Biodiversity Theme Report

Australia State of the Environment Report 2001 (Theme Report)
Prepared by: Dr Jann Williams, RMIT University, Authors
Published by CSIRO on behalf of the Department of the Environment and Heritage, 2001
ISBN 0 643 06749 3

Biodiversity Issues and Challenges (continued)

Exotic Species and Genetically Modified Organisms (continued)

Genetically modified organisms

  • Distribution and abundance of genetically modified organisms
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    Distribution and abundance of genetically modified organisms [BD Indicator 4.1]

    A GMO is any organism with genetic material that has been altered by genetic engineering. GMO research programs have much in common with traditional plant and animal breeding programs whose intention is to produce individuals with new genetic composition, better adapted to the needs of agriculture, medicine or some other productive use. GMOs are novel because the tools of molecular biology allow genes to be introduced into species that would be difficult or impossible using traditional breeding techniques. There are potential ecological benefits from genetically modified (GM) plants and animals, including the prospect of plant varieties to rehabilitate salt-affected areas or soils contaminated by heavy metals. Some potential benefits are indirect and difficult to predict, such as reductions in the use of pesticides (Barnes 2000).

    Like other introduced organisms, there is also the potential for ecological costs. With the proliferation of GM products and the almost exponential growth of land use for GM crops (AAS 1999), there is growing interest in the estimation of the risks to the environment of exposure to such products. The major potential hazards for biodiversity posed by GM species may be summarised under four headings (Levin 1992):

    1. transgenic leakage into related wild populations may occur by hybridisation, where genes from the GM species move by cross-pollination into wild relatives of the same or different but closely related species
    2. GM populations may become invasive of natural habitats, competing most intensely with wild relatives
    3. GM species may be a direct hazard to non-target species, where the specific properties of GMOs (e.g. insect resistance in crop plants) may make them allergenic or toxic to a range of species that are part of the ecosystem shared by the GM species
    4. GM species may have indirect effects through changes in agricultural practice, including establishment of crops and livestock in areas considered marginal for agriculture, made possible by the novel properties of GMOs.

    The introduction and spread of GMOs in Australia is regulated by the Interim Office of the Gene Technology Regulator and its Genetic Manipulation Advisory Committee (GMAC). Institutional Biosafety Committees (IBCs) operate in institutions where GMO research is undertaken. They oversee the development of new proposals and the conduct of research, acting as a first filter before new ideas are forwarded to GMAC for their consideration. General releases of GMOs are controlled by the Commonwealth Minister for Health and Aged Care under interim arrangements announced by the Commonwealth in August 1999. A national system of statutory regulation will be in place by July 2001.

    Because of the prospect of the spread of genes from GM crops to adjacent non-GM crops, or between related species by hybridisation, buffers between field trials and adjacent wild and non-transgenic crop populations are used. The extent and utility of these buffers has been the focus of some research, with quantification of some aspects of genetic systems, dispersal and gene introgression (di Giovanni & Beckett 1990; Adler et al. 1993; Timmons et al. 1996; Giddings et al. 1997; Hokanson et al. 1997; Moyes & Dale 1999). However, there has been little work on comprehensive, quantitative modelling of ecological risks of GMOs (Timmons et al. 1996; Hails 2000) in Australia or elsewhere.

    Small-scale proposals include laboratory, glasshouse or clinical applications of recombinant DNA under contained conditions. They do not involve the release or cultivation of individuals under field conditions. A total of 4811 small-scale proposals were assessed by GMAC between 1981 and June 1999 (Figure 42). In June 1999, there were 1681 active, small-scale, contained projects.

    Figure 42: Total of small-scale proposals (for laboratory, glasshouse or clinical applications of recombinant DNA under contained conditions) assessed by the Genetic Manipulation Advisory Committee (GMAC) between 1981 and 30 June 1999.

     Total of small-scale proposals (for laboratory, glasshouse or clinical applications of recombinant DNA under contained conditions) assessed by the Genetic Manipulation Advisory Committee (GMAC) between 1981 and 30 June 1999.

