Abstract:
An experiment was conducted in the research field of Sher-e-Bangla Agricultural University,
Dhaka, Bangladesh, from March to August 2021 to evaluate the effect of botanicals on sucking
insect pests and their predators in brinjal. The experiment was laid out in Randomized Complete
Block Design and with three replications. Seven treatments viz. spraying of Neem oil @ 3.0 ml/L
of water at 7 days interval, spraying of Tobacco leaf extract @ 10g/L of water at 7 days interval,
spraying of Garlic extract @ 30g/L of water at 7 days interval, spraying of Papaya leaf extract @
30g/L of water at 7 days interval, spraying of Neem leaf extract @ 20g/L of water at 7 days interval,
spraying of mustard seed extract @ 20g/L of water at 7 days interval, and untreated control were
used to find out their effect. In case of leaf hopper highest reduction over control per plant was
found in neem oil treatment (T
1
) which was 57.73% followed by spraying tobacco leaf extract (T
2
)
50.83%. In case of aphid, plant infestation reduction over control was highest in neem oil treatment
(T
1
) which was 73.62% followed by spraying tobacco leaf extract (T
2
) 47.39% and spraying neem
leaf extract (T
5
) 47.39%. In case of whitefly, reduction of plant infestation was statistically similar
in neem oil application (T
1
) and spraying of tobacco leaf extract (T
2
) 69.97%. In case of red spider
mite, highest reduction over control was found in neem oil application (T
1
) which was 76.37%
followed by spraying tobacco leaf extract (T
2
) 67.10%. Application of neem oil (T
1
) also increased
single fruit weight (104.48%). No negative impact of botanicals was found on predator (lady bird
beetle). In the conclusion it can be revealed that application of neem oil (T
1
) helps to control
sucking insect pests of brinjal, increases the weight of single fruit in the experiment.
Description:
A Thesis
Submitted to Department of Entomology,
Faculty of Agriculture.
Sher-e-Bangla Agricultural University,
Dhaka-
In partial fulfillment of the requirements for the degree of
MASTERS OF SCIENCE (MS)
IN
ENTOMOLOGY
