Abstract:
The experiment was conducted at the Agronomy research field. Sher-e-Bangla
Agricultural University, Dhaka from November. 2009 to May, 2010 to find out
the allelopathic effect of rice straw and water hyacinth biomass on weed
control and yield of boro
rice. The treatments of the experiment consisted of 2
rice varieties
viz. BRRI dhan29 (V1 ) and BRRI hybrid dhan2 (V
2 ); 2
allelopathic materials viz,
rice straw (Mi) and water hyacinth (M
2); and 3 levels
of biomass concentration
viz. 0 kg biomass m 2 (Co
). 0.5 kg biomass m 2 (C1 )
and 1.0 kg biomass m 2 (C2
). The experiment was laid out in a spilt split-plot
design with 3 replications having varieties in the main plots, allelopathic
materials in the sub plots and concentrations in the sub sub-plots. The lowest
weed population (11.33 rn'
2 and 16.00 rn'2 at 30 and 50
DAT respectively) and
minimum dry weight (4.89 g rn'2
) at 30 DAT was found from rice straw
application irrespective of variety. The highest grain yield
(7.50 t ha") was
obtained from BRRI hybrid dhan2 with water hyacinth @ 1.0 kg m
2. The
highest number of effective tillers hilr' (19.67) was observed from BRRI
dhan29 with water hyacinth
@1 1.0 kg m 2
and the lowest number of noneffective
tillers hill (1.67) was recorded from the same variety with rice straw
and
at the same concentration. The highest panicle length (26.65 cm) was
found
in BRRI dhan29 with rice straw @ 1.0 kg biomass m'2.
BRRI hybrid
dhan2,
water hyacinth and 1.0 kg biomass m
2
and their interactions
encouraged growth and dry weight of weeds as well as yield of rice. Rice straw
reduced weed growth whereas water hyacinth enhanced weed growth as well as
grain yield of rice.
Description:
A Thesis
Submitted to the Faculty of Agriculture,
Sher-e-Bangla Agricultural University, Dhaka,
in Partial fulfillment of the requirements for the degree of
MASTER OF SCIENCE (MS)
IN
AGRONOMY
