In a recent interview, Nina Vinot, Director of Business Development at Cybele Agrocare, and Business Development, Bioprox Healthcare, discussed with Muhammad Younis how innovations in microbiome science are transforming agriculture. They explored topics such as integrating plants as holobionts, strategies for enhancing soil health, and the vital role of microbial solutions in promoting sustainability and addressing climate challenges.

#LBS: How can we transform agricultural practices to better integrate the concept of plants as holobionts, nurturing their microbiota, and what key challenges must we overcome to adopt this approach widely?

Nina Vinot: In the context of post-world war 2, fertilizers, made ubiquitous by the recently discovered Haber Bosch process, were the key vector to increase crop productivity and marked the end of traditional farming and the beginning of agriculture modernization. This modernization was also accompanied by excesses with negative consequences such as soil degradation.

Now that the roles of the micro and macrofauna of the soil are better understood – as actors of the maintenance of soil structure and water retention capacity, of the recycling of organic matter, nutrition efficiency, resilience to stress and extension of the root network, agricultural practices are becoming more aware of their biological nature. We are living a second modernization which puts biosolutions at the heart of agricultural resilience and productivity.

Viewing plants as holobionts puts in question some of the most common practices in agriculture. 80% of plants form a symbiosis with mycorrhizae, and tillage breaks fungal hyphae and releases soil organic carbon into the air. Leaving bare soil fails to sustain phytobeneficial microbes which feed on plant exudates, in a win-win partnership. Concentrated chemical fertilizers affect the soil microbiome and reduce the crop’s motivation to recruit its symbionts.

We have to shift perspective and think not just of feeding the plant, but feeding the soil and the plant’s partners who can in turn nourish the crop and sustain it through rough times.

A key challenge is that growers are used to the repeatable effects of chemical solutions independently from the year and pedoclimatic conditions. Microbial inputs bring demonstrated benefits but more variability in their effects. This industry is fine-tuning the recommendations of use to ensure better guarantees and repeatability of the products’ benefits in the field.

Another challenge is that the negative side-effects of some chemical inputs are invisible slowly-growing problems, like the reduction of soil fertility, soil life and organic matter and erosion. Some authors state that a plant will invest in feeding its soil until it reaches a threshold of about 3% of organic matter. Now the average conventional soil has less than 3% of organic matter, thus less resilience, and is hit with increasingly frequent extreme weather events. Like we need the soft power of probiotics and a balanced microbiota to stay healthy but need the acute power of drugs when we are sick, I believe the same approach can apply to agriculture.

#LBS: From your experience with human probiotics, what key insights or strategies do you see as most impactful for enhancing the soil microbiome to improve plant health and yield?

Nina Vinot: The soil microbiome is constituted of a vast array of organisms involved in many metabolic routes, but they need similar things: air, water, nutrients and a comfortable life space. Compacted soils limit the access to these. Tillage is often used as a method to aerate the soil, and while it does in the days after the passage, it destroys fungal hyphae, tears up worms and starves microbes, which all participate in the aeration and building a soil structure made of aggregates, glued together, and galleries which favour gas exchanges and water retention.

Human probiotics are not a magic bullet, if taken together with an unhealthy lifestyle and diet, they are starved of the fiber they need to produce the metabolites that make us healthy. I believe our approach to the soil should be the same: while I strongly believe in the power of microbial biostimulants and biofertilizers to bring back functions and symbiosis with the plants, we should be more attuned to what they need to thrive. Organic matter is a significant part of the answer.

#LBS: What recent developments in microbial biofertilizers and biostimulants stand out as transformative for reducing synthetic fertilizer use and promoting sustainable agriculture? How can we ensure these microbial solutions are accessible and beneficial to farmers on a global scale?

Nina Vinot: Plant symbiosis with legumes has been known for ages and is used in crop rotations as much as the consumer demand permits. But Biological Nitrogen Fixation is not only the scope of legume-associated Rhizobia. There are free diazotrophs whose nitrogenase reductase enzymatic complex can deliver bioavailable nitrogen to many different crops, including field crops like cereals and rapeseed, like those we propose at Cybele Agrocare. These are less well-known, although they can contribute roughly 20% of the nitrogen requirements to the plants. They have the power to reduce drastically the nitrogen fertilizer footprint, the biggest contributor of greenhouse gas emissions in agriculture. The use of these solutions alone could dramatically decarbonate the agriculture footprint and contribute to the European Green Deal’s objectives to reduce by 55% the GHG emissions by 2050 (compared to 1990).

Diazotrophs are not really new, but they are difficult to industrialize, and the low cost of the Haber-Bosh process in an economy of cheap fossil fuels didn’t incentivize their use in the past decades. Even Vaclav Smil seems to ignore their existence, as he stated in How the World Really Works published in 2022 “The best (and long-sought) solution to boost nitrogen supply would be to endow non-leguminous plants with nitrogen-fixing capacities, a promise genetic engineering is yet to deliver on, while a less radical option — inoculating seeds with a nitrogen-fixing bacterium — is a recent innovation whose eventual commercial extent is still unclear.”

To make these solutions broadly accessible to farmers, public policies must promote biosolutions over chemistry, regulations should be better harmonized, technical institutes and distributors sensitized, and their cost of use should be comparable to the traditional fertilizers. Facilitators of this technological uptake include education and continuous training around the mechanisms and interactions at play, and a fair remuneration of the reduction in the exploitations’ carbon footprint.

#LBS: How do you view the role of soil microbes in broader environmental strategies like carbon sequestration and climate change mitigation, and what potential do you see for scaling these solutions?

Nina Vinot: Soil microbes stand at the core of the topics of agriculture decarbonization, carbon sequestration and climate change mitigation. The organic matter present in soils worldwide contains around 1500 billion tonnes of carbon (European Union report on soil and climate) – making soil the largest terrestrial ecosystem for carbon storage. And the first determinant of soil organic carbon formation is microbial carbon use efficiency – an indicator of microbial activity (Tao et al., 2023). Glomales mycorrhizae produce glomalin in abundance, a glycoprotein that stabilizes soil aggregates and represents 27% of the carbon sequestered in the soils (USDA data).

Regarding climate mitigation, the use of diazotrophic biofertilizers as mentioned above is a perfect example of an existing solution to reduce a 100 hectares cereal farm fertilization footprint by about 27 T of CO2eq. With a world surface of 730 million hectares producing cereals (Worldbank.org), that’s a potential reduction of 200 million tonnes of CO2eq emissions. To scale this solution, beyond the levers discussed above (public policies, regulations, education), the carbon credit market should be made more attractive to farmers. Today, it is too complex and expensive for farmers to measure the carbon footprint compared to the economic gains of carbon credits.

#LBS: What is your view about events like the London Biotechnology Show which aims to be a pivotal platform to discuss and display biotech solutions?

Nina Vinot: I have never attended the London Biotechnology Show but an event that connects 3500+ Business Attendees, 110+ Sponsors & Exhibitors, 100+ Speakers and 1800+ Top Biotech Companies is bound to empower biotech solutions uptake and nourish innovation and change. I hope it will avoid the pitfall of techno-solutionarism that fails to encompass the polycrisis complexity and rather aim to foster a better understanding of the interconnectedness of all the food production systems with One Health.