U.
K. Roy, K. S. Islam*, S. N. Islam, M. N. Sarkar, S. Shahanaz, S. Roy
and M. Z. Tareq*
*Corresponding
author, Email: zablulbarj@gmail.com
Abstract
Rice
yellow stem borer (Scirpophaga
incertulas)
is considered as one of the major pest of rice.
An experiment was carried out in the field laboratory, department of
Entomology, Bangladesh Agricultural University to find out the
effectiveness of different insecticides at different time of
application against rice yellow stem borer during the period from
January to June, 2014. The treatments included Impride 17.8 SL
(Imidacloprid),
Mascodan 5 G (Carbofuran),
Aroma 50 SC (Fipronil),
Morter 48 EC (Chlorpyrifos)
at the rates per hectare of 125 ml, 3.24 kg, and 81.78 ml
respectively and also Neem (Azadirachta
indica) Extract at
the rate of 15 ml per liter. The effectiveness were determined by
counting dead heart and white head caused by the attack of rice
yellow stem borer infestation on rice at vegetative, booting and
panicle initiation stages. The reduction of dead heart and white head
varied significantly with time interval due to differential dose of
insecticides. Minimum number of dead heart symptoms were observed in
Mascodan 5 G and minimum with Aroma 50 SC. Percent reduction over
control of dead heart was also high with Mascodan 5 G at both
vegetative and booting stages; and percent reduction over control of
white head was high with Aroma 50 SC in panicle initiation stage.
Again Mascodan 5 G showed highest yield compared to other selective
insecticides. On the other hand, Neem extract was the least effective
one among the applied insecticides showing lower yield although it
was higher than control plot having no insecticides application.
