Abstract:
Consequently two experiments was conducted in laboratory of the Department of
Entomology, Sher-e-Bangla Agricultural University, Dhaka-1207 during the period from
July to December, 2017 to damage assessment and study on the biology of sweet potato
weevil Cylas formicarius. Different sweet potato such as BARI sweet potato 2 (kamala
sunduri), BARI sweet potato 4 and local variety of sweet potato were used as
experimental materials. An average incubation period was 4.6±6.188 days under room
conditions on BARI sweet potato 2 in laboratory condition. Total 13.60±1.81 and
6.20±1.095 days were required for larval stage and pupal stage respectively. Adult
longevity of sweet potato weevil, C. formicarius was 81.40±8.11 days. The length of egg
was 0.68 ±0.083 mm and width 0.32±0.083 mm; 1 st , 2 nd and 3 rd instar larval length
were 1.6 ±0.38 mm, 3.76 ±0.36 mm and 5.88 ±0.25 mm respectively and larval width
were 0.28±0.03 mm, 0.52±0.07 mm and 0.81 ±0.04 mm respectively; Pupal length 6.2
±0.36 mm and width 1.0 ±0.13 mm; the length of adult was 6.82 ±0.49 mm and width 1.8
±0.15 mm. At the 1st and 2nd generations on weight basis, % infestation, the highest
infestation was recorded from BARI sweet potato-2 (49.15% and 100.00%, respectively),
which was statistically different from other sweet potatoes and followed by local variety
of sweet potato (41.34 % and 75.05%), whereas, the lowest percent of infestation was
recorded in BARI sweet potato 4 (23.37% and 51.68%, respectively). Present study
showed positive correlation between weight loss and percent of infestation of all varieties
of sweet potato; weight loss increased due to increase of percent of infestation of sweet
potato.
Description:
A Thesis
Submitted to the 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
SEMESTER: JANUARY - JUNE, 2017
