Abstract:
An experiment was conducted in the experimental field of Sher-e-Bangla Agricultural
University, Dhaka, Bangladesh during the period from October, 2019 to January,
2020 to evaluate some biopesticides applied against major insect pests of cabbage.
The experiment was laid out in Randomized Complete Block Design (RCBD) with
three replications. Seven treatments, viz. T
(Abamectin 1.2EC @ 1 ml/L of water at 7
days interval); T
2
ii
1
(Azadirachtin 1EC @ 1 ml/L of water at 7 days interval); T
(Potassium salt of fatty acid @ 1 ml/L of water at 7 days interval); T
(Spinosad 45SC
@ 1 ml/L of water at 7 days interval); T
5
4
(Bacillus thuringiensis @ 1 ml/L of water at
7 days interval); T
(Abamectin + Bacillus thuringiensis @ 1 ml/L of water at 7 days
interval) and T
7
6
(untreated control) were used. Among the management practices, the
lowest mean infestation of cabbage leaf by cabbage caterpillar (6.00 leaves/5 plants)
and diamond back moth larvae (4.48 leaves/5 plants) was found in T
treated plot that
reduced the highest leaf infestation over control (62.02% and 49.85 % respectively);
whereas the highest infestation by cabbage caterpillar (15.80 leaves/5 plants) and
diamond back moth larvae (8.93 leaves/5 plants) was found in un treated plot (T
4
).
The lowest mean incidence of cabbage caterpillar (6.82 larvae/5 plants) and
diamondback moth (4.87 larvae/5 plants) was found in T
that reduced highest
incidence over control (50.33% and 51.90% respectively); whereas the highest values
of all these parameters were achieved from untreated control treatment (T
4
).The
lowest cabbage head infestation (21.37%) was recorded in T
, that gave the highest
yield of cabbage (36.40 t/ha) followed by T
1
4
(34.07 t/ha). From the above study it was
found that , the treatment T
comprised of Spinosad 45SC @ 1 ml/L of water at 7
days interval gave the highest performance compared to all other treatments used
under the present study.
Description:
A Thesis
Submitted to the Department of Entomology, Faculty of Agriculture
Sher-e-Bangla Agricultural University, Dhaka
In partial fulfillment of the requirements
for the degree of
MASTER OF SCIENCE (MS)
IN
ENTOMOLOGY
