Effect of Kelpak Plant Growth Regulator Soaking and NPK Fertilizer Dosage on the Germination and Growth of True Shallot Seedlings (Allium cepa L.)

This study investigates the effect of Kelpak plant growth regulator (PGR) soaking and varying dosages of NPK fertilizer on the germination and growth of True Shallot Seeds (TSS) of Allium cepa L. The experiment was conducted from February 2 to May 3, 2024, in Bodag Hamlet, Bandungharjo Village, Grobogan Regency, Indonesia, using a Completely Randomized Block Design (CRBD) with two treatment factors and three replications. The first factor was Kelpak PGR soaking at four concentrations: 0, 1, 2, and 3 mL/L (J0–J3). The second factor was NPK Mutiara fertilizer application at rates of 0, 100, 200, and 300 kg/ha (K0–K3). Data were analyzed using analysis of variance (ANOVA) and least significant difference (LSD) at the 5% level. Parameters observed included germination rate, root length, plant height, leaf number, tuber number per plant, tuber weight per plant, and total yield per plot. The findings indicate that the combination of 1 mL/L Kelpak soaking (J1) and 300 kg/ha NPK application (K3) yielded optimal seedling growth and tuber development.