Abstract:
The experiment was conducted in the experimental field of Sher-e-Bangla Agricultural
University (SAU), Dhaka-1207, Bangladesh, during the period from November 2012 to May
2013 (Boro season) to study the efficacy of some promising chemical insecticides for
controlling rice stem borer, leaf roller and brown plant hopper. The experiment was laid out in a
Randomized Complete Block Design with three replications with six treatments. Treatments
were T1= Untreated control, T2= Virtako 40 WG (Thiamethoxam 20% in combination with
Thiamethoxam Chlorantraniliprole 20%) @ 75 g/ha, T3= Cartap hydrochloride @ 150 g/ha,
T4= Cartap hydrochloride @ 75 g/ha in combination with Thiamethoxam 25% @ 60 g/ha, T5=
Cartap hydrochloride @ 100g/ha in combination with Thiamethoxam 25% @ 60 g /ha, T6=
Cartap hydrochloride @ 150 g /ha in combination with Thiamethoxam 25% @ 60 g /ha.
Among the treatments, T6 comprising Cartap hydrochloride @ 150 g/ha along with
Thiamethoxam @ 60 g/ha was found most effective in reducing the stem borer
infestation than sole Cartap hydrochloride (T3) or any other treatments. On the other
hand, T4 comprising Cartap hydrochloride @ 75 g/ha in combination with
Thiamethoxam @ 60 g/ha was found most effective in reducing the rice leaf roller
infestation and brown plant hopper population in rice field. Though T6 was the most
effective against rice stem borer but its level of reduction was more or less similar to
that of T4 which was comprised of lower dose of Cartap hydrochloride along with
Thiamethoxam and thus T4 was better than T6.
Description:
A Thesis
submitted to
Department of Entomology
Sher-e-Bangla Agricultural University, Dhaka
in partial fulfillment of the requirements
for the degree of
MASTER OF SCIENCE (MS)
IN
ENTOMOLOGY
SEMESTER: JULY-DECEMBER, 2013