Boron is a micronutrient critical to the growth and health of all crops. It is a component of plant cell walls and reproductive structures. Boron can be found in soil solution, adsorbed to soil surfaces, organic matter, and is part of soil mineralogy. Boron is a mobile nutrient, meaning that it is prone to movement within the soil.
Monoammonium phosphate (MAP) and diammonium phosphate (DAP) are excellent sources of phosphorus (P) and nitrogen (N) for high-yield, high-quality crop production. Research trials at 42 field sites in seven Corn Belt states showed an average corn yield of 162 bushels per acre with MAP and 159 with DAP. MAP (11-52-0) and DAP (18-46-0) contain about 90 percent water-soluble P, which is well above the 60 percent needed for optimum crop growth.
A variety of coatings have been applied to fertilizer particles to control their solubility in soil. Controlling the rate of nutrient release can offer multiple environmental, economic, and yield benefits.
Diammonium phosphate (DAP) is the world’s most widely used phosphorus fertilizer. It’s made from two common constituents in the fertilizer industry, and its relatively high nutrient content and excellent physical properties make it a popular choice in farming and other industries.
Scientists from Arizona State University compared fluid ammonium polyphosphate (10-34-0) applied in irrigation water with granular monoammonium phosphate (MAP) broadcast and irrigated into the soil as phosphorous (P) sources for high-yield alfalfa (eight cuttings per year) and to study movement and availability of P in a calcareous soil.
When it comes to phosphate source selection, the menu is a good one. It contains liquid sources, such as the polyphosphates 10-34-0 and 11-37-0; and granular sources such as monoammonium phosphate (also called MAP, which is 11-52-0) and diammonium phosphate (also called DAP, which is 18-46-0).
Monoammonium phosphate (MAP) is a widely used source of phosphorus (P) and nitrogen (N).*
Triple superphosphate (TSP) was one of the first high-analysis phosphorus (P) fertilizers that became widely used in the 20th century. Technically, it is known as calcium dihydrogen phosphate and as monocalcium phosphate, [Ca(H₂PO₄)₂ .H₂O]. Despite its excellent history as a P source, its use has declined as other P fertilizers have become more popular.