Abstract:
The study was carried out in the experimental farm of Sher-e- Bangla Agricultural
University, Dhaka, Bangladesh during the period from January to September 2008
to determine the efficacy of botanicals and some selected synthetic pesticides on
pest complex of chili (Capsicum frutescens). The experiment comprises of eight
treatments and among them first five (T1, T2, T3, T4 & T5) were the application of
botanicals and two others (T6 & T7) were synthetic pesticides. The treatments
were, T1: Neem leaf extract @ 20g/l at 3 days interval, T2: Neem seed extract @
20g/l at 3 days interval, T3: Neem oil @ 15ml/l at 3 days interval, T4: Biskatali
leaf extract @ 20g/l at 3 days interval, T5: Garlic clove extract @ 15ml/l at 3 days
interval, T6: Arozim @ 3g/l at 7 days interval, T7: Thiolux @ 3g/l at 7 days
interval, T8: Untreated control. In total cropping season, the highest incidence
(percentage) of red mites, aphids and white flies on leaves were 62.33%, 26.09%
and 3.32%, respectively and the highest incidence (percentage) of fruit borer on
fruits was 9.21% with the treatment T8. On the other hand, the lowest incidence
(percentage) of red mites, aphids and white flies on leaves were 24.30%, 4.06%
and 0.46%, respectively and the lowest incidence (percentage) of fruit borer on
fruits was 3.88% in T3. In the whole season, the highest infestation (percentage)
on leaves was 3.78% with the treatment T8 and the lowest infestation (percentage)
on leaves was 0.88% with the treatment T3. In case of fruits, the highest
infestation (percentage) was 27.20% with the treatment T8 and the lowest
infestation (percentage) was 7.76% with the treatment T3. Fruit infestation
reduction over control in weight was the highest (59.06%) with treatment T3,
while the lowest (30.59%) reduction was in T1. The highest weight of fruit yield
was 30.22 ton/ha with treatment T3 and the lowest yield was 16.87 ton/ha with
treatment T8. As a whole, among the different treatments botanicals were more
effective than the chemical pesticides.
Description:
A Thesis
Submitted to the Faculty of Agriculture
Sher-e-Bangla Agricultural University, Dhaka,
in partial fulfilment of the requirements
for the degree of
MASTER OF SCIENCE
IN
ENTOMOLOGY
SEMESTER: JULY-DECEMBER, 2008