Abstract: A laboratory study was made on the effects of transgenic corn expressing cry1Ab toxin from the bacterium Bacillus thuringiensis (Bt) on the life table of an experimental population of corn leaf aphid Rhopalosiphum maidis Fitch. The results showed that no obvious negative effects of two Bt corn hybrids DK647BTY (event MON810) and NX4777 (event Bt11) were observed on the net reproductive rate, average generation time, innate capacity for increase, and finite rate of increase of R. maidis, and there were no significant differences in the rate of alate, mortality of nymph, and longevity and fecundity duration of corn leaf aphid when feeding on Bt and non-Bt corn hybrids, suggesting that Bt corn expressing cry1Ab toxin had no side-effects on the development and reproduction of R. maidis.

Key words: nitrogen deposition, three-dimensional fluorescence spectra, enzyme activity., soil dissolved organic matter (DOM)