Phosphorus in Plants

There is no substitute for phosphorus in high-value crop production.

Phosphorus may not be first in the N-P-K lineup, but don’t underestimate its importance to plant growth and development. Many essential plant processes would not occur without it. There is no substitute for phosphorus if your primary goal is to maintain first-rate crops and high yields.

Every living plant cell contains phosphorus as part of the substances that carry the DNA code of living things. Phosphorus directly influences reproduction, photosynthesis, cell division, root development and energy storage. Some flowers and fruit also contain high concentrations of phosphorus.

Correct placement of phosphorus near the root zone is crucial because of its low mobility in the soil. The greater the distance the root must cover to reach the phosphorus, the greater the chance it will be unavailable when the plant needs it. Most plant roots only explore about 3% of the soil around them. Stunted growth, spindly stalks, distorted leaves and purpling are all signs of a phosphorus deficiency, as well as reduced blooms and/or onset of fruit.

In any given year, crops take up a combination of phosphorus applied in the current cropping year and phosphorus applied in previous years. Soil pH or acidity influence phosphorus reactivity and determines the speed and type(s) of insoluble phosphorus that is most likely to form. Phosphorus fertilizers are generally very inefficient and only a small portion of what is applied typically gets into the crop.

What’s new on the phosphorus front at Agro-Culture Liquid Fertilizers?

Pro-Germinator™ utilizes carbon as a building block to form long phosphorus chains that provide protection for the nutrient until the plant is ready to absorb it. The phosphorus compound isn’t subject to movement from the cropping environment because it reaches its intended destination the first time. This creates an optimum situation and leads to greater use efficiency.

Pro-Germinator™ performance is one of the standards that AgroLiquid uses to evaluate experimental phosphorus products. In 2012, researchers evaluated two experimental phosphorus fertilizers, SP-12 and ZP-12, on corn, soybeans and various vegetable crops. Both products, in addition to being N-P-K products, have added sulfur to help meet more complete crop requirements. This presented an increased risk for injury if the product comes into contact with the seed, unlike Pro-Germinator™, which is safe for in-furrow applications up to 10 gal/A on field corn.

Experimental Phosphorus Placement Options for Corn

This trial evaluated in-furrow and 2×2 placement options for effects on establishment, yield and stand. Pro-Germinator yields were similar for both application methods (197.2 vs. 194.5 bu/A). When comparing 2×2 applications, SP-12 and ZP-12 yields were numerically higher, but this did not hold true for in-furrow applications. Testing will continue to verify the conclusion that SP-12 and ZP-12 cause yield loss when applied in-furrow. (See Corn Planter Program Additives)

Corn Planter Additives

Experimental Phosphorus Applications on Soybeans

In-furrow and 2×2 applications of Pro-Germinator, SP-12 and ZP-12 were made with rebounders or tubes in the bottom of the furrow. Averages on all locations show SP-12 increased soybean yield 2 bu/A over that of Pro-Germinator. This may be enough of an increase to continue further testing during the 2013 growing season.

Phosphorus On Soybeans

For the full research results see “Experimental Phosphorus Placement Options (NCRS 12-309, 719)” and “Experimental Phosphorus Fertilizers on Soybeans (NCRS 12-709, 1002, 1101)” in the 2012 Research Report.