Host plant effect on the susceptibility of gypsy moth caterpillars to insecticides

Gypsy moth (Lymantria dispar L) is the most significant pest of broadleaf forests. The dynamics of gypsy moth population depends on several biotic and abiotic factors, but it is also highly dependent on the quality of consumed food. The gypsy moth control increasingly relies on the biological preparations based on Bacillus thuringiensis subspec. kurstaki (Btk) and Lymantria dispar Nuclear Poliedrosis virus (NPV). Chemical preparations are still applied although more rarely, the pyrethroids which include also lambda-cyhalothrin This paper presents the study results of the effect of host plant on gypsy moth caterpillar (Lymantria dispar L) susceptibility to lambda cihalotrine insecticide, by which the study oak leaves were contaminated. The study results show the lowest mortality of the caterpillars fed on contaminated leaves of Turkey oak (17.5%), then pedunculate oak (86.1%), and the highest mortality of caterpillars fed on sessile oak leaves (92%). The rate of the gypsy moth caterpillar development depends on the host plant Susceptibility of the gypsy moth caterpillars to the above preparation depends on the host plant The knowledge of the effect of host plant on insecticide efficiency in gypsy moth suppression would render insecticide utilisation optimal.