Standfirst: Tickling plant roots and messing with microbes could be the answer to better crops, finds Sandra Dick.

A healthy portion of spinach and a generous serving of tomato – it could easily be the starting point for a nutritious and healthy salad.

Instead, spinach and tomato are being placed under the microscope as part of a Dundee University study aimed at undoing generations of damage caused to crops by overuse of pesticides and fertilisers.

Researchers hope they can eventually pinpoint the interaction between plants’ roots and microbes in soil to help improve crop production, curb the use of potentially damaging pesticides and fertilisers, and create more nutritious crops.

It could mean that eventually plants can be handed a microbe shot – similar to probiotic ‘healthy bacteria’ drinks which claim to promote gut health for humans – giving them a vital growth boost.

Microbial manipulation is said to have global potential in helping to increase crop yields and making plants more resilient to disease, pests and climate change.

The work is part of a Europe-wide research programme which is looking at developing a range of microbiome-based applications for food production across a range of crops.

Dundee researchers involved in the EU-funded CIRCLES programme are also said to be close to a significant breakthrough in understanding the genetic make-up of the plants they are working.

Unravelling the fine detail of the plants’ genetics and how they shape the microbiome could lead to them being bred to become less dependent on chemicals and more resilient to climate change.

The research is set to be explained in an online talk, Can We Get to the Root of Things?, which is being presented as part of the Royal Society of Edinburgh’s summer Curious programme. The online programme sees researchers and scientists explore a range of topics including space technology, mental health, cancer research, video games, language and artificial intelligence.

Dundee University researcher Dr Senga Robertson-Albertyn’s talk will look at how improving food quality and availability could lie beneath the soil, in plants roots and their unique biome systems.

“Microbes won’t save the world one microbe at a time, this isn’t a magic bullet. But it does have global implications,” said Dr Robertson-Albertyn, who is working on how plant microbiomes in spinach and tomatoes could be tailored to improve quality, productivity, safety and sustainability.

“By tweaking the plant’s microbiome, we could help it be more successful as a crop, or not require as much chemical input.

“It could lead to improved yields using microbes to help plants take up nutrients more effectively, and improve the quality of food.”

Plants have their own microbiome that has evolved over millions of years. However, breeding to create larger yields or boost the size of fruit or grains, along with the use of fertilisers and pesticides have left an impact on how plants recruit important bacteria and affected the balance of microbes in the soil in which they’re grown.

It’s hoped that by unravelling the way plants recruit microbes and introducing ways to encourage a more effective uptake of the ‘healthy’ bacteria, plants can go on to thrive without the need for potentially damaging chemicals.

“We have lost a lot of genetic diversity that impacts on what they recruit bacterially,” added Dr Robertson-Albertyn. “We want to readjust it by adding microbes to plant when put in the ground to help them enrich what they were.”

She added the technology could be particularly useful in areas where farmers do not have access to fertiliser or pesticides which could increase their yield, or where soil conditions are particularly poor or overworked.

“The importance of microbes in plants is becoming more apparent, particularly in light of work on the human gut,” she added. “There are many people now researching plant microbiomes and how we can tweak the microbiome to help the plant be more successful or not require as much chemical input.”

While bacteria inoculant treatments are available which can be added to plants’ soil, often by the time they get to the plants they don’t work because they have to compete with hundreds of thousands of other bacteria present in the soil.

“You can’t just throw bacteria at a plant and expect them to accept it,” she added.

“When you look at adding microbes around the roots of plant, it’s not that you are trying to change or improve the relationship between plants and microbes that has evolved over millions of years,” she added.

“It’s trying to repair some of the changes through breeding and plant management that have altered the way plants are reacting to microbes, and repairing plants to get them back to how they used to be.

“It is a bit like going back to the future.”

Can We Get to the Root of Things? on August 27, is part of the RSE Curious programme.