Nitrogen nutrition refers to the process by which plants absorb and utilize nitrogen, an essential nutrient for their growth. Nitrogen is a key component of amino acids, proteins, and nucleic acids, which are vital for plant development. Plants primarily obtain nitrogen from the soil in the form of nitrate (NO3-) and ammonium (NH4+), which are produced through the decomposition of organic matter and the activity of nitrogen-fixing bacteria. Proper nitrogen nutrition is crucial for healthy plant growth, as it influences leaf development, photosynthesis, and overall productivity. A deficiency in nitrogen can lead to stunted growth and yellowing of leaves, while excess nitrogen can cause excessive foliage growth at the expense of fruit and flower production. Balancing nitrogen levels is essential for optimal plant health and yield.