INFLUENCE OF PLANT DENSITY AND FERTILIZATION ON THE GROWTH AND SEED YIELD OF BUNCHING ONION

Abstract

A field experiment was conducted in the field of Sher-e- Bangla Agricultural University, Dhaka, Bangladesh during the period from November 2020 to April 2021. The experiment consisted of three levels of spacing (viz. S 1 I = 20cm×10cm, S 2

= 20cm×15cm, S 3 = 20cm×20cm) and four levels of fertilizer (viz. F 0 = No application (control), F 1= N 57.5kg P 66kg K 45kg S 10kg V 6t/ha , F 2 = N 57.5kg P 66kg K 45kg , F 3= N 115kg P 132kg K 90kg S 20kg V 3t PM 3t/ha ). The two-factor experiment was carried out in Randomized Complete Block Design (RCBD) with three replications. There were 12 treatment combinations in this study. A unit plot was 1.2 m×1.2 m and the treatments were distributed randomly in each block. Data on growth and yield parameters were recorded and analyzed statistically. Growth and yield of bunching onion were influenced by the different spacing. The 20cm×20cm spacing resulted in the highest number of leaves, dry matter content in leaves, umbel diameter, number of seeds per umbel, thousand seed weight and percent of gemination. The maximum seed yield per hectare (1065 kg) was observed in 20cm×10cm spacing. Different levels of fertilizer had also significant influence on yield of bunching onion. The highest plant height, number of leaves, length and diameter of flower stem, umbel diameter, seed yield per plot and per hectare (157.48 g/plot and 1056.3 kg/ha, respectively), number of flowers per umbel, number of seeds per umbel, thousand seed weight and percent of gemination were found from the N 115kg P 132kg K 90kg S 20kg V 3t PM 3t/ha treatment. The highest seed yield (1260 kg/ha) with net income (Tk.699991.4) and BCR (2.26) were observed from S 1 F 3 treatment combination, while the lowest were from S 3

treatment combination. So, economic analysis revealed that the S 1 treatment combination appeared to the best for achieving the higher yield and economic benefit of bunching onion.