Abstract:
A study was conducted at the
Eco-toxicology laboratory in the
Department of Agricultural Entomology,
University of Agriculture Faisalabad,
against three species Apis florea, A. dorsata
and A. mellifera of honey bees, to check
long-term survival of honeybees when
exposed to different insecticides. In this
study, we used a modeling approach
regarding survival data of caged bees under
chronic exposure to seven insecticides
(Carbosulfan, Chlorpyrifos, Bifenthrin,
Spinosad, Indoxacarb, Emamectin benzoate
and Imidacloprid), having three replicates
and four concentrations (1000, 500, 250,
125 and 0 ppm). We demonstrate the
chronic toxicity induced by these
insecticides. Laboratory bioassay of these
insecticides showed that carbosulfan and
imidacloprid were the most toxic at their
high dose (1000 ppm) with LT50 of 4 hours
in each case for A. mellifera, chlorpyrifos
and imidacloprid were the most toxic at
their high dose (1000 ppm) with LT50 of 5
hours in each case for A. florea whereas
chlorpyrifos was the most toxic at high dose
(1000 ppm) with LT50 of 5 hours for A.
dorsata. However, LT50 of spinosad was
increased up to 18 hrs with decreasing
concentrations at 125 ppm against A.
mellifera, LT50 of spinosad was increased up
to 15 hrs with decreasing concentrations at
125 ppm against A. florea as well as LT50 of
spinosad and Emamectin benzoate was
increased up to 20 hrs with decreasing
concentrations at 125 ppm against A.
dorsata. However, LT50 of all controlled
species was 91-103 hrs.
