Sofia Gomes - Cheating belowground interactions
Hearing the word ‘cheating’, people are most likely to think about human or animal behaviour. But did you know plants can cheat too? Microbiologist Sofia Fernandes Gomes studied plants that deceive the fungi with whom they live together. In the future, these plants may act as indicator species for soil and forest health.
‘For my PhD thesis, I investigated the hidden life of non-green mycoheterotrophic plants’, Gomes tells. ‘These plants deceive the fungi that live at their roots’. These fungi are called mycorrhizal fungi and most plant species on Earth cooperate with them. They help plants to obtain nutrients from the soil in exchange for carbohydrates from the plants. But the plants Gomes studied, do just the opposite: they steal the carbohydrates from their fungi instead of producing them by photosynthesis themselves. Although mycoheterotrophic plants are rare, they can be found all over the globe. Gomes investigated which factors influence the occurrence of these cheater plants.
The plant-mycorrhiza symbiosis is omnipresent, It is very difficult to assess whether two plants are connected by a shared mycorrhizal fungus and to prove that something as a mycorrhizal netwok exists.
Furthermore, it is also extremely hard to replicate their natural structure in the lab. Mycoheterotrophic plants can help elucidate this problem. Because these plants are cheaters, the fungus needs another plants species as partner to get their carbohydrates from. The co-occurrence with this other plant species is a visible proof for the underground mycorrhizal networks. ‘For us, these plants are like a magnifying glass: they offer a unique opportunity to have a glimpse on these intricate networks’, Gomes explains. ‘With my work, we gained more knowledge about their ecology and evolution.’
Although soils are the most biodiverse ecosystems on Earth, soil biodiversity remains a black box for humans. Gomes wants to change this. According to her, mycoheterotrophic plants offer unique systems to understand some of the unknowns of the belowground. ‘I found that these plants are growing on very specific fungi and tend to avoid high fertility soils. Therefore in the future, they may act as indicator species for soil and forest health.’
The work of Gomes highlights the importance of a multidisciplinary approach for a comprehensive understanding of natural systems. She combined techniques and knowledge from the fields of evolutionary biology, ecology and biogeography. In that way she learned more about the biodiversity, ecological preferences and the species distribution of the mycoheterotrophic plants. ‘By focusing on cheater plants, my colleagues and I gained better insights on how green plants work together with the beneficial fungi at their roots, as part of one of the most widespread mutualisms on our planet.