ICL PotashpluS Benefits Soybean in Brazil

When there’s a lot to do, sometimes the finest of details can get overlooked. Take soybean growing in Brazil. Research has shown that, especially on the large-scale soybean fields, investing some attention to fine-tuning the fertilizer strategy for the crop can give a real boost to yields.  

Producing More Soybean from the same Land Area

Brazil’s phenomenal soybean productivity is well recognized, with production reaching in excess of 120 million tonnes a year, or about 3.3 t/ha. However, there is a limited to the land that can be dedicated to the crop, so farmers need to ensure they can maintain, or better still increase, soybean yields. So where could the yield come from? Recent research suggests that a carefully balanced fertilizer strategy, particularly with regard to sulfur and potassium may be the answer.  

Investigating Benefits of Different Sulfur Sources

A research team at the Rio Verde Research and Technological Development Foundation designed an experiment in collaboration with the International Potash Institute (IPI) to investigate the benefits of applying adequate potash and sulfur using ICL PotashpluS^®. A granular fertilizer made from combining Polysulphate and KCl, ICL PotashpluS is one of the ICL PLUS line of premium fertilizers. This research compared ICL PotashpluS with alternative sulfur fertilizers commonly used on soybean in Brazil (see table for details).  

Different sulfur sources investigate in soybean research

Treatment	Pre-planting broadcast		Applied at sowing
	KCl (MOP)	ICLPotashpluS®	MAP	Urea	NPK 8-40-0	SSP	PES
	kg/ha	kg/ha	kg/ha	kg/ha	kg/ha	kg/ha	kg/ha
MAP	-	-	154	-	-	-	-
MAP+KCl	134	-	154	-	-	-	-
MAP+SSP+KCl	134	-	69	20	-	245	-
MAP+PES+KCl	134	-	154	-	-	-	22
MAP+ICLPotashpluS®	-	217	154	-	-	-	-
NPK 8-40-0+KCl	134	-	-	-	200	-	-
Abbreviations: MAP: mono-ammonium phosphate; KCl: potassium chloride; MOP: muriate of potash; SSP: single superphosphate; PES: pastille elemental sulfur; NPK: composite N-P-K fertilizer with determined N-P2O5-K2O.

  The experiment took place in the Cerrado region, at Rio Verde Foundation in Mato Grosso state. The soil was a Red-Yellow Latosol, moderately acidic with low natural fertility. The experiment included six fertilizer treatments in a completely randomized block design with four replications. The rates of N, P₂O₅ and K₂O applied in all treatments were 17, 80 and 80 kg/ha, respectively, while the S rate was 20 kg/ha, adjusted according to the experiments fertilizer blends.  

Revealing the Potential of Sulfate Fertilizers

Of the different treatments tested, the treatments with sulfate as their sole source of sulfur – monoammonium phosphate (MAP) with ICL PotashpluS^®, and MAP with single superphosphate (SSP) and KCl – showed greater response potential. Both gave rise to significantly higher yields (10%) compared with common fertilizers where partial or total sulfur supply was in the elemental form. ICL PotashpluS^® broadcast pre-planting was as efficient as the SSP applied in the planting furrow.  

 

Efficient use of Time resulting in Better Crop Performance

Practically, large scale farmers gain other benefits from using ICL PotashpluS. The soybean-sowing window is small. That leaves the farmers of the Brazilian Cerrado racing to get the crop in between mid-October and mid-November. ICL PotashpluS is faster to apply and therefore increases the proportion of the crop sown in the ideal time which leads to better crop performance. ICL PotashpluS^®, now available to soybean farmers in Brazil, is a granular fertilizer formulated using a combination of Polysulphate and potash (MOP or KCl). While primarily a potash and sulfate fertilizer, it also contains essential magnesium and calcium, and supplies all the crop’s potassium and sulfur requirements in a single application. The formula is 37% K₂O, 9% S (24% SO₃), 3% MgO and 8% CaO. Encapsulated in the same granule, nutrient segregation is avoided, even when fertilizer is broadcast at pre-planting. Sulfur, magnesium, and calcium are all in sulphate (SO₄) form, ensuring high availability to plants. ICL PotashpluS^® ensures a progressive supply of sulfur during the whole crop cycle due to the prolonged solubility pattern of Polysulphate which reduces the risk of sulfur leaching. There is much more to this story. The full report “Evaluation of Potassium and Sulfur Fertilizers for Soybean in Brazil” is published in the e-ifc by the International Potash Institute (IPI). Photo credit: Fundaçao Rio Verde