The method using which rice can be made to adapt to climate change and some catastrophic events by colonizing its seeds or plants with the spores of tiny naturally occurring fungi has been shown by a US Geological Survey-led research.
USGS researchers and their colleagues colonized two commercial varieties of rice with the spores of fungi that exist naturally within native coastal (salt-tolerant) and geothermal (heat-tolerant) plants.
The experiments were "quite successful", revealed author and Seattle-based USGS researcher Rusty Rodriguez, Ph.D.
The rice plants thrived, achieving notable increased tolerance to cold, salt and drought, even though the rice varieties they tested were not naturally adapted to these stressors.
"This is an exciting breakthrough," Rodriguez said.
"The ability of these fungi to colonize and confer stress tolerance, as well as increased seed yields and root systems in rice - a genetically unrelated plant species from the native plants from which the fungi were isolated-suggests that the fungi may be useful in adapting plants to drought, salt and temperature stressors predicted to worsen in future years due to climate change," Rodriguez explained.
In fact, said Rodriguez, using these tiny fungi - called endophytes - is one of the only real strategies available for mitigating the effects of climate change on plants in natural and agricultural ecosystems.
"We have named this emerging area of research "symbiogenics" for symbiosis-altered gene expression. The DNA of the rice plant itself, however, is not changed," Rodriguez said.
"Instead, we are re-creating what normally happens in nature. And with rice yields projected to decrease by 15 percent in developing countries by 2050, such strategies are needed," Rodriguez explained.
The scientists took fungal endophytes from dunegrass, a species exposed to seawater and therefore salt-tolerant, and colonized the rice plants and seeds with its fungal spores, which germinated and infiltrated the plant's tissue.
The results, said Rodriguez, were dramatic: the endophytes reduced water consumption of the plant by up to one half, and increased its growth, the number of seeds it produced, and how much it weighed by as much as 50 percent.
The research, 'Increased Fitness of Rice Plants to Abiotic Stress via Habitat Adapted Symbiosis: A Strategy for Mitigating Impacts of Climate Change', was published in PLoS One, and is available online.