Sign up for email alerts of new Fluid Journal issues!
Fluid Journal : Fluid Journal 2005-2007
Early Spring 2006 Thiosulfates: A Reliable Source For Sulfur in Agriculture INDUSTRY AT WORK Thio-Sul (ATS) is one in a line of proven products marketed by Tessenderlo Kerley. Fluid Journal 1 Thiosulfates, primarily ammonium thiosulfate (ATS), have been used in agriculture for nearly a half century. Thiosulfates differ from sulfates in that they have an additional sulfur (S) atom in place of oxygen in their chemical structure. ATS has been the flagship of the Tessenderlo Kerley, Inc.(TKI) product line since its inception. The major use of ATS has been as a source of liquid sulfur in combination with urea-ammonium nitrate (UAN) solution for both improved nutrient-use efficiency (NUE) and better crop yields. In the brief space we have here let's take a look at a couple of other products we've developed and marketed to help growers more effectively produce crops. Potassium thiosulfate In November 1989, TKI began researching the possibility of using potassium thiosulfate (KTS) as a soluble source of potassium (K) for drip irrigation. The product was made commercially available in the spring of 1991. KTS is a clear solution containing 25 percent K2O and 17 percent S with a neutral to slightly basic pH. California had several hundred thousand acres of drip and micro sprinkler-irrigated crops with many of the soils low in K. When drip irrigated or micro-irrigated both row crops and permanent crops would, in a relatively short time, become K deficient. In vineyards, soil application of dry K fertilizer was also difficult, time consuming, and often, because of improper equipment, fertilizer was spread outside the wetted zone where it could not be effectively used by the crop. KTS has proved it lends itself well to this environment. On prune trees in Northern California, KTS introduced through irrigation water was twice as effective as K knifed into the soil at the drip line of the tree. Research by the University of California has shown that the addition of 4.5 lbs/A of K2O as KTS with a little nitrogen (N), foliar-applied at bloom, consistently increased cotton yields (Table 1). Calcium thiosulfate In 2000, TKI began production of calcium (Ca) thiosulfate (CaTS). It contains 6 percent Ca and 10 percent S with a neutral to slightly basic pH. It was initially developed for the irrigation market to improve water infiltration in slowly permeable soils, but other applications soon developed. Slow water infiltration is a major problem in California, causing losses of over $500/A for orchards because of standing water and water running off the fields. Application of CaTS to irrigation water lowers the sodium absorption ratio and increases electrical Treatment Rate/A Yield lbs lint/A Control 1,306 5-0-20 2.0 gal 1,573 * 5-0-20 + PGR IV*** 2.0gal+8.0oz 1,544 * 5-0-20 + Pix*** 2.0gal+8.0oz 1,639 * 5-0-20 2.0 gal 1,477 ** 5-0-20 + PGR IV*** 2.0gal+4oz 1,620 ** 5-0-20 + Pix*** 2.0gal+4oz 1,615 ** * 2 weeks after first bloom ** 2 and 4 weeks after first bloom *** plant growth regulator Table 1. Foliar potassium cotton trial.
Fluid Journal 2002-2004
Fluid Journal 2008-2009