It acts as a structural component of cell membranes, as well as being part of compounds responsible for the fixation of atmospheric CO2 and for the metabolism of sugars. Its main function is energy transfer.
It enters the composition of vitamins, lecithin, nucleic acids, adenosine diphosphate and triphosphate, which are energy carriers in the chloroplast. It is necessary for photosynthesis and carbohydrate metabolism.
Deficiency – The first symptoms appear on the older leaves of the vine. The characteristic symptoms of P deficiency are the development of marginal and interveinal red-violet coloration in the old leaves and the appearance of a red color in the petioles and in the main and secondary veins of the old leaves.