Abstract

This experiment assessed the influence of potassium (K) levels on the growth, yield and quality of potato with
a focus on determining the optimal potassium application rate. The experiment was conducted in a randomized
complete block design in JICA, Tsukuba International Center, Ibaraki, Japan, from March 4, 2024, to July 12,
2024, on the Kitakari variety. There were four different levels (0, 75, 150 and 225 kg/ha) of potassium treatment
with three replications. The result showed a significant difference in plant height, stem number, marketable
yield, dry matter and starch level based on potassium level. The highest marketable yield (4.1 kg/m2) and
highest dry matter were observed at 150 kg/ha of potassium. Conversely, potassium levels of 225 kg/ha resulted
in larger tubers but decreased overall quality. The study concluded that 150 kg/ha of potassium optimizes
potato yield and quality. This finding recommended an application rate of 150 kg/ha for optimal growth and
yield in potato cultivation. Further research is suggested to validate these results across various geographical
conditions.
Keywords: Dry Matter, Nutrient Management, Potassium, Potato Yield, Tuber Quality