EFFECT OF NITROGEN AND POTASSIUM ON THE GROWTH AND YIELD OF ONION

Abstract

The experiment was conducted at the Research Farm of Sher-e-Bangla Agricultural University, Dhaka, Bangladesh in Rabi season during December 2019 to March 2020. The experiment was undertaken to investigate the effect of nitrogen (N) and potassium (K) on the yield of onion. Eight treatments viz. T 1 = N 0 P 45 K 0 S 30 Zn 3 B 1.5 = N 80 P 45 K 80 S 30 Zn 3 B 1.5 kg ha -1 , T 3 = N 100 P 45 K 80 S 30 Zn 3 B 1.5 (Control), T 2 kg ha = N 100 P 45 K 100 S 30 Zn 3 B 1.5 kg ha -1 , T 5 = N 120 P 45 K 100 S 30 Zn 3 B 1.5 kg ha = N 120 P 45 K 120 S 30 Zn 3 B 1.5 kg ha -1 , T 7 = N 140 P 45 K 100 S 30 Zn 3 B 1.5 kg ha = N 140 P 45 K 120 S 30 Zn 3 B 1.5 kg ha -1 were used in this experiment. The experiment was laid out in a randomized complete block design (RCBD) with three replications. Results of the experiment revealed that N and K significantly influenced yield parameters and yield of BARI Piaz-4. Among different treatments, T 7 performed the best in respect of all yield and yield contributing characteristics while the lowest value of those parameters was observed in the control treatment T 1 . The highest plant height (57.28 cm) at harvest was recorded in T 7 followed by T 8 (53.67 cm) treatment and the shortest plant (42.32 cm) being found in T 1 when the crop was not fertilized with N and K. The treatment T 7

produced the highest number of leaves plant -1 (12.00) at 70 DAP which was significantly higher than all other treatments. Among different treatments the highest leaf length (53.83 cm) was noted with T 7 at harvest which was statistically identical with and the lowest leaf length (39.67 cm) observed in T 1 treatment

at harvest. The maximum fresh weight of leaves plant -1 (35.2 g), dry matter content of leaves (16.83 %), diameter of bulb (5.57 cm), length of bulb (5.93 cm), fresh weight of bulb plant -1 (67.52 g), dry matter content of bulb plant -1 (14.33 %), yield plot -1 (10.92 kg) and bulb yield (21.83 t ha ) was noted in T 7 treatment. Therefore, it is concluded that the treatment T 7 (N 140 P 45

kg ha -1 ) may be recommended for maximizing the yield of BARI Piaz-4 at Tejgaon series soil of SAU Research Farm. -1 -1 , T 4 -1 , T 6 and T 8 -1 K 100 S 30 Zn 3 B 1.5