Vít Latzel (@LatzelV; @IBOTCZ; @popecolIBOT), Institute of Botany of the Czech Academy of Sciences, discusses his article: Transgenerational effects of mycorrhiza are stronger in sexual than in clonal offspring of Fragaria vesca and are partly adaptive
Clonal and sexual offspring of Fragaria vesca in our study. Photo by Vít Latzel.
BackgroundPlants have a great capacity to adjust their phenotypes to the environment—not just during their own lifetimes, but also across generations. This ability, known as transgenerational effects (TGE), lets parent plants pass down information about their environment to their offspring, almost like a survival cheat code. This “environmental memory” can help future generations know what to expect and how to deal with it.
Most studies on TGE have focused on sexual reproduction, where plants make seeds through the fusion of gametes. But many plants, like strawberries, also reproduce asexually using tubers, runners, or other structures, to produce clones that are genetic copies of the parent. While clonal reproduction in plants is very common in nature, there has not been much research comparing how TGE works in these two types of reproduction.
Another big gap in research is how biotic interaction, in addition to abiotic factors like nutrient and water availability, influence TGE. For example, mycorrhizal fungi form partnerships with plant roots, helping them soak up nutrients, especially when phosphorus is in short supply. These fungi can make plants bigger, tougher, and better at handling stress, so it is possible they could impact how TGE works in both clonal and sexual reproduction—but no one had really looked into this until now.
Our Study
We wanted to dig into how mycorrhizal fungi affect the next clonal and sexual generation of plants of wild strawberry (Fragaria vesca). To do this, we used an inbred line of F. vesca where both the clonal and self-fertilised sexual offspring were genetically identical, making them perfect model for our comparison.
Juvenile clonal (left) and sexual (right) offspring prior to being introduced to their new habitat. Photo by Vít Latzel.
In a greenhouse experiment, we grew parent plants with different combinations of mycorrhizal fungi and phosphorus levels. Then, we grew their clonal and sexual offspring in environments that either matched or were different from what the parents experienced. This setup allowed us to see how these fungi and phosphorus availability affected the next generation.
Example of root colonisation by the arbuscular mycorrhizal fungus Rhizophagus irregularis in our offspring. The fungal structures are stained with trypan blue. Photo by Jiří Machač.
What We Found
Mycorrhizal Benefits Depend on Phosphorus: Mycorrhizal fungi helped the plants grow better when phosphorus was low, but the benefits disappeared when phosphorus was high. We learned that the fungi’s impact really depends on the nutrient’s availability.
Stronger Effects in Sexual Offspring: We found that the TGE of mycorrhiza were generally stronger in sexual offspring than in clonal ones. This suggests that sexual reproduction might be better at capturing the benefits (or avoiding the downsides) of past fungal interactions.
Adaptive TGE in Stressful Conditions: In tough conditions, where mycorrhizal associations were not that helpful (like high phosphorus), sexual offspring were able to decrease their interaction with the fungi if their parents had faced similar issues. This showed that TGE can help plants adapt when a relationship with mycorrhiza is not ideal, especially in sexual offspring.
Why This Matters
Our findings highlight the complexity of plant-mycorrhizal interactions across generations and suggest that these effects are not uniform between different reproductive strategies. The stronger TGE we saw in sexual offspring suggests that these offspring might be better equipped to handle changes in their environments compared to clones. This has big implications for understanding how plants adapt, survive, and evolve—it shows that how a plant is made, whether through seeds or clones, and what its parent plants experienced, can really shape its future!