It is widely accepted that natural resources, for example, clean drinking water, are limited and the current ways of using them are not sustainable (for example, see Conservation International, 2008). In addition, with the mounting scientific evidence for climate change (Intergovernmental Panel on Climate Change, 2007), close scrutiny and debate on the ways of using natural resources including plants in more sustainable manners and with minimal or reduced contribution to climate change have already begun.
Human's dependence on crop plants and forestry trees for economic growth and on medicinal or herbal plants for health is undeniably huge. With the dwindling fossil fuels and the associated economic and environmental impacts of using this non-renewable energy resource and stock for chemicals industry, growing plants could take on a new meaning beyond the traditional purpose of feeding, clothing, housing and sourcing medicine for people. Plants (as a biomass resource) could be an alternative renewable energy source and stock for chemicals industry (Martin, 2006). Moreover, growing plants (as a substantial carbon sink), particularly forestry trees, is now considered as at least one of the measures to mitigate the potential effect of climate change (Woodbury et al., 2007; Dore et al., 2008).
Recent advances in plant biology and the development of tools in biotechnology including plant tissue culture and molecular biology hold much promise for quest of sustainable economic growth. However, the potential of these tools of biotechnology has apparently not been explored to any great extent with the indigenous plants in the natural environments of different regions.
Here, global climate change is seen as a new challenge in addition to others that plants have to cope with. The resilience of native plants grown in the natural environments of different countries to any adverse effects of climate change is largely unknown. This should deserve more close scrutiny as it has been projected that even in the case of minimal climate change as many as 20% species including plants could be endangered and "committed" to a path of extinction by 2050 (Thomas et al., 2004). Therefore, this is selected here to aid a discussion of the potential of plant biotechnology applied to safeguard the sustainability of the wild populations of indigenous plants.
Limited natural resources include endangered plants
Plants are generally not considered as limited natural resources. However, plants have enemies such as insect pests and plant disease-causing viruses, bacteria and fungi. Some plants as weeds are more aggressive competitors than others. Disastrous abiotic factors such as prolonged drought, flooding, elevating soil salinity and temperature extremes are not only threats to crop plant production but also to indigenous plants in the natural environments including those that are already endangered. Human activities including farming, mining, industrial and urban living have resulted in heavy metal contamination etc. which could further undermine the sustained survival of wild plant populations. Global climate change is the latest challenge that plants in managed and natural environments alike have to cope with.
In modern agriculture and forestry, plant protection is a significant investment. Agri-chemicals such as pesticides, fungicides and herbicides are important weapons to achieve the level of plant production as we know it (Wilson and Tisdell, 2001). This practice is unsustainable as there are heavy costs to the environment, biodiversity and public health (Wilson and Tisdell, 2001; Huang et al., 2005). Plant biotechnology based on molecular biology-directed gene transfer (genetic engineering) provides some promising alternative solutions to improve defense abilities or abiotic stress tolerance/resilience of crop plants (Gatehouse, 2008). There is still, however, some lingering public concern about the safety and environmental impact of this technology in some countries, for example, in New Zealand. …