Nitrogen absorbed by roots as nitrate in most of the cases , undergoes a series of transformations like ammonium form then to various kinds of ployamines and amino acids to form variety of proteins eventually...

Plants take nitrogen from the soil by absorption through their roots as amino acids, nitrate ions, nitrite ions, or ammonium ions. Plants do not get their nitrogen directly from the air. ... Plants get the nitrogen that they need from the soil, where it has already been fixed by bacteria and archaea

Thanks sir for your informative explanation.

You have a great experience in plant nutrition sir but my question has another meaning.

I do agree with you regarding the soil Nutrient uptake but I have asked the mechanism of the foliar nutrition of nutrients.

In which form plant absorbs nitrogen when we apply nutrients through foliar spray like 1 Percent urea spray for deficiency of nitrogen.

I want to know that sir

Dr. Sagar SUBHASH More

The question should specify which category of plants are been referred to since aquatic plants, either submerge or emerged can uptake nitrates and ammonia through their leaves and green part of the stem. But as you mentioned the 'above ground parts', I assume your interest is with bonafide terrestrial plants and particularly due to highly pervasive nitrification in agricultural soil, crops mostly incorporate nitrogen as nitrates through root systems.But nitrate transporter are abundantly present n leaves of aerial/arboreal plants and have high affinity towards the NOx group of compounds

(Article Nitrate transporters in leaves and their potential roles in ...

Hence in spite of far greater uptake capacity through roots, plants do uptake nitrogenous compounds through leaf surfaces, albeit with reservation and limitations.

With regards,

Dr. Abhishek Mukherjee

Thanks Abhishek sir sharing very nice work on foliar nutrition of nitrogen and nitrate assimilation.

Actually sir you are right I am interested in terrestrial plants that's why I specifically added there above ground part of the plants.

And the mechanism of foliar application is very important according to the use effeciency of the nutrient application.

That's why I am interested in the foliar application mechanism.

Thanks alot sir for your valuable guidance.

With regards

Sagar

Long back we had an in depth discussion on plants differential ability to absorb nitrate versus ammonium form of nitrogen. Most of the terrestrial plants are turned to absorb nitrate form of nitrogen compared to ammonium form and in that process , plants have to spend much less energy while absorbing nitrate compared to ammonium form...

PFA, two documents regarding basics of foliar applied nutrients on above plant part.

Usually plants absorb nitrogen in NO3 form except paddy which can also absorb in NH4 form.