You are here

Feeding the planet in the future

Around the world, species of plants can be divided into two groups based on the way they convert carbon dioxide (CO2) from the air into carbohydrate. The majority of plants use what is called a C3 pathway but many species, particularly of tropical origin, use a C4 pathway which is considered a more efficient way of metabolising CO2. C4 plants include many grass species like bamboo and sorghum, as well as our common Kangaroo Grass.

C3 plants are used in many ways all around the world as sources of food. Rice is an example of this, as one of the world’s most critical food crops. Scientists are currently investigating ways to make sure that rice and other valuable crop species are better adapted for the future. One way to adapt such C3 crops for the future would be to transfer the C4 mechanism into them, making them more efficient at metabolising C02. With support from the Grantham Foundation, the Royal Botanic Kew’s Millennium Seed Bank is reaching out around the world to collect plant material with C4 capability. A range of these species is being collected along with related C3 species, making sure to collect a broad genetic diversity from both food and non-food species.

While this is an international project, Australia holds a large number of the required genera and the Australian Seed Bank Partnership is helping to collect plant material for this research. In fact, thirty one of the required genera are now being sought for collection by conservation seed banks across the country. One of these is an interesting and widespread species of grass, Alloteropsis semialata (known as Black Seed grass), which occurs in both C3 and C4 forms and is found around the tropical and subtropical parts of Australia.

        Kangaroo grass (Themeda triandra)
         Photo: Murray Fagg, ANBG