Abstract:
An experiment was conducted at the Agronomy Field Laboratory, Bangladesh
Agricultural University, Mymensingh between December 2013 to May 2014. The purpose
of the experiment was to investigate the combined effect of herbicides on the weed
management of rice. The experiment consisted of two varieties, BR 14 (Gazi) and BRRI
dhan 28 along with nine different weed management treatments such as weedy check, the
recommended dose of Manage 10 WP, recommended dose of Polifit 500 EC, 70% of
Manage+20% of Polifit, 20% of Manage+70% of Polifit, 60% of Manage+20% of Polifit, 20%
of Manage+60% of Polifit, 50% of Manage+20% of Polifit and 20% of Manage+50% of
Polifit. Twelve weed species belonging to five families infested the experimental plots. In
the BR14 Variety at 20, 40 and 60 days after transplanting (DAT), lower weed population/
m2 and weed dry weight (g/m2), but higher weed control efficiencies of 65.52, 60.35 and
66.98% were realized, respectively. The recommended dose of Polifit 500 EC treatment
resulted in the lowest weed population and weed dry weight as well as the highest weed
control efficiency of 83.45, 84.93 and 87.07% at 20, 40 and 60 DAT, respectively. Therefore,
to control weeds in an effective manner and in order to get the optimum grain yield in boro
rice, an application of Polifit 500 EC should be applied.
