Nitrogen (N) constitutes for all plants the pivot of metabolism, basic element of cell multiplication and growth of plant organs. The vine is no exception, as the element is indispensable for its development and necessary from the beginning and throughout the entire period of activity of the plant.
The nutrient is an important constituent of amino acids and proteins. Free amino acids give rise to other amino acids and proteins and, consequently, to enzymes and coenzymes (NaDPH and NADP); they are precursors of plant hormones – tryptophan from AIA and methionine from ethylene; porphyric nuclei – chlorophyll and cytochromes; nitrogen reserve in seeds – asparagine and arginine; vitamins; nitrogenous bases (purine and pyrimidine); nucleotides and by polymerizing them to nucleic acids – DNA and RNA, glyco and lipoproteins; pigments and by-products. It participates in photosynthesis, respiration, biosynthesis, cell multiplication and differentiation, and genetic inheritance.
Deficiency – The first symptoms of deficiency appear on older leaves. The main symptoms of nitrogen deficiency are: decreased plant growth; reduction in the size of the leaves (dwarfism), which have a pale green tone tending to yellow (chlorosis), necrotizing and easily detaching from the branches; shortening of internodes; less development of the root system and low fertilization of the bunches. The main symptoms of nitrogen deficiency are: decreased plant growth; reduction in the size of the leaves (dwarfism), which have a pale green tone tending to yellow (chlorosis), necrotizing and easily detaching from the branches; shortening of internodes; less development of the root system and low fertilization of the bunches. The main symptoms of nitrogen deficiency are: decreased plant growth; reduction in the size of the leaves (dwarfism), which have a pale green tone tending to yellow (chlorosis), necrotizing and easily detaching from the branches; shortening of internodes; less development of the root system and low fertilization of the bunches.
