Sublethal effects of imidacloprid on the predatory seven-spot ladybird beetle Coccinella septempunctata.

The seven-spot ladybird beetle, Coccinella septempunctata, is a major natural enemy of aphids in the field and in greenhouses in China and is part of integrated pest management (IPM). Imidacloprid, a highly efficient insecticide that not only kills aphids at lethal concentrations, but also can cause various sublethal effects in nontarget organisms. To strengthen IPM and its sustainability, it is important assessing possible side effects on natural enemies. When the effects of sublethal concentrations (LC5 and 10%LC5) of imidacloprid on C. septempunctata were evaluated, the adult longevity was shortened by 23.97 and 28.68 %, and the fecundity reduced by 52.81 and 56.09 % compared to control population. In the F1 generation (i.e., the progeny of the exposed individuals), the juvenile development was slower by 1.44 days and 0.66 days, and the oviposition period was shortened by 10 and 13 days, respectively. The fecundity of the F1 generation decreased by 17.88, 44.03 and 51.69 % when exposed to 1%LC5, 10%LC5, and LC5, respectively. The results of demographical growth estimates showed that the intrinsic rate of increase (r m ) and net reproductive rate (R 0 ) were lower in C. septempunctata populations that had been exposed to sublethal concentrations of imidacloprid. The results emphasize the importance of assessing side effects of low imidacloprid concentrations on such predator species, even at the transgenerational level.

[Comparative study of lymphoid follicles in mucosa of pharynx and mucosal associated lymphoid tissues in paranasal sinuses].

OBJECTIVE: To study the relationship between the lymphoid follicles in mucous membrane of pharynx and mucosal associated lymphoid tissues (MALT). METHOD: Ten folliculi obtained from 10 patients of follicular pharyngitis and mucosa taken form 10 patients of paranasal sinusitis were fixed in neutral formalin and embedded in paraffin. Sections were prepared, stained by H. E and by immunohistochemical method staining with S-100,and observe by light microscopy. We observed the morphology of lymphoid follicles in mucous membrane of pharynx with MALT in mucosa of paranasal sinusitis as the contrast. RESULT: Lymphoid follicles in mucosa of pharynx compared with MALT in the mucosa of paranasal sinuses, there was no mantle zone, no typical germinal center and no mucosal epithelium, immunological staining with S-100 was week. CONCLUSION: The lymphoid follicles in mucosa of pharynx does not belong to the MALT.