Meaning Any natural or manufactured item that is applied to soil or plant tissues to offer plant nutrients is referred to as a fertilizer or fertilizer. Nutrient soil chemicals are not necessarily fertilizers.
Fertilizers are organic or inorganic compounds that include chemical ingredients that help plants develop and improve soil fertility. The most significant plant nutrients are nitrogen, phosphorus, and potassium.
Inserting, drilling, or placing fertilizer below the soil surface with any tool or equipment at the right depth to supply plant nutrients to the crop is referred to as placement. It is done before sowing or in the standing crop.
In this category, the following approaches are the most common:
(a) Plough-sole Positioning:
During the pouching procedure, the fertilizer is applied in a continuous band on the bottom of the furrow. As the next furrow is turned, each band is covered. In most cases, no attempt is taken to sow the crop in a specific area about the plow sole bands.
i. In locations where the soil becomes quite dry up to a few inches below the soil surface throughout the growing season, and especially in soils with a thick clay pan a little below the plow-sole, this practice has been advised. Fertilizer is deposited in moist soil in this way so that it is more readily available to growing plants during dry seasons.
(b) Deep Positioning:
i. In Japan, this method of applying nitrogenous and phosphate fertilizers to paddy fields are widely used, and it is also advised in India.
ii. To avoid nitrogen loss in lowland rice, an ammoniac nitrogenous fertilizer such as ammonium sulfate or ammonium forming nitrogenous fertilizer such as urea is put in the decreased zone. During the active vegetative period, it is available to the crop.
iii. Fertilizer placed deep or subsurface enables better distribution of the root zone and prevents loss due to surface dram-off. Depending on the local cultivation practices, deep placement can be done in a variety of ways.
Fertilizer is put under the plow furrow in the dry soil in irrigated tracts where water supply is assured before flooding the area and preparing it for transplantation. It is spread before pudding in locations where there isn't a lot of water in the field. The fertilizer is pushed deep into the root zone by paddling.
(c) Subsoil Positioning:
i. This refers to the use of heavy power machinery to apply fertilizers in the subsoil.
ii. In humid and sub-humid climates, where many sub-soils are acidic, this approach is advised. The amount of available plant nutrients is significantly low due to acidic circumstances. Fertilizers, particularly phosphatic and potassic, are applied in the subsoil under these conditions to promote root development.
(d) Localized Positioning:
i.The application of nutrients to the soil near the seed or plant is referred to as this method.
ii.When only a modest amount of fertilizer needs to be applied, localized placement is frequently used. Phosphorus and potassium fixation is reduced by localized implantation.
e) Blending in bulk:
i. It is the technique of combining two or more different fertilizers with diverse physical and chemical compositions without causing any negative consequences.
ii. To improve the physical state of the mixed fertilizer, additional ingredients known as "Fillers" and" Conditioners" are employed in this formulation. This fertilizer combination should be used as a top dressing.
(f) Contact or Drilling Location:
i.It refers to sowing seed and fertilizer at the same time.
ii.Fertilizer seed drills are widely used for drill placement in dryland agriculture.
(g) Band Positioning:
i.The fertilizer is applied to one or both sides of the seed or plant in continuous or discontinuous bands.
ii. Sugarcane, tobacco, cotton, castor, maize, and vegetables are examples of crops that benefit from this strategy.
h) Pellet Positioning
i. To avoid nitrogen loss, fertilizer, particularly nitrogen in pellet form, is applied to lowland rice.
ii. Soil and fertilizer are blended in a 1:10 or 15 ratio and distributed in the decreased zone as little pellets.
Liquid fertilizers have become increasingly popular in foreign countries as a means of fertilization.
(a) Begin with a simple solution:
Fertilizer solutions are usually made in modest concentrations.
i. It is made up of N2, P2 O5, and K2O in the ratios of1:2:1 and 1:1:2 and is used for seed soaking, root dipping, and seedling spraying for early establishment and growth.
ii. The nutrients are immediately absorbed by the plant roots.
iii. The solution has been suitably diluted to prevent growth inhibition.
iv. Pulses and vegetable crops have particularly suited to this strategy.
Foliar Spray (b):
In this procedure, nutrients are sprayed over standing crops to help them recover quickly from the deficit. It prevents nutrient fixation in the soil.
A. Although foliar fertilization does not save much fertilizer, it may be preferable in the following situations:
i. When there are visible signs of nutritional shortage in the early stages of deficiency.
ii. When soil physical and chemical conditions are adverse, fertilizer use efficiency is reduced (FUE).
iii. During periods of drought, when soil application is impossible due to a lack of moisture in the soil.
d) Application to the Soil:
Liquid fertilizers must be applied directly to the soil, which necessitates the use of specialized injecting equipment. Nitrogen solutions and anhydrous ammonia (a liquid under high pressure of 14 kg per square cm or higher) are sprayed straight into the soil.
i. If the substance is put around 10 cm below the seed, there is relatively minimal plant harm or ammonia waste. Nitrogen from ammonia will be lost if the application is too shallow. This technology makes it possible to use the cheapest nitrogen supply directly.
ii. Urine, sewage water, and shed washing are all poured directly into the field.
Fertigation is the use of fertilizer in conjunction with irrigation water in an open or closed system. Lined and unlined open ditches, as well as gated pipelines for furrow and flood irrigation, make up the open system. The most common closed systems are sprinkler and drip irrigation.
i. Fertigation uses nitrogen and sculpture as its primary nutrients.
ii. This reduces the cost of application and allows the use of less expensive water-soluble fertilizers.
The use of chemical fertilizers regularly can change the ph of the soil, increase pests, acidification, and soil crust, resulting in lower organic matter, humus, and beneficial organisms, stunted plant development, and even greenhouse gas emissions.
Integrated soil fertility management attempts to improve crop output by increasing the efficiency of agronomic nutrient usage. This can be accomplished by using grain legumes, which improve soil fertility by biological nitrogen fixation, as well as chemical fertilizers.