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.