Affiliations: Department of Environmental Biotechnology, Research
Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing
100085, China
Abstract: With the rapid expansion of GEPs (genetically engineered plants),
people are more and more concerned about the ecological risks brought by their
release. Assessing the effect of GEPs on soil microbial ecology is
indispensable to study their ecological risks. In our study, the phospholipids
fatty acid (PLFA) method was used to analyze the microbial community of soil
samples collected from fields with two types of GEPs-Bt transgenic corn and PVY
(potato virus Y) cell protein gene transgenic potato. The principal components
analysis (PCA) showed all controls were on the right of related GEPs samples
along the PC1 (the first principal component) axis, which means a decrease of
fungi in soils with genetically engineered crop since most of PLFAs that are
strongly positively correlated with PC1 represent fungi. For samples collected
from Bt transgenic cornfield, the ratios of gram-positive to gram-negative
bacteria were less than those of controls. For samples of transgenic potato
field, these ratios were lower than those of controls when soils were collected
from deep layer (20–40 cm), but were higher when soils collected from
surface layer (0–20 cm). For soils collected from 0–20 cm, the
ratios of fungi to bacteria for all GEPs samples were at the same level. So
were such rations for all controls. Changes of soil microbial community in two
types of GEPs fields were detected in our study, but the causes and more
information still needs further study.