Potassium fertilization enhances pepper fruit quality

The effect of potassium (K+) concentration on the nutritional quality and yield of pepper fruits was evaluated. Pepper plants were grown in a controlled-environment greenhouse under hydroponic conditions with different nutrient solutions obtained by modifying the Hoagland solution to achieve different K+ concentrations. Potassium nutrition affected fruit yield parameters more than vegetative biomass in pepper plants. The maximum fruit yield was obtained with 7 mM K+ in the nutrient solution. However, it is possible to improve the bioactive compounds of pepper fruits with a higher application of K+ without reducing yield. The increase of K+ in the nutrient solution improved pepper fruit quality by increasing fruit firmness, TSS content, soluble sugars and ascorbic acid concentration. Therefore, the fruit quality improvements obtained with adequate K+ nutrition resulted in nutritionally enriched fruits, which, at little or no extra cost, benefits the consumer.