Monitoring insecticide resistance in greenhouse populations of bemisia tabaci (gennadius) (hemiptera: aleyrodidae) and lethal and sub-lethal effects of selected insecticides on its parasitoid eretmocerus mundus mercet (hymenoptera: aphelinidae)

Bemisia tabaci is a notorious pest of many crops of agricultural importance. Chemical control is widely used to supress the pest but its development of resistance to a wide array of chemicals made its management very challenging. Eretmocerus mundus is an effective and promising parasitoid of the whitefly. The aim of the study was to monitor insecticide resistance in greenhouse populations of B. tabaci from Mersin, Turkey and to determine side-effect of insecticides on its parasitoid. All whitefly populations were identified as MEAM-1 species. Resistance ratios were in the range of 3.63–8.79-fold for acetamiprid; 7.29–15.29-fold for imidacloprid, and 9.74–11.79-fold for thiamethoxam after 72hrs of exposure. All populations showed no resistance to spinetoram, spinosad and sulfoxaflor. The endosymbiont bacteria Portiera and Hamiltonella infected all populations at higher level, whereas only two out of five greenhouse-collected whitefly populations were infected with Rickettsia with the highest incidence was detected for the reference population. All the tested insecticides were harmful to both E. mundus pupae and adults, and also negatively affected biological parameters of the parasitoid resulting in disrupted parasitism, longevity, survival, sex ratio and time of juvenile development.