Abstract:
The experiment was conducted at Entomology laboratory and Sher-e-Bangla Agricultural
University campus Dhaka during the period from from March, 2011 to May, 2012 to
study host preference and chemical control of mango mealybug. Six chemical
insecticides viz. Lamdacyhalothrin (Fiter 2.5EC), Chlorpyrifos (Dursban 20EC),
Cypermethrin (Ripcord 10EC), Imidacloprid (Bamper 200SL), Dimethoate (Dimetheon
40 EC), Thiamethoxam (Aktara 25WG) were tested field recommended dose on
different stages of mealybug. In field, the experiment was laid out in randomized
complete block design (RCBD) and in laboratory it was set in completely randomized
design (CRD) with three replications. The major hosts of mealybug are mango, jackfruit,
banana, redgram, papaya, cotton, mulberry, guava, tomato, turkey, berry, brinjal, teak,
berry, chilli, marigold etc. Major parts of the plant in where infestation occurs were
inflorescence, succulent leaf, lower surface of leaf mid rib, petiole, leaf bud etc.
Maximum infestation occurs in mango, jackfruit, banana and papaya with 100 percent
infestation rate followed by brinjal, strawberry, chilli and marigold. Immature stages of
the plant are more susceptible. The highest mortality (100%) was found in thiamethoxam
treated insect of 1st instar of mango mealybug in both field and laboratory condition. In
2nd and 3rd instars nymph, chlorpyrifos was most effective. In adult stage, it is more
difficult to control mealy bug by chemical treatment. In field condition 53.33% mortality
was found in chlorpyriphos and 46.67% in lambdacyhalothrin treatment in laboratory
experiment.
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
MASTEROF SCIENCE
IN
ENTOMOLOGY
SEMESTER:JANUARY-JUNE, 2011
