element with the symbol N and atomic number 7. It was first discovered and isolated by Scottish physician Daniel Rutherford in 1772. It is a colourless, odourless, tasteless gas that is the most plentiful element in Earth’s atmosphere and is a constituent of all living matter.
Nitrogen is in the soil under our feet, in the water we drink, and in the air we breathe. Nitrogen is important to all living things. It plays a key role in plant growth: too little nitrogen and plants cannot thrive, leading to low crop yields; but too much nitrogen can be poisonous to plants.
When plants lack nitrogen, they become yellowed, with stunted growth, and produce smaller fruits and flowers. Farmers may add fertilizers containing nitrogen to their crops, to increase crop growth. Without nitrogen fertilizers, scientists estimate that we would lose up to one third of the crops we rely on for food and other types of agriculture.