Peranan Pupuk Magnesium–Sulfur (Kieserit) dalam Memperkuat Efisiensi Pemupukan NPK dan Produktivitas Jagung Manis pada Inceptisol

Abstrak

Modern agriculture largely depends on NPK fertilization however, the neglect of secondary 
nutrients, particularly magnesium (Mg) and sulfur (S), has increasingly led to nutrient imbalances and
reduced fertilizer efficiency. Magnesium plays a crucial role in photosynthesis, energy transfer, and
enzyme activation, and its deficiency often referred to as the “forgotten element” has become more
prevalent in intensive cropping systems and leached mineral soils. This study aimed to evaluate the
role of magnesium–sulfur (Mg–S) fertilizer derived from kieserite in enhancing the growth and yield
of sweet corn (Zea mays saccharata L.) cultivated on Inceptisol soil. This study used a Randomized
Block Design (RBD) with seven different combination treatments between kieserite (½; ¾; 1; 1 ½ and
NPK (¾ and 1) recommended dosages, one treatment recommendation dose of local farmer and one
treatment without fertilizer for comparison. Each treatment was replicated three times, resulting in a
total of twenty-seven experimental plots. Soil chemistry parameters as a main object of this
experiment. The results of this study showed that the application of kieserite inorganic fertilizer
significantly improved N, P, K, and Mg concentrations in plant tissue, increased total soil Mg content,
and enhanced yield components of sweet corn compared to the control and standard NPK treatments.
The combined application of one dose of kieserite (300 kg ha⁻¹) and the recommended NPK rate (350–
100–50 kg ha⁻¹) produced the highest yield, reaching 14.24 t ha⁻¹, indicating that balanced Mg–S
supplementation is essential for optimizing nutrient efficiency and maximizing sweet corn
productivity on Inceptisol soils.