Interactions between plants and microorganisms – at the crossfield between fundamental science and new solutions in plant production

It is hardly surprising that microorganisms are crucial for plant growth and yields. We all know that unregulated pathogenic microorganisms can have fatal consequences for yields. Conversely, microbial activity in the soil is crucial for plant nutrient uptake. However, microorganisms offer much more: Some microorganisms protect the plant against diseases by regulating pathogens or by activating the plant's own immune defense in due time, others enhance plant resistance against drought or salt stress, while others stimulate general plant growth, to name just a few examples.

However, attempts to utilize beneficial microorganisms in plant production at field scale have had limited success – to some extent because it has not been sufficiently recognized that the beneficial effects of microorganisms are a result of interactions between plants and microorganisms. The success of the interaction depends, among other things, on the plant’s ability to establish an environment that attracts and stimulates beneficial organisms. Further, the plant’s physiological ability to respond appropriately to e.g. microbial signaling or growth-regulating molecules is key to success. A prerequisite for utilizing and optimizing interactions between plants and beneficial microorganisms is that these interactions are integrated into plant breeding.

It is therefore very encouraging to experience that the breeding sector and significant funding bodies are recognizing the potential for breeding for beneficial plant-microbe interactions. This means that we now have the opportunity to bring many years of fundamental research on these interactions into play in the development of crop varieties with enhanced resistance towards biotic and abiotic stress factors. I find collaborations with plant physiologists and breeders incredibly enriching – when people, with mutual respect for each other’s expertise, decide to combine individual competencies, we can really create new insights and tangible results. It is also challenging – we aim to get “something” to work at the interface of each other’s expertise, at the limit of our individual knowledge and skills: I know a lot about microorganisms, but not much about plant genetics – the opposite is true for a breeder. Successful collaboration therefore requires a certain amount of patience, humility and responsiveness to each other, but also the opportunity to become a little wiser and a lot more inspired.