Effect of various varieties and dosage of potassium fertilizer on growth, yield, and quality of red chili (Capsicum annuum L.)

Red chili is one of the important commodities with increasing demand. However, the quality, continuity of supply, and quantity have not been realized to meet domestic market demand. Increasing growth, yield, and quality can be pursued through superior varieties, and the effort to increase crop productivity is the application of various doses of potassium fertilizer. Therefore, this study aimed to determine the effect of various varieties and doses of potassium fertilizer on the growth, yield, and quality of red chili. The split-plot experimental design consisting of two factors was also used. The first factor is the variety, as the main plot consisting of UNPAD CB2, Tanjung 2, and Lingga. The second factor was the dose of potassium fertilizer as sub-plots which consisted of four levels, namely 0, 100, 200, and 300 kg/ha KCl. The results showed an interaction between variety and dose of potassium fertilizer on plant height at 8 weeks after planting (WAP), stem diameter at 8 WAP, and leaf area index at 9 WAP. Meanwhile, UNPAD CB2 showed the best results for 6 WAP plant height, fruit weight per plant, number of fruits per plant, fruit length, dihydrocapsaicin, total capsaicinoid, and scoville heat unit. Potassium fertilizer doses of 200 and 300 kg/ha KCl showed high yields for stem diameters of 6 WAP.