Application of potassium fertilizer and plant growth regulators to the growth and productivity of purple sweet potato

The study aimed to determine the effect of plant growth regulators and potassium fertilizer on the growth and productivity of three clones of purple sweet potato. The experiment was conducted at IPB University experimental station in Leuwikopo Dramaga Bogor for seven months. The study used a split-plot design with three factors and three replications. The first factor was as a subplot, namely plant growth regulators (PGR) application which consisted of two levels of without PGR (S0) and with PGR (S1) concentration of 2 cc l-1 of water (2,000 ppm). The second factor was as a subplot, namely rates of potassium chloride fertilizer (60, 120, 180 kg ha-1 K2O). The third factor as the main plot was sweet potato clones of (K1) Ayamurasaki, (K2) RIS-03063-05, and (K3) MSU 03028-10. The concentration of 2,000 ppm PGR did not significantly affect growth and tuber yield components. Potassium chloride K2O of 60 kg ha-1 up to 180 kg ha-1 did not significantly affect growth and tuber yield components. MSU 03028-10 clone had the highest total tuber yield (1537.8), healthy tuber (1529.9), unmarketable tuber (740.3), and small tuber (709.0). MSU 03028-10 clones have the longest stem length and the largest number of leaves 3-12 WAP. This study indicates that the MSU 03028-10 clone produces better growth and productivity than other clones.