Enhanced Efficiency Potassium Fertilizer in Soybean and Cotton Crop

Adequate plant nutrition is very important to soybean and cotton crops to express its potential production. Among plant nutrients, potassium (K) plays an important role in plants to achieve high yields. Potassium fertilization is an important tool for soybean and cotton high yields achieving because K absence reduces foliar K content and plant growth. Several strategies have been used to increase the efficiency of K fertilization. Among them, the use of enhanced efficiency K fertilizers has been studied more often recently. Owing to the lack of information related to the use of enhanced K fertilizers, the present study aimed at evaluating potassium leaching and soybean and cotton K foliar content, yield and agronomic efficiency in response to K rates and sources. To evaluate K leaching, a factorial 3×10 (three K sources and 10 irrigations levels) was carried out, under greenhouse conditions. Three soybean field trials and one cotton field trial were carried out to evaluate soybean K foliar content, soybean 100-grain weight, cotton 10-balls weight, K agronomic efficiency and yield. Increasing irrigation levels increased potassium leaching, which was mitigated by the Policote coated K fertilizer. Potassium fertilization increased soybean and cotton yields. Higher potassium agronomic efficiency index with Policote coated KCl explained higher yields obtained with this enhanced efficiency K fertilizer. Results show that Policote coated fertilizer is a more efficient way to deliver required potassium to plants. The use of enhanced efficiency fertilizers is an emerging technology to increase the potassium use efficiency of crops in the field. The observed changes in potassium use efficiency among potassium fertilizers increased our understanding of enhanced efficiency fertilizers.