Nitrogen in agriculture

Nitrogen is a nutritional element of great importance for the growth and development of plants, when crops such as grasses have adequate amounts of this element, favorable characteristics can be observed in the plant, for example, in grasses such as guinea Megathyrsus maximus plants with good height and development of the tuft are seen, otherwise if there is a deficiency of this nutrient there may be a displacement of this element from the old leaves to the new tissues, turning with a yellowish color the areas from where the nitrogen has been displaced.

In that sense, it can be evidenced that it is necessary to have nitrogen availability in agroecosystems, but the largest amount of this element is found in the atmosphere, according to certain research reports by about 80%. The aforementioned makes us infer that there is a large amount of soils destined to agriculture with nitrogen deficiencies, according to Villalobos (2001), tropical areas are more prone to this situation because this element is not part of the parent material that originates the soil, and also because of the great susceptibility of the element to volatilization and leaching.

Logically, man for the supposed development of agriculture began to implement synthetic nitrogen products, which have been widely used, therefore, they are of high costs and also unbalance agroecosystems, among the commercial nitrogen fertilizer products are Urea (CO(NH2)2) which is the source with the highest percentage of nitrogen and the most economical, in the southern area of Lake Maracaibo it is used in different crops including grasslands when fertilizing, when this product is applied it must first be hydrolyzed and then goes through the process of nitritation and nitration with the help of certain bacteria, converted into nitrate can be easily absorbed by plants. There is also ammonium sulfate ((NH4)2SO4-) which has approximately 21% of the nitrogen, ammonium nitrate (NH4 NO3-) with 33% nitrogen in nitric and ammonium form, but some researchers point out that when it is applied and rains begin this can be lost by leaching, which can cause water pollution.

In the same vein, we should also mention that naturally there is the fixation of atmospheric nitrogen (N2) to the soil through the work done by certain bacteria of different genera such as rhyzobium and azotobacter that according to Parsons (2004), are able to take said nitrogen and reduce it to compounds available for crops. The activity is known as biological fixation that these microorganisms can perform freely in soil or through the process of symbiosis that they perform with the roots of some plants.

Currently, in search of rescuing organic agriculture and with the knowledge of the importance of these microorganisms for nitrogen fixation, commercial products have been developed with the strains of these bacteria, known as inoculants that, when incorporated into the soil, can increase the concentration of soil biota in the rhizosphere, increasing the possibility of nitrogen element fixation to be used by crops. That is, from these bacteria and their capacity biofertilizers can be produced; that they can improve the sustainability of crops, decreasing the need for synthetic nitrogen fertilizers. In short, according to Arauz (1997), biofertilizers arise from the practice of selecting useful and efficient microorganisms, growing them and adding them to soils.

Dear readers, as could be evidenced in agriculture due to the efficient response that was obtained in crops by applying a highly concentrated synthetic fertilizer, organic fertilization was displaced and with it the benefits it offers to the ecosystem such as the contribution of organic matter and beneficial microorganisms. Everything led producers to make excessive use of synthetic fertilizers, but gradually an ecological agriculture model based on sustainability has been rescued.