Biosafety Testing of Genetically Modified Ryegrass (Lolium perenne) Using a Model for the Optimum Selection of Test Invertebrates

Abstract

Selection of test species for use in biosafety evaluation of genetically modified plants is challenging but important, as regulators in many jurisdictions require tests to determine the potential for adverse environmental impacts before the release of plants into the environment. This contribution provides an example of an evidence-based process whereby species from the receiving environment can be ranked in order of susceptibility to potential impact, and guide test species selection. The case study used for this example was ryegrass, a forage plant, which had been modified to produce elevated levels of the lipid triacylglyceride. The previously described priority ranking of nontarget invertebrates model (PRONTI), designed to rank invertebrates for biosafety testing, has been adapted for use with these plants, which could, potentially, be beneficial to invertebrate populations, and applied to data on 246 known pasture invertebrate species. The output from the model for the top 20 ranked pasture invertebrate species is discussed, the attributes of these are considered along with the level of uncertainty in the information used. Consideration is given to how the model output can be interpreted and used in a biosafety risk assessment. While some subjectivity is involved in establishing the scores, all invertebrate species are subjected to the same analysis, and treated equally. In this way, regulators have a method of a risk assessment that is evidence-based, and transparent in its assumptions thereby avoiding potential for bias.

Responses of 9 lepidopteran species to Bacillus thuringiensis: How useful is phylogenetic relatedness for selecting surrogate species for nontarget arthropod risk assessment?

“…Often it is assumed that nontarget species related to the target species will be more likely to be susceptible to a hazard than unrelated species. Estimates of the value of different organisms, such as their importance for ecosystem functioning, and/or their value to people (e.g., charismatic or rare species) are often also used for further prioritization, as is the availability of established techniques for rearing and testing the organisms in the laboratory (Barratt et al ., ; CERA, ; EFSA, 2010; Li et al ., ; Malone et al ., ; Todd et al ., ; Wang et al ., ).…”