Effectiveness of commercial formulations of Bacillus thuringiensis var
Kurstaki "Agerin, Dipel 2X and Dipel DF" on total protein and lipid contents were
studied. Activities of detoxification and metabolic enzymes were also measured in
treated and control larvae of cotton leafworm Spodoptera littoralis. Collected samples
from treated larvae at intervals of 48 and 120 hrs post treatment were analyzed to
assess the total protein and lipid contents as well as the enzymes activities. Significant
reductions were observed in total protein content at 120 hrs larvae in all treatments
compared with control. In all larvae treated with Agerin and Dipel DF the lipid
content was significantly elevated after 48 and 120 hrs of treatment while Dipel 2X
showed no significant difference in lipid content. However, fluctuated changes in the
enzymes activity of treated larvae were found. We conclude that there are differences
in biochemical effects between various commercial formulations of Bacillus
thuringiensis kurstaki. In most cases Agerin was found more effective on S. littoralis
than others.
Key words: Bacillus thuringiensis, Spodoptera littoralis, protein, lipid, detoxification enzymes and metabolic enzymes

mona.mansour@fsc.bu.edu.eg