Microplastics reshape soil microbiomes with implications for plant growth and soil fertility
2026-07-01
A new study reveals that microplastics in soil are far from passive pollutants: depending on polymer type and plant species, they actively reshape the interaction between microbes and plants.
New CRC 1357 Microplastics Publication: Congratulations to Aileen Jung and the research groups led by Tillmann Lüders and Eva Lehndorff (BayCEER), as well as Ryan Bartnick and Daniel Churchill Thomas, on their Editor’s Choice publication:
“Conventional and biodegradable microplastics elicit contrasting taxon-level responses in rhizosphere microbiomes of maize and strawberry” published in FEMS Microbiology Ecology.
Microplastics pose an increasing challenge to agricultural ecosystems, particularly regarding their impact on soil fertility and soil microbial communities. Mulch films, in particular, represent a major source of plastic input into agricultural soils. This study is the first to systematically investigate and compare how conventional (LDPE, PET) and biodegradable (PBAT) microplastics influence both plant growth and rhizosphere microbiomes in maize and strawberry.
The results reveal both plant-specific and polymer-specific effects. Notably, microplastics stimulated the growth of strawberry plants, whereas no such effect was observed for maize. This suggests a short-term improvement in water and nutrient availability in the studied soil. However, the microbial responses differed substantially: biodegradable plastics selectively stimulated specific microbial groups—particularly plastic-degrading bacteria—while conventional plastics caused broad shifts in the rhizosphere microbiome. In particular, the abundance of typical plant growth-promoting microorganisms decreased in the presence of conventional microplastics.
The study highlights the complexity of microplastic effects in agricultural soils. Different types of plastics interact in distinct ways with the composition and functioning of plant-associated soil microbiomes, potentially affecting soil biogeochemistry and crop yields. At the same time, the targeted development of biodegradable polymers offers promising opportunities to mitigate negative impacts or even enhance soil fertility in the long term.
This work provides an important contribution to the ongoing debate on the risks and opportunities associated with different types of plastics in agriculture and supports the transition toward more sustainable materials.