Dr Ali very nice question . Simple increase in concentration of either NH3-NH4 nitrogen  or total N concentration of index leaves will give fair idea about the responsiveness of foliar application of arginine.  My counter question to your question   is,  why to test the foliar spray of arginine , when a better alternative  in form of foliar spray of low biuret urea is available. After application of low biuret urea , same nitrogen will get  converted  into arginine as first polyamine in the process of nitrogen metabolism.

Dear Anoop 

Thank you for question about low biuret urea ,the reason for using arginine  not low biuret urea related with the the situation of our country where these compound used in manufacturing  explusive weapon, so that these compount was not available in labs.

best regards

Ali Alhayany

Interesting Ali . Perhaps urea is more useful in explosives than low biuret urea?.  And , use  of arginine is far more costlier than any of these N-fertilizers.

Dr Ali . Simple analysis, concentration of  nitrogen  or same Amino acid , Protein

concentration also chlorophyll concentration,  Respiration to know the enzyme affected. 

Dear Anoop

Explosive is not my interest but I mean that these kinds of chemicals not available for researchers,so that we look for any substitute materials to achieve close results ,and i look for any traits can express if my treatments gave good results in the same linkof  low biuret urea foliar application .

Got your point of view Ali .But other options could perhsps costlier besides doubt on their effectiveness.