Plants naturally evolve to thrive in their surroundings. But crops have been struggling to keep up with the current pace of climate change. The world is warmer and the global population is increasing, causing farmers around the world to struggle to meet food demand. To support these farmers and improve global food security, the IAEA and FAO, through their Joint FAO/IAEA Centre of Nuclear Techniques in Food and Agriculture, sent seeds into space to explore the effects of cosmic radiation on speeding up natural, genetic adaptation of much needed crops. Their return to Earth, after spending around 5 months at the International Space Station (ISS), paves the way for scientists to start analysing the results.
Arabidopsis and sorghum seeds were chosen because there is already a large bank of scientific data available for comparison. The seeds will now be sent to the laboratories of the Joint FAO/IAEA Centre of Nuclear Techniques in Food and Agriculture in Seibersdorf, Austria, where they will be screened and analysed for desirable traits.
“The cosmic crops project is a very special one,” said IAEA Director General Rafael Mariano Grossi. “This is science that could have a real impact on people’s lives in the not-too-distant future, by helping us grow stronger crops and feed more people.
“IAEA and FAO scientists may have already been mutating seeds for 60 years and creating thousands of stronger crops for the world to use, but this is the first time we have experimented with such an exciting field as astrobiology.”
FAO Director-General QU Dongyu added that “Now that the seeds are back on Earth, we can see the effects of cosmic radiation, microgravity and extreme temperatures and compare them with those induced in our joint laboratories. This ground-breaking experiment can help develop crops that are able to adapt to climate change and boost global food security.”
What happens next?
The Joint FAO/IAEA Centre, based in Vienna, Austria, has been speeding up plant breeding research using radiation to develop new agricultural crop varieties for almost 60 years. In the history of plant agriculture, natural selection or evolution breeding, also called mutation breeding, have been the drivers of crop domestication and plant breeding. They are responsible for the genetic adaptation of plants to their changing environments and lead to the improvement of crops. So far, over 3400 new varieties of more than 210 plant species have been developed using radiation-induced genetic variation and mutation breeding — including numerous food crops, ornamentals and trees used by farmers in 70 countries.
The seeds will now undergo a phytosanitary import process that is a standard requirement for transport of plant material across country borders to minimize the risk of introducing new pests, before final arrival at the laboratories.
Radiation in laboratories typically happens in a machine using gamma rays and X rays, which accelerates the process of spontaneous genetic variation. Scientists work to identify positive traits in irradiated seeds and introduce that trait into future generations. In this way, plants evolve faster with desirable qualities, including resistance to disease and tolerance to drought. The wide range and heavier radiation in space combined with other extremes such as microgravity and temperature could trigger genetic changes not normally encountered with radiation sources on Earth.
“This is the first feasibility study of the FAO and IAEA to determine the effect of cosmic radiation, microgravity and extreme temperatures on plant genome and biology, towards generating sufficient genetic variation for enhanced adaptation to climate change,” explained Shoba Sivasankar, Section Head of Plant Breeding and Genetics at the Joint FAO/IAEA Centre.
Arabidopsis, a type of cress that is easy and inexpensive to grow and produces many seeds, will be tested for tolerance to drought, salt and heat. Sorghum, a nutrient-packed cereal grain that can grow on arid lands and is resilient to changes in climate, will be tested for desirable traits for climate change resilience. Both seeds will be grown to the next generation before trait selection, and with the faster growing Arabidopsis, depending on when they arrive in the laboratories in Seibersdorf, initial results could be available in October 2023.
In both crop species, DNA will be extracted and sequenced, to compare the changes between the seeds that were irradiated in a laboratory, those that were positioned inside the ISS, and those that were positioned outside the ISS and received the full exposure to cosmic radiation, microgravity and extreme temperatures. These comparisons, together with the comparative analysis of plant biology, will help to understand whether harsh space conditions have a uniquely valuable effect for crop improvement and could potentially benefit people on Earth.