| Although herbicide-tolerant crops have become increasingly popular with growers, and the transgenic proteins they express are not known to affect animals or humans, the public is still skeptical about environmental and health risks potentially associated with them. The objective of this study was to quantify potential long-term effects of Roundup Read® (RR) soybean and corn seeds on survival, reproduction, and growth of Folsomia candida (Willem). The experimental approach included daily observation of single individuals of three successive generations, each of which was observed for 152 days (RR soybean) or 100 days (RR corn). Four food treatments were used: Yeast; conventional (non-RR) grains control; 50% RR grain; and 100% RR grain. Neither RR soybean nor RR corn, used as the sole food source, affected the biology of three successive generations of F. candida. Fecundity was highest in yeast-fed animals. Compared to corn, low fecundity and delayed growth of soybean-fed individuals may have been due to secondary metabolites present in soybeans. Differences between generations, particularly in the soybean experiment, did not affect the overall conclusion that neither RR soybeans nor RR corn influenced the biology of F. candida. |
