GROWTH AND YIELD OF LETTUCE (Lactuca sativa L.) AS INFLUENCED BY NITROGEN AND MULCHING

Abstract

n experiment was conducted al the farm of Sher-e Bangla Agricultural University, Dhaka, Bangladesh during the period from November 2006 to February 2007 to study the effect of nitrogen and mulching on growth and yield of lettuce. The experiment considered two factors. Factor A: Levels of nitrogen (4 levels) i.e. 0 kg N/ha (Control), 60 kg N/ha (N1), 80 kg N/ha (N2), I 00 kg N/ha (N3); Factor B: Mulching (4 levels) i.e. No mulch (M0), rice straw (M1), water hyacinth (M2), black polythene (M3). Data were collected in respect of the plant growth characters and green yield of lettuce at different days after transplanting. At 55 DAT the tallest (30.49 cm) plant height was recorded from N2, while control gave the shortest (24.04 cm) plant height. The maximum (28.01) number of leaves per plant was recorded from N3, while control gave the minimum (22.67) number of leaves per plant. The maximum (474.24 g) leaf yield per plant was recorded from N), while control gave the minimum (374.92 g) leaf yield per plant. The maximum ( 15.35%) dry matter content in plant was recorded from N2, while control gave the minimum ( 11.43%). The maximum (10.21 kg) yield per plot was recorded from N2, while control gave the minimum (7.88 kg) yield per plot. The maximum (42.56 t/ha) yield was recorded from N2 at 55 DAT, while control gave the minimum (32.85 t/ha) yield. At 55 DAT the tallest (31.06 cm) plant height was recorded from M3 and the shortest (21.69 cm) was found from control. The maximum (28.29) number of leaves per plant was recorded from M3, while the minimum (21.15) was found from control. The maximum (487.48 g) leaf yield per plant was recorded from M3, while the minimum (326.59 g) was found from control. The maximum (14.40%) dry matter content in plant was recorded from M3, while the minimum (12.28%) was found from control. The maximum ( 11.03 kg) yield per plot was recorded from M3, while the minimum (5.27 kg) was found from control. Maximum yield (45.96 t/ha) was recorded from M3, while the minimum (21.97 t/ha) was found from control al 55 DAT. Among different treatment combinations N2M3 (80 kg N/ha +black polythene mulch) was more effective than those of others. The highest (3.64) benefit cost ratio was performed from the treatment combination of N2M3 and the lowest benefit cost ratio (0.81) was obtained from control treatment i.e. N0M0.