Researchers at the University of Southampton have suggested that some wild plant species have certain characteristics that make them more suitable for human cultivation than others.
The researchers, who are investigating the origins of domesticated plants, say understanding these key genetic and morphological traits could provide important clues about how to develop future climate-adapted crops.
They suggest that a look at today’s existing unkilled or underutilized plants could help meet future challenges of developing varieties to withstand rising global temperatures and unpredictable weather.
Domesticated plants are those that have been adapted from nature for human use, often over thousands of years. About 12 thousand years ago, hunter-gatherer societies began to cultivate a wide range of species as more reliable sources of food. By repeatedly growing seeds from their best plants each season, humans slowly produced more robust crops with improved yields – but only some of the wild species were domesticated and others were abandoned.
The researchers behind this new study, published in the journal Trends in Ecology and Evolutionsay useful, hidden characteristics of some wild species “primed” them for domestication. Their research reviews a wealth of past literature and evidence to examine why only a minority of these wild plants were domesticated and how modern cultivated varieties differ at the genetic level from their ancestors and today’s wild “cousins”.
Lead author of the study, Professor Mark Chapman of the University of Southampton, explains: “Tens of thousands of plant species are edible, but only a few hundred have been domesticated and just 15 species provide 90 per cent of our calories.
“Hundreds of wild plants were collected during the Neolithic period by humans, but later abandoned as food sources. We have explored what genetic or physical characteristics facilitated or restricted the domestication of wild species.”
The team, which also includes researchers from the Universities of Oxford, Sheffield and the Royal Botanical Gardens at Kew, identified three main influencing factors that make plants suitable for human cultivation:
- Plasticity – how a plant adapts to its environment. Fast and easily adapted plants with traits favored by humans are more likely to have been useful for human cultivation.
- Genetic make-up – the simpler, the better. If a small number of genes influence the traits that humans can benefit from, the development of crop morphology is easier to achieve.
- Mutation rate – the faster, the greater the chance of change. If a plant mutates quickly, the process of trial and error to generate larger seeds or tastier fruits will take less time.
The researchers say that understanding the complex, interrelated factors that lead certain plant species to dominate domesticated crops can help us understand which wild crops can successfully adapt to future conditions caused by climate change.
“When plants were first domesticated thousands of years ago, people only knew the climate and weather conditions they would encounter at the present time,” Professor Chapman explains. “Now, with the help of sophisticated climate modelling, we can predict how our world will warm and how our weather will change in the coming decades. This gives us the opportunity to think about how our crops will need to be resistant in the future. . “
The researchers conclude that today’s wild plants, underutilized crops in local communities, or partially domesticated species may have important, useful traits that can be controlled through selection and precision breeding. They hope their study will help inform future work on adapting species to improve our food security in a rapidly changing world climate.
