Preparation and Properties of Urea Slow Release Coated with Potassium Humate, Bentonite and Polyacrylamide as Compositely Fertilizer which Reflected on the Productivity of Wheat Crop

Abstract

A slow release of urea fertilizer has become a necessity since it reduces the loss of nitrogen. This can be achieved by using different types of coatings, like sulfur, starch and wax etc. In this study, the producing of urea coated with bentonite, polyacrylamide and potassium humate which working on the reduction of nitrogen loss as resultant of either leaching or valorization and minimize environmental pollution beside reduce the consumption of fertilizer. Also, improve soil chemical properties, its positive impact on the productivity of wheat crop, and total content of macronutrients. Lab experiments were performed to determine the best concentration of bentonite to coated urea such as percent coating which showed that percent coating was increased with increasing the concentration of bentonite. The dissolution rate was decreased with concentration of bentonite (2.5%) in combination with 0.1% polyacrylamide. Along with, the experiment of investigation of the water absorption showed the greater absorbency of water was shown at 2 and 2.5% bentonite. In addition to, the incubation experiment revealed that amount released from nitrogen at 10 and 15 days were greater, which lasted for up to 20 days in urea uncoated than urea-coated. The concentration of 2.5% of bentonite seems to be favorable than other concentrations. These experiments conformed that the suitable quantity used in the coating urea by bentonite and polyacrylamide. Through an infrared (FTIR) diagnosis of the urea coated, its properties were identified at different wavelengths. The functional groups such as phenol, carboxyl, etc. which affect the compound's effectiveness when the urea associates with bentonite, polyacrylamide and potassium humate as one compound. Concerning, trial experiment were laid out at El-Ismailia Agriculture Research Station Farm, Agric. Res. Center (ARC), Egypt. At two successive seasons who's planted with wheat crop (Triticum aestivum L., CV. Giza 168) in a sandy soil under sprinkler irrigation system. To evaluate urea's coated beneficial effect on soil along with plant productivity. Established by the following transactions three rates of nitrogen 100, 75 and 50% from recommended dose of uncoated urea, urea formaldehyde and urea coated. Results show that, mean values of soil pH were decreased with urea formaldehyde and urea coated compared to uncoated urea (control), this inversely with values of EC in soil where increased with coated urea compare to other treatments in two seasons. Data revealed an increases of N,P and K availability in soil under impact of coated urea and urea form compared to control (uncoated urea) treatments with consideration that urea coated was superior than urea form. Regarding the plant behavior, results revealed that the mean values of the biological yield, grains and straw of wheat crop under impact of coated urea and urea formaldehyde treatments were increases compared to uncoated urea in two seasons. But it was observed that this increase was better when applying urea coated. Finally, this produ...

Review: Modified Urea Fertilizers and Their Effects on Improving Nitrogen Use Efficiency (NUE)

“…The nitrogen is released slowly, and the rate of release can be controlled, which means that the plants receive the nitrogen they need when they need it and can absorb it over a more extended period. This reduces the need for frequent fertilization, costs, time, and energy in terms of economic advantage [66][67][68].…”

Mineral Nitrogen Release Patterns in Various Soil and Texture Types and the Impact of Urea and Coated Urea Potassium Humate on Barley Biomass

“…Humic substances are a type of macromolecular natural organic matter that comprises a polyelectrolyte with a negative charge [36][37][38] that comprises a polyelectrolyte with a negative charge [36][37][38]. This polyelectrolyte is characterized by the presence of a hydrophobic core and a diverse array of functional groups such as quinone, aldehyde, carboxyl, phenolic, and alcoholic hydroxyls, as well as ether [35,36,[39][40][41]. Moreover, humic acid contains unbound carboxylic and amide groups, which demonstrate chelating capability, dispersibility, and adsorption when humic acid is used as a polymer [37,38].…”

“…According to previous studies, it has been reported that combining urea with potassium humate can improve nitrogen use efficiency and mitigate losses through volatilization or leaching [35,39,40,43,44]. The application of a combination of urea with humic compounds enhances nitrogen transformation to the ammonium form NH 4 + -N rather than the ammonia form NH 3 , which would be expected to reduce environmental damage [22,34,39,40].…”

“…According to previous studies, it has been reported that combining urea with potassium humate can improve nitrogen use efficiency and mitigate losses through volatilization or leaching [35,39,40,43,44]. The application of a combination of urea with humic compounds enhances nitrogen transformation to the ammonium form NH 4 + -N rather than the ammonia form NH 3 , which would be expected to reduce environmental damage [22,34,39,40]. The higher bond strength with higher concentrations of humate can slow the release of urea into the ammonium form, which then also slows its conversion into the nitrate form, leading to lower N losses [34,37,39,41].…”

“…Coating urea with humate leads to a stable product [39] with controlled nitrogen release [39][40][41]. However, the effectiveness of this combination may vary depending on the soil type [19,54].…”