Imagine if grapevines could remember being stressed and how to respond if it happens again. Early research at the University of Adelaide suggests that this may not be as far-fetched as it seems.
Previous studies have shown it is possible to ‘prime’ individual plants for specific stresses, such as heat, disease or excessive salt, and that this priming is trans-generational; that is, after one sexual generation new plants become more tolerant to the same stress and even to other stresses. This is known as epigenetics.
However, the previous work had only been carried out with plants that propagate via seeds, and not those, like grapevines, that are propagated vegetatively via cuttings.
That’s where Drs Carlos Rodriguez Lopez and Roberta De Bei came in. Funded by Wine Australia, they completed a one-year project to test whether a collection of vines showed the same ability to ‘remember’ after being exposed to drought and excessive heat.
The short answer was that they did, at least for a short time.
‘We found that some markers induced by the stress remained one month after the stress was removed’, Dr Lopez said. ‘Whether the plants were more or less tolerant to heat we don’t know yet because it was a short project. But a memory of the stress was there – and that is significant. We have proof of concept.’
Dr Lopez compares the process to vaccinating people or animals, though there is no vaccine. It is all done through epigenetics, whereby external factors cause specific genes to switch on or off, in response to the stress.
Importantly, no genetic modification is involved. The plants remain exactly as they were originally.
Epigenetics has already been used to create a number of ‘primed’ plants, such as canola that is more efficient at respiration. However, in such cases the memory effect only needs to go through one seed generation.
‘What we want ideally is an epigenetic memory that lasts for the life of the plant, which could be a century in vines’, Dr Lopez said. ‘So it’s not straight forward.’
However, the potential for success with vines is enhanced by the fact that grapevines have a high phenotypic plasticity, which means they are known to adapt well to climate and different growing conditions.
‘Our findings could lead to the production of cuttings that are more tolerant to water and heat stresses, thus reducing costs of irrigation and water applied after planting and plant establishment and so lowering the environmental impact of the Australian wine industry’, the researchers say in their final report to Wine Australia, which can be accessed here.
The proof of concept established through the one-year project will be explored further in a new project, funded through Wine Australia’s recent call for proposals on climate adaptation strategies to manage the impacts of climate change. Click here to read the announcement of our $8.5 million investment over the next 4 years in 12 new research and development (R&D) projects that will help increase demand and the premium paid for Australian wine and increase the grape and wine sector’s competitiveness