    Source: GMAC Annual Report 1997-98 (GMAC 1997) and 1998-99 (GMAC 1999)

    Deliberate releases of GMOs involve trials under field conditions and range from areas smaller than 1 ha up to many thousands of hectares, and numbers of individuals ranging from fewer than 50 to many millions. In June 1999, there were 13 large-scale projects and 109 deliberate releases underway, the latter an increase from June 1998 of 69 projects (Table 41). Most deliberate releases are for commercial crops. Cotton (Gossypium spp.) and Canola (Brassica spp.) have been the subjects of most attention and make up the bulk of field trials, although more than 30 different kinds of GM species had been trialed up to June 1999 (Table 42). GMOs have been trialed in all Australian states (Table 43). A general release implies that the product is commercially available. There were two general releases in Australia before March 2001, for cotton and carnations.

    Table 41: The number of projects on GMOs current in June 1998 and June 1999 and the number of
    Institutional Biosafety Committees (IBCs) responsible for them
    Year Small-scale contained work Large-scale contained work Deliberate
    releases
    Projects with the potential for unintended release IBCs
    1997-98 1 818 18 40 0 85
    1998-99 1 681 13 109 2 89

    Source: GMAC Annual Report (1997-98) and 1998-99 (see http://www.health.gov.au/ogtr/index.htm).

    Table 42: Proposals for deliberate release of GMOs considered by the Genetic Manipulation Advisory Committee (GMAC) between 1981 and March 2000
    Target species Number of projects Objective of project
    Agrobacterium radiobacter 1 Control of crown gall disease
    Apples 2 Kanamycin resistance
    Baker's Yeast 1 Commercial evaluation of melibiose
    Barley 4 Barley yellow dwarf virus resistance; expression of marker genes
    Canola 32 Protoplast fusion breeding lines; new hybridisation systems; seed increase; glufosinate ammonium tolerance; glyphosate herbicide tolerance; fungal disease resistance; photoperiod insensitivity; reduced glucosinolate content; dwarfed cultivars; reduced pod-shatter
    Carnation 8 Modified colour, enhanced vase life; fungal resistance
    Cattle 5 Bovine rhinotracheitis vaccine; salmonella vaccine in lactating dairy cows; release of bovine herpes virus for vaccination
    Chrysanthemum 1 Glasshouse trial of transgenics
    Cotton 90 Insect resistance (Bt); seed increase; glycophosate tolerance; 2,4-D resistance; bromoxynil resistance; yield and fibre tests; climate response assessment; integrated pest management & ecological assessment; progeny selection; Verticillium wilt tolerance; waterlogging tolerance
    Field Pea 11 Enhanced grain sulfur levels; pea weevil (Bruchus pisorum) resistance; resistance to Ascochyta blight; resistance to Liberty
    Grapevine 1 Evaluation of transgenes
    Helicoverpa armigera 4 Transgenics for monitoring frequency of Bt resistance in field; dispersal, stability and transmission of a genetically marked Helicoverpa armigera singly-enveloped nucleopolyhedrovirus in cotton
    Lentils 1 Resistance to Basta
    Lettuce 1 Virus resistance
    Lupins 10 Herbicide resistance (Lupinus angustifolius); virus resistance; sunflower seed albumin
    Oilseed Poppy 3 Field trial and release
    Papaya 2 Virus resistance; superior post-harvest fruit quality
    Pigs 1 No details
    Pineapple 1 Control of flowering and ripening
    Potatoes 9 Resistance to potato leafroll virus and potato virus Y; seed tuber production; viral resistance; low browning properties
    Poultry 2 Salmonella vaccine; evaluation of fowlpox virus vaccine
    Pseudomonas spp. 4 Test of microbial tracking system; non-chemical control of bacterial wilt (Pseudomonas solanacearum); colonisation ability of modified Pseudomonas biological control bacteria on wheat roots in soil
    Rhizobium spp. 2 Field release of strain containing a plasmid marked with a transposon
    Rose 3 Colour modification; kanamycin or chlorsulfuron resistance
    Rumen bacteria 2 Detoxification of fluoroacetate in domestic animals
    Sheep 2 Salmonella vaccine to prevent death during live sheep export
    Subterranean Clover 9 Bromoxynil-tolerance; sunflower seed albumin
    Sugar Cane 5 Resistance to leaf scald disease; resistance to sugarcane mosaic virus; modified sucrose metabolism and juice colour
    Tomato 4 Insect resistance (Bt); seed increase
    Wheat 5 Evaluation of gene flow using a herbicide-resistant marker gene; altered starch composition; modified grain qualities; Basta tolerance; production of a glutenin protein
    White Clover 3 Resistance to alfalfa mosaic virus
    Unknown 1 Fruit ripening and flavour development
    Total 230  

    Source: GMAC Annual Report 1997-98 and 1998-99 (see http://www.health.gov.au/ogtr/publications/index.htm).

