Researchers Investigate Accumulation of Bt Protein in Spider and Prey

Scientists Michael Meissle and Jorg Romeis from Agroscope in Switzerland conducted a study to determine the uptake and fate of Bt protein in Phylloneta impressa, an arthropod predator. Generalist predators like P. impressa could be exposed to Bt protein when they consume preys that fed on Bt crops.

P. impressa were fed with western corn rootworm beetle or lacewig that were reared on Bt maize material. They measured the concentration of Bt protein (Cry3Bb-1) in spiders a day after feeding and recorded that the concentration was 55% in the beetles and 37% in lacewigs. After five days, they found that the Bt protein concentration significantly decreased (90%), indicating rapid excretion, digestion, or both. They also compared the concentrations they obtained after 8 days of feeding and published data on long-term feeding (28-64 days). The long term feeding concentrations were similar or lower than those that went through short-term feeding, implying that Bt protein does not accumulate in the studied arthropods.

Read the research article at http://www.ingentaconnect.com/content/esa/envent/2012/00000041/00000004/art00035.