Plants are better than animals at building new genes during periods of evolution, scientists say.
Researchers from the universities of Bristol and Essex came to this conclusion after studying the genomes, an organism’s complete set of DNA, of more than 200 plants.
They traced the origin of land plants to “two explosions of new genes”.
The team says their findings, published in the journal Current Biology, challenges previous understanding that the evolution of plants was a gradual process.
The researchers used sophisticated computer modelling to find out which genes were present in the first land-based plants as they evolved from living in water to setting their roots on land, around 470 million years ago.
They compared the datasets of 208 genomes, covering all major groups of plant species.
Dr Jordi Paps, a lecturer from University of Bristol’s School of Biological Sciences and lead author on the study, said: “After comparing over 200 genomes of the plant kingdom, we discovered that the origin of land plants is associated with two explosions of new genes, an unprecedented level of genomic novelty.
“Our findings challenge previous views of this transition being more gradual at genetic level.”
He said the first of the two explosions predates the origin of land plants, before they left their aquatic environments, while the second coincides with the origin of land plants.
According to Dr Paps, new genes that made plants multi-cellular organisms sometime after the first burst, while genes related to adaptations in terrestrial environments came about following the second explosion.
The team now plans to use the same techniques to identify drought-resistant genes in crops.
Dr Paps added: “We now plan to use the same approach to further explore the genes involved in drought tolerance.
“Most crops are sensitive to drought conditions, using our methods we can find genes involved in drought resistance that we can potentially introduce in dessication-sensitive plants.”