Australian Development of Heat-Resistant Wheat
In 2013 scientists at NASA discovered a new way of using satellites to measure fluorescence in plants. During photosynthesis, plants emit a form of light invisible to the naked eye but detectable from above. Australian scientists are now using state-of-the-art technology to develop hardier crops at a research farm in Narrabri, in north-west New South Wales.
The researchers use drones and thermal cameras to take images of wheat types and how they react to conditions. Measuring how much light passes through a plant also shows how much heat the crop absorbs, retains and releases. Bradley Evans, an environmental data expert working on the project, said while the goal was to increase productivity, the research could also help farmers use resources better and in a more targeted way, including water, pesticides and fertilisers.
Rebecca Thistlethwaite, the researcher behind the heat-tolerant crop trials in Narrabri, said the experiment needed to go through more testing before farmers could use the data. "To be able to get a genotype from a very basic stage to a farmer's paddock takes between seven and 10 years, but we're well into finding material that's going to be heat tolerant in quite the near future," she said. "We just want to make sure the accuracy is as high as possible because if we don't then we're not going to see the variation that we need to see to be able to select for any a-biotic or biotic stress in the future.
Once a heat-tolerant crop is identified, its genotype is recorded by a team of researchers at the plant breeding institute. "Plant breeding for heat tolerance often takes several years to complete … but we are well into finding heat-tolerant material," Ms Thistlethwaite said.
The material can then be sold to wheat companies for the reproduction of heat-tolerant crops. Ms Thistlethwaite said the research being done with wheat crops could also be applied to other flowering crops similar to wheat such as maize and cotton.
"We really want to give them a heat stress at flowering," she said. "The reproductive stage of a wheat plant is really susceptible to heat stress, so anything above 28 degrees around that time and the yield significantly decreases, so we're looking for the plants that do better at that time," she said.
She said once a superior crop was identified, it was tested for another couple of seasons to make sure it was representative across multiple seasons. "Heat tolerance is a really complex thing to measure and to understand," Ms Thistlethwaite said. "There are lots of variables that can affect the way a plant behaves and we want to make sure we've definitely got the material behaving the way we want it to behave."
Breeding for heat tolerance does take a while, although Ms Thistlethwaite said it was achievable in the not-too-distant future.