Effects of the cultivation of genetically modified Bt crops on nontarget soil organisms - Microbial Ecology in Sustainable Agroecosystems - page 177

Table 8.4 Summary of Effects of Cultivation of Bt Crops or Amendment with Bt Proteins on Soil Fungi (continued)

Bt crop/experimental
variable Organism Methods Study location Protein Effect on fungi Source

Culturable amylolytic,
cellulolytic,
proteolytic,
saprotrophic fungi and
AMF

Selective plating
Grid-line intersect
method

Greenhouse Soybean grown in soil

inoculated with
bacterial strains of Bt
(Cry + ), a Bt Cry -
mutant, purified
insecticidal crystal
protein (ICP), or no
treatment

Cry1Ab No difference in fungal

population size; some
transient differences
in numbers when
compared with
control soil
No effect of ICP on
AMF; Cry + and
Cry - Bt strains
inhibited AMF
compared to control

Ferreira et al.
(2003)

Fungi/eukaryotes PLFA Growth

chamber

Soil cultivated with Bt
or non- Bt maize

Cry1Ab
Cry1F

Expression of Cry
protein reduced the
presence of
eukaryotic PLFA in
bulk soils, although it
was not clear which
groups of eukaryotes
were affected

Blackwood
and Buyer
(2004)

AMF species Glomus
mosseae

Sandwich assay
Trypan blue
staining

Laboratory Effects of root exudates

of Bt maize (Events Bt
11 and 176) on AMF
and fungal
recognition

Cry1Ab Root exudates of Bt 176

reduced presymbiotic
hyphal growth and
reduced development
of appressoria

Turrini et al.
(2004)

Fungi Culturing Laboratory Flooded soils amended

with Bt and non- Bt
rice straw

Cry1Ab No effects on the

numbers of culturable
fungi

Wu et al.
(2004b)

(continued)