72. Optimization of NPK combination for seed production of onion (Allium cepa) crop

Abstract

Low productivity along with extensive usage of onion may cause shortage of this crop, as our country is facing high population problem. Mainly, there are two causes of low yield, lack of improved production technologies and poor quality of seed. Moreover, nutrient management is also an important aspect for getting higher yield. The current trial was conducted in RCBD with three replications and eight treatments. Treatments included different NPK fertilizer combinations i.e. T₁: Control, T₂: 30-20-00, T₃: 60-40-15, T₄: 90-60-30, T₅: 120-80-45, T₆: 150-100-60, T₇: 180-120-75, T₈: 210-140-90 kg NPK ha^-1 and three replications. Data on multiple parameters viz. time to sprouting (days), number of shoots (plant^-1), leaf length (cm), flowering stalk (plant^-1), stalk length (cm), number of flowers (umbel^-1), umbel diameter (cm), 1000-seed weight (g), seed yield (kg ha^-1) were collected and statistically analyzed. It was noticed that increment of fertilizer rates delayed sprouting but increased the number of shoots, leaf length, flowering stalks, length of flowering stalks, flowers (umbel^-1) and umbel diameter in onion cv. Shah Alam. Highest fertilizer dose (T₈:210-140-90 kg NPK ha^-1) showed its superiority by producing maximum shoots (6.48 plant^-1), longest leaves (41.20 cm), longest flowering stalk (67.10 cm), flowers (372.22 umbel^-1), umbel diameter (6.45 cm), seed weight (3.03 g) and seed yield (420.0 kg ha^-1). But almost all these parameters were statistically similar with T₇: 180-120-75 kg NPK ha^-1, hence, it is recommended that T7 and T8 should be used for getting maximum onion production.

Keywords: Allium cepa; Flowering stalk; NPK; Onion; Seed weight; Seed yield; Umbel

http://dx.doi.org/10.19045/bspab.2019.80117