    Table 43: The locations by state and territory of deliberate releases of GMOs in Australia to 30 June 1999
    Australia-wide (general release): Agrobacterium, no gall pesticide; carnation, improved vase life and altered flower colour; cotton, insect-resistant (restricted to parts of Qld and NSW).
    ACT New South Wales Queensland Victoria
    Barley Baker's Yeast Apple Canola
    Clover Canola Bovine Herpes Virus 1 Carnation
    Field Pea Clover Canola Clover
    Potato Cotton Cotton Field Pea
    Pseudomonas Field Pea Papaya Grapevine
    Rhizobium Fowlpox Virus Pineapple Indian Mustard
    Wheat Helicoverpa armigera singly-enveloped nucleopolyhedrovirus
    Indian Mustard
    Potato
    Tobacco
    Potato
    Pseudomonas
    Sugar Cane
    Tomato
    Potato
    Rose
    Tomato
    Salmonella
    Northern Territory South Australia Tasmania Western Australia
    Cotton Barley
    Canola
    Field Pea
    Indian Mustard
    Potato
    Pseudomonas
    Wheat
    Canola
    Indian Mustard
    Poppy
    Potato
    Canola
    Clover
    Cotton
    Field Pea
    Lentil
    Lupin
    Salmonella

    Source: GMAC, Canberra.

    GMAC assessed almost all proposals as acceptable, after modification and with different levels of protection being required. Two proposals were rejected, both relating to a project focused on the development of bacteria in the guts of ruminant animals that would allow them to tolerate fluoroacetate poisons that naturally occur in native plant species. One of the concerns was the potential for the bacterium to find its way into the guts of non-target species, perhaps resulting in increased effects on natural vegetation from feral animals. In addition, it is possible that the effect of 1080 bait used in the Western Shield Project in Western Australia (see Managing introduced species) could be reduced if feral animals developed tolerance to these poisons.

    There are several crop genera where Australian native species are found in the same genus (Table 44). Of the species listed, GM varieties of potatoes, tomatoes and cotton have been trialed in the field. Many other crop species have the potential to hybridise with native species outside their genus. For example, there are many Australian species in the family Brassicaceae that could hybridise with crops of Canola and Indian Mustard (genus Brassica). The native species are important in their own right, and represent important reservoirs for genetic resources for crop improvement. These species may be at risk from unwanted hybridisation, both from genetically modified variants and from stock developed by more traditional means. The risk of hybridisation depends on many factors including pollen size and mode of dispersal, seed dispersal mechanisms, timing of flowering, wind direction, water flows, outcrossing rates and the spatial proximity of populations.

    Table 44: Genetically modified crop genera with related Australian native plant species
    Field crops Vegetables Oils, fruits, nuts, spices
    Latin name Common name Latin name Common name Latin name Common name
    Amaranthus Pigweed, Chinese Spinach Abelmoschus Okra B rassica  
    Chenopodium Australian Spinach Alocasia Taro Cinnamomum Cinnamon
    Cajanus Dahl Apium Celery Citrus Orange, Lemon
    Corchorus Jute Cucumis Cucumber Eucalyptus  
    Glycine Soybean Dioscorea Yam Ficus Fig
    Gossypium Cotton Ipomoea Sweet Potato Macadamia  
    Linum Flax Solanum Potato, Tomato Melaleuca Tea-tree
    Nicotiana Tobacco     Musa Banana
    Oryza Rice     Myristica Nutmeg
    Sorghum       Olea Olive
    Vigna Cow pea, Black-eyed Pea     Piper Pepper (white, black etc.)
            Prunus Almond, Peach, Cherry
            Rubus Blackberry
            Syzygium Bush Cherry

    Source: after Brown and Brubaker (2000).