Table 2 Illustrative classifications for types of properties, stressors, adverse effect scenarios and testable hypotheses
From: Environmental risk assessment of genetically modified plants - concepts and controversies
GM crop | Bt crop | HR crop | Starch-altered crop |
|---|---|---|---|
Property causing adverse effects | Property: insect resistance | Property: herbicide resistance | Property: altered starch composition |
Mechanism: expression of toxin | Mechanism: Expression of altered EPSPS | Mechanism: down- and up-regulation of existing compounds | |
Stressor/mechanism | Primary: Bt-crop and Bt toxin as integral component | Primary: HR-crop and altered EPSPS protein as integral component | Primary: |
High amylopectin content | |||
No amylose content | |||
Secondary: none | Secondary: Herbicide | Secondary: none | |
Adverse effect scenario | Increased mortality of a chrysopid predator feeding on an unaffected plant hopper in Bt maize leads to reduced biocontrol and higher plant hopper infestation | Reduction of the local population of a butterfly species whose larvae feed monophagously on a certain nontarget weed plant occurring mainly in oilseed rape fields. | Increased suitability of amylopectin GM potato for a virus-transmitting aphid. More aphids will now transmit more viruses and create problems for neighbouring crop plants. |
Testable hypotheses | Higher generational mortality among chrysopids raised on Bt maize-fed plant hoppers | Lower densities of caterpillars of the particular butterfly species in fields treated with the corresponding herbicide of the HR oilseed rape than in non-GM oilseed rape fields | Higher reproduction rate and population densities of aphids on amylopectin GM potato than on non-GM isogenic potato |
Higher survival of plant hoppers on Bt maize than on isogenic maize in the presence of a similar number of same-aged chrysopid predators |