Nitrogen and magnesium are inorganic nutrients used in fertilisers in some areas to support plant growth.
Nitrogen is amongst some of the main elements that are supplemented via fertilisers, alongside potassium and phosphate. Magnesium is considered a trace element rather than a main element.
Plant metabolism, with a key focus on photosynthesis, underlies the use of these fertilisers.
Nitrogen is one of the 4 main biological atoms, alongside carbon, hydrogen and oxygen. It makes up DNA and amino acids present in all proteins, hence underpinning every growth and reproductive function in plant cells and overall as organisms. Magnesium is only a trace element because it is found in chlorophyll. While not as abundant as nitrogen, it still serves a vital role because of the function of chlorophyll in photosynthesis. Therefore, it is important to ensure plants do not become deficient in this nutrient.
Nitrogen deficiency in plants can be observed if leaves are a pale green-yellow and the plant grows tall and thin. Too much nitrogen fertiliser (often based on ammonia) can cause fertiliser burn if the fertiliser contains too much nitrogen salt. This is diagnosed if leaves show scorching.
Magnesium deficiency on the other hand is present if the plant leaves are prematurely autumnal or dying, and towards the bottom part of the plant there are yellow discolorations between leaf veins.
These illustrate how the role of inorganic nutrients in plant metabolism are linked to the use of fertilisers containing nitrogen or magnesium supplementation in farming, industry, gardening, etc.