Potato Yield Response to Select Phosphorus and Potassium Sources.

Title: Potato Yield Response to Select Phosphorus and Potassium Sources Authors: G. Thurgood, B. Hopkins Two of the most common forms of P and K fertilizer sold in the world are monoammonium phosphate (MAP; 11-52- 0) and muriate of potash [MOP; 0-0- 60-48(Cl)]. These fertilizers are relatively inexpensive and widely available. They are very soluble and have proven to be effective. A common form of B fertilizer is sodium borate (14.3% B) and a common form of Zn fertilizer is zinc sulfate (35.5% Zn). These are also soluble and effective fertilizers, but the disadvantage is related to the fact that they are micronutrients and only needed in very small quantities. Putting a blend of these fertilizers in a spreading truck often results in variable settling en route to a field due to differences in particle sizes and densities. Additionally, spreading can be variable, especially for applicators that use a rotary spread mechanism. Also, the number of fertilizer prills per square foot is very small, which can result in some plants receiving the micronutrients and others notÑespecially for plants with limited root systems (such as carrot, onion, turfgrass, and potato). MicroEssentials¨ SZª (MESZ; 12-40- 0-10S- 1Zn) is an alternative to MAP and zinc sulfate. It fuses nitrogen (N), P, sulfur (S), and Zn into a single granule. The Aspire¨ product (0-0- 58-0.5B) is an alternative to MOP and sodium borate. It is a fusion of K and B into a single granule. Each granule of fertilizer contains roughly the same concentration of these essential nutrients. Everywhere a granule falls will release the same amount of nutrients into the soilÑresulting in more consistent nutrient distribution. The objective of this trial was to evaluate these fertilizers in Russet Burbank potato for yield and tuber quality.