Research Connections and Consulting
Naturalisation potentional and weediness risk assessment for GM Crops
Research Connections and Consulting staff, led by Dr John Rogers, have been responsible for developing new methodologies for naturalisation-potential and weediness-risk assessments for GM crops. Up to now, these assessments have been done as textual analyses using the principles of familiarity and substantial (phenotypic) equivalence. If the transformed plant is deemed to poses no new, or greater, risks than the non-GM plant, then it is considered to pose an acceptable risk.
Over the last year, the Research Connections and Consulting team has made a series of innovations that have dramatically improved the methods for doing naturalisation- potential and weediness-risk assessments for GM crops. Cotton (Gossypium hirsutum) was the first crop to which these improved methods were applied. During the cotton study, the RCAC team made four innovations:
- Firstly, John developed and validated a CLIMEX ® inferential model (http://www.hearne.com.au/products/climex/) for cotton. The model output was then transformed into high resolution maps, showing areas predicted to be suitable for the naturalisation of cotton (Figure 1).
Figure 1: Ecoclimatic Index for cotton in Australia
based on Climex inferential modelling. Most suitable
areas are in red, with decreasingly suitable areas in
yellow and
grey. White areas are either too dry, too
cold, or both.
Figure 2: Suitability index for the naturalisation
of cotton
in Australia combining eco-climatic
and soil limitations. Suitable areas are in red
with decreasingly suitable areas in yellow and
grey. White areas are either too dry, too cold,
or have unsuitable soils, or some combination
of these three.
- The RCAC team then combined these CLIMEX eco-climatic predictions from Figure 1 with soil-suitability data to produce an overall assessment of the likelihood of the crop naturalisation. This final suitability assessment incorporated the effect of temperature, rainfall and soil factors into predictions of where cotton could naturalise in Australia (Figure 2).
-
The third innovation from the RCAC team was to then overlay the predictions from Figure 2 onto very high resolution land-use maps using GIS software, so that realistic assessments could be made of the probability of actual establishment of cotton in potentially suitable areas (Figure 3) . This showed that areas identified as potentially suitable for naturalisation had existing farming systems, principally sugarcane, or established forests.
Figure 3: Overlay of the Suitability Index for cotton
(cross-hatching) and land use data for eastern
Australia from 19.5º S to 29.5º S approximately,
showing that areas of high suitability for naturalisation
of cotton (black cross-hatching) have either existing
farming systems (pink) or forest (dark green).
- Finally, John Rogers applied the Weed Risk Assessment (WRA) Protocol to the assessment of weediness risk of GM cotton, answering the WRA questions specifically for the areas of Australia identified as potentially suitable in Figure 2. Weed Risk Assessment is a validated protocol currently used by Biosecurity Australia (http://www.daff.gov.au) to assess weediness risk for all plant importations into Australia . For the cotton study, the WRA questions were answered separately for non-transgenic, Bollgard II and Roundup Ready Flex cottons, to provide separate weediness risk predictions for each cotton type in the potentially suitable areas identified in Figure 2.
The results of this study were used by the Australian Office of the Gene Technology Regulator as part of assessing Application DIR066/2006 (http://www.ogtr.gov.au/ir/dir066.htm). This research has been accepted for publication in the international journal Agriculture Ecosystems and Environment. A copy of a pre-print of the Agriculture Ecosystems and Environment paper is available at http://www.rcac.net.au/weediness.
The RCAC team can adapt these methods to other GM crops, or to other continents, countries or regions. Contact Research Connections and Consulting for more information about GM-crop naturalisation potential and weediness risk assessments.