The parasitoid Eretmocerus mundus Mercet (Hymenoptera: Aphelinidae) is one of the key natural enemies of Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae). Lethal and sublethal effects of imidacloprid and buprofezin on emergence and key biological and population parameters of E. mundus exposed during different developmental stages were studied. Dose–response bioassays were carried out on adult wasps using a leaf dipping method. The emergence rates of adults were reduced significantly by the field-recommended concentrations of the insecticides. However, the emergence rates were not affected either by the stage of the parasitoid at the time of exposure (larval and pupal stages), and there was no interaction between treatments and time of exposure. No significant mortality of E. mundus adults was observed following buprofezin treatment. The LC50 of imidacloprid on adults was 4.75 ppm. The results showed that the longevity and fecundity of E. mundus adults were reduced significantly by the two insecticides, though the sex ratio of E. mundus offspring was not affected. Population parameters of the parasitoid such as R0, rm and T were also significantly reduced by the insecticides. Our results indicated that, in addition to lethal effects, sublethal effects should also be considered when these insecticides are applied in IPM programs for this pest.
Source:
Fariba Sohrabia, Parviz Shishehbora, Moosa Saberb, Mohammad Said Mosaddegha. Crop Protection Volume 45, March 2013, Pages 98–103
http://dx.doi.org/10.1016/j.cropro.2012.11.024
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The silverleaf whitefly and Eretmocerus mundus
The silverleaf whitefly (Bemisia tabaci, which is informally referred to as Sweetpotato or Silverleaf whitefly strain B) is one of several whiteflies that are currently important agricultural pests. The Silverleaf whitefly was first found in the United States in poinsettia crops Florida during the mid-1980s. It was found to have moved to tomatoes, other fruit and vegetable crops less than a year later. Within five years, the Silverleaf whitefly had caused over $100 million in damage to the Texas and California agriculture industries. Eretmocerus mundus is very specific and well adapted to control the tobacco whitefly (Bemisia tabaci).
Sources:
Wikipedia
http://en.wikipedia.org/wiki/Silverleaf_whitefly
Biobest
http://www.biobest.be/producten/125/3/0/0/