The effects of potassium in pepper on plant nutritional element, plant growth and Rhizoctonia solani

Potassium enhances the resistance of plants to diseases by facilitating seed maturation and promoting the development of the root system. Among the essential nutrient elements necessary for plant growth and functions, potassium is the most effective element in reducing disease severity. This study aimed to determine the extent to which increasing doses of potassium affect the nutrient content, dry weight, root weight, and resistance against Rhizoctonia rot in the Klarnet F1 pepper plant. Pepper seedlings were used as plant material, and potassium sulfate was employed as the potassium fertilizer in the study. The experiment involved applying four different potassium doses (0, 5, 10, 15 kg/ha) to pepper seedlings, with disease inoculation conducted in four replicates. At the end of the study, analyses of N, P, K, Mg, Ca, Fe, Mn, Cu, Zn, dry weights, and root weights of the plants were performed, and disease assessments were made. An increase in N, P, K, Fe, and B contents was observed with applied potassium doses, while a decrease in Mg content was noted. No significant change was detected in Cu content in pepper leaves, and Mn content was not found to be statistically significant. An increase in plant dry weights was determined based on the applied treatments. The results indicated that plants provided with potassium exhibited resistance to disease, an increase in root weights, and overall better conditions compared to samples without potassium. The best results in the experiments were achieved with the application of 15 kg/ha K2SO4 hectare.