Effects of the cultivation of genetically modified Bt crops on nontarget soil organisms - Microbial Ecology in Sustainable Agroecosystems - page 170

Table 8.3 Summary of Effects of Cultivation of Bt Crops or Amendment with Bt Proteins on Soil Bacteria (continued)
Organism/activity
tested

Bt crop plant/
experimental variable

Methodology Study location Protein Effect on bacteria Source

Bacterial decomposer
communities

T-RFLP Field: litterbag

studies

Litterbags containing
plant material from Bt
maize (Event
MON863) and non- Bt
maize

Cry3Bb No effect of Bt maize

biomass on bacterial
decomposer communi-
ties; no effect of
Cry3Bb on carbon
residence time or
turnover in soils
amended with Bt
residues

Xue et al.
(2011)

Microbial biomass
carbon
Microbial activities
Soil enzyme activities
(catalase, nitrate
reductase, acid
phosphomonoesterase,
arylsulfatase, and
b-glucosidase)

Fumigation-
extraction
technique
Fluorocine
diacetate
Enzyme assays

Greenhouse One Bt (ZM30) and

two stacked Bt and
cowpea trypsin
inhibitor ( Bt + CpTI)
cottons (ZM41,
sGK321) and their
non- Bt isolines
(ZM16, ZM23,
Shiyuan) cultivated in
greenhouse pots for
4 years

Cry1Ac
CpTI

Negative correlation
between Cry1Ac
content in soil and
most microbial
properties and
enzyme activities;
CryAc and CpTI
proteins persisted in
soil

Chen et al.
(2011)

Source: Adapted and updated with permission from Icoz and Stotzky, 2008